ViewVC logotype

Contents of /code/trunk/ChangeLog

Parent Directory Parent Directory | Revision Log Revision Log

Revision 482 - (hide annotations) (download)
Mon Jan 4 15:55:46 2010 UTC (5 years, 3 months ago) by ph10
File size: 179258 byte(s)
Fix partial match bug (code omitted) for \W.

1 nigel 3 ChangeLog for PCRE
2     ------------------
4 ph10 471 Version 8.01 11-Dec-09
5     ----------------------
7     1. If a pattern contained a conditional subpattern with only one branch (in
8 ph10 473 particular, this includes all (DEFINE) patterns), a call to pcre_study()
9     computed the wrong minimum data length (which is of course zero for such
10 ph10 471 subpatterns).
11 ph10 473
12     2. For patterns such as (?i)a(?-i)b|c where an option setting at the start of
13 ph10 472 the pattern is reset in the first branch, pcre_compile() failed with
14     "internal error: code overflow at offset...". This happened only when
15 ph10 473 the reset was to the original external option setting. (An optimization
16     abstracts leading options settings into an external setting, which was the
17 ph10 472 cause of this.)
18 ph10 471
19 ph10 473 3. A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
20     of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
21     assertion pattern did not match (meaning that the assertion was true), it
22     was incorrectly treated as false if the SKIP had been reached during the
23     matching. This also applied to assertions used as conditions.
24 ph10 471
25 ph10 473 4. If an item that is not supported by pcre_dfa_exec() was encountered in an
26     assertion subpattern, including such a pattern used as a condition,
27     unpredictable results occurred, instead of the error return
29 ph10 478
30 ph10 474 5. The C++ GlobalReplace function was not working like Perl for the special
31     situation when an empty string is matched. It now does the fancy magic
32 ph10 478 stuff that is necessary.
34     6. In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
35 ph10 475 removed. (These were left over from very, very early versions of PCRE.)
36 ph10 478
37 ph10 475 7. Some cosmetic changes to the code to make life easier when compiling it
38     as part of something else:
39 ph10 478
40     (a) Change DEBUG to PCRE_DEBUG.
42     (b) In pcre_compile(), rename the member of the "branch_chain" structure
43     called "current" as "current_branch", to prevent a collision with the
44 ph10 475 Linux macro when compiled as a kernel module.
45 ph10 478
46     (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
47     prevent a collision with the Linux macro when compiled as a kernel
48 ph10 475 module.
49 ph10 478
50 ph10 475 8. In pcre_compile() there are some checks for integer overflows that used to
51     cast potentially large values to (double). This has been changed to that
52 ph10 478 when building, a check for int64_t is made, and if it is found, it is used
53     instead, thus avoiding the use of floating point arithmetic. (There is no
54     other use of FP in PCRE.) If int64_t is not found, the fallback is to
55     double.
57     9. Added two casts to avoid signed/unsigned warnings from VS Studio Express
58 ph10 476 2005 (difference between two addresses compared to an unsigned value).
59 ph10 473
60 ph10 478 10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
61     custom one, because of the following reported problem in Windows:
62 ph10 473
63 ph10 478 - libbz2 uses the Pascal calling convention (WINAPI) for the functions
64     under Win32.
65     - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
66     therefore missing the function definition.
67     - The compiler thus generates a "C" signature for the test function.
68     - The linker fails to find the "C" function.
69     - PCRE fails to configure if asked to do so against libbz2.
70 ph10 479
71     11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
72     messages were output:
73 ph10 478
74 ph10 479 Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
75     rerunning libtoolize, to keep the correct libtool macros in-tree.
76     Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
78     I have done both of these things.
79 ph10 480
80     12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
81     most of the time, it *can* run out if it is given a pattern that contains a
82     runaway infinite recursion. I updated the discussion in the pcrestack man
83     page.
84 ph10 481
85     13. Now that we have gone to the x.xx style of version numbers, the minor
86     version may start with zero. Using 08 or 09 is a bad idea because users
87     might check the value of PCRE_MINOR in their code, and 08 or 09 may be
88     interpreted as invalid octal numbers. I've updated the previous comment in
89     configure.ac, and also added a check that gives an error if 08 or 09 are
90     used.
91 ph10 482
92     14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
93     causing partial matching to fail where the end of the subject matched \W.
94 ph10 479
95 ph10 478
96 ph10 479
97 ph10 469 Version 8.00 19-Oct-09
98 ph10 418 ----------------------
100     1. The table for translating pcre_compile() error codes into POSIX error codes
101 ph10 461 was out-of-date, and there was no check on the pcre_compile() error code
102     being within the table. This could lead to an OK return being given in
103 ph10 418 error.
104 ph10 461
105     2. Changed the call to open a subject file in pcregrep from fopen(pathname,
106     "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
107     in a Windows environment.
109 ph10 420 3. The pcregrep --count option prints the count for each file even when it is
110     zero, as does GNU grep. However, pcregrep was also printing all files when
111     --files-with-matches was added. Now, when both options are given, it prints
112     counts only for those files that have at least one match. (GNU grep just
113 ph10 461 prints the file name in this circumstance, but including the count seems
114     more useful - otherwise, why use --count?) Also ensured that the
115 ph10 420 combination -clh just lists non-zero counts, with no names.
116 ph10 461
117     4. The long form of the pcregrep -F option was incorrectly implemented as
118     --fixed_strings instead of --fixed-strings. This is an incompatible change,
119     but it seems right to fix it, and I didn't think it was worth preserving
120     the old behaviour.
122     5. The command line items --regex=pattern and --regexp=pattern were not
123 ph10 422 recognized by pcregrep, which required --regex pattern or --regexp pattern
124 ph10 461 (with a space rather than an '='). The man page documented the '=' forms,
125 ph10 422 which are compatible with GNU grep; these now work.
126 ph10 461
127     6. No libpcreposix.pc file was created for pkg-config; there was just
128 ph10 423 libpcre.pc and libpcrecpp.pc. The omission has been rectified.
129 ph10 461
130 ph10 425 7. Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
131 ph10 461 when UCP support is not needed, by modifying the Python script that
132 ph10 425 generates it from Unicode data files. This should not matter if the module
133     is correctly used as a library, but I received one complaint about 50K of
134     unwanted data. My guess is that the person linked everything into his
135     program rather than using a library. Anyway, it does no harm.
136 ph10 461
137 ph10 426 8. A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
138 ph10 461 was a minimum greater than 1 for a wide character in a possessive
139 ph10 431 repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
140     which had an unlimited repeat of a nested, fixed maximum repeat of a wide
141     character. Chaos in the form of incorrect output or a compiling loop could
142     result.
143 ph10 461
144 ph10 426 9. The restrictions on what a pattern can contain when partial matching is
145 ph10 461 requested for pcre_exec() have been removed. All patterns can now be
146 ph10 426 partially matched by this function. In addition, if there are at least two
147 ph10 435 slots in the offset vector, the offset of the earliest inspected character
148     for the match and the offset of the end of the subject are set in them when
149 ph10 461 PCRE_ERROR_PARTIAL is returned.
151 ph10 428 10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
152     synonymous with PCRE_PARTIAL, for backwards compatibility, and
153     PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
154 ph10 462 and may be more useful for multi-segment matching.
155 ph10 461
156     11. Partial matching with pcre_exec() is now more intuitive. A partial match
157     used to be given if ever the end of the subject was reached; now it is
158     given only if matching could not proceed because another character was
159     needed. This makes a difference in some odd cases such as Z(*FAIL) with the
160     string "Z", which now yields "no match" instead of "partial match". In the
161     case of pcre_dfa_exec(), "no match" is given if every matching path for the
162     final character ended with (*FAIL).
164 ph10 428 12. Restarting a match using pcre_dfa_exec() after a partial match did not work
165 ph10 461 if the pattern had a "must contain" character that was already found in the
166 ph10 428 earlier partial match, unless partial matching was again requested. For
167     example, with the pattern /dog.(body)?/, the "must contain" character is
168     "g". If the first part-match was for the string "dog", restarting with
169 ph10 435 "sbody" failed. This bug has been fixed.
170 ph10 461
171     13. The string returned by pcre_dfa_exec() after a partial match has been
172     changed so that it starts at the first inspected character rather than the
173     first character of the match. This makes a difference only if the pattern
174     starts with a lookbehind assertion or \b or \B (\K is not supported by
175     pcre_dfa_exec()). It's an incompatible change, but it makes the two
176 ph10 435 matching functions compatible, and I think it's the right thing to do.
177 ph10 461
178 ph10 435 14. Added a pcredemo man page, created automatically from the pcredemo.c file,
179 ph10 461 so that the demonstration program is easily available in environments where
180     PCRE has not been installed from source.
182 ph10 435 15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
183 ph10 430 libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
184     library.
185 ph10 461
186 ph10 435 16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
187 ph10 432 It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
188 ph10 461 is not the first non-POSIX option to be added. Clearly some people find
189 ph10 433 these options useful.
190 ph10 461
191     17. If a caller to the POSIX matching function regexec() passes a non-zero
192 ph10 438 value for nmatch with a NULL value for pmatch, the value of
193 ph10 461 nmatch is forced to zero.
195 ph10 437 18. RunGrepTest did not have a test for the availability of the -u option of
196 ph10 461 the diff command, as RunTest does. It now checks in the same way as
197 ph10 437 RunTest, and also checks for the -b option.
198 ph10 461
199 ph10 438 19. If an odd number of negated classes containing just a single character
200     interposed, within parentheses, between a forward reference to a named
201 ph10 461 subpattern and the definition of the subpattern, compilation crashed with
202     an internal error, complaining that it could not find the referenced
203 ph10 438 subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
204 ph10 461 [The bug was that it was starting one character too far in when skipping
205     over the character class, thus treating the ] as data rather than
206     terminating the class. This meant it could skip too much.]
208 ph10 442 20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
209 ph10 461 /g option in pcretest when the pattern contains \K, which makes it possible
210 ph10 442 to have an empty string match not at the start, even when the pattern is
211 ph10 461 anchored. Updated pcretest and pcredemo to use this option.
213 ph10 446 21. If the maximum number of capturing subpatterns in a recursion was greater
214 ph10 461 than the maximum at the outer level, the higher number was returned, but
215     with unset values at the outer level. The correct (outer level) value is
216 ph10 446 now given.
217 ph10 461
218 ph10 447 22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
219     PCRE did not set those parentheses (unlike Perl). I have now found a way to
220     make it do so. The string so far is captured, making this feature
221     compatible with Perl.
222 ph10 461
223     23. The tests have been re-organized, adding tests 11 and 12, to make it
224 ph10 448 possible to check the Perl 5.10 features against Perl 5.10.
225 ph10 461
226 ph10 454 24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
227 ph10 461 pattern matches a fixed length string. PCRE did not allow this; now it
228     does. Neither allows recursion.
230     25. I finally figured out how to implement a request to provide the minimum
231     length of subject string that was needed in order to match a given pattern.
232     (It was back references and recursion that I had previously got hung up
233     on.) This code has now been added to pcre_study(); it finds a lower bound
234 ph10 455 to the length of subject needed. It is not necessarily the greatest lower
235     bound, but using it to avoid searching strings that are too short does give
236     some useful speed-ups. The value is available to calling programs via
237     pcre_fullinfo().
238 ph10 461
239 ph10 455 26. While implementing 25, I discovered to my embarrassment that pcretest had
240     not been passing the result of pcre_study() to pcre_dfa_exec(), so the
241     study optimizations had never been tested with that matching function.
242     Oops. What is worse, even when it was passed study data, there was a bug in
243     pcre_dfa_exec() that meant it never actually used it. Double oops. There
244     were also very few tests of studied patterns with pcre_dfa_exec().
245 ph10 461
246 ph10 457 27. If (?| is used to create subpatterns with duplicate numbers, they are now
247     allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
248     on the other side of the coin, they are no longer allowed to have different
249     names, because these cannot be distinguished in PCRE, and this has caused
250     confusion. (This is a difference from Perl.)
251 ph10 461
252     28. When duplicate subpattern names are present (necessarily with different
253     numbers, as required by 27 above), and a test is made by name in a
254     conditional pattern, either for a subpattern having been matched, or for
255     recursion in such a pattern, all the associated numbered subpatterns are
256 ph10 459 tested, and the overall condition is true if the condition is true for any
257     one of them. This is the way Perl works, and is also more like the way
258     testing by number works.
259 ph10 418
260 ph10 461
261 ph10 412 Version 7.9 11-Apr-09
262 ph10 376 ---------------------
264 ph10 392 1. When building with support for bzlib/zlib (pcregrep) and/or readline
265 ph10 376 (pcretest), all targets were linked against these libraries. This included
266     libpcre, libpcreposix, and libpcrecpp, even though they do not use these
267     libraries. This caused unwanted dependencies to be created. This problem
268 ph10 392 has been fixed, and now only pcregrep is linked with bzlib/zlib and only
269 ph10 376 pcretest is linked with readline.
270 ph10 392
271 ph10 376 2. The "typedef int BOOL" in pcre_internal.h that was included inside the
272     "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
273     moved outside it again, because FALSE and TRUE are already defined in AIX,
274     but BOOL is not.
275 ph10 392
276     3. The pcre_config() function was treating the PCRE_MATCH_LIMIT and
277 ph10 409 PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
278 ph10 392
279 ph10 376 4. The pcregrep documentation said spaces were inserted as well as colons (or
280     hyphens) following file names and line numbers when outputting matching
281 ph10 392 lines. This is not true; no spaces are inserted. I have also clarified the
282 ph10 376 wording for the --colour (or --color) option.
283 ph10 392
284 ph10 378 5. In pcregrep, when --colour was used with -o, the list of matching strings
285     was not coloured; this is different to GNU grep, so I have changed it to be
286     the same.
287 ph10 392
288 ph10 378 6. When --colo(u)r was used in pcregrep, only the first matching substring in
289 ph10 392 each matching line was coloured. Now it goes on to look for further matches
290     of any of the test patterns, which is the same behaviour as GNU grep.
292     7. A pattern that could match an empty string could cause pcregrep to loop; it
293     doesn't make sense to accept an empty string match in pcregrep, so I have
294 ph10 379 locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
295     seems to be how GNU grep behaves.
296 ph10 392
297 ph10 380 8. The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
298 ph10 392 start or after a newline", because the conditional assertion was not being
299     correctly handled. The rule now is that both the assertion and what follows
300     in the first alternative must satisfy the test.
302 ph10 405 9. If auto-callout was enabled in a pattern with a conditional group whose
303 ph10 399 condition was an assertion, PCRE could crash during matching, both with
304     pcre_exec() and pcre_dfa_exec().
305 ph10 392
306     10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
307     used for matching.
309     11. Unicode property support in character classes was not working for
310 ph10 385 characters (bytes) greater than 127 when not in UTF-8 mode.
311 ph10 388
312 ph10 392 12. Added the -M command line option to pcretest.
314 ph10 388 14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
315 ph10 389
316     15. Added the PCRE_NO_START_OPTIMIZE match-time option.
317 ph10 390
318 ph10 392 16. Added comments and documentation about mis-use of no_arg in the C++
319 ph10 390 wrapper.
320 ph10 392
321 ph10 391 17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
322 ph10 392 from Martin Jerabek that uses macro names for all relevant character and
323 ph10 391 string constants.
324 ph10 405
325 ph10 393 18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
326     SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
327 ph10 405 SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
328     these, but not everybody uses configure.
330     19. A conditional group that had only one branch was not being correctly
331     recognized as an item that could match an empty string. This meant that an
332     enclosing group might also not be so recognized, causing infinite looping
333     (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
334     with the subject "ab", where knowledge that the repeated group can match
335 ph10 396 nothing is needed in order to break the loop.
336 ph10 405
337 ph10 397 20. If a pattern that was compiled with callouts was matched using pcre_dfa_
338 ph10 405 exec(), but without supplying a callout function, matching went wrong.
340     21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
341     leak if the size of the offset vector was greater than 30. When the vector
342     is smaller, the saved offsets during recursion go onto a local stack
343     vector, but for larger vectors malloc() is used. It was failing to free
344     when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
345 ph10 400 error, in fact).
346 ph10 405
347 ph10 402 22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
348 ph10 405 heapframe that is used only when UTF-8 support is enabled. This caused no
349     problem, but was untidy.
350 ph10 376
351 ph10 405 23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
352     CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
353     included within another project.
354 ph10 411
355 ph10 407 24. Steven Van Ingelgem's patches to add more options to the CMake support,
356     slightly modified by me:
357 ph10 411
358     (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
359     not building pcregrep.
361 ph10 407 (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
362 ph10 411 if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
364 ph10 408 25. Forward references, both numeric and by name, in patterns that made use of
365     duplicate group numbers, could behave incorrectly or give incorrect errors,
366     because when scanning forward to find the reference group, PCRE was not
367     taking into account the duplicate group numbers. A pattern such as
368     ^X(?3)(a)(?|(b)|(q))(Y) is an example.
369 ph10 411
370     26. Changed a few more instances of "const unsigned char *" to USPTR, making
371     the feature of a custom pointer more persuasive (as requested by a user).
372 ph10 416
373 ph10 411 27. Wrapped the definitions of fileno and isatty for Windows, which appear in
374 ph10 416 pcretest.c, inside #ifndefs, because it seems they are sometimes already
375     pre-defined.
376 ph10 392
377 ph10 416 28. Added support for (*UTF8) at the start of a pattern.
379 ph10 413 29. Arrange for flags added by the "release type" setting in CMake to be shown
380     in the configuration summary.
381 ph10 405
382 ph10 411
383 ph10 374 Version 7.8 05-Sep-08
384 ph10 349 ---------------------
386     1. Replaced UCP searching code with optimized version as implemented for Ad
387     Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
388 ph10 351 stage table and inline lookup instead of a function, giving speed ups of 2
389     to 5 times on some simple patterns that I tested. Permission was given to
390     distribute the MultiStage2.py script that generates the tables (it's not in
391     the tarball, but is in the Subversion repository).
392 ph10 349
393 ph10 351 2. Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
394     scripts.
395 ph10 358
396 ph10 353 3. Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
397     a group with a zero qualifier. The result of the study could be incorrect,
398 ph10 358 or the function might crash, depending on the pattern.
400     4. Caseless matching was not working for non-ASCII characters in back
401 ph10 354 references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
402 ph10 358 It now works when Unicode Property Support is available.
404 ph10 355 5. In pcretest, an escape such as \x{de} in the data was always generating
405     a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
406     non-UTF-8 mode. If the value is greater than 255, it gives a warning about
407 ph10 358 truncation.
408 ph10 349
409 ph10 358 6. Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
411 ph10 357 7. Added two (int) casts to pcregrep when printing the difference of two
412     pointers, in case they are 64-bit values.
413 ph10 371
414     8. Added comments about Mac OS X stack usage to the pcrestack man page and to
415     test 2 if it fails.
417 ph10 359 9. Added PCRE_CALL_CONVENTION just before the names of all exported functions,
418 ph10 371 and a #define of that name to empty if it is not externally set. This is to
419     allow users of MSVC to set it if necessary.
421     10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
422 ph10 359 the convenience functions in the pcre_get.c source file.
423 ph10 371
424 ph10 360 11. An option change at the start of a pattern that had top-level alternatives
425     could cause overwriting and/or a crash. This command provoked a crash in
426 ph10 371 some environments:
428     printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
430 ph10 360 This potential security problem was recorded as CVE-2008-2371.
431 ph10 371
432 ph10 361 12. For a pattern where the match had to start at the beginning or immediately
433     after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
434 ph10 371 pcre_dfa_exec() could read past the end of the passed subject if there was
435 ph10 361 no match. To help with detecting such bugs (e.g. with valgrind), I modified
436     pcretest so that it places the subject at the end of its malloc-ed buffer.
437 ph10 371
438 ph10 364 13. The change to pcretest in 12 above threw up a couple more cases when pcre_
439 ph10 371 exec() might read past the end of the data buffer in UTF-8 mode.
441 ph10 364 14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
442 ph10 371 the data contained the byte 0x85 as part of a UTF-8 character within its
443     first line. This applied both to normal and DFA matching.
445 ph10 366 15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
446 ph10 371 /^[^d]*?$/8 failed to match "abc".
447 ph10 351
448 ph10 371 16. Added a missing copyright notice to pcrecpp_internal.h.
450     17. Make it more clear in the documentation that values returned from
451 ph10 368 pcre_exec() in ovector are byte offsets, not character counts.
452 ph10 357
453 ph10 371 18. Tidied a few places to stop certain compilers from issuing warnings.
454 ph10 368
455 ph10 373 19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
456     supplied by Stefan Weber. I made a further small update for 7.8 because
457 ph10 374 there is a change of source arrangements: the pcre_searchfuncs.c module is
458     replaced by pcre_ucd.c.
459 ph10 371
460 ph10 373
461 ph10 347 Version 7.7 07-May-08
462 ph10 321 ---------------------
464     1. Applied Craig's patch to sort out a long long problem: "If we can't convert
465 ph10 345 a string to a long long, pretend we don't even have a long long." This is
466 ph10 321 done by checking for the strtoq, strtoll, and _strtoi64 functions.
467 ph10 345
468 ph10 322 2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
469     pre-7.6 versions, which defined a global no_arg variable instead of putting
470 ph10 332 it in the RE class. (See also #8 below.)
471 ph10 345
472     3. Remove a line of dead code, identified by coverity and reported by Nuno
473     Lopes.
475 ph10 324 4. Fixed two related pcregrep bugs involving -r with --include or --exclude:
476 ph10 321
477 ph10 324 (1) The include/exclude patterns were being applied to the whole pathnames
478 ph10 345 of files, instead of just to the final components.
480 ph10 324 (2) If there was more than one level of directory, the subdirectories were
481     skipped unless they satisfied the include/exclude conditions. This is
482     inconsistent with GNU grep (and could even be seen as contrary to the
483     pcregrep specification - which I improved to make it absolutely clear).
484     The action now is always to scan all levels of directory, and just
485     apply the include/exclude patterns to regular files.
486 ph10 345
487 ph10 325 5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used
488 ph10 345 --exclude_dir in the tests to avoid scanning .svn directories.
490 ph10 326 6. Applied Craig's patch to the QuoteMeta function so that it escapes the
491 ph10 345 NUL character as backslash + 0 rather than backslash + NUL, because PCRE
492 ph10 326 doesn't support NULs in patterns.
493 ph10 345
494     7. Added some missing "const"s to declarations of static tables in
495     pcre_compile.c and pcre_dfa_exec.c.
497 ph10 328 8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
498 ph10 329 caused by fix #2 above. (Subsequently also a second patch to fix the
499 ph10 345 first patch. And a third patch - this was a messy problem.)
500 ph10 321
501 ph10 345 9. Applied Craig's patch to remove the use of push_back().
503 ph10 332 10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
504     matching function regexec().
505 ph10 345
506     11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
507     which, however, unlike Perl's \g{...}, are subroutine calls, not back
508 ph10 333 references. PCRE supports relative numbers with this syntax (I don't think
509     Oniguruma does).
510 ph10 345
511     12. Previously, a group with a zero repeat such as (...){0} was completely
512 ph10 335 omitted from the compiled regex. However, this means that if the group
513     was called as a subroutine from elsewhere in the pattern, things went wrong
514 ph10 345 (an internal error was given). Such groups are now left in the compiled
515     pattern, with a new opcode that causes them to be skipped at execution
516 ph10 335 time.
517 ph10 345
518 ph10 341 13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
519     to the way PCRE behaves:
520 ph10 345
521 ph10 336 (a) A lone ] character is dis-allowed (Perl treats it as data).
522 ph10 345
523     (b) A back reference to an unmatched subpattern matches an empty string
524 ph10 336 (Perl fails the current match path).
525 ph10 345
526 ph10 341 (c) A data ] in a character class must be notated as \] because if the
527 ph10 345 first data character in a class is ], it defines an empty class. (In
528 ph10 341 Perl it is not possible to have an empty class.) The empty class []
529     never matches; it forces failure and is equivalent to (*FAIL) or (?!).
530     The negative empty class [^] matches any one character, independently
531     of the DOTALL setting.
532 ph10 345
533     14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
534 ph10 340 non-existent subpattern following a character class starting with ']' and
535     containing () gave an internal compiling error instead of "reference to
536     non-existent subpattern". Fortunately, when the pattern did exist, the
537 ph10 345 compiled code was correct. (When scanning forwards to check for the
538 ph10 340 existencd of the subpattern, it was treating the data ']' as terminating
539 ph10 345 the class, so got the count wrong. When actually compiling, the reference
540 ph10 340 was subsequently set up correctly.)
541 ph10 345
542 ph10 341 15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
543 ph10 345 it was being rejected as not supported by pcre_dfa_exec(), even though
544     other assertions are supported. I have made pcre_dfa_exec() support
545     (*FAIL).
547 ph10 342 16. The implementation of 13c above involved the invention of a new opcode,
548 ph10 345 OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
549     cannot be changed at match time, I realized I could make a small
550     improvement to matching performance by compiling OP_ALLANY instead of
551     OP_ANY for "." when DOTALL was set, and then removing the runtime tests
552     on the OP_ANY path.
554     17. Compiling pcretest on Windows with readline support failed without the
555 ph10 343 following two fixes: (1) Make the unistd.h include conditional on
556 ph10 345 HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
558 ph10 344 18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
559 ph10 345 ncurses library to be included for pcretest when ReadLine support is
560     requested, but also to allow for it to be overridden. This patch came from
561     Daniel Bergström.
562 ph10 347
563 ph10 346 19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
564 ph10 347 as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
565     any errors with the current Unicode tables. Thanks to Peter Kankowski for
566     spotting this.
567 ph10 324
568 ph10 332
569 ph10 319 Version 7.6 28-Jan-08
570 ph10 300 ---------------------
572 ph10 302 1. A character class containing a very large number of characters with
573     codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
574     overflow.
575 ph10 309
576     2. Patch to cut out the "long long" test in pcrecpp_unittest when
577     HAVE_LONG_LONG is not defined.
579 ph10 303 3. Applied Christian Ehrlicher's patch to update the CMake build files to
580 ph10 304 bring them up to date and include new features. This patch includes:
581 ph10 309
582 ph10 304 - Fixed PH's badly added libz and libbz2 support.
583     - Fixed a problem with static linking.
584 ph10 312 - Added pcredemo. [But later removed - see 7 below.]
585 ph10 304 - Fixed dftables problem and added an option.
586     - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
588     - Added readline support for pcretest.
589 ph10 309 - Added an listing of the option settings after cmake has run.
591 ph10 314 4. A user submitted a patch to Makefile that makes it easy to create
592     "pcre.dll" under mingw when using Configure/Make. I added stuff to
593     Makefile.am that cause it to include this special target, without
594     affecting anything else. Note that the same mingw target plus all
595     the other distribution libraries and programs are now supported
596     when configuring with CMake (see 6 below) instead of with
597     Configure/Make.
598 ph10 309
599 ph10 308 5. Applied Craig's patch that moves no_arg into the RE class in the C++ code.
600     This is an attempt to solve the reported problem "pcrecpp::no_arg is not
601 ph10 309 exported in the Windows port". It has not yet been confirmed that the patch
602     solves the problem, but it does no harm.
603 ph10 313
604 ph10 311 6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
605 ph10 319 NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
606 ph10 314 with CMake, and also correct the comment about stack recursion.
607 ph10 313
608 ph10 312 7. Remove the automatic building of pcredemo from the ./configure system and
609 ph10 313 from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
610     of a program that users should build themselves after PCRE is installed, so
611     building it automatically is not really right. What is more, it gave
612 ph10 312 trouble in some build environments.
613 ph10 300
614 ph10 319 8. Further tidies to CMakeLists.txt from Sheri and Christian.
615 ph10 308
616 ph10 319
617 ph10 298 Version 7.5 10-Jan-08
618 ph10 263 ---------------------
620     1. Applied a patch from Craig: "This patch makes it possible to 'ignore'
621     values in parens when parsing an RE using the C++ wrapper."
622 ph10 286
623 ph10 264 2. Negative specials like \S did not work in character classes in UTF-8 mode.
624     Characters greater than 255 were excluded from the class instead of being
625     included.
626 ph10 286
627     3. The same bug as (2) above applied to negated POSIX classes such as
628 ph10 265 [:^space:].
629 ph10 286
630 ph10 267 4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
631     defined or documented. It seems to have been a typo for PCRE_STATIC, so
632 ph10 286 I have changed it.
634 ph10 268 5. The construct (?&) was not diagnosed as a syntax error (it referenced the
635 ph10 286 first named subpattern) and a construct such as (?&a) would reference the
636     first named subpattern whose name started with "a" (in other words, the
637 ph10 272 length check was missing). Both these problems are fixed. "Subpattern name
638     expected" is now given for (?&) (a zero-length name), and this patch also
639     makes it give the same error for \k'' (previously it complained that that
640     was a reference to a non-existent subpattern).
641 ph10 286
642 ph10 269 6. The erroneous patterns (?+-a) and (?-+a) give different error messages;
643 ph10 286 this is right because (?- can be followed by option settings as well as by
644 ph10 269 digits. I have, however, made the messages clearer.
645 ph10 286
646 ph10 270 7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
647     than the number used in the conditional) now cause a compile-time error.
648     This is actually not compatible with Perl, which accepts such patterns, but
649     treats the conditional as always being FALSE (as PCRE used to), but it
650     seems to me that giving a diagnostic is better.
651 ph10 286
652 ph10 274 8. Change "alphameric" to the more common word "alphanumeric" in comments
653 ph10 275 and messages.
654 ph10 286
655     9. Fix two occurrences of "backslash" in comments that should have been
656     "backspace".
658     10. Remove two redundant lines of code that can never be obeyed (their function
659     was moved elsewhere).
661     11. The program that makes PCRE's Unicode character property table had a bug
662     which caused it to generate incorrect table entries for sequences of
663 ph10 277 characters that have the same character type, but are in different scripts.
664 ph10 286 It amalgamated them into a single range, with the script of the first of
665 ph10 277 them. In other words, some characters were in the wrong script. There were
666     thirteen such cases, affecting characters in the following ranges:
667 ph10 286
668 ph10 277 U+002b0 - U+002c1
669     U+0060c - U+0060d
670 ph10 286 U+0061e - U+00612
671 ph10 277 U+0064b - U+0065e
672     U+0074d - U+0076d
673     U+01800 - U+01805
674     U+01d00 - U+01d77
675     U+01d9b - U+01dbf
676     U+0200b - U+0200f
677     U+030fc - U+030fe
678     U+03260 - U+0327f
679     U+0fb46 - U+0fbb1
680     U+10450 - U+1049d
681 ph10 286
682 ph10 279 12. The -o option (show only the matching part of a line) for pcregrep was not
683     compatible with GNU grep in that, if there was more than one match in a
684     line, it showed only the first of them. It now behaves in the same way as
685     GNU grep.
686 ph10 286
687     13. If the -o and -v options were combined for pcregrep, it printed a blank
688     line for every non-matching line. GNU grep prints nothing, and pcregrep now
689     does the same. The return code can be used to tell if there were any
690     non-matching lines.
692 ph10 289 14. Added --file-offsets and --line-offsets to pcregrep.
694     15. The pattern (?=something)(?R) was not being diagnosed as a potentially
695 ph10 282 infinitely looping recursion. The bug was that positive lookaheads were not
696 ph10 286 being skipped when checking for a possible empty match (negative lookaheads
697     and both kinds of lookbehind were skipped).
699 ph10 289 16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
700 ph10 284 inclusion of <windows.h> to before rather than after the definition of
701     INVALID_FILE_ATTRIBUTES (patch from David Byron).
702 ph10 263
703 ph10 289 17. Specifying a possessive quantifier with a specific limit for a Unicode
704 ph10 286 character property caused pcre_compile() to compile bad code, which led at
705     runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
706     are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
707     caused the error; without that there was no problem.
708 ph10 263
709 ph10 289 18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
710 ph10 286
711 ph10 289 19. Added --enable-pcretest-libreadline.
712 ph10 286
713 ph10 289 20. In pcrecpp.cc, the variable 'count' was incremented twice in
714 ph10 288 RE::GlobalReplace(). As a result, the number of replacements returned was
715 ph10 298 double what it should be. I removed one of the increments, but Craig sent a
716     later patch that removed the other one (the right fix) and added unit tests
717     that check the return values (which was not done before).
718 ph10 292
719 ph10 291 21. Several CMake things:
720 ph10 287
721 ph10 291 (1) Arranged that, when cmake is used on Unix, the libraries end up with
722 ph10 292 the names libpcre and libpcreposix, not just pcre and pcreposix.
723 ph10 288
724 ph10 292 (2) The above change means that pcretest and pcregrep are now correctly
725     linked with the newly-built libraries, not previously installed ones.
726 ph10 291
728 ph10 298
729     22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
730     crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
731     UTF-8 newline character). The key issue is that the pattern starts .*;
732     this means that the match must be either at the beginning, or after a
733     newline. The bug was in the code for advancing after a failed match and
734     checking that the new position followed a newline. It was not taking
735 ph10 294 account of UTF-8 characters correctly.
736 ph10 298
737     23. PCRE was behaving differently from Perl in the way it recognized POSIX
738     character classes. PCRE was not treating the sequence [:...:] as a
739     character class unless the ... were all letters. Perl, however, seems to
740     allow any characters between [: and :], though of course it rejects as
741     unknown any "names" that contain non-letters, because all the known class
742     names consist only of letters. Thus, Perl gives an error for [[:1234:]],
743     for example, whereas PCRE did not - it did not recognize a POSIX character
744     class. This seemed a bit dangerous, so the code has been changed to be
745     closer to Perl. The behaviour is not identical to Perl, because PCRE will
746     diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
747     treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
748     Perl does, and where it didn't before.
750 ph10 296 24. Rewrite so as to remove the single use of %n from pcregrep because in some
751     Windows environments %n is disabled by default.
752 ph10 292
754 ph10 260 Version 7.4 21-Sep-07
755 ph10 230 ---------------------
757     1. Change 7.3/28 was implemented for classes by looking at the bitmap. This
758 ph10 231 means that a class such as [\s] counted as "explicit reference to CR or
759     LF". That isn't really right - the whole point of the change was to try to
760     help when there was an actual mention of one of the two characters. So now
761     the change happens only if \r or \n (or a literal CR or LF) character is
762 ph10 230 encountered.
763 ph10 231
764     2. The 32-bit options word was also used for 6 internal flags, but the numbers
765     of both had grown to the point where there were only 3 bits left.
766     Fortunately, there was spare space in the data structure, and so I have
767     moved the internal flags into a new 16-bit field to free up more option
768 ph10 230 bits.
769 ph10 231
770     3. The appearance of (?J) at the start of a pattern set the DUPNAMES option,
771     but did not set the internal JCHANGED flag - either of these is enough to
772     control the way the "get" function works - but the PCRE_INFO_JCHANGED
773     facility is supposed to tell if (?J) was ever used, so now (?J) at the
774 ph10 230 start sets both bits.
776 ph10 231 4. Added options (at build time, compile time, exec time) to change \R from
777     matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
778 ph10 230
779 ph10 243 5. doc/pcresyntax.html was missing from the distribution.
781     6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
782 ph10 233 compatibility, even though it is no longer used.
783 ph10 243
784     7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
785 ph10 254 strtoull to pcrecpp.cc to select the available functions in WIN32 when the
786 ph10 259 windows.h file is present (where different names are used). [This was
787 ph10 257 reversed later after testing - see 16 below.]
788 ph10 243
789     8. Changed all #include <config.h> to #include "config.h". There were also
790 ph10 236 some further <pcre.h> cases that I changed to "pcre.h".
791 ph10 243
792 ph10 239 9. When pcregrep was used with the --colour option, it missed the line ending
793 ph10 243 sequence off the lines that it output.
795     10. It was pointed out to me that arrays of string pointers cause lots of
796     relocations when a shared library is dynamically loaded. A technique of
797     using a single long string with a table of offsets can drastically reduce
798     these. I have refactored PCRE in four places to do this. The result is
799 ph10 240 dramatic:
800 ph10 243
801 ph10 240 Originally: 290
802     After changing UCP table: 187
803 ph10 243 After changing error message table: 43
804 ph10 240 After changing table of "verbs" 36
805     After changing table of Posix names 22
806 ph10 243
807 ph10 240 Thanks to the folks working on Gregex for glib for this insight.
808 ph10 247
809 ph10 244 11. --disable-stack-for-recursion caused compiling to fail unless -enable-
810 ph10 247 unicode-properties was also set.
812 ph10 248 12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
813 ph10 231
814 ph10 253 13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
815     checked only for CRLF.
816 ph10 233
817 ph10 259 14. Added casts to pcretest.c to avoid compiler warnings.
819 ph10 256 15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
820 ph10 253
821 ph10 257 16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
822 ph10 259 and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
823     entirely. This removes changes made in 7 above.
824 ph10 256
825 ph10 261 17. The CMake files have been updated, and there is now more information about
826     building with CMake in the NON-UNIX-USE document.
827 ph10 257
828 ph10 261
829 ph10 228 Version 7.3 28-Aug-07
830 ph10 157 ---------------------
832 ph10 189 1. In the rejigging of the build system that eventually resulted in 7.1, the
833     line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
834     brackets there is not right, since it causes compilers to look for an
835     installed pcre.h, not the version that is in the source that is being
836     compiled (which of course may be different). I have changed it back to:
837 ph10 197
838 ph10 189 #include "pcre.h"
839 ph10 197
840     I have a vague recollection that the change was concerned with compiling in
841     different directories, but in the new build system, that is taken care of
842     by the VPATH setting the Makefile.
844 ph10 190 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
845     when the subject happened to end in the byte 0x85 (e.g. if the last
846     character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
847     characters but of course it shouldn't be taken as a newline when it is part
848     of another character. The bug was that, for an unlimited repeat of . in
849     not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
850     characters when looking for a newline.
851 ph10 197
852     3. A small performance improvement in the DOTALL UTF-8 mode .* case.
854     4. Debugging: adjusted the names of opcodes for different kinds of parentheses
855     in debug output.
857 ph10 201 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
858     long printing in the pcrecpp unittest when running under MinGW.
859 ph10 189
860 ph10 197 6. ESC_K was left out of the EBCDIC table.
861 ph10 189
862 ph10 197 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
863     parentheses; I made it 1000, which seemed large enough. Unfortunately, the
864     limit also applies to "virtual nesting" when a pattern is recursive, and in
865     this case 1000 isn't so big. I have been able to remove this limit at the
866     expense of backing off one optimization in certain circumstances. Normally,
867     when pcre_exec() would call its internal match() function recursively and
868     immediately return the result unconditionally, it uses a "tail recursion"
869     feature to save stack. However, when a subpattern that can match an empty
870     string has an unlimited repetition quantifier, it no longer makes this
871     optimization. That gives it a stack frame in which to save the data for
872     checking that an empty string has been matched. Previously this was taken
873     from the 1000-entry workspace that had been reserved. So now there is no
874     explicit limit, but more stack is used.
875 ph10 189
876 ph10 200 8. Applied Daniel's patches to solve problems with the import/export magic
877     syntax that is required for Windows, and which was going wrong for the
878     pcreposix and pcrecpp parts of the library. These were overlooked when this
879     problem was solved for the main library.
880 ph10 197
881 ph10 202 9. There were some crude static tests to avoid integer overflow when computing
882     the size of patterns that contain repeated groups with explicit upper
883     limits. As the maximum quantifier is 65535, the maximum group length was
884     set at 30,000 so that the product of these two numbers did not overflow a
885     32-bit integer. However, it turns out that people want to use groups that
886     are longer than 30,000 bytes (though not repeat them that many times).
887     Change 7.0/17 (the refactoring of the way the pattern size is computed) has
888     made it possible to implement the integer overflow checks in a much more
889     dynamic way, which I have now done. The artificial limitation on group
890     length has been removed - we now have only the limit on the total length of
891     the compiled pattern, which depends on the LINK_SIZE setting.
892 ph10 208
893     10. Fixed a bug in the documentation for get/copy named substring when
894     duplicate names are permitted. If none of the named substrings are set, the
895     functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
896     empty string.
898     11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
899     instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
900     because the ] is interpreted as the first data character and the
901     terminating ] is not found. PCRE has been made compatible with Perl in this
902     regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
903     cause memory overwriting.
905 ph10 206 10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
906     string has been matched (to stop an infinite loop). It was not recognizing
907 ph10 208 a conditional subpattern that could match an empty string if that
908 ph10 206 subpattern was within another subpattern. For example, it looped when
909 ph10 208 trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the
910 ph10 206 condition was not nested. This bug has been fixed.
911 ph10 208
912 ph10 207 12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
913     past the start of the subject in the presence of bytes with the top bit
914     set, for example "\x8aBCD".
915 ph10 211
916 ph10 210 13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
917     (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
918 ph10 200
919 ph10 211 14. Optimized (?!) to (*FAIL).
920 ph10 202
921 ph10 212 15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
922     This restricts code points to be within the range 0 to 0x10FFFF, excluding
923     the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
924     full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
925     does: it's just the validity check that is more restrictive.
926 ph10 220
927     16. Inserted checks for integer overflows during escape sequence (backslash)
928     processing, and also fixed erroneous offset values for syntax errors during
929     backslash processing.
931 ph10 214 17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
932 ph10 220 for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
934 ph10 215 18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
935     caused an overrun.
936 ph10 220
937     19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
938     something other than just ASCII characters) inside a group that had an
939     unlimited repeat caused a loop at compile time (while checking to see
940     whether the group could match an empty string).
942 ph10 217 20. Debugging a pattern containing \p or \P could cause a crash. For example,
943     [\P{Any}] did so. (Error in the code for printing property names.)
944 ph10 210
945 ph10 220 21. An orphan \E inside a character class could cause a crash.
947     22. A repeated capturing bracket such as (A)? could cause a wild memory
948 ph10 218 reference during compilation.
949 ph10 220
950     23. There are several functions in pcre_compile() that scan along a compiled
951     expression for various reasons (e.g. to see if it's fixed length for look
952 ph10 218 behind). There were bugs in these functions when a repeated \p or \P was
953 ph10 220 present in the pattern. These operators have additional parameters compared
954     with \d, etc, and these were not being taken into account when moving along
955 ph10 218 the compiled data. Specifically:
956 ph10 220
957     (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
958     length.
960     (b) An item such as \pL+ within a repeated group could cause crashes or
961 ph10 218 loops.
962 ph10 220
963 ph10 218 (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
964 ph10 220 "reference to non-existent subpattern" error.
966 ph10 221 (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
968 ph10 219 24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
969 ph10 220 characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
970 ph10 211
971 ph10 222 25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
972 ph10 218
973 ph10 227 26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
974 ph10 223 character were causing crashes (broken optimization).
975 ph10 227
976 ph10 224 27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
977 ph10 227 \p or \P) caused a compile-time loop.
979 ph10 226 28. More problems have arisen in unanchored patterns when CRLF is a valid line
980     break. For example, the unstudied pattern [\r\n]A does not match the string
981     "\r\nA" because change 7.0/46 below moves the current point on by two
982     characters after failing to match at the start. However, the pattern \nA
983 ph10 227 *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
984     the same is true. There doesn't seem any very clean way out of this, but
985     what I have chosen to do makes the common cases work: PCRE now takes note
986     of whether there can be an explicit match for \r or \n anywhere in the
987     pattern, and if so, 7.0/46 no longer applies. As part of this change,
988     there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
989     pattern has explicit CR or LF references.
990 ph10 222
991 ph10 227 29. Added (*CR) etc for changing newline setting at start of pattern.
992 ph10 223
993 ph10 227
994 ph10 189 Version 7.2 19-Jun-07
995     ---------------------
997 ph10 157 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
998     which is apparently normally available under Windows.
999 ph10 159
1000     2. Re-jig the pcregrep tests with different newline settings in an attempt
1001     to make them independent of the local environment's newline setting.
1002 ph10 157
1003 ph10 160 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
1004 ph10 165
1005 ph10 161 4. Some of the "internals" tests were previously cut out when the link size
1006     was not 2, because the output contained actual offsets. The recent new
1007 ph10 165 "Z" feature of pcretest means that these can be cut out, making the tests
1008     usable with all link sizes.
1010 ph10 164 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
1011     stack recursion. This gives a massive performance boost under BSD, but just
1012 ph10 165 a small improvement under Linux. However, it saves one field in the frame
1013 ph10 164 in all cases.
1014 ph10 172
1015 ph10 166 6. Added more features from the forthcoming Perl 5.10:
1016 ph10 172
1017 ph10 166 (a) (?-n) (where n is a string of digits) is a relative subroutine or
1018     recursion call. It refers to the nth most recently opened parentheses.
1019 ph10 172
1020 ph10 166 (b) (?+n) is also a relative subroutine call; it refers to the nth next
1021 ph10 172 to be opened parentheses.
1023     (c) Conditions that refer to capturing parentheses can be specified
1024 ph10 167 relatively, for example, (?(-2)... or (?(+3)...
1025 ph10 172
1026 ph10 168 (d) \K resets the start of the current match so that everything before
1027 ph10 172 is not part of it.
1029 ph10 171 (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
1030 ph10 172
1031 ph10 171 (f) \g{name} is another synonym - part of Perl 5.10's unification of
1032 ph10 172 reference syntax.
1033 ph10 182
1034 ph10 175 (g) (?| introduces a group in which the numbering of parentheses in each
1035 ph10 182 alternative starts with the same number.
1036 ph10 172
1037 ph10 182 (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
1039 ph10 172 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
1042     8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not
1043     terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
1044 ph10 170 for detecting groups that can match an empty string.
1045 ph10 159
1046 ph10 172 9. A pattern with a very large number of alternatives (more than several
1047     hundred) was running out of internal workspace during the pre-compile
1048     phase, where pcre_compile() figures out how much memory will be needed. A
1049     bit of new cunning has reduced the workspace needed for groups with
1050     alternatives. The 1000-alternative test pattern now uses 12 bytes of
1051     workspace instead of running out of the 4096 that are available.
1052 ph10 182
1053 ph10 176 10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
1054 ph10 172
1055 ph10 179 11. Applied patch from Google to remove an optimization that didn't quite work.
1056     The report of the bug said:
1057 ph10 182
1058 ph10 179 pcrecpp::RE("a*").FullMatch("aaa") matches, while
1059     pcrecpp::RE("a*?").FullMatch("aaa") does not, and
1060 ph10 182 pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
1061 ph10 185
1062 ph10 184 12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
1063 ph10 185 it matched the wrong number of bytes.
1064 ph10 172
1065 ph10 179
1066 ph10 155 Version 7.1 24-Apr-07
1067 ph10 98 ---------------------
1069 ph10 111 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
1070 ph10 122 that is more "standard", making use of automake and other Autotools. There
1071 ph10 99 is some re-arrangement of the files and adjustment of comments consequent
1072     on this.
1073 ph10 111
1074     2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
1075     for recursive directory scanning broke on some systems because the files
1076     are not scanned in any specific order and on different systems the order
1077     was different. A call to "sort" has been inserted into RunGrepTest for the
1078     approprate test as a short-term fix. In the longer term there may be an
1079 ph10 100 alternative.
1080 ph10 111
1081 ph10 100 3. I had an email from Eric Raymond about problems translating some of PCRE's
1082 ph10 111 man pages to HTML (despite the fact that I distribute HTML pages, some
1083     people do their own conversions for various reasons). The problems
1084     concerned the use of low-level troff macros .br and .in. I have therefore
1085     removed all such uses from the man pages (some were redundant, some could
1086 ph10 113 be replaced by .nf/.fi pairs). The 132html script that I use to generate
1087     HTML has been updated to handle .nf/.fi and to complain if it encounters
1088     .br or .in.
1089 ph10 111
1090 ph10 100 4. Updated comments in configure.ac that get placed in config.h.in and also
1091 ph10 123 arranged for config.h to be included in the distribution, with the name
1092 ph10 111 config.h.generic, for the benefit of those who have to compile without
1093     Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
1095     5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
1096     Weber: (1) pcre_internal.h was missing some function renames; (2) updated
1097 ph10 127 makevp.bat for the current PCRE, using the additional files
1098 ph10 135 makevp_c.txt, makevp_l.txt, and pcregexp.pas.
1099 ph10 111
1100     6. A Windows user reported a minor discrepancy with test 2, which turned out
1101     to be caused by a trailing space on an input line that had got lost in his
1102 ph10 102 copy. The trailing space was an accident, so I've just removed it.
1103 ph10 111
1104 ph10 104 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
1105 ph10 111 that is needed.
1107 ph10 105 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
1108     as "const" (a) because they are and (b) because it helps the PHP
1109     maintainers who have recently made a script to detect big data structures
1110 ph10 111 in the php code that should be moved to the .rodata section. I remembered
1111     to update Builducptable as well, so it won't revert if ucptable.h is ever
1112 ph10 105 re-created.
1113 ph10 111
1114     9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
1115 ph10 107 pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
1116 ph10 111 order to be able to cut out the UTF-8 tables in the latter when UTF-8
1117     support is not required. This saves 1.5-2K of code, which is important in
1118 ph10 107 some applications.
1119 ph10 111
1120 ph10 110 Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
1121 ph10 111 so as not to refer to the tables, even though these functions will never be
1122     called when UTF-8 support is disabled. Otherwise there are problems with a
1123     shared library.
1125 ph10 118 10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
1127     (a) It was defining its arguments as char * instead of void *.
1129 ph10 123 (b) It was assuming that all moves were upwards in memory; this was true
1130     a long time ago when I wrote it, but is no longer the case.
1132 ph10 118 The emulated memove() is provided for those environments that have neither
1133 ph10 123 memmove() nor bcopy(). I didn't think anyone used it these days, but that
1134 ph10 118 is clearly not the case, as these two bugs were recently reported.
1135 ph10 123
1136 ph10 111 11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
1137 ph10 123 and Detrail to create the HTML documentation, the .txt form of the man
1138     pages, and it removes trailing spaces from listed files. It also creates
1139     pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
1140     case, it wraps all the #defines with #ifndefs. This script should be run
1141 ph10 111 before "make dist".
1142 ph10 123
1143 ph10 115 12. Fixed two fairly obscure bugs concerned with quantified caseless matching
1144     with Unicode property support.
1145 ph10 123
1146     (a) For a maximizing quantifier, if the two different cases of the
1147     character were of different lengths in their UTF-8 codings (there are
1148     some cases like this - I found 11), and the matching function had to
1149 ph10 115 back up over a mixture of the two cases, it incorrectly assumed they
1150     were both the same length.
1151 ph10 123
1152     (b) When PCRE was configured to use the heap rather than the stack for
1153     recursion during matching, it was not correctly preserving the data for
1154     the other case of a UTF-8 character when checking ahead for a match
1155     while processing a minimizing repeat. If the check also involved
1156 ph10 115 matching a wide character, but failed, corruption could cause an
1157     erroneous result when trying to check for a repeat of the original
1158     character.
1159 ph10 123
1160 ph10 116 13. Some tidying changes to the testing mechanism:
1161 ph10 98
1162 ph10 116 (a) The RunTest script now detects the internal link size and whether there
1163     is UTF-8 and UCP support by running ./pcretest -C instead of relying on
1164 ph10 123 values substituted by "configure". (The RunGrepTest script already did
1165     this for UTF-8.) The configure.ac script no longer substitutes the
1166     relevant variables.
1168 ph10 116 (b) The debugging options /B and /D in pcretest show the compiled bytecode
1169     with length and offset values. This means that the output is different
1170     for different internal link sizes. Test 2 is skipped for link sizes
1171     other than 2 because of this, bypassing the problem. Unfortunately,
1172     there was also a test in test 3 (the locale tests) that used /B and
1173 ph10 123 failed for link sizes other than 2. Rather than cut the whole test out,
1174     I have added a new /Z option to pcretest that replaces the length and
1175     offset values with spaces. This is now used to make test 3 independent
1176 ph10 122 of link size. (Test 2 will be tidied up later.)
1177 ph10 123
1178     14. If erroroffset was passed as NULL to pcre_compile, it provoked a
1179 ph10 122 segmentation fault instead of returning the appropriate error message.
1180 ph10 134
1181 ph10 131 15. In multiline mode when the newline sequence was set to "any", the pattern
1182 ph10 134 ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
1183     This doesn't seem right; it now treats the CRLF combination as the line
1184     ending, and so does not match in that case. It's only a pattern such as ^$
1185     that would hit this one: something like ^ABC$ would have failed after \r
1186     and then tried again after \r\n.
1188 ph10 131 16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
1189 ph10 134 in an attempt to make files that differ only in their line terminators
1190     compare equal. This works on Linux.
1191 ph10 142
1192 ph10 141 17. Under certain error circumstances pcregrep might try to free random memory
1193     as it exited. This is now fixed, thanks to valgrind.
1194 ph10 142
1195 ph10 141 19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
1196 ph10 142 "abc\r\n\r\n", it found an unwanted second match after the second \r. This
1197     was because its rules for how to advance for /g after matching an empty
1198 ph10 143 string at the end of a line did not allow for this case. They now check for
1199     it specially.
1200 ph10 150
1201     20. pcretest is supposed to handle patterns and data of any length, by
1202     extending its buffers when necessary. It was getting this wrong when the
1203 ph10 147 buffer for a data line had to be extended.
1204 ph10 150
1205 ph10 149 21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
1206 ph10 150 CRLF as a newline sequence.
1207 ph10 152
1208 ph10 151 22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
1209 ph10 152 out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
1210     I have nevertheless tidied it up.
1211 ph10 111
1212 ph10 152 23. Added some casts to kill warnings from HP-UX ia64 compiler.
1213 ph10 123
1214 ph10 153 24. Added a man page for pcre-config.
1215 ph10 152
1216 ph10 153
1217 nigel 93 Version 7.0 19-Dec-06
1218     ---------------------
1220     1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
1221     moving to gcc 4.1.1.
1223     2. The -S option for pcretest uses setrlimit(); I had omitted to #include
1224     sys/time.h, which is documented as needed for this function. It doesn't
1225     seem to matter on Linux, but it showed up on some releases of OS X.
1227     3. It seems that there are systems where bytes whose values are greater than
1228     127 match isprint() in the "C" locale. The "C" locale should be the
1229     default when a C program starts up. In most systems, only ASCII printing
1230     characters match isprint(). This difference caused the output from pcretest
1231     to vary, making some of the tests fail. I have changed pcretest so that:
1233     (a) When it is outputting text in the compiled version of a pattern, bytes
1234     other than 32-126 are always shown as hex escapes.
1236     (b) When it is outputting text that is a matched part of a subject string,
1237     it does the same, unless a different locale has been set for the match
1238     (using the /L modifier). In this case, it uses isprint() to decide.
1240     4. Fixed a major bug that caused incorrect computation of the amount of memory
1241     required for a compiled pattern when options that changed within the
1242     pattern affected the logic of the preliminary scan that determines the
1243     length. The relevant options are -x, and -i in UTF-8 mode. The result was
1244     that the computed length was too small. The symptoms of this bug were
1245     either the PCRE error "internal error: code overflow" from pcre_compile(),
1246     or a glibc crash with a message such as "pcretest: free(): invalid next
1247     size (fast)". Examples of patterns that provoked this bug (shown in
1248     pcretest format) are:
1250     /(?-x: )/x
1251     /(?x)(?-x: \s*#\s*)/
1252     /((?i)[\x{c0}])/8
1253     /(?i:[\x{c0}])/8
1255     HOWEVER: Change 17 below makes this fix obsolete as the memory computation
1256     is now done differently.
1258     5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
1259     wrapper classes; (b) implement a new function in the C++ scanner that is
1260     more efficient than the old way of doing things because it avoids levels of
1261     recursion in the regex matching; (c) add a paragraph to the documentation
1262     for the FullMatch() function.
1264     6. The escape sequence \n was being treated as whatever was defined as
1265     "newline". Not only was this contrary to the documentation, which states
1266     that \n is character 10 (hex 0A), but it also went horribly wrong when
1267     "newline" was defined as CRLF. This has been fixed.
1269     7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
1270     was being set to -1 for the "end of line" case (supposedly a value that no
1271     character can have). Though this value is never used (the check for end of
1272     line is "zero bytes in current character"), it caused compiler complaints.
1273     I've changed it to 0xffffffff.
1275     8. In pcre_version.c, the version string was being built by a sequence of
1276     C macros that, in the event of PCRE_PRERELEASE being defined as an empty
1277     string (as it is for production releases) called a macro with an empty
1278     argument. The C standard says the result of this is undefined. The gcc
1279     compiler treats it as an empty string (which was what was wanted) but it is
1280     reported that Visual C gives an error. The source has been hacked around to
1281     avoid this problem.
1283     9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
1284     builds of pcretest, and changed the call to _setmode() to use _O_BINARY
1285     instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
1286     of them did).
1288     10. Originally, pcretest opened its input and output without "b"; then I was
1289     told that "b" was needed in some environments, so it was added for release
1290     5.0 to both the input and output. (It makes no difference on Unix-like
1291     systems.) Later I was told that it is wrong for the input on Windows. I've
1292     now abstracted the modes into two macros, to make it easier to fiddle with
1293     them, and removed "b" from the input mode under Windows.
1295     11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
1297     12. Added -help and --help to pcretest as an official way of being reminded
1298     of the options.
1300     13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
1301     and pcrecpp.cc because they annoy compilers at high warning levels.
1303     14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
1305     15. Fixed an occurrence of == in configure.ac that should have been = (shell
1306     scripts are not C programs :-) and which was not noticed because it works
1307     on Linux.
1309     16. pcretest is supposed to handle any length of pattern and data line (as one
1310     line or as a continued sequence of lines) by extending its input buffer if
1311     necessary. This feature was broken for very long pattern lines, leading to
1312     a string of junk being passed to pcre_compile() if the pattern was longer
1313     than about 50K.
1315     17. I have done a major re-factoring of the way pcre_compile() computes the
1316     amount of memory needed for a compiled pattern. Previously, there was code
1317     that made a preliminary scan of the pattern in order to do this. That was
1318     OK when PCRE was new, but as the facilities have expanded, it has become
1319     harder and harder to keep it in step with the real compile phase, and there
1320     have been a number of bugs (see for example, 4 above). I have now found a
1321     cunning way of running the real compile function in a "fake" mode that
1322     enables it to compute how much memory it would need, while actually only
1323     ever using a few hundred bytes of working memory and without too many
1324     tests of the mode. This should make future maintenance and development
1325     easier. A side effect of this work is that the limit of 200 on the nesting
1326     depth of parentheses has been removed (though this was never a serious
1327     limitation, I suspect). However, there is a downside: pcre_compile() now
1328     runs more slowly than before (30% or more, depending on the pattern). I
1329     hope this isn't a big issue. There is no effect on runtime performance.
1331     18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
1332     newline (only possible for the last line of a file) and it was a
1333     pattern that set a locale (followed by /Lsomething), pcretest crashed.
1335     19. Added additional timing features to pcretest. (1) The -tm option now times
1336     matching only, not compiling. (2) Both -t and -tm can be followed, as a
1337     separate command line item, by a number that specifies the number of
1338     repeats to use when timing. The default is 50000; this gives better
1339     precision, but takes uncomfortably long for very large patterns.
1341     20. Extended pcre_study() to be more clever in cases where a branch of a
1342     subpattern has no definite first character. For example, (a*|b*)[cd] would
1343     previously give no result from pcre_study(). Now it recognizes that the
1344     first character must be a, b, c, or d.
1346     21. There was an incorrect error "recursive call could loop indefinitely" if
1347     a subpattern (or the entire pattern) that was being tested for matching an
1348     empty string contained only one non-empty item after a nested subpattern.
1349     For example, the pattern (?>\x{100}*)\d(?R) provoked this error
1350     incorrectly, because the \d was being skipped in the check.
1352     22. The pcretest program now has a new pattern option /B and a command line
1353     option -b, which is equivalent to adding /B to every pattern. This causes
1354     it to show the compiled bytecode, without the additional information that
1355     -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
1356     is the same as /B/I).
1358     23. A new optimization is now able automatically to treat some sequences such
1359     as a*b as a*+b. More specifically, if something simple (such as a character
1360     or a simple class like \d) has an unlimited quantifier, and is followed by
1361     something that cannot possibly match the quantified thing, the quantifier
1362     is automatically "possessified".
1364     24. A recursive reference to a subpattern whose number was greater than 39
1365     went wrong under certain circumstances in UTF-8 mode. This bug could also
1366     have affected the operation of pcre_study().
1368     25. Realized that a little bit of performance could be had by replacing
1369     (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
1371     26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
1373     27. Possessive quantifiers such as a++ were previously implemented by turning
1374     them into atomic groups such as ($>a+). Now they have their own opcodes,
1375     which improves performance. This includes the automatically created ones
1376     from 23 above.
1378     28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
1379     lookahead was broken if it was not anchored. PCRE was mistakenly expecting
1380     the first matched character to be a colon. This applied both to named and
1381     numbered groups.
1383     29. The ucpinternal.h header file was missing its idempotency #ifdef.
1385     30. I was sent a "project" file called libpcre.a.dev which I understand makes
1386     building PCRE on Windows easier, so I have included it in the distribution.
1388     31. There is now a check in pcretest against a ridiculously large number being
1389     returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
1390     loop, the loop is abandoned.
1392     32. Forward references to subpatterns in conditions such as (?(2)...) where
1393     subpattern 2 is defined later cause pcre_compile() to search forwards in
1394     the pattern for the relevant set of parentheses. This search went wrong
1395     when there were unescaped parentheses in a character class, parentheses
1396     escaped with \Q...\E, or parentheses in a #-comment in /x mode.
1398     33. "Subroutine" calls and backreferences were previously restricted to
1399     referencing subpatterns earlier in the regex. This restriction has now
1400     been removed.
1402     34. Added a number of extra features that are going to be in Perl 5.10. On the
1403     whole, these are just syntactic alternatives for features that PCRE had
1404     previously implemented using the Python syntax or my own invention. The
1405     other formats are all retained for compatibility.
1407     (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
1408     as (?P<name>...). The new forms, as well as being in Perl 5.10, are
1409     also .NET compatible.
1411     (b) A recursion or subroutine call to a named group can now be defined as
1412     (?&name) as well as (?P>name).
1414     (c) A backreference to a named group can now be defined as \k<name> or
1415     \k'name' as well as (?P=name). The new forms, as well as being in Perl
1416     5.10, are also .NET compatible.
1418     (d) A conditional reference to a named group can now use the syntax
1419     (?(<name>) or (?('name') as well as (?(name).
1421     (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
1422     groups (named and numbered) that are never evaluated inline, but can be
1423     called as "subroutines" from elsewhere. In effect, the DEFINE condition
1424     is always false. There may be only one alternative in such a group.
1426     (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
1427     as the simple (?(R). The condition is true only if the most recent
1428     recursion is that of the given number or name. It does not search out
1429     through the entire recursion stack.
1431     (g) The escape \gN or \g{N} has been added, where N is a positive or
1432     negative number, specifying an absolute or relative reference.
1434     35. Tidied to get rid of some further signed/unsigned compiler warnings and
1435     some "unreachable code" warnings.
1437     36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
1438     things, this adds five new scripts.
1440     37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
1441     There were also incompatibilities regarding the handling of \Q..\E inside
1442     character classes, for example with patterns like [\Qa\E-\Qz\E] where the
1443     hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
1445     38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
1446     matches an empty string, and forcibly breaks the loop. There were bugs in
1447     this code in non-simple cases. For a pattern such as ^(a()*)* matched
1448     against aaaa the result was just "a" rather than "aaaa", for example. Two
1449     separate and independent bugs (that affected different cases) have been
1450     fixed.
1452     39. Refactored the code to abolish the use of different opcodes for small
1453     capturing bracket numbers. This is a tidy that I avoided doing when I
1454     removed the limit on the number of capturing brackets for 3.5 back in 2001.
1455     The new approach is not only tidier, it makes it possible to reduce the
1456     memory needed to fix the previous bug (38).
1458     40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
1459     sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
1460     processing dot, circumflex, or dollar metacharacters, or #-comments in /x
1461     mode.
1463     41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
1464     report.
1466     42. Applied patch, originally from Ari Pollak, modified by Google, to allow
1467     copy construction and assignment in the C++ wrapper.
1469     43. Updated pcregrep to support "--newline=any". In the process, I fixed a
1470     couple of bugs that could have given wrong results in the "--newline=crlf"
1471     case.
1473     44. Added a number of casts and did some reorganization of signed/unsigned int
1474     variables following suggestions from Dair Grant. Also renamed the variable
1475     "this" as "item" because it is a C++ keyword.
1477     45. Arranged for dftables to add
1479     #include "pcre_internal.h"
1481     to pcre_chartables.c because without it, gcc 4.x may remove the array
1482     definition from the final binary if PCRE is built into a static library and
1483     dead code stripping is activated.
1485     46. For an unanchored pattern, if a match attempt fails at the start of a
1486     newline sequence, and the newline setting is CRLF or ANY, and the next two
1487     characters are CRLF, advance by two characters instead of one.
1490 nigel 91 Version 6.7 04-Jul-06
1491     ---------------------
1493     1. In order to handle tests when input lines are enormously long, pcretest has
1494     been re-factored so that it automatically extends its buffers when
1495     necessary. The code is crude, but this _is_ just a test program. The
1496     default size has been increased from 32K to 50K.
1498     2. The code in pcre_study() was using the value of the re argument before
1499     testing it for NULL. (Of course, in any sensible call of the function, it
1500     won't be NULL.)
1502     3. The memmove() emulation function in pcre_internal.h, which is used on
1503     systems that lack both memmove() and bcopy() - that is, hardly ever -
1504     was missing a "static" storage class specifier.
1506     4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
1507     containing an extended class (one that cannot be represented by a bitmap
1508     because it contains high-valued characters or Unicode property items, e.g.
1509     [\pZ]). Almost always one would set UTF-8 mode when processing such a
1510     pattern, but PCRE should not loop if you do not (it no longer does).
1511     [Detail: two cases were found: (a) a repeated subpattern containing an
1512     extended class; (b) a recursive reference to a subpattern that followed a
1513     previous extended class. It wasn't skipping over the extended class
1514     correctly when UTF-8 mode was not set.]
1516     5. A negated single-character class was not being recognized as fixed-length
1517     in lookbehind assertions such as (?<=[^f]), leading to an incorrect
1518     compile error "lookbehind assertion is not fixed length".
1520     6. The RunPerlTest auxiliary script was showing an unexpected difference
1521     between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
1522     write a Perl script that can interpret lines of an input file either as
1523     byte characters or as UTF-8, which is what "perltest" was being required to
1524     do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
1525     can't do is switch easily at run time between having the "use utf8;" pragma
1526     or not. In the end, I fudged it by using the RunPerlTest script to insert
1527     "use utf8;" explicitly for the UTF-8 tests.
1529     7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
1530     the end of the subject string, contrary to the documentation and to what
1531     Perl does. This was true of both matching functions. Now it matches only at
1532     the start of the subject and immediately after *internal* newlines.
1534     8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
1535     a pointer to an int instead of a pointer to an unsigned long int. This
1536     caused problems on 64-bit systems.
1538     9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
1539     instance of the 'standard' template library not being so standard".
1541     10. There was no check on the number of named subpatterns nor the maximum
1542     length of a subpattern name. The product of these values is used to compute
1543     the size of the memory block for a compiled pattern. By supplying a very
1544     long subpattern name and a large number of named subpatterns, the size
1545     computation could be caused to overflow. This is now prevented by limiting
1546     the length of names to 32 characters, and the number of named subpatterns
1547     to 10,000.
1549     11. Subpatterns that are repeated with specific counts have to be replicated in
1550     the compiled pattern. The size of memory for this was computed from the
1551     length of the subpattern and the repeat count. The latter is limited to
1552     65535, but there was no limit on the former, meaning that integer overflow
1553     could in principle occur. The compiled length of a repeated subpattern is
1554     now limited to 30,000 bytes in order to prevent this.
1556     12. Added the optional facility to have named substrings with the same name.
1558     13. Added the ability to use a named substring as a condition, using the
1559     Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
1560     are numbers (not recommended). Forward references are permitted.
1562     14. Added forward references in named backreferences (if you see what I mean).
1564     15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
1565     pattern could run off the end of the subject. For example, the pattern
1566     "(?s)(.{1,5})"8 did this with the subject "ab".
1568     16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
1569     PCRE_CASELESS was set when matching characters that were quantified with ?
1570     or *.
1572     17. A character class other than a single negated character that had a minimum
1573     but no maximum quantifier - for example [ab]{6,} - was not handled
1574     correctly by pce_dfa_exec(). It would match only one character.
1576     18. A valid (though odd) pattern that looked like a POSIX character
1577     class but used an invalid character after [ (for example [[,abc,]]) caused
1578     pcre_compile() to give the error "Failed: internal error: code overflow" or
1579     in some cases to crash with a glibc free() error. This could even happen if
1580     the pattern terminated after [[ but there just happened to be a sequence of
1581     letters, a binary zero, and a closing ] in the memory that followed.
1583     19. Perl's treatment of octal escapes in the range \400 to \777 has changed
1584     over the years. Originally (before any Unicode support), just the bottom 8
1585     bits were taken. Thus, for example, \500 really meant \100. Nowadays the
1586     output from "man perlunicode" includes this:
1588     The regular expression compiler produces polymorphic opcodes. That
1589     is, the pattern adapts to the data and automatically switches to
1590     the Unicode character scheme when presented with Unicode data--or
1591     instead uses a traditional byte scheme when presented with byte
1592     data.
1594     Sadly, a wide octal escape does not cause a switch, and in a string with
1595     no other multibyte characters, these octal escapes are treated as before.
1596     Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern
1597     /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
1598     Unicode string.
1600     I have not perpetrated such confusion in PCRE. Up till now, it took just
1601     the bottom 8 bits, as in old Perl. I have now made octal escapes with
1602     values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
1603     translate to the appropriate multibyte character.
1605     29. Applied some refactoring to reduce the number of warnings from Microsoft
1606     and Borland compilers. This has included removing the fudge introduced
1607     seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
1608     a warning about an unused variable.
1610     21. PCRE has not included VT (character 0x0b) in the set of whitespace
1611     characters since release 4.0, because Perl (from release 5.004) does not.
1612     [Or at least, is documented not to: some releases seem to be in conflict
1613     with the documentation.] However, when a pattern was studied with
1614     pcre_study() and all its branches started with \s, PCRE still included VT
1615     as a possible starting character. Of course, this did no harm; it just
1616     caused an unnecessary match attempt.
1618     22. Removed a now-redundant internal flag bit that recorded the fact that case
1619     dependency changed within the pattern. This was once needed for "required
1620     byte" processing, but is no longer used. This recovers a now-scarce options
1621     bit. Also moved the least significant internal flag bit to the most-
1622     significant bit of the word, which was not previously used (hangover from
1623     the days when it was an int rather than a uint) to free up another bit for
1624     the future.
1626     23. Added support for CRLF line endings as well as CR and LF. As well as the
1627     default being selectable at build time, it can now be changed at runtime
1628     via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
1629     specify that it is scanning data with non-default line endings.
1631     24. Changed the definition of CXXLINK to make it agree with the definition of
1632     LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
1634     25. Applied Ian Taylor's patches to avoid using another stack frame for tail
1635     recursions. This makes a big different to stack usage for some patterns.
1637     26. If a subpattern containing a named recursion or subroutine reference such
1638     as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
1639     the space required for the compiled pattern went wrong and gave too small a
1640     value. Depending on the environment, this could lead to "Failed: internal
1641     error: code overflow at offset 49" or "glibc detected double free or
1642     corruption" errors.
1644     27. Applied patches from Google (a) to support the new newline modes and (b) to
1645     advance over multibyte UTF-8 characters in GlobalReplace.
1647     28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
1648     difference for some implementation of PCRE in some Windows version.
1650     29. Added some extra testing facilities to pcretest:
1652     \q<number> in a data line sets the "match limit" value
1653     \Q<number> in a data line sets the "match recursion limt" value
1654     -S <number> sets the stack size, where <number> is in megabytes
1656     The -S option isn't available for Windows.
1659 nigel 89 Version 6.6 06-Feb-06
1660     ---------------------
1662     1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
1663     in pcreposix.h. I have copied the definition from pcre.h.
1665     2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
1666     because pcre.h is no longer a built file.
1668     3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
1669     not normally included in the compiled code.
1672 nigel 87 Version 6.5 01-Feb-06
1673     ---------------------
1675     1. When using the partial match feature with pcre_dfa_exec(), it was not
1676     anchoring the second and subsequent partial matches at the new starting
1677     point. This could lead to incorrect results. For example, with the pattern
1678     /1234/, partially matching against "123" and then "a4" gave a match.
1680     2. Changes to pcregrep:
1682     (a) All non-match returns from pcre_exec() were being treated as failures
1683     to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
1684     error message is output. Some extra information is given for the
1686     probably the only errors that are likely to be caused by users (by
1687     specifying a regex that has nested indefinite repeats, for instance).
1688     If there are more than 20 of these errors, pcregrep is abandoned.
1690     (b) A binary zero was treated as data while matching, but terminated the
1691     output line if it was written out. This has been fixed: binary zeroes
1692     are now no different to any other data bytes.
1694     (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
1695     used to set a locale for matching. The --locale=xxxx long option has
1696     been added (no short equivalent) to specify a locale explicitly on the
1697     pcregrep command, overriding the environment variables.
1699     (d) When -B was used with -n, some line numbers in the output were one less
1700     than they should have been.
1702     (e) Added the -o (--only-matching) option.
1704     (f) If -A or -C was used with -c (count only), some lines of context were
1705     accidentally printed for the final match.
1707     (g) Added the -H (--with-filename) option.
1709     (h) The combination of options -rh failed to suppress file names for files
1710     that were found from directory arguments.
1712     (i) Added the -D (--devices) and -d (--directories) options.
1714     (j) Added the -F (--fixed-strings) option.
1716     (k) Allow "-" to be used as a file name for -f as well as for a data file.
1718     (l) Added the --colo(u)r option.
1720     (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
1721     is not present by default.
1723     3. A nasty bug was discovered in the handling of recursive patterns, that is,
1724     items such as (?R) or (?1), when the recursion could match a number of
1725     alternatives. If it matched one of the alternatives, but subsequently,
1726     outside the recursion, there was a failure, the code tried to back up into
1727     the recursion. However, because of the way PCRE is implemented, this is not
1728     possible, and the result was an incorrect result from the match.
1730     In order to prevent this happening, the specification of recursion has
1731     been changed so that all such subpatterns are automatically treated as
1732     atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
1734     4. I had overlooked the fact that, in some locales, there are characters for
1735     which isalpha() is true but neither isupper() nor islower() are true. In
1736     the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
1737     and ordfeminine) are like this. This affected the treatment of \w and \W
1738     when they appeared in character classes, but not when they appeared outside
1739     a character class. The bit map for "word" characters is now created
1740     separately from the results of isalnum() instead of just taking it from the
1741     upper, lower, and digit maps. (Plus the underscore character, of course.)
1743     5. The above bug also affected the handling of POSIX character classes such as
1744     [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
1745     permanent tables. Instead, the bit maps for such a class were previously
1746     created as the appropriate unions of the upper, lower, and digit bitmaps.
1747     Now they are created by subtraction from the [[:word:]] class, which has
1748     its own bitmap.
1750     6. The [[:blank:]] character class matches horizontal, but not vertical space.
1751     It is created by subtracting the vertical space characters (\x09, \x0a,
1752     \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
1753     subtraction was done in the overall bitmap for a character class, meaning
1754     that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
1755     be recognized. This bug has been fixed.
1757     7. Patches from the folks at Google:
1759     (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
1760     real life, but is still worth protecting against".
1762     (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
1763     regular expressions".
1765     (c) pcre_scanner.cc: avoid use of std::count() because not all systems
1766     have it.
1768     (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
1769     "configure" and the latter not, in order to fix a problem somebody had
1770     with compiling the Arg class on HP-UX.
1772     (e) Improve the error-handling of the C++ wrapper a little bit.
1774     (f) New tests for checking recursion limiting.
1776     8. The pcre_memmove() function, which is used only if the environment does not
1777     have a standard memmove() function (and is therefore rarely compiled),
1778     contained two bugs: (a) use of int instead of size_t, and (b) it was not
1779     returning a result (though PCRE never actually uses the result).
1781     9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
1782     large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
1783     returned instead of calling malloc() with an overflowing number that would
1784     most likely cause subsequent chaos.
1786     10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
1788     11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
1789     with this option is matched, the nmatch and pmatch options of regexec() are
1790     ignored.
1792     12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
1793     provided in case anyone wants to the the POSIX interface with UTF-8
1794     strings.
1796     13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
1797     C++ linking (needed for some HP-UX environments).
1799     14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
1800     (unused parameter) and in the pcre_printint() function (omitted "default"
1801     switch label when the default is to do nothing).
1803     15. Added some code to make it possible, when PCRE is compiled as a C++
1804     library, to replace subject pointers for pcre_exec() with a smart pointer
1805     class, thus making it possible to process discontinuous strings.
1807     16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
1808     much the same function. They were added by different people who were trying
1809     to make PCRE easy to compile on non-Unix systems. It has been suggested
1810     that PCRE_EXPORT be abolished now that there is more automatic apparatus
1811     for compiling on Windows systems. I have therefore replaced it with
1812     PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
1813     defaults to "extern" for C or "extern C" for C++, which works fine on
1814     Unix-like systems. It is now possible to override the value of PCRE_DATA_
1815     SCOPE with something explicit in config.h. In addition:
1817     (a) pcreposix.h still had just "extern" instead of either of these macros;
1818     I have replaced it with PCRE_DATA_SCOPE.
1820     (b) Functions such as _pcre_xclass(), which are internal to the library,
1821     but external in the C sense, all had PCRE_EXPORT in their definitions.
1822     This is apparently wrong for the Windows case, so I have removed it.
1823     (It makes no difference on Unix-like systems.)
1825     17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
1826     of recursive calls to match(). This is different to MATCH_LIMIT because
1827     that limits the total number of calls to match(), not all of which increase
1828     the depth of recursion. Limiting the recursion depth limits the amount of
1829     stack (or heap if NO_RECURSE is set) that is used. The default can be set
1830     when PCRE is compiled, and changed at run time. A patch from Google adds
1831     this functionality to the C++ interface.
1833     18. Changes to the handling of Unicode character properties:
1835     (a) Updated the table to Unicode 4.1.0.
1837     (b) Recognize characters that are not in the table as "Cn" (undefined).
1839     (c) I revised the way the table is implemented to a much improved format
1840     which includes recognition of ranges. It now supports the ranges that
1841     are defined in UnicodeData.txt, and it also amalgamates other
1842     characters into ranges. This has reduced the number of entries in the
1843     table from around 16,000 to around 3,000, thus reducing its size
1844     considerably. I realized I did not need to use a tree structure after
1845     all - a binary chop search is just as efficient. Having reduced the
1846     number of entries, I extended their size from 6 bytes to 8 bytes to
1847     allow for more data.
1849     (d) Added support for Unicode script names via properties such as \p{Han}.
1851     19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
1852     matching that character.
1854     20. When matching a repeated Unicode property with a minimum greater than zero,
1855     (for example \pL{2,}), PCRE could look past the end of the subject if it
1856     reached it while seeking the minimum number of characters. This could
1857     happen only if some of the characters were more than one byte long, because
1858     there is a check for at least the minimum number of bytes.
1860     21. Refactored the implementation of \p and \P so as to be more general, to
1861     allow for more different types of property in future. This has changed the
1862     compiled form incompatibly. Anybody with saved compiled patterns that use
1863     \p or \P will have to recompile them.
1865     22. Added "Any" and "L&" to the supported property types.
1867     23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
1868     but give a compile time error if the value is greater than 0xff.
1870     24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
1871     accidentally not being installed or uninstalled.
1873     25. The pcre.h file was built from pcre.h.in, but the only changes that were
1874     made were to insert the current release number. This seemed silly, because
1875     it made things harder for people building PCRE on systems that don't run
1876     "configure". I have turned pcre.h into a distributed file, no longer built
1877     by "configure", with the version identification directly included. There is
1878     no longer a pcre.h.in file.
1880     However, this change necessitated a change to the pcre-config script as
1881     well. It is built from pcre-config.in, and one of the substitutions was the
1882     release number. I have updated configure.ac so that ./configure now finds
1883     the release number by grepping pcre.h.
1885     26. Added the ability to run the tests under valgrind.
1888 nigel 85 Version 6.4 05-Sep-05
1889     ---------------------
1891     1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
1892     "--" to be printed when multiple files were scanned, even when none of the
1893     -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
1894     consider it to be a bug, and have restored the previous behaviour.
1896     2. A couple of code tidies to get rid of compiler warnings.
1898     3. The pcretest program used to cheat by referring to symbols in the library
1899     whose names begin with _pcre_. These are internal symbols that are not
1900     really supposed to be visible externally, and in some environments it is
1901     possible to suppress them. The cheating is now confined to including
1902     certain files from the library's source, which is a bit cleaner.
1904     4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
1905     file's purpose clearer.
1907     5. Reorganized pcre_ucp_findchar().
1910 nigel 83 Version 6.3 15-Aug-05
1911     ---------------------
1913     1. The file libpcre.pc.in did not have general read permission in the tarball.
1915     2. There were some problems when building without C++ support:
1917     (a) If C++ support was not built, "make install" and "make test" still
1918     tried to test it.
1920     (b) There were problems when the value of CXX was explicitly set. Some
1921     changes have been made to try to fix these, and ...
1923     (c) --disable-cpp can now be used to explicitly disable C++ support.
1925     (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
1926     backslash in a target when C++ was disabled. This confuses some
1927     versions of "make", apparently. Using an intermediate variable solves
1928     this. (Same for CPP_LOBJ.)
1930     3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
1931     (non-Windows) now includes $(CFLAGS) because these flags are sometimes
1932     necessary on certain architectures.
1934     4. Added a setting of -export-symbols-regex to the link command to remove
1935     those symbols that are exported in the C sense, but actually are local
1936     within the library, and not documented. Their names all begin with
1937     "_pcre_". This is not a perfect job, because (a) we have to except some
1938     symbols that pcretest ("illegally") uses, and (b) the facility isn't always
1939     available (and never for static libraries). I have made a note to try to
1940     find a way round (a) in the future.
1943 nigel 81 Version 6.2 01-Aug-05
1944     ---------------------
1946     1. There was no test for integer overflow of quantifier values. A construction
1947     such as {1111111111111111} would give undefined results. What is worse, if
1948     a minimum quantifier for a parenthesized subpattern overflowed and became
1949     negative, the calculation of the memory size went wrong. This could have
1950     led to memory overwriting.
1952     2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
1954     3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
1955     operating environments where this matters.
1957     4. Applied Giuseppe Maxia's patch to add additional features for controlling
1958     PCRE options from within the C++ wrapper.
1960     5. Named capturing subpatterns were not being correctly counted when a pattern
1961     was compiled. This caused two problems: (a) If there were more than 100
1962     such subpatterns, the calculation of the memory needed for the whole
1963     compiled pattern went wrong, leading to an overflow error. (b) Numerical
1964     back references of the form \12, where the number was greater than 9, were
1965     not recognized as back references, even though there were sufficient
1966     previous subpatterns.
1968     6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
1969     versions of gcc, e.g. 2.95.4.
1972 nigel 79 Version 6.1 21-Jun-05
1973     ---------------------
1975     1. There was one reference to the variable "posix" in pcretest.c that was not
1976     surrounded by "#if !defined NOPOSIX".
1978     2. Make it possible to compile pcretest without DFA support, UTF8 support, or
1979     the cross-check on the old pcre_info() function, for the benefit of the
1980     cut-down version of PCRE that is currently imported into Exim.
1982     3. A (silly) pattern starting with (?i)(?-i) caused an internal space
1983     allocation error. I've done the easy fix, which wastes 2 bytes for sensible
1984     patterns that start (?i) but I don't think that matters. The use of (?i) is
1985     just an example; this all applies to the other options as well.
1987     4. Since libtool seems to echo the compile commands it is issuing, the output
1988     from "make" can be reduced a bit by putting "@" in front of each libtool
1989     compile command.
1991     5. Patch from the folks at Google for configure.in to be a bit more thorough
1992     in checking for a suitable C++ installation before trying to compile the
1993     C++ stuff. This should fix a reported problem when a compiler was present,
1994     but no suitable headers.
1996     6. The man pages all had just "PCRE" as their title. I have changed them to
1997     be the relevant file name. I have also arranged that these names are
1998     retained in the file doc/pcre.txt, which is a concatenation in text format
1999     of all the man pages except the little individual ones for each function.
2001     7. The NON-UNIX-USE file had not been updated for the different set of source
2002     files that come with release 6. I also added a few comments about the C++
2003     wrapper.
2006 nigel 77 Version 6.0 07-Jun-05
2007     ---------------------
2009     1. Some minor internal re-organization to help with my DFA experiments.
2011     2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
2012     didn't matter for the library itself when fully configured, but did matter
2013     when compiling without UCP support, or within Exim, where the ucp files are
2014     not imported.
2016     3. Refactoring of the library code to split up the various functions into
2017     different source modules. The addition of the new DFA matching code (see
2018     below) to a single monolithic source would have made it really too
2019     unwieldy, quite apart from causing all the code to be include in a
2020     statically linked application, when only some functions are used. This is
2021     relevant even without the DFA addition now that patterns can be compiled in
2022     one application and matched in another.
2024     The downside of splitting up is that there have to be some external
2025     functions and data tables that are used internally in different modules of
2026     the library but which are not part of the API. These have all had their
2027     names changed to start with "_pcre_" so that they are unlikely to clash
2028     with other external names.
2030     4. Added an alternate matching function, pcre_dfa_exec(), which matches using
2031     a different (DFA) algorithm. Although it is slower than the original
2032     function, it does have some advantages for certain types of matching
2033     problem.
2035     5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
2036     including restarting after a partial match.
2038     6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
2039     defined when compiling for Windows was sent to me. I have put it into the
2040     code, though I have no means of testing or verifying it.
2042     7. Added the pcre_refcount() auxiliary function.
2044     8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
2045     match before or at the first newline in the subject string. In pcretest,
2046     the /f option on a pattern can be used to set this.
2048     9. A repeated \w when used in UTF-8 mode with characters greater than 256
2049     would behave wrongly. This has been present in PCRE since release 4.0.
2051     10. A number of changes to the pcregrep command:
2053     (a) Refactored how -x works; insert ^(...)$ instead of setting
2054     PCRE_ANCHORED and checking the length, in preparation for adding
2055     something similar for -w.
2057     (b) Added the -w (match as a word) option.
2059     (c) Refactored the way lines are read and buffered so as to have more
2060     than one at a time available.
2062     (d) Implemented a pcregrep test script.
2064     (e) Added the -M (multiline match) option. This allows patterns to match
2065     over several lines of the subject. The buffering ensures that at least
2066     8K, or the rest of the document (whichever is the shorter) is available
2067     for matching (and similarly the previous 8K for lookbehind assertions).
2069     (f) Changed the --help output so that it now says
2071     -w, --word-regex(p)
2073     instead of two lines, one with "regex" and the other with "regexp"
2074     because that confused at least one person since the short forms are the
2075     same. (This required a bit of code, as the output is generated
2076     automatically from a table. It wasn't just a text change.)
2078     (g) -- can be used to terminate pcregrep options if the next thing isn't an
2079     option but starts with a hyphen. Could be a pattern or a path name
2080     starting with a hyphen, for instance.
2082     (h) "-" can be given as a file name to represent stdin.
2084     (i) When file names are being printed, "(standard input)" is used for
2085     the standard input, for compatibility with GNU grep. Previously
2086     "<stdin>" was used.
2088     (j) The option --label=xxx can be used to supply a name to be used for
2089     stdin when file names are being printed. There is no short form.
2091     (k) Re-factored the options decoding logic because we are going to add
2092     two more options that take data. Such options can now be given in four
2093     different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
2095     (l) Added the -A, -B, and -C options for requesting that lines of context
2096     around matches be printed.
2098     (m) Added the -L option to print the names of files that do not contain
2099     any matching lines, that is, the complement of -l.
2101     (n) The return code is 2 if any file cannot be opened, but pcregrep does
2102     continue to scan other files.
2104     (o) The -s option was incorrectly implemented. For compatibility with other
2105     greps, it now suppresses the error message for a non-existent or non-
2106     accessible file (but not the return code). There is a new option called
2107     -q that suppresses the output of matching lines, which was what -s was
2108     previously doing.
2110     (p) Added --include and --exclude options to specify files for inclusion
2111     and exclusion when recursing.
2113     11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
2114     Hopefully, it now does.
2116     12. Missing cast in pcre_study().
2118     13. Added an "uninstall" target to the makefile.
2120     14. Replaced "extern" in the function prototypes in Makefile.in with
2121     "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
2122     world, but is set differently for Windows.
2124     15. Added a second compiling function called pcre_compile2(). The only
2125     difference is that it has an extra argument, which is a pointer to an
2126     integer error code. When there is a compile-time failure, this is set
2127     non-zero, in addition to the error test pointer being set to point to an
2128     error message. The new argument may be NULL if no error number is required
2129     (but then you may as well call pcre_compile(), which is now just a
2130     wrapper). This facility is provided because some applications need a
2131     numeric error indication, but it has also enabled me to tidy up the way
2132     compile-time errors are handled in the POSIX wrapper.
2134     16. Added VPATH=.libs to the makefile; this should help when building with one
2135     prefix path and installing with another. (Or so I'm told by someone who
2136     knows more about this stuff than I do.)
2138     17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
2139     passes PCRE_DOTALL to the pcre_compile() function, making the "." character
2140     match everything, including newlines. This is not POSIX-compatible, but
2141     somebody wanted the feature. From pcretest it can be activated by using
2142     both the P and the s flags.
2144     18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
2146     19. libpcre.pc was being incorrectly installed as executable.
2148     20. A couple of places in pcretest check for end-of-line by looking for '\n';
2149     it now also looks for '\r' so that it will work unmodified on Windows.
2151     21. Added Google's contributed C++ wrapper to the distribution.
2153     22. Added some untidy missing memory free() calls in pcretest, to keep
2154     Electric Fence happy when testing.
2158 nigel 75 Version 5.0 13-Sep-04
2159     ---------------------
2161     1. Internal change: literal characters are no longer packed up into items
2162     containing multiple characters in a single byte-string. Each character
2163     is now matched using a separate opcode. However, there may be more than one
2164     byte in the character in UTF-8 mode.
2166     2. The pcre_callout_block structure has two new fields: pattern_position and
2167     next_item_length. These contain the offset in the pattern to the next match
2168     item, and its length, respectively.
2170     3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
2171     insertion of callouts before each pattern item. Added the /C option to
2172     pcretest to make use of this.
2174     4. On the advice of a Windows user, the lines
2176     #if defined(_WIN32) || defined(WIN32)
2177     _setmode( _fileno( stdout ), 0x8000 );
2178     #endif /* defined(_WIN32) || defined(WIN32) */
2180     have been added to the source of pcretest. This apparently does useful
2181     magic in relation to line terminators.
2183     5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
2184     for the benefit of those environments where the "b" makes a difference.
2186     6. The icc compiler has the same options as gcc, but "configure" doesn't seem
2187     to know about it. I have put a hack into configure.in that adds in code
2188     to set GCC=yes if CC=icc. This seems to end up at a point in the
2189     generated configure script that is early enough to affect the setting of
2190     compiler options, which is what is needed, but I have no means of testing
2191     whether it really works. (The user who reported this had patched the
2192     generated configure script, which of course I cannot do.)
2194     LATER: After change 22 below (new libtool files), the configure script
2195     seems to know about icc (and also ecc). Therefore, I have commented out
2196     this hack in configure.in.
2198     7. Added support for pkg-config (2 patches were sent in).
2200     8. Negated POSIX character classes that used a combination of internal tables
2201     were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
2202     [[:^ascii]]. Typically, they would match almost any characters. The other
2203     POSIX classes were not broken in this way.
2205     9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
2206     to find the match, as PCRE was deluded into thinking that the match had to
2207     start at the start point or following a newline. The same bug applied to
2208     patterns with negative forward assertions or any backward assertions
2209     preceding ".*" at the start, unless the pattern required a fixed first
2210     character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
2212     10. In UTF-8 mode, when moving forwards in the subject after a failed match
2213     starting at the last subject character, bytes beyond the end of the subject
2214     string were read.
2216     11. Renamed the variable "class" as "classbits" to make life easier for C++
2217     users. (Previously there was a macro definition, but it apparently wasn't
2218     enough.)
2220     12. Added the new field "tables" to the extra data so that tables can be passed
2221     in at exec time, or the internal tables can be re-selected. This allows
2222     a compiled regex to be saved and re-used at a later time by a different
2223     program that might have everything at different addresses.
2225     13. Modified the pcre-config script so that, when run on Solaris, it shows a
2226     -R library as well as a -L library.
2228     14. The debugging options of pcretest (-d on the command line or D on a
2229     pattern) showed incorrect output for anything following an extended class
2230     that contained multibyte characters and which was followed by a quantifier.
2232     15. Added optional support for general category Unicode character properties
2233     via the \p, \P, and \X escapes. Unicode property support implies UTF-8
2234     support. It adds about 90K to the size of the library. The meanings of the
2235     inbuilt class escapes such as \d and \s have NOT been changed.
2237     16. Updated pcredemo.c to include calls to free() to release the memory for the
2238     compiled pattern.
2240     17. The generated file chartables.c was being created in the source directory
2241     instead of in the building directory. This caused the build to fail if the
2242     source directory was different from the building directory, and was
2243     read-only.
2245     18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
2246     file. No doubt somebody will tell me if they don't make sense... Also added
2247     Dan Mooney's comments about building on OpenVMS.
2249     19. Added support for partial matching via the PCRE_PARTIAL option for
2250     pcre_exec() and the \P data escape in pcretest.
2252     20. Extended pcretest with 3 new pattern features:
2254     (i) A pattern option of the form ">rest-of-line" causes pcretest to
2255     write the compiled pattern to the file whose name is "rest-of-line".
2256     This is a straight binary dump of the data, with the saved pointer to
2257     the character tables forced to be NULL. The study data, if any, is
2258     written too. After writing, pcretest reads a new pattern.
2260     (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
2261     compiled pattern from the given file. There must not be any
2262     occurrences of "<" in the file name (pretty unlikely); if there are,
2263     pcretest will instead treat the initial "<" as a pattern delimiter.
2264     After reading in the pattern, pcretest goes on to read data lines as
2265     usual.
2267     (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
2268     and 16-bit fields in a compiled pattern, to simulate a pattern that
2269     was compiled on a host of opposite endianness.
2271     21. The pcre-exec() function can now cope with patterns that were compiled on
2272     hosts of opposite endianness, with this restriction:
2274     As for any compiled expression that is saved and used later, the tables
2275     pointer field cannot be preserved; the extra_data field in the arguments
2276     to pcre_exec() should be used to pass in a tables address if a value
2277     other than the default internal tables were used at compile time.
2279     22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
2280     now diagnosed as an error. Previously, most of the time, a negative number
2281     would have been treated as zero, but if in addition "ovector" was passed as
2282     NULL, a crash could occur.
2284     23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
2285     new versions from the libtool 1.5 distribution (the last one is a copy of
2286     a file called libtool.m4). This seems to have fixed the need to patch
2287     "configure" to support Darwin 1.3 (which I used to do). However, I still
2288     had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
2289     workstation).
2291     24. Changed the PCRE licence to be the more standard "BSD" licence.
2294 nigel 73 Version 4.5 01-Dec-03
2295     ---------------------
2297     1. There has been some re-arrangement of the code for the match() function so
2298     that it can be compiled in a version that does not call itself recursively.
2299     Instead, it keeps those local variables that need separate instances for
2300     each "recursion" in a frame on the heap, and gets/frees frames whenever it
2301     needs to "recurse". Keeping track of where control must go is done by means
2302     of setjmp/longjmp. The whole thing is implemented by a set of macros that
2303     hide most of the details from the main code, and operates only if
2304     NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
2305     "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
2306     operating.
2308     To make it easier for callers to provide specially tailored get/free
2309     functions for this usage, two new functions, pcre_stack_malloc, and
2310     pcre_stack_free, are used. They are always called in strict stacking order,
2311     and the size of block requested is always the same.
2313     The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
2314     PCRE has been compiled to use the stack or the heap for recursion. The
2315     -C option of pcretest uses this to show which version is compiled.
2317     A new data escape \S, is added to pcretest; it causes the amounts of store
2318     obtained and freed by both kinds of malloc/free at match time to be added
2319     to the output.
2321     2. Changed the locale test to use "fr_FR" instead of "fr" because that's
2322     what's available on my current Linux desktop machine.
2324     3. When matching a UTF-8 string, the test for a valid string at the start has
2325     been extended. If start_offset is not zero, PCRE now checks that it points
2326     to a byte that is the start of a UTF-8 character. If not, it returns
2327     PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
2328     this is necessary because there may be backward assertions in the pattern.
2329     When matching the same subject several times, it may save resources to use
2330     PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
2332     4. The code for checking the validity of UTF-8 strings has been tightened so
2333     that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
2334     containing "overlong sequences".
2336     5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
2337     I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
2338     should have been "&", but it just so happened that all the cases this let
2339     through by mistake were picked up later in the function.
2341     6. I had used a variable called "isblank" - this is a C99 function, causing
2342     some compilers to warn. To avoid this, I renamed it (as "blankclass").
2344     7. Cosmetic: (a) only output another newline at the end of pcretest if it is
2345     prompting; (b) run "./pcretest /dev/null" at the start of the test script
2346     so the version is shown; (c) stop "make test" echoing "./RunTest".
2348     8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
2350     9. The prototype for memmove() for systems that don't have it was using
2351     size_t, but the inclusion of the header that defines size_t was later. I've
2352     moved the #includes for the C headers earlier to avoid this.
2354     10. Added some adjustments to the code to make it easier to compiler on certain
2355     special systems:
2357     (a) Some "const" qualifiers were missing.
2358     (b) Added the macro EXPORT before all exported functions; by default this
2359     is defined to be empty.
2360     (c) Changed the dftables auxiliary program (that builds chartables.c) so
2361     that it reads its output file name as an argument instead of writing
2362     to the standard output and assuming this can be redirected.
2364     11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
2365     class containing characters with values greater than 255, PCRE compilation
2366     went into a loop.
2368     12. A recursive reference to a subpattern that was within another subpattern
2369     that had a minimum quantifier of zero caused PCRE to crash. For example,
2370     (x(y(?2))z)? provoked this bug with a subject that got as far as the
2371     recursion. If the recursively-called subpattern itself had a zero repeat,
2372     that was OK.
2374     13. In pcretest, the buffer for reading a data line was set at 30K, but the
2375     buffer into which it was copied (for escape processing) was still set at
2376     1024, so long lines caused crashes.
2378     14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
2379     "internal error: code overflow...". This applied to any character class
2380     that was followed by a possessive quantifier.
2382     15. Modified the Makefile to add libpcre.la as a prerequisite for
2383     libpcreposix.la because I was told this is needed for a parallel build to
2384     work.
2386     16. If a pattern that contained .* following optional items at the start was
2387     studied, the wrong optimizing data was generated, leading to matching
2388     errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
2389     matching string must start with a or b or c. The correct conclusion for
2390     this pattern is that a match can start with any character.
2393 nigel 71 Version 4.4 13-Aug-03
2394     ---------------------
2396     1. In UTF-8 mode, a character class containing characters with values between
2397     127 and 255 was not handled correctly if the compiled pattern was studied.
2398     In fixing this, I have also improved the studying algorithm for such
2399     classes (slightly).
2401     2. Three internal functions had redundant arguments passed to them. Removal
2402     might give a very teeny performance improvement.
2404     3. Documentation bug: the value of the capture_top field in a callout is *one
2405     more than* the number of the hightest numbered captured substring.
2407     4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
2408     in incorrectly linking with a previously installed version. They now link
2409     explicitly with libpcre.la.
2411     5. configure.in no longer needs to recognize Cygwin specially.
2413     6. A problem in pcre.in for Windows platforms is fixed.
2415     7. If a pattern was successfully studied, and the -d (or /D) flag was given to
2416     pcretest, it used to include the size of the study block as part of its
2417     output. Unfortunately, the structure contains a field that has a different
2418     size on different hardware architectures. This meant that the tests that
2419     showed this size failed. As the block is currently always of a fixed size,
2420     this information isn't actually particularly useful in pcretest output, so
2421     I have just removed it.
2423     8. Three pre-processor statements accidentally did not start in column 1.
2424     Sadly, there are *still* compilers around that complain, even though
2425     standard C has not required this for well over a decade. Sigh.
2427     9. In pcretest, the code for checking callouts passed small integers in the
2428     callout_data field, which is a void * field. However, some picky compilers
2429     complained about the casts involved for this on 64-bit systems. Now
2430     pcretest passes the address of the small integer instead, which should get
2431     rid of the warnings.
2433     10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
2434     both compile and run time, and gives an error if an invalid UTF-8 sequence
2435     is found. There is a option for disabling this check in cases where the
2436     string is known to be correct and/or the maximum performance is wanted.
2438     11. In response to a bug report, I changed one line in Makefile.in from
2440     -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
2441     to
2442     -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
2444     to look similar to other lines, but I have no way of telling whether this
2445     is the right thing to do, as I do not use Windows. No doubt I'll get told
2446     if it's wrong...
2449 nigel 69 Version 4.3 21-May-03
2450     ---------------------
2452     1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
2453     Makefile.
2455     2. Some refactoring to improve the quality of the code:
2457     (i) The utf8_table... variables are now declared "const".
2459     (ii) The code for \cx, which used the "case flipping" table to upper case
2460     lower case letters, now just substracts 32. This is ASCII-specific,
2461     but the whole concept of \cx is ASCII-specific, so it seems
2462     reasonable.
2464     (iii) PCRE was using its character types table to recognize decimal and
2465     hexadecimal digits in the pattern. This is silly, because it handles
2466     only 0-9, a-f, and A-F, but the character types table is locale-
2467     specific, which means strange things might happen. A private
2468     table is now used for this - though it costs 256 bytes, a table is
2469     much faster than multiple explicit tests. Of course, the standard
2470     character types table is still used for matching digits in subject
2471     strings against \d.
2473     (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
2474     ending in _t are). So I've renamed it as ESC_tee.
2476     3. The first argument for regexec() in the POSIX wrapper should have been
2477     defined as "const".
2479     4. Changed pcretest to use malloc() for its buffers so that they can be
2480     Electric Fenced for debugging.
2482     5. There were several places in the code where, in UTF-8 mode, PCRE would try
2483     to read one or more bytes before the start of the subject string. Often this
2484     had no effect on PCRE's behaviour, but in some circumstances it could
2485     provoke a segmentation fault.
2487     6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
2488     to try to read one or more bytes before the start of the subject string.
2490     7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
2491     UTF-8 support could misbehave in various ways if the subject string
2492     contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
2493     area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
2494     back over UTF-8 characters.)
2497 nigel 67 Version 4.2 14-Apr-03
2498     ---------------------
2500     1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
2502     2. Changes to the building process, supplied by Ronald Landheer-Cieslak
2503     [ON_WINDOWS]: new variable, "#" on non-Windows platforms
2504     [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
2505     [WIN_PREFIX]: new variable, "cyg" for Cygwin
2506     * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
2507     and BUILD_EXEEXT
2508     Note: automatic setting of the BUILD variables is not yet working
2509     set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
2510     compile-time but not at link-time
2511     [LINK]: use for linking executables only
2512     make different versions for Windows and non-Windows
2513     [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
2514     libraries
2515     [LINK_FOR_BUILD]: new variable
2516     [OBJEXT]: use throughout
2517     [EXEEXT]: use throughout
2518     <winshared>: new target
2519     <wininstall>: new target
2520     <dftables.o>: use native compiler
2521     <dftables>: use native linker
2522     <install>: handle Windows platform correctly
2523     <clean>: ditto
2524     <check>: ditto
2525     copy DLL to top builddir before testing
2527     As part of these changes, -no-undefined was removed again. This was reported
2528     to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
2529     in any case.
2531     3. Some tidies to get rid of compiler warnings:
2533     . In the match_data structure, match_limit was an unsigned long int, whereas
2534     match_call_count was an int. I've made them both unsigned long ints.
2536     . In pcretest the fact that a const uschar * doesn't automatically cast to
2537     a void * provoked a warning.
2539     . Turning on some more compiler warnings threw up some "shadow" variables
2540     and a few more missing casts.
2542     4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
2543     option, a class that contained a single character with a value between 128
2544     and 255 (e.g. /[\xFF]/) caused PCRE to crash.
2546     5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
2547     option, a class that contained several characters, but with at least one
2548     whose value was between 128 and 255 caused PCRE to crash.
2551 nigel 65 Version 4.1 12-Mar-03
2552     ---------------------
2553 nigel 63
2554 nigel 65 1. Compiling with gcc -pedantic found a couple of places where casts were
2555     needed, and a string in dftables.c that was longer than standard compilers are
2556     required to support.
2558     2. Compiling with Sun's compiler found a few more places where the code could
2559     be tidied up in order to avoid warnings.
2561     3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
2562     first of these names is deprecated in the latest Autoconf in favour of the name
2563     CC_FOR_BUILD, because "host" is typically used to mean the system on which the
2564     compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
2565     analogy I have changed it to CFLAGS_FOR_BUILD.
2567     4. Added -no-undefined to the linking command in the Makefile, because this is
2568     apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
2569     linking step for the pcreposix library.
2571     5. PCRE was failing to diagnose the case of two named groups with the same
2572     name.
2574     6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
2575     literal character that is needed in the subject for a match, and scans along to
2576     ensure that it is present before embarking on the full matching process. This
2577     saves time in cases of nested unlimited repeats that are never going to match.
2578     Problem: the scan can take a lot of time if the subject is very long (e.g.
2579     megabytes), thus penalizing straightforward matches. It is now done only if the
2580     amount of subject to be scanned is less than 1000 bytes.
2582     7. A lesser problem with the same optimization is that it was recording the
2583     first character of an anchored pattern as "needed", thus provoking a search
2584     right along the subject, even when the first match of the pattern was going to
2585     fail. The "needed" character is now not set for anchored patterns, unless it
2586     follows something in the pattern that is of non-fixed length. Thus, it still
2587     fulfils its original purpose of finding quick non-matches in cases of nested
2588     unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
2591     Version 4.0 17-Feb-03
2592     ---------------------
2594 nigel 63 1. If a comment in an extended regex that started immediately after a meta-item
2595     extended to the end of string, PCRE compiled incorrect data. This could lead to
2596     all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
2598     2. Moved to autoconf 2.53 and libtool 1.4.2.
2600     3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
2601     the special perltest8 script is no longer needed - all the tests can be run
2602     from a single perltest script.
2604     4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
2605     by \s. It has now been removed in PCRE. This means it isn't recognized as
2606     whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
2607     class [:space:] *does* include VT, thereby creating a mess.
2609     5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
2610     space and tab.
2612     6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
2613     its new features into the main test script, reducing the number of scripts.
2615     7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
2616     were backward compatible, and made the (?i) apply to the whole pattern, as if
2617     /i were given. Now it behaves more logically, and applies the option setting
2618     only to what follows. PCRE has been changed to follow suit. However, if it
2619     finds options settings right at the start of the pattern, it extracts them into
2620     the global options, as before. Thus, they show up in the info data.
2622     8. Added support for the \Q...\E escape sequence. Characters in between are
2623     treated as literals. This is slightly different from Perl in that $ and @ are
2624     also handled as literals inside the quotes. In Perl, they will cause variable
2625     interpolation. Note the following examples:
2627     Pattern PCRE matches Perl matches
2629     \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
2630     \Qabc\$xyz\E abc\$xyz abc\$xyz
2631     \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
2633     For compatibility with Perl, \Q...\E sequences are recognized inside character
2634     classes as well as outside them.
2636     9. Re-organized 3 code statements in pcretest to avoid "overflow in
2637     floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
2638     (size_t) cast to one statement in pcretest and one in pcreposix to avoid
2639     signed/unsigned warnings.
2641     10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
2642     option for pcretest, so I've replaced it by a simple function that does just
2643     that job.
2645     11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
2646     "pcregrep -".
2648     12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
2649     Java package. This provides some syntactic sugar for simple cases of what my
2650     documentation calls "once-only subpatterns". A pattern such as x*+ is the same
2651     as (?>x*). In other words, if what is inside (?>...) is just a single repeated
2652     item, you can use this simplified notation. Note that only makes sense with
2653     greedy quantifiers. Consequently, the use of the possessive quantifier forces
2654     greediness, whatever the setting of the PCRE_UNGREEDY option.
2656     13. A change of greediness default within a pattern was not taking effect at
2657     the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
2658     subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
2659     was abstracted outside.
2661     14. PCRE now supports the \G assertion. It is true when the current matching
2662     position is at the start point of the match. This differs from \A when the
2663     starting offset is non-zero. Used with the /g option of pcretest (or similar
2664     code), it works in the same way as it does for Perl's /g option. If all
2665     alternatives of a regex begin with \G, the expression is anchored to the start
2666     match position, and the "anchored" flag is set in the compiled expression.
2668     15. Some bugs concerning the handling of certain option changes within patterns
2669     have been fixed. These applied to options other than (?ims). For example,
2670     "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
2671     been the other way round. Some of this was related to change 7 above.
2673     16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
2674     features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
2675     and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
2676     POSIX classes only within a class (e.g. /[[:alpha:]]/).
2678     17. Added support for Perl's \C escape. This matches one byte, even in UTF8
2679     mode. Unlike ".", it always matches newline, whatever the setting of
2680     PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
2681     assertions. Perl allows it, but it doesn't (in general) work because it can't
2682     calculate the length of the lookbehind. At least, that's the case for Perl
2683     5.8.0 - I've been told they are going to document that it doesn't work in
2684     future.
2686     18. Added an error diagnosis for escapes that PCRE does not support: these are
2687     \L, \l, \N, \P, \p, \U, \u, and \X.
2689     19. Although correctly diagnosing a missing ']' in a character class, PCRE was
2690     reading past the end of the pattern in cases such as /[abcd/.
2692     20. PCRE was getting more memory than necessary for patterns with classes that
2693     contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
2695     21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
2696     compiling PCRE for use with Virtual Pascal.
2698     22. Small fix to the Makefile to make it work properly if the build is done
2699     outside the source tree.
2701     23. Added a new extension: a condition to go with recursion. If a conditional
2702     subpattern starts with (?(R) the "true" branch is used if recursion has
2703     happened, whereas the "false" branch is used only at the top level.
2705     24. When there was a very long string of literal characters (over 255 bytes
2706     without UTF support, over 250 bytes with UTF support), the computation of how
2707     much memory was required could be incorrect, leading to segfaults or other
2708     strange effects.
2710     25. PCRE was incorrectly assuming anchoring (either to start of subject or to
2711     start of line for a non-DOTALL pattern) when a pattern started with (.*) and
2712     there was a subsequent back reference to those brackets. This meant that, for
2713     example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
2714     possible to check for precisely this case. All we can do is abandon the
2715     optimization if .* occurs inside capturing brackets when there are any back
2716     references whatsoever. (See below for a better fix that came later.)
2718     26. The handling of the optimization for finding the first character of a
2719     non-anchored pattern, and for finding a character that is required later in the
2720     match were failing in some cases. This didn't break the matching; it just
2721     failed to optimize when it could. The way this is done has been re-implemented.
2723     27. Fixed typo in error message for invalid (?R item (it said "(?p").
2725     28. Added a new feature that provides some of the functionality that Perl
2726     provides with (?{...}). The facility is termed a "callout". The way it is done
2727     in PCRE is for the caller to provide an optional function, by setting
2728     pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
2729     global variable. By default it is unset, which disables all calling out. To get
2730     the function called, the regex must include (?C) at appropriate points. This
2731     is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
2732     This provides a means of identifying different callout points. When PCRE
2733     reaches such a point in the regex, if pcre_callout has been set, the external
2734     function is called. It is provided with data in a structure called
2735     pcre_callout_block, which is defined in pcre.h. If the function returns 0,
2736     matching continues; if it returns a non-zero value, the match at the current
2737     point fails. However, backtracking will occur if possible. [This was changed
2738     later and other features added - see item 49 below.]
2740     29. pcretest is upgraded to test the callout functionality. It provides a
2741     callout function that displays information. By default, it shows the start of
2742     the match and the current position in the text. There are some new data escapes
2743     to vary what happens:
2745     \C+ in addition, show current contents of captured substrings
2746     \C- do not supply a callout function
2747     \C!n return 1 when callout number n is reached
2748     \C!n!m return 1 when callout number n is reached for the mth time
2750     30. If pcregrep was called with the -l option and just a single file name, it
2751     output "<stdin>" if a match was found, instead of the file name.
2753     31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
2754     slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
2755     pcre_exec(). This saves a malloc/free per call. The default value of
2756     POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
2757     when configuring.
2759     32. The default maximum size of a compiled pattern is 64K. There have been a
2760     few cases of people hitting this limit. The code now uses macros to handle the
2761     storing of links as offsets within the compiled pattern. It defaults to 2-byte
2762     links, but this can be changed to 3 or 4 bytes by --with-link-size when
2763     configuring. Tests 2 and 5 work only with 2-byte links because they output
2764     debugging information about compiled patterns.
2766     33. Internal code re-arrangements:
2768     (a) Moved the debugging function for printing out a compiled regex into
2769     its own source file (printint.c) and used #include to pull it into
2770     pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
2771     separate copies.
2773     (b) Defined the list of op-code names for debugging as a macro in
2774     internal.h so that it is next to the definition of the opcodes.
2776     (c) Defined a table of op-code lengths for simpler skipping along compiled
2777     code. This is again a macro in internal.h so that it is next to the
2778     definition of the opcodes.
2780     34. Added support for recursive calls to individual subpatterns, along the
2781     lines of Robin Houston's patch (but implemented somewhat differently).
2783     35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
2784     allow it to read and process whole directories in Win32. This code was
2785     contributed by Lionel Fourquaux; it has not been tested by me.
2787     36. Added support for named subpatterns. The Python syntax (?P<name>...) is
2788     used to name a group. Names consist of alphanumerics and underscores, and must
2789     be unique. Back references use the syntax (?P=name) and recursive calls use
2790     (?P>name) which is a PCRE extension to the Python extension. Groups still have
2791     numbers. The function pcre_fullinfo() can be used after compilation to extract
2792     a name/number map. There are three relevant calls:
2794     PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
2795     PCRE_INFO_NAMECOUNT yields the number of entries
2796     PCRE_INFO_NAMETABLE yields a pointer to the map.
2798     The map is a vector of fixed-size entries. The size of each entry depends on
2799     the length of the longest name used. The first two bytes of each entry are the
2800     group number, most significant byte first. There follows the corresponding
2801     name, zero terminated. The names are in alphabetical order.
2803     37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
2804     case instead of 255. Making it the same both with and without UTF-8 support
2805     means that the same test output works with both.
2807     38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
2808     calling malloc() with a zero argument.
2810     39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
2811     optimization. I've improved things by keeping a bitmap of backreferences with
2812     numbers 1-31 so that if .* occurs inside capturing brackets that are not in
2813     fact referenced, the optimization can be applied. It is unlikely that a
2814     relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
2815     the match to follow \n) will appear inside brackets with a number greater than
2816     31, but if it does, any back reference > 31 suppresses the optimization.
2818     40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
2819     of disabling numbered capturing parentheses. Any opening parenthesis that is
2820     not followed by ? behaves as if it were followed by ?: but named parentheses
2821     can still be used for capturing (and they will acquire numbers in the usual
2822     way).
2824     41. Redesigned the return codes from the match() function into yes/no/error so
2825     that errors can be passed back from deep inside the nested calls. A malloc
2826     failure while inside a recursive subpattern call now causes the
2827     PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
2829     42. It is now possible to set a limit on the number of times the match()
2830     function is called in a call to pcre_exec(). This facility makes it possible to
2831     limit the amount of recursion and backtracking, though not in a directly
2832     obvious way, because the match() function is used in a number of different
2833     circumstances. The count starts from zero for each position in the subject
2834     string (for non-anchored patterns). The default limit is, for compatibility, a
2835     large number, namely 10 000 000. You can change this in two ways:
2837     (a) When configuring PCRE before making, you can use --with-match-limit=n
2838     to set a default value for the compiled library.
2840     (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
2841     a different value is set. See 45 below.
2843     If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
2845     43. Added a new function pcre_config(int, void *) to enable run-time extraction
2846     of things that can be changed at compile time. The first argument specifies
2847     what is wanted and the second points to where the information is to be placed.
2848     The current list of available information is:
2852     The output is an integer that is set to one if UTF-8 support is available;
2853     otherwise it is set to zero.
2857     The output is an integer that it set to the value of the code that is used for
2858     newline. It is either LF (10) or CR (13).
2862     The output is an integer that contains the number of bytes used for internal
2863     linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
2867     The output is an integer that contains the threshold above which the POSIX
2868     interface uses malloc() for output vectors. See item 31 above.
2872     The output is an unsigned integer that contains the default limit of the number
2873     of match() calls in a pcre_exec() execution. See 42 above.
2875     44. pcretest has been upgraded by the addition of the -C option. This causes it
2876     to extract all the available output from the new pcre_config() function, and to
2877     output it. The program then exits immediately.
2879     45. A need has arisen to pass over additional data with calls to pcre_exec() in
2880     order to support additional features. One way would have been to define
2881     pcre_exec2() (for example) with extra arguments, but this would not have been
2882     extensible, and would also have required all calls to the original function to
2883     be mapped to the new one. Instead, I have chosen to extend the mechanism that
2884     is used for passing in "extra" data from pcre_study().
2886     The pcre_extra structure is now exposed and defined in pcre.h. It currently
2887     contains the following fields:
2889     flags a bitmap indicating which of the following fields are set
2890     study_data opaque data from pcre_study()
2891     match_limit a way of specifying a limit on match() calls for a specific
2892     call to pcre_exec()
2893     callout_data data for callouts (see 49 below)
2895     The flag bits are also defined in pcre.h, and are
2901     The pcre_study() function now returns one of these new pcre_extra blocks, with
2902     the actual study data pointed to by the study_data field, and the
2903     PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
2904     before. That is, this change is entirely upwards-compatible and requires no
2905     change to existing code.
2907     If you want to pass in additional data to pcre_exec(), you can either place it
2908     in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
2909     block.
2911     46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
2912     data string contains the escape sequence \M, pcretest calls pcre_exec() several
2913     times with different match limits, until it finds the minimum value needed for
2914     pcre_exec() to complete. The value is then output. This can be instructive; for
2915     most simple matches the number is quite small, but for pathological cases it
2916     gets very large very quickly.
2918     47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
2919     returns the size of the data block pointed to by the study_data field in a
2920     pcre_extra block, that is, the value that was passed as the argument to
2921     pcre_malloc() when PCRE was getting memory in which to place the information
2922     created by pcre_study(). The fourth argument should point to a size_t variable.
2923     pcretest has been extended so that this information is shown after a successful
2924     pcre_study() call when information about the compiled regex is being displayed.
2926     48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
2927     because what follows is always an absolute path. (Later: it turns out that this
2928     is more than cosmetic for MinGW, because it doesn't like empty path
2929     components.)
2931     49. Some changes have been made to the callout feature (see 28 above):
2933     (i) A callout function now has three choices for what it returns:
2935     0 => success, carry on matching
2936     > 0 => failure at this point, but backtrack if possible
2937     < 0 => serious error, return this value from pcre_exec()
2939     Negative values should normally be chosen from the set of PCRE_ERROR_xxx
2940     values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
2941     "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
2942     use by callout functions. It will never be used by PCRE itself.
2944     (ii) The pcre_extra structure (see 45 above) has a void * field called
2945     callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
2946     pcre_callout_block structure has a field of the same name. The contents of
2947     the field passed in the pcre_extra structure are passed to the callout
2948     function in the corresponding field in the callout block. This makes it
2949     easier to use the same callout-containing regex from multiple threads. For
2950     testing, the pcretest program has a new data escape
2952     \C*n pass the number n (may be negative) as callout_data
2954     If the callout function in pcretest receives a non-zero value as
2955     callout_data, it returns that value.
2957     50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
2958     there were some redundant $(CFLAGS) in commands that are now specified as
2959     $(LINK), which already includes $(CFLAGS).
2961     51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
2962     has been compiled with UTF-8 support *and* pcre_compile() has been compiled
2963     with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
2964     one-byte characters throughout. Note that case-insensitive matching applies
2965     only to characters whose values are less than 256. PCRE doesn't support the
2966     notion of cases for higher-valued characters.
2968     (i) A character class whose characters are all within 0-255 is handled as
2969     a bit map, and the map is inverted for negative classes. Previously, a
2970     character > 255 always failed to match such a class; however it should
2971     match if the class was a negative one (e.g. [^ab]). This has been fixed.
2973     (ii) A negated character class with a single character < 255 is coded as
2974     "not this character" (OP_NOT). This wasn't working properly when the test
2975     character was multibyte, either singly or repeated.
2977     (iii) Repeats of multibyte characters are now handled correctly in UTF-8
2978     mode, for example: \x{100}{2,3}.
2980     (iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
2981     singly or repeated) now correctly test multibyte characters. However,
2982     PCRE doesn't recognize any characters with values greater than 255 as
2983     digits, spaces, or word characters. Such characters always match \D, \S,
2984     and \W, and never match \d, \s, or \w.
2986     (v) Classes may now contain characters and character ranges with values
2987     greater than 255. For example: [ab\x{100}-\x{400}].
2989     (vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
2990     PCRE in UTF-8 mode.
2992     52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
2993     PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
2994     retained for backwards compatibility. (Note that LASTLITERAL is also a byte
2995     value.)
2997     53. The single man page has become too large. I have therefore split it up into
2998     a number of separate man pages. These also give rise to individual HTML pages;
2999     these are now put in a separate directory, and there is an index.html page that
3000     lists them all. Some hyperlinking between the pages has been installed.
3002     54. Added convenience functions for handling named capturing parentheses.
3004     55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
3005     aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
3006     true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
3007     are faulted.
3009     56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
3010     calling configure. These values are used when compiling the dftables.c program
3011     which is run to generate the source of the default character tables. They
3012     default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
3013     you will need to set these values.
3015     57. Updated the building process for Windows DLL, as provided by Fred Cox.
3018     Version 3.9 02-Jan-02
3019 nigel 61 ---------------------
3021     1. A bit of extraneous text had somehow crept into the pcregrep documentation.
3023     2. If --disable-static was given, the building process failed when trying to
3024     build pcretest and pcregrep. (For some reason it was using libtool to compile
3025     them, which is not right, as they aren't part of the library.)
3028 nigel 59 Version 3.8 18-Dec-01
3029     ---------------------
3031     1. The experimental UTF-8 code was completely screwed up. It was packing the
3032     bytes in the wrong order. How dumb can you get?
3035 nigel 57 Version 3.7 29-Oct-01
3036     ---------------------
3038     1. In updating pcretest to check change 1 of version 3.6, I screwed up.
3039     This caused pcretest, when used on the test data, to segfault. Unfortunately,
3040     this didn't happen under Solaris 8, where I normally test things.
3042 nigel 59 2. The Makefile had to be changed to make it work on BSD systems, where 'make'
3043     doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
3044     isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
3045     this fix an hour or so after the initial 3.7 release.)
3046 nigel 57
3047 nigel 59
3048 nigel 55 Version 3.6 23-Oct-01
3049     ---------------------
3051     1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
3052     offsets passed as NULL with zero offset count.
3054     2. The config.guess and config.sub files had not been updated when I moved to
3055     the latest autoconf.
3058 nigel 53 Version 3.5 15-Aug-01
3059     ---------------------
3060 nigel 5
3061 nigel 53 1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
3062     had been forgotten.
3064     2. By using declared but undefined structures, we can avoid using "void"
3065     definitions in pcre.h while keeping the internal definitions of the structures
3066     private.
3068     3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
3069     user point of view, this means that both static and shared libraries are built
3070     by default, but this can be individually controlled. More of the work of
3071     handling this static/shared cases is now inside libtool instead of PCRE's make
3072     file.
3074     4. The pcretest utility is now installed along with pcregrep because it is
3075     useful for users (to test regexs) and by doing this, it automatically gets
3076     relinked by libtool. The documentation has been turned into a man page, so
3077     there are now .1, .txt, and .html versions in /doc.
3079     5. Upgrades to pcregrep:
3080     (i) Added long-form option names like gnu grep.
3081     (ii) Added --help to list all options with an explanatory phrase.
3082     (iii) Added -r, --recursive to recurse into sub-directories.
3083     (iv) Added -f, --file to read patterns from a file.
3085     6. pcre_exec() was referring to its "code" argument before testing that
3086     argument for NULL (and giving an error if it was NULL).
3088     7. Upgraded Makefile.in to allow for compiling in a different directory from
3089     the source directory.
3091     8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
3092     options bits, the pointer it was passed was to an int instead of to an unsigned
3093     long int. This mattered only on 64-bit systems.
3095     9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
3096     generated) instead of pcre.in, which it its source. Also made the same change
3097     in several of the .c files.
3099     10. A new release of gcc defines printf() as a macro, which broke pcretest
3100     because it had an ifdef in the middle of a string argument for printf(). Fixed
3101     by using separate calls to printf().
3103     11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
3104     script, to force use of CR or LF instead of \n in the source. On non-Unix
3105     systems, the value can be set in config.h.
3107     12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
3108     absolute limit. Changed the text of the error message to make this clear, and
3109     likewise updated the man page.
3111     13. The limit of 99 on the number of capturing subpatterns has been removed.
3112     The new limit is 65535, which I hope will not be a "real" limit.
3115 nigel 51 Version 3.4 22-Aug-00
3116     ---------------------
3118     1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
3120     2. Diagnose condition (?(0) as an error instead of crashing on matching.
3123 nigel 49 Version 3.3 01-Aug-00
3124     ---------------------
3126     1. If an octal character was given, but the value was greater than \377, it
3127     was not getting masked to the least significant bits, as documented. This could
3128     lead to crashes in some systems.
3130     2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
3131     the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
3133     3. Added the functions pcre_free_substring() and pcre_free_substring_list().
3134     These just pass their arguments on to (pcre_free)(), but they are provided
3135     because some uses of PCRE bind it to non-C systems that can call its functions,
3136     but cannot call free() or pcre_free() directly.
3138     4. Add "make test" as a synonym for "make check". Corrected some comments in
3139     the Makefile.
3141     5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
3142     Makefile.
3144     6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
3145     command called pgrep for grepping around the active processes.
3147     7. Added the beginnings of support for UTF-8 character strings.
3149     8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
3150     RANLIB to ./ltconfig so that they are used by libtool. I think these are all
3151     the relevant ones. (AR is not passed because ./ltconfig does its own figuring
3152     out for the ar command.)
3155 nigel 47 Version 3.2 12-May-00
3156     ---------------------
3158     This is purely a bug fixing release.
3160     1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
3161     of ZA. This was just one example of several cases that could provoke this bug,
3162     which was introduced by change 9 of version 2.00. The code for breaking
3163     infinite loops after an iteration that matches an empty string was't working
3164     correctly.
3166     2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
3167     when matched against abbab (for example). After matching an empty string, it
3168     wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
3169     caused it to match further down the string than it should.
3171     3. The code contained an inclusion of sys/types.h. It isn't clear why this
3172     was there because it doesn't seem to be needed, and it causes trouble on some
3173     systems, as it is not a Standard C header. It has been removed.
3175     4. Made 4 silly changes to the source to avoid stupid compiler warnings that
3176     were reported on the Macintosh. The changes were from
3178     while ((c = *(++ptr)) != 0 && c != '\n');
3179     to
3180     while ((c = *(++ptr)) != 0 && c != '\n') ;
3182     Totally extraordinary, but if that's what it takes...
3184     5. PCRE is being used in one environment where neither memmove() nor bcopy() is
3185     available. Added HAVE_BCOPY and an autoconf test for it; if neither
3186     HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
3187     assumes the way PCRE uses memmove() (always moving upwards).
3189     6. PCRE is being used in one environment where strchr() is not available. There
3190     was only one use in pcre.c, and writing it out to avoid strchr() probably gives
3191     faster code anyway.
3194 nigel 45 Version 3.1 09-Feb-00
3195     ---------------------
3197     The only change in this release is the fixing of some bugs in Makefile.in for
3198     the "install" target:
3200     (1) It was failing to install pcreposix.h.
3202     (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
3205 nigel 43 Version 3.0 01-Feb-00
3206     ---------------------
3207 nigel 41
3208     1. Add support for the /+ modifier to perltest (to output $` like it does in
3209     pcretest).
3211     2. Add support for the /g modifier to perltest.
3213     3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
3214     matches null strings.
3216     4. Fix perltest so that it doesn't do unwanted things when fed an empty
3217     pattern. Perl treats empty patterns specially - it reuses the most recent
3218     pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
3219     effect.
3221     5. The POSIX interface was broken in that it was just handing over the POSIX
3222     captured string vector to pcre_exec(), but (since release 2.00) PCRE has
3223     required a bigger vector, with some working space on the end. This means that
3224     the POSIX wrapper now has to get and free some memory, and copy the results.
3226 nigel 43 6. Added some simple autoconf support, placing the test data and the
3227     documentation in separate directories, re-organizing some of the
3228     information files, and making it build pcre-config (a GNU standard). Also added
3229     libtool support for building PCRE as a shared library, which is now the
3230     default.
3231 nigel 41
3232 nigel 43 7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
3233     09 are not valid octal constants. Single digits will be used for minor values
3234     less than 10.
3236     8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
3237     existing programs that set these in the POSIX interface can use PCRE without
3238     modification.
3240     9. Added a new function, pcre_fullinfo() with an extensible interface. It can
3241     return all that pcre_info() returns, plus additional data. The pcre_info()
3242     function is retained for compatibility, but is considered to be obsolete.
3244     10. Added experimental recursion feature (?R) to handle one common case that
3245     Perl 5.6 will be able to do with (?p{...}).
3247     11. Added support for POSIX character classes like [:alpha:], which Perl is
3248     adopting.
3251 nigel 39 Version 2.08 31-Aug-99
3252     ----------------------
3254     1. When startoffset was not zero and the pattern began with ".*", PCRE was not
3255     trying to match at the startoffset position, but instead was moving forward to
3256     the next newline as if a previous match had failed.
3258     2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
3259     and could get into a loop if a null string was matched other than at the start
3260     of the subject.
3262     3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
3263     be distinguished at compile time, and for completeness also added PCRE_DATE.
3265     5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
3266     in GnuWin32 environments.
3269 nigel 37 Version 2.07 29-Jul-99
3270     ----------------------
3272     1. The documentation is now supplied in plain text form and HTML as well as in
3273     the form of man page sources.
3275     2. C++ compilers don't like assigning (void *) values to other pointer types.
3276     In particular this affects malloc(). Although there is no problem in Standard
3277     C, I've put in casts to keep C++ compilers happy.
3279     3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
3280     should be (const char *).
3282     4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
3283     be useful for non-Unix systems who don't want to bother with the POSIX stuff.
3284     However, I haven't made this a standard facility. The documentation doesn't
3285     mention it, and the Makefile doesn't support it.
3287     5. The Makefile now contains an "install" target, with editable destinations at
3288     the top of the file. The pcretest program is not installed.
3290     6. pgrep -V now gives the PCRE version number and date.
3292     7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
3293     causing the entire string to be ignored, instead of just the last character.
3295     8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
3296     non-matching string, it can take a very, very long time, even for strings of
3297     quite modest length, because of the nested recursion. PCRE now does better in
3298     some of these cases. It does this by remembering the last required literal
3299     character in the pattern, and pre-searching the subject to ensure it is present
3300     before running the real match. In other words, it applies a heuristic to detect
3301     some types of certain failure quickly, and in the above example, if presented
3302     with a string that has no trailing " it gives "no match" very quickly.
3304     9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
3305     other alternatives are tried instead.
3308 nigel 35 Version 2.06 09-Jun-99
3309     ----------------------
3311     1. Change pcretest's output for amount of store used to show just the code
3312     space, because the remainder (the data block) varies in size between 32-bit and
3313     64-bit systems.
3315     2. Added an extra argument to pcre_exec() to supply an offset in the subject to
3316     start matching at. This allows lookbehinds to work when searching for multiple
3317     occurrences in a string.
3319     3. Added additional options to pcretest for testing multiple occurrences:
3321     /+ outputs the rest of the string that follows a match
3322     /g loops for multiple occurrences, using the new startoffset argument
3323     /G loops for multiple occurrences by passing an incremented pointer
3325     4. PCRE wasn't doing the "first character" optimization for patterns starting
3326     with \b or \B, though it was doing it for other lookbehind assertions. That is,
3327     it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
3328     the letter 'x'. On long subject strings, this gives a significant speed-up.
3331 nigel 33 Version 2.05 21-Apr-99
3332     ----------------------
3334     1. Changed the type of magic_number from int to long int so that it works
3335     properly on 16-bit systems.
3337     2. Fixed a bug which caused patterns starting with .* not to work correctly
3338     when the subject string contained newline characters. PCRE was assuming
3339     anchoring for such patterns in all cases, which is not correct because .* will
3340     not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
3341     DOTALL is set at top level; otherwise it knows that patterns starting with .*
3342     must be retried after every newline in the subject.
3345 nigel 31 Version 2.04 18-Feb-99
3346     ----------------------
3348     1. For parenthesized subpatterns with repeats whose minimum was zero, the
3349     computation of the store needed to hold the pattern was incorrect (too large).
3350     If such patterns were nested a few deep, this could multiply and become a real
3351     problem.
3353     2. Added /M option to pcretest to show the memory requirement of a specific
3354     pattern. Made -m a synonym of -s (which does this globally) for compatibility.
3356     3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
3357     compiled in such a way that the backtracking after subsequent failure was
3358     pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
3359     ((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
3362 nigel 29 Version 2.03 02-Feb-99
3363     ----------------------
3365     1. Fixed typo and small mistake in man page.
3367 nigel 31 2. Added 4th condition (GPL supersedes if conflict) and created separate
3368     LICENCE file containing the conditions.
3369 nigel 29
3370     3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
3371     Perl, that is the internal \ allows the delimiter to be included in the
3372     pattern. Locked out the use of \ as a delimiter. If \ immediately follows
3373     the final delimiter, add \ to the end of the pattern (to test the error).
3375     4. Added the convenience functions for extracting substrings after a successful
3376     match. Updated pcretest to make it able to test these functions.
3379 nigel 27 Version 2.02 14-Jan-99
3380     ----------------------
3382     1. Initialized the working variables associated with each extraction so that
3383     their saving and restoring doesn't refer to uninitialized store.
3385     2. Put dummy code into study.c in order to trick the optimizer of the IBM C
3386     compiler for OS/2 into generating correct code. Apparently IBM isn't going to
3387     fix the problem.
3389     3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
3390     calls, and wasn't printing the correct value for compiling calls. Increased the
3391     default value of LOOPREPEAT, and the number of significant figures in the
3392     times.
3394     4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
3396     5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
3397     a building problem on Windows NT with a FAT file system.
3400 nigel 25 Version 2.01 21-Oct-98
3401     ----------------------
3403     1. Changed the API for pcre_compile() to allow for the provision of a pointer
3404     to character tables built by pcre_maketables() in the current locale. If NULL
3405     is passed, the default tables are used.
3408 nigel 23 Version 2.00 24-Sep-98
3409 nigel 21 ----------------------
3411 nigel 23 1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
3412     it any more.
3414     2. Allow quantification of (?>) groups, and make it work correctly.
3416     3. The first character computation wasn't working for (?>) groups.
3418     4. Correct the implementation of \Z (it is permitted to match on the \n at the
3419     end of the subject) and add 5.005's \z, which really does match only at the
3420     very end of the subject.
3422     5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
3424     6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
3425     DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
3426     localized options. All options to pcre_study() were also removed.
3428     7. Add other new features from 5.005:
3430     $(?<= positive lookbehind
3431     $(?<! negative lookbehind
3432     (?imsx-imsx) added the unsetting capability
3433     such a setting is global if at outer level; local otherwise
3434     (?imsx-imsx:) non-capturing groups with option setting
3435     (?(cond)re|re) conditional pattern matching
3437     A backreference to itself in a repeated group matches the previous
3438     captured string.
3440     8. General tidying up of studying (both automatic and via "study")
3441     consequential on the addition of new assertions.
3443     9. As in 5.005, unlimited repeated groups that could match an empty substring
3444     are no longer faulted at compile time. Instead, the loop is forcibly broken at
3445     runtime if any iteration does actually match an empty substring.
3447     10. Include the RunTest script in the distribution.
3449     11. Added tests from the Perl 5.005_02 distribution. This showed up a few
3450     discrepancies, some of which were old and were also with respect to 5.004. They
3451     have now been fixed.
3454     Version 1.09 28-Apr-98
3455     ----------------------
3457 nigel 21 1. A negated single character class followed by a quantifier with a minimum
3458     value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
3459     program crashes, or just wrong answers. This did not apply to negated classes
3460     containing more than one character, or to minima other than one.
3463 nigel 19 Version 1.08 27-Mar-98
3464     ----------------------
3466     1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
3468     2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
3469     latter must appear before anything that relies on it in the pattern.
3472 nigel 17 Version 1.07 16-Feb-98
3473     ----------------------
3475     1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
3476     repeat of a potentially empty string).
3479 nigel 15 Version 1.06 23-Jan-98
3480     ----------------------
3482     1. Added Markus Oberhumer's little patches for C++.
3484     2. Literal strings longer than 255 characters were broken.
3487 nigel 13 Version 1.05 23-Dec-97
3488     ----------------------
3490     1. Negated character classes containing more than one character were failing if
3491     PCRE_CASELESS was set at run time.
3494 nigel 11 Version 1.04 19-Dec-97
3495     ----------------------
3497     1. Corrected the man page, where some "const" qualifiers had been omitted.
3499     2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
3500     input syntax.
3502     3. Fixed memory leak which occurred when a regex with back references was
3503     matched with an offsets vector that wasn't big enough. The temporary memory
3504     that is used in this case wasn't being freed if the match failed.
3506     4. Tidied pcretest to ensure it frees memory that it gets.
3508     5. Temporary memory was being obtained in the case where the passed offsets
3509     vector was exactly big enough.
3511     6. Corrected definition of offsetof() from change 5 below.
3513     7. I had screwed up change 6 below and broken the rules for the use of
3514     setjmp(). Now fixed.
3517 nigel 9 Version 1.03 18-Dec-97
3518     ----------------------
3520     1. A erroneous regex with a missing opening parenthesis was correctly
3521     diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
3522     on some systems.
3524     2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
3525     it was reported that one broken compiler failed on the former because "code" is
3526     also an independent variable.
3528     3. The erroneous regex a[]b caused an array overrun reference.
3530     4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
3531     fail on data ending with that character. (It was going on too far, and checking
3532     the next character, typically a binary zero.) This was specific to the
3533     optimized code for single-character negative classes.
3535     5. Added a contributed patch from the TIN world which does the following:
3537     + Add an undef for memmove, in case the the system defines a macro for it.
3539     + Add a definition of offsetof(), in case there isn't one. (I don't know
3540     the reason behind this - offsetof() is part of the ANSI standard - but
3541     it does no harm).
3543     + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
3544     most of the places where whitespace preceded '#'. I have given up and
3545     allowed the remaining 2 cases to be at the margin.
3547     + Rename some variables in pcre to eliminate shadowing. This seems very
3548     pedantic, but does no harm, of course.
3550     6. Moved the call to setjmp() into its own function, to get rid of warnings
3551     from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
3553     7. Constructs such as \d{8,} were compiling into the equivalent of
3554 nigel 11 \d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
3555 nigel 9 outcome, but in this particular case used more store than had been allocated,
3556     which caused the bug to be discovered because it threw up an internal error.
3558     8. The debugging code in both pcre and pcretest for outputting the compiled
3559     form of a regex was going wrong in the case of back references followed by
3560     curly-bracketed repeats.
3563 nigel 7 Version 1.02 12-Dec-97
3564     ----------------------
3566     1. Typos in pcre.3 and comments in the source fixed.
3568     2. Applied a contributed patch to get rid of places where it used to remove
3569     'const' from variables, and fixed some signed/unsigned and uninitialized
3570     variable warnings.
3572     3. Added the "runtest" target to Makefile.
3574     4. Set default compiler flag to -O2 rather than just -O.
3577 nigel 5 Version 1.01 19-Nov-97
3578     ----------------------
3580     1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
3581     like /([ab]*)*/, that is, for classes with more than one character in them.
3583     2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
3584     as /((?>a*))*/ (a PCRE_EXTRA facility).
3587     Version 1.00 18-Nov-97
3588     ----------------------
3590     1. Added compile-time macros to support systems such as SunOS4 which don't have
3591     memmove() or strerror() but have other things that can be used instead.
3593     2. Arranged that "make clean" removes the executables.
3596 nigel 3 Version 0.99 27-Oct-97
3597     ----------------------
3599     1. Fixed bug in code for optimizing classes with only one character. It was
3600     initializing a 32-byte map regardless, which could cause it to run off the end
3601     of the memory it had got.
3603     2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
3606     Version 0.98 22-Oct-97
3607     ----------------------
3609     1. Fixed bug in code for handling temporary memory usage when there are more
3610     back references than supplied space in the ovector. This could cause segfaults.
3613     Version 0.97 21-Oct-97
3614     ----------------------
3616     1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
3618     2. Optimized negated single characters not to use a bit map.
3620     3. Brought error texts together as macro definitions; clarified some of them;
3621     fixed one that was wrong - it said "range out of order" when it meant "invalid
3622     escape sequence".
3624     4. Changed some char * arguments to const char *.
3626     5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
3628     6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
3629     pcretest.
3632     Version 0.96 16-Oct-97
3633     ----------------------
3635     1. Added a simple "pgrep" utility to the distribution.
3637     2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
3638     unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
3639     where "ddd" means "one or more decimal digits".
3641     3. Fixed serious bug. If a pattern had a back reference, but the call to
3642     pcre_exec() didn't supply a large enough ovector to record the related
3643     identifying subpattern, the match always failed. PCRE now remembers the number
3644     of the largest back reference, and gets some temporary memory in which to save
3645     the offsets during matching if necessary, in order to ensure that
3646     backreferences always work.
3648     4. Increased the compatibility with Perl in a number of ways:
3650     (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
3651     to request this handling. The option can be set at compile or exec time.
3653     (b) $ matches before a terminating newline by default; an option
3654     PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
3655     mode). The option can be set at compile or exec time.
3657     (c) The handling of \ followed by a digit other than 0 is now supposed to be
3658     the same as Perl's. If the decimal number it represents is less than 10
3659     or there aren't that many previous left capturing parentheses, an octal
3660     escape is read. Inside a character class, it's always an octal escape,
3661     even if it is a single digit.
3663     (d) An escaped but undefined alphabetic character is taken as a literal,
3664     unless PCRE_EXTRA is set. Currently this just reserves the remaining
3665     escapes.
3667     (e) {0} is now permitted. (The previous item is removed from the compiled
3668     pattern).
3670     5. Changed all the names of code files so that the basic parts are no longer
3671     than 10 characters, and abolished the teeny "globals.c" file.
3673     6. Changed the handling of character classes; they are now done with a 32-byte
3674     bit map always.
3676     7. Added the -d and /D options to pcretest to make it possible to look at the
3677     internals of compilation without having to recompile pcre.
3680     Version 0.95 23-Sep-97
3681     ----------------------
3683     1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
3684     \x20 at the start of a run of normal characters. These were being treated as
3685     real characters, instead of the source characters being re-checked.
3688     Version 0.94 18-Sep-97
3689     ----------------------
3691     1. The functions are now thread-safe, with the caveat that the global variables
3692     containing pointers to malloc() and free() or alternative functions are the
3693     same for all threads.
3695     2. Get pcre_study() to generate a bitmap of initial characters for non-
3696     anchored patterns when this is possible, and use it if passed to pcre_exec().
3699     Version 0.93 15-Sep-97
3700     ----------------------
3702     1. /(b)|(:+)/ was computing an incorrect first character.
3704     2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
3705     but not actually doing anything yet.
3707     3. Treat "-" characters in classes that cannot be part of ranges as literals,
3708     as Perl does (e.g. [-az] or [az-]).
3710     4. Set the anchored flag if a branch starts with .* or .*? because that tests
3711     all possible positions.
3713     5. Split up into different modules to avoid including unneeded functions in a
3714     compiled binary. However, compile and exec are still in one module. The "study"
3715     function is split off.
3717     6. The character tables are now in a separate module whose source is generated
3718     by an auxiliary program - but can then be edited by hand if required. There are
3719     now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
3720     toupper() in the code.
3722     7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
3723     make them global. Abolish the function for setting them, as the caller can now
3724     set them directly.
3727     Version 0.92 11-Sep-97
3728     ----------------------
3730     1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
3731     (e.g. /a{1,3}/) was broken (I mis-optimized it).
3733     2. Caseless matching was not working in character classes if the characters in
3734     the pattern were in upper case.
3736     3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
3738     4. Make PCRE_ANCHORED public and accept as a compile option.
3740     5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
3741     PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
3742     pass them.
3744     6. Give an error if bad option bits passed at compile or run time.
3746     7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
3747     pcretest to cause it to pass that flag.
3749     8. Add pcre_info(), to get the number of identifying subpatterns, the stored
3750     options, and the first character, if set.
3752     9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
3755     Version 0.91 10-Sep-97
3756     ----------------------
3758     1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
3759     match the empty string as in /(a*)*/. It was looping and ultimately crashing.
3761     2. PCRE was looping on encountering an indefinitely repeated back reference to
3762     a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
3763     Perl does - treats the match as successful.
3765     ****


Name Value
svn:eol-style native
svn:keywords "Author Date Id Revision Url"

ViewVC Help
Powered by ViewVC 1.1.12