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Revision 616 - (show annotations)
Mon Jul 11 15:55:25 2011 UTC (10 years, 2 months ago) by ph10
File size: 205294 byte(s)
Add the ++ feature to pcretest.
1 ChangeLog for PCRE
2 ------------------
4 Version 8.13 30-Apr-2011
5 ------------------------
7 1. The Unicode data tables have been updated to Unicode 6.0.0.
9 2. Two minor typos in pcre_internal.h have been fixed.
11 3. Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
12 pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
13 in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
15 4. There were a number of related bugs in the code for matching backrefences
16 caselessly in UTF-8 mode when codes for the characters concerned were
17 different numbers of bytes. For example, U+023A and U+2C65 are an upper
18 and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
19 (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
20 code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
21 2-byte code at the end of the subject (it thought there wasn't enough data
22 left).
24 5. Comprehensive information about what went wrong is now returned by
25 pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
26 as the output vector has at least 2 elements. The offset of the start of
27 the failing character and a reason code are placed in the vector.
29 6. When the UTF-8 string check fails for pcre_compile(), the offset that is
30 now returned is for the first byte of the failing character, instead of the
31 last byte inspected. This is an incompatible change, but I hope it is small
32 enough not to be a problem. It makes the returned offset consistent with
33 pcre_exec() and pcre_dfa_exec().
35 7. pcretest now gives a text phrase as well as the error number when
36 pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
37 failure, the offset and reason code are output.
39 8. When \R was used with a maximizing quantifier it failed to skip backwards
40 over a \r\n pair if the subsequent match failed. Instead, it just skipped
41 back over a single character (\n). This seems wrong (because it treated the
42 two characters as a single entity when going forwards), conflicts with the
43 documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
44 behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
45 has been changed.
47 9. Some internal refactoring has changed the processing so that the handling
48 of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
49 time (the PCRE_DOTALL option was changed this way some time ago: version
50 7.7 change 16). This has made it possible to abolish the OP_OPT op code,
51 which was always a bit of a fudge. It also means that there is one less
52 argument for the match() function, which reduces its stack requirements
53 slightly. This change also fixes an incompatibility with Perl: the pattern
54 (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
56 10. More internal refactoring has drastically reduced the number of recursive
57 calls to match() for possessively repeated groups such as (abc)++ when
58 using pcre_exec().
60 11. While implementing 10, a number of bugs in the handling of groups were
61 discovered and fixed:
63 (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
64 (a|)*(?1) gave a compile-time internal error.
65 ((a|)+)+ did not notice that the outer group could match an empty string.
66 (^a|^)+ was not marked as anchored.
67 (.*a|.*)+ was not marked as matching at start or after a newline.
69 12. Yet more internal refactoring has removed another argument from the match()
70 function. Special calls to this function are now indicated by setting a
71 value in a variable in the "match data" data block.
73 13. Be more explicit in pcre_study() instead of relying on "default" for
74 opcodes that mean there is no starting character; this means that when new
75 ones are added and accidentally left out of pcre_study(), testing should
76 pick them up.
78 14. The -s option of pcretest has been documented for ages as being an old
79 synonym of -m (show memory usage). I have changed it to mean "force study
80 for every regex", that is, assume /S for every regex. This is similar to -i
81 and -d etc. It's slightly incompatible, but I'm hoping nobody is still
82 using it. It makes it easier to run collections of tests with and without
83 study enabled, and thereby test pcre_study() more easily. All the standard
84 tests are now run with and without -s (but some patterns can be marked as
85 "never study" - see 20 below).
87 15. When (*ACCEPT) was used in a subpattern that was called recursively, the
88 restoration of the capturing data to the outer values was not happening
89 correctly.
91 16. If a recursively called subpattern ended with (*ACCEPT) and matched an
92 empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
93 pattern had matched an empty string, and so incorrectly returned a no
94 match.
96 17. There was optimizing code for the last branch of non-capturing parentheses,
97 and also for the obeyed branch of a conditional subexpression, which used
98 tail recursion to cut down on stack usage. Unfortunately, not that there is
99 the possibility of (*THEN) occurring in these branches, tail recursion is
100 no longer possible because the return has to be checked for (*THEN). These
101 two optimizations have therefore been removed.
103 18. If a pattern containing \R was studied, it was assumed that \R always
104 matched two bytes, thus causing the minimum subject length to be
105 incorrectly computed because \R can also match just one byte.
107 19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
108 was incorrectly computed.
110 20. If /S is present twice on a test pattern in pcretest input, it *disables*
111 studying, thereby overriding the use of -s on the command line. This is
112 necessary for one or two tests to keep the output identical in both cases.
114 21. When (*ACCEPT) was used in an assertion that matched an empty string and
115 PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
117 22. When an atomic group that contained a capturing parenthesis was
118 successfully matched, but the branch in which it appeared failed, the
119 capturing was not being forgotten if a higher numbered group was later
120 captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
121 group 1 to "a", when in fact it should be unset. This applied to multi-
122 branched capturing and non-capturing groups, repeated or not, and also to
123 positive assertions (capturing in negative assertions is not well defined
124 in PCRE) and also to nested atomic groups.
126 23. Add the ++ qualifier feature to pcretest, to show the remainder of the
127 subject after a captured substring (to make it easier to tell which of a
128 number of identical substrings has been captured).
131 Version 8.12 15-Jan-2011
132 ------------------------
134 1. Fixed some typos in the markup of the man pages, and wrote a script that
135 checks for such things as part of the documentation building process.
137 2. On a big-endian 64-bit system, pcregrep did not correctly process the
138 --match-limit and --recursion-limit options (added for 8.11). In
139 particular, this made one of the standard tests fail. (The integer value
140 went into the wrong half of a long int.)
142 3. If the --colour option was given to pcregrep with -v (invert match), it
143 did strange things, either producing crazy output, or crashing. It should,
144 of course, ignore a request for colour when reporting lines that do not
145 match.
147 4. Another pcregrep bug caused similar problems if --colour was specified with
148 -M (multiline) and the pattern match finished with a line ending.
150 5. In pcregrep, when a pattern that ended with a literal newline sequence was
151 matched in multiline mode, the following line was shown as part of the
152 match. This seems wrong, so I have changed it.
154 6. Another pcregrep bug in multiline mode, when --colour was specified, caused
155 the check for further matches in the same line (so they could be coloured)
156 to overrun the end of the current line. If another match was found, it was
157 incorrectly shown (and then shown again when found in the next line).
159 7. If pcregrep was compiled under Windows, there was a reference to the
160 function pcregrep_exit() before it was defined. I am assuming this was
161 the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
162 reported by a user. I've moved the definition above the reference.
165 Version 8.11 10-Dec-2010
166 ------------------------
168 1. (*THEN) was not working properly if there were untried alternatives prior
169 to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
170 backtracked to try for "b" instead of moving to the next alternative branch
171 at the same level (in this case, to look for "c"). The Perl documentation
172 is clear that when (*THEN) is backtracked onto, it goes to the "next
173 alternative in the innermost enclosing group".
175 2. (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
176 such as (A(*COMMIT)B(*THEN)C|D) any failure after matching A should
177 result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
178 (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
179 (*THEN).
181 3. If \s appeared in a character class, it removed the VT character from
182 the class, even if it had been included by some previous item, for example
183 in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
184 of \s, but is part of the POSIX "space" class.)
186 4. A partial match never returns an empty string (because you can always
187 match an empty string at the end of the subject); however the checking for
188 an empty string was starting at the "start of match" point. This has been
189 changed to the "earliest inspected character" point, because the returned
190 data for a partial match starts at this character. This means that, for
191 example, /(?<=abc)def/ gives a partial match for the subject "abc"
192 (previously it gave "no match").
194 5. Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
195 of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
196 previously a full match would be given. However, setting PCRE_PARTIAL_HARD
197 has an implication that the given string is incomplete (because a partial
198 match is preferred over a full match). For this reason, these items now
199 give a partial match in this situation. [Aside: previously, the one case
200 /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
201 match rather than a full match, which was wrong by the old rules, but is
202 now correct.]
204 6. There was a bug in the handling of #-introduced comments, recognized when
205 PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
206 If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
207 UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
208 scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
209 but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
210 places in pcre_compile().
212 7. Related to (6) above, when pcre_compile() was skipping #-introduced
213 comments when looking ahead for named forward references to subpatterns,
214 the only newline sequence it recognized was NL. It now handles newlines
215 according to the set newline convention.
217 8. SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
218 former, but used strtoul(), whereas pcretest avoided strtoul() but did not
219 cater for a lack of strerror(). These oversights have been fixed.
221 9. Added --match-limit and --recursion-limit to pcregrep.
223 10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
225 11. When the -o option was used, pcregrep was setting a return code of 1, even
226 when matches were found, and --line-buffered was not being honoured.
228 12. Added an optional parentheses number to the -o and --only-matching options
229 of pcregrep.
231 13. Imitating Perl's /g action for multiple matches is tricky when the pattern
232 can match an empty string. The code to do it in pcretest and pcredemo
233 needed fixing:
235 (a) When the newline convention was "crlf", pcretest got it wrong, skipping
236 only one byte after an empty string match just before CRLF (this case
237 just got forgotten; "any" and "anycrlf" were OK).
239 (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
240 mode when an empty string match preceded an ASCII character followed by
241 a non-ASCII character. (The code for advancing by one character rather
242 than one byte was nonsense.)
244 (c) The pcredemo.c sample program did not have any code at all to handle
245 the cases when CRLF is a valid newline sequence.
247 14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
248 as a starting offset was within the subject string. There is now a new
249 error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
250 negative or greater than the length of the string. In order to test this,
251 pcretest is extended to allow the setting of negative starting offsets.
253 15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
254 starting offset points to the beginning of a UTF-8 character was
255 unnecessarily clumsy. I tidied it up.
257 16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
258 bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
260 17. Nobody had reported that the --include_dir option, which was added in
261 release 7.7 should have been called --include-dir (hyphen, not underscore)
262 for compatibility with GNU grep. I have changed it to --include-dir, but
263 left --include_dir as an undocumented synonym, and the same for
264 --exclude-dir, though that is not available in GNU grep, at least as of
265 release 2.5.4.
267 18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
268 characters from a string of bytes) have been redefined so as not to use
269 loops, in order to improve performance in some environments. At the same
270 time, I abstracted some of the common code into auxiliary macros to save
271 repetition (this should not affect the compiled code).
273 19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
274 compile-time error is now given if \c is not followed by an ASCII
275 character, that is, a byte less than 128. (In EBCDIC mode, the code is
276 different, and any byte value is allowed.)
278 20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
279 START_OPTIMIZE option, which is now allowed at compile time - but just
280 passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
281 to pcregrep and other applications that have no direct access to PCRE
282 options. The new /Y option in pcretest sets this option when calling
283 pcre_compile().
285 21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
286 back references. Groups containing recursive back references were forced to
287 be atomic by that change, but in the case of named groups, the amount of
288 memory required was incorrectly computed, leading to "Failed: internal
289 error: code overflow". This has been fixed.
291 22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
292 pcretest.c, to avoid build problems in some Borland environments.
295 Version 8.10 25-Jun-2010
296 ------------------------
298 1. Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
299 THEN.
301 2. (*ACCEPT) was not working when inside an atomic group.
303 3. Inside a character class, \B is treated as a literal by default, but
304 faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
305 causes the error). The code is unchanged, but I tidied the documentation.
307 4. Inside a character class, PCRE always treated \R and \X as literals,
308 whereas Perl faults them if its -w option is set. I have changed PCRE so
309 that it faults them when PCRE_EXTRA is set.
311 5. Added support for \N, which always matches any character other than
312 newline. (It is the same as "." when PCRE_DOTALL is not set.)
314 6. When compiling pcregrep with newer versions of gcc which may have
315 FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
316 declared with attribute warn_unused_result" were given. Just casting the
317 result to (void) does not stop the warnings; a more elaborate fudge is
318 needed. I've used a macro to implement this.
320 7. Minor change to pcretest.c to avoid a compiler warning.
322 8. Added four artifical Unicode properties to help with an option to make
323 \s etc use properties (see next item). The new properties are: Xan
324 (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
326 9. Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
327 use Unicode properties. (*UCP) at the start of a pattern can be used to set
328 this option. Modified pcretest to add /W to test this facility. Added
329 REG_UCP to make it available via the POSIX interface.
331 10. Added --line-buffered to pcregrep.
333 11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
334 studied, and the match started with a letter with a code point greater than
335 127 whose first byte was different to the first byte of the other case of
336 the letter, the other case of this starting letter was not recognized
337 (#976).
339 12. If a pattern that was studied started with a repeated Unicode property
340 test, for example, \p{Nd}+, there was the theoretical possibility of
341 setting up an incorrect bitmap of starting bytes, but fortunately it could
342 not have actually happened in practice until change 8 above was made (it
343 added property types that matched character-matching opcodes).
345 13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
346 possible starting bytes for non-anchored patterns.
348 14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
349 \R, and also a number of cases that involve Unicode properties, both
350 explicit and implicit when PCRE_UCP is set.
352 15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
353 input, it could crash or give wrong results if characters with values
354 greater than 0xc0 were present in the subject string. (Detail: it assumed
355 UTF-8 input when processing these items.)
357 16. Added a lot of (int) casts to avoid compiler warnings in systems where
358 size_t is 64-bit (#991).
360 17. Added a check for running out of memory when PCRE is compiled with
361 --disable-stack-for-recursion (#990).
363 18. If the last data line in a file for pcretest does not have a newline on
364 the end, a newline was missing in the output.
366 19. The default pcre_chartables.c file recognizes only ASCII characters (values
367 less than 128) in its various bitmaps. However, there is a facility for
368 generating tables according to the current locale when PCRE is compiled. It
369 turns out that in some environments, 0x85 and 0xa0, which are Unicode space
370 characters, are recognized by isspace() and therefore were getting set in
371 these tables, and indeed these tables seem to approximate to ISO 8859. This
372 caused a problem in UTF-8 mode when pcre_study() was used to create a list
373 of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
374 which of course cannot start UTF-8 characters. I have changed the code so
375 that only real ASCII characters (less than 128) and the correct starting
376 bytes for UTF-8 encodings are set for characters greater than 127 when in
377 UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
378 altogether.)
380 20. Added the /T option to pcretest so as to be able to run tests with non-
381 standard character tables, thus making it possible to include the tests
382 used for 19 above in the standard set of tests.
384 21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
385 reference to a subpattern the other side of a comment that contains an
386 opening parenthesis caused either an internal compiling error, or a
387 reference to the wrong subpattern.
390 Version 8.02 19-Mar-2010
391 ------------------------
393 1. The Unicode data tables have been updated to Unicode 5.2.0.
395 2. Added the option --libs-cpp to pcre-config, but only when C++ support is
396 configured.
398 3. Updated the licensing terms in the pcregexp.pas file, as agreed with the
399 original author of that file, following a query about its status.
401 4. On systems that do not have stdint.h (e.g. Solaris), check for and include
402 inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
404 5. A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
405 quantifier applied to a forward-referencing subroutine call, could compile
406 incorrect code or give the error "internal error: previously-checked
407 referenced subpattern not found".
409 6. Both MS Visual Studio and Symbian OS have problems with initializing
410 variables to point to external functions. For these systems, therefore,
411 pcre_malloc etc. are now initialized to local functions that call the
412 relevant global functions.
414 7. There were two entries missing in the vectors called coptable and poptable
415 in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
416 I've fixed the data, and added a kludgy way of testing at compile time that
417 the lengths are correct (equal to the number of opcodes).
419 8. Following on from 7, I added a similar kludge to check the length of the
420 eint vector in pcreposix.c.
422 9. Error texts for pcre_compile() are held as one long string to avoid too
423 much relocation at load time. To find a text, the string is searched,
424 counting zeros. There was no check for running off the end of the string,
425 which could happen if a new error number was added without updating the
426 string.
428 10. \K gave a compile-time error if it appeared in a lookbehind assersion.
430 11. \K was not working if it appeared in an atomic group or in a group that
431 was called as a "subroutine", or in an assertion. Perl 5.11 documents that
432 \K is "not well defined" if used in an assertion. PCRE now accepts it if
433 the assertion is positive, but not if it is negative.
435 12. Change 11 fortuitously reduced the size of the stack frame used in the
436 "match()" function of pcre_exec.c by one pointer. Forthcoming
437 implementation of support for (*MARK) will need an extra pointer on the
438 stack; I have reserved it now, so that the stack frame size does not
439 decrease.
441 13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
442 item in branch that calls a recursion is a subroutine call - as in the
443 second branch in the above example - was incorrectly given the compile-
444 time error "recursive call could loop indefinitely" because pcre_compile()
445 was not correctly checking the subroutine for matching a non-empty string.
447 14. The checks for overrunning compiling workspace could trigger after an
448 overrun had occurred. This is a "should never occur" error, but it can be
449 triggered by pathological patterns such as hundreds of nested parentheses.
450 The checks now trigger 100 bytes before the end of the workspace.
452 15. Fix typo in configure.ac: "srtoq" should be "strtoq".
455 Version 8.01 19-Jan-2010
456 ------------------------
458 1. If a pattern contained a conditional subpattern with only one branch (in
459 particular, this includes all (*DEFINE) patterns), a call to pcre_study()
460 computed the wrong minimum data length (which is of course zero for such
461 subpatterns). This could cause incorrect "no match" results.
463 2. For patterns such as (?i)a(?-i)b|c where an option setting at the start of
464 the pattern is reset in the first branch, pcre_compile() failed with
465 "internal error: code overflow at offset...". This happened only when
466 the reset was to the original external option setting. (An optimization
467 abstracts leading options settings into an external setting, which was the
468 cause of this.)
470 3. A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
471 of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
472 assertion pattern did not match (meaning that the assertion was true), it
473 was incorrectly treated as false if the SKIP had been reached during the
474 matching. This also applied to assertions used as conditions.
476 4. If an item that is not supported by pcre_dfa_exec() was encountered in an
477 assertion subpattern, including such a pattern used as a condition,
478 unpredictable results occurred, instead of the error return
481 5. The C++ GlobalReplace function was not working like Perl for the special
482 situation when an empty string is matched. It now does the fancy magic
483 stuff that is necessary.
485 6. In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
486 removed. (These were left over from very, very early versions of PCRE.)
488 7. Some cosmetic changes to the code to make life easier when compiling it
489 as part of something else:
491 (a) Change DEBUG to PCRE_DEBUG.
493 (b) In pcre_compile(), rename the member of the "branch_chain" structure
494 called "current" as "current_branch", to prevent a collision with the
495 Linux macro when compiled as a kernel module.
497 (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
498 prevent a collision with the Linux macro when compiled as a kernel
499 module.
501 8. In pcre_compile() there are some checks for integer overflows that used to
502 cast potentially large values to (double). This has been changed to that
503 when building, a check for int64_t is made, and if it is found, it is used
504 instead, thus avoiding the use of floating point arithmetic. (There is no
505 other use of FP in PCRE.) If int64_t is not found, the fallback is to
506 double.
508 9. Added two casts to avoid signed/unsigned warnings from VS Studio Express
509 2005 (difference between two addresses compared to an unsigned value).
511 10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
512 custom one, because of the following reported problem in Windows:
514 - libbz2 uses the Pascal calling convention (WINAPI) for the functions
515 under Win32.
516 - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
517 therefore missing the function definition.
518 - The compiler thus generates a "C" signature for the test function.
519 - The linker fails to find the "C" function.
520 - PCRE fails to configure if asked to do so against libbz2.
522 11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
523 messages were output:
525 Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
526 rerunning libtoolize, to keep the correct libtool macros in-tree.
527 Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
529 I have done both of these things.
531 12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
532 most of the time, it *can* run out if it is given a pattern that contains a
533 runaway infinite recursion. I updated the discussion in the pcrestack man
534 page.
536 13. Now that we have gone to the x.xx style of version numbers, the minor
537 version may start with zero. Using 08 or 09 is a bad idea because users
538 might check the value of PCRE_MINOR in their code, and 08 or 09 may be
539 interpreted as invalid octal numbers. I've updated the previous comment in
540 configure.ac, and also added a check that gives an error if 08 or 09 are
541 used.
543 14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
544 causing partial matching to fail when the end of the subject matched \W
545 in a UTF-8 pattern where \W was quantified with a minimum of 3.
547 15. There were some discrepancies between the declarations in pcre_internal.h
548 of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
549 their definitions. The declarations used "const uschar *" and the
550 definitions used USPTR. Even though USPTR is normally defined as "const
551 unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
552 reported that: "This difference in casting confuses some C++ compilers, for
553 example, SunCC recognizes above declarations as different functions and
554 generates broken code for hbpcre." I have changed the declarations to use
555 USPTR.
557 16. GNU libtool is named differently on some systems. The autogen.sh script now
558 tries several variants such as glibtoolize (MacOSX) and libtoolize1x
559 (FreeBSD).
561 17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
562 (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
563 comment: "Figure out how to create a longlong from a string: strtoll and
564 equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
565 instance, but it only takes 2 args instead of 3!"
567 18. A subtle bug concerned with back references has been fixed by a change of
568 specification, with a corresponding code fix. A pattern such as
569 ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
570 refers, was giving matches when it shouldn't. For example, xa=xaaa would
571 match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
572 same bug. Such groups have to be quantified to be useful, or contained
573 inside another quantified group. (If there's no repetition, the reference
574 can never match.) The problem arises because, having left the group and
575 moved on to the rest of the pattern, a later failure that backtracks into
576 the group uses the captured value from the final iteration of the group
577 rather than the correct earlier one. I have fixed this in PCRE by forcing
578 any group that contains a reference to itself to be an atomic group; that
579 is, there cannot be any backtracking into it once it has completed. This is
580 similar to recursive and subroutine calls.
583 Version 8.00 19-Oct-09
584 ----------------------
586 1. The table for translating pcre_compile() error codes into POSIX error codes
587 was out-of-date, and there was no check on the pcre_compile() error code
588 being within the table. This could lead to an OK return being given in
589 error.
591 2. Changed the call to open a subject file in pcregrep from fopen(pathname,
592 "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
593 in a Windows environment.
595 3. The pcregrep --count option prints the count for each file even when it is
596 zero, as does GNU grep. However, pcregrep was also printing all files when
597 --files-with-matches was added. Now, when both options are given, it prints
598 counts only for those files that have at least one match. (GNU grep just
599 prints the file name in this circumstance, but including the count seems
600 more useful - otherwise, why use --count?) Also ensured that the
601 combination -clh just lists non-zero counts, with no names.
603 4. The long form of the pcregrep -F option was incorrectly implemented as
604 --fixed_strings instead of --fixed-strings. This is an incompatible change,
605 but it seems right to fix it, and I didn't think it was worth preserving
606 the old behaviour.
608 5. The command line items --regex=pattern and --regexp=pattern were not
609 recognized by pcregrep, which required --regex pattern or --regexp pattern
610 (with a space rather than an '='). The man page documented the '=' forms,
611 which are compatible with GNU grep; these now work.
613 6. No libpcreposix.pc file was created for pkg-config; there was just
614 libpcre.pc and libpcrecpp.pc. The omission has been rectified.
616 7. Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
617 when UCP support is not needed, by modifying the Python script that
618 generates it from Unicode data files. This should not matter if the module
619 is correctly used as a library, but I received one complaint about 50K of
620 unwanted data. My guess is that the person linked everything into his
621 program rather than using a library. Anyway, it does no harm.
623 8. A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
624 was a minimum greater than 1 for a wide character in a possessive
625 repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
626 which had an unlimited repeat of a nested, fixed maximum repeat of a wide
627 character. Chaos in the form of incorrect output or a compiling loop could
628 result.
630 9. The restrictions on what a pattern can contain when partial matching is
631 requested for pcre_exec() have been removed. All patterns can now be
632 partially matched by this function. In addition, if there are at least two
633 slots in the offset vector, the offset of the earliest inspected character
634 for the match and the offset of the end of the subject are set in them when
635 PCRE_ERROR_PARTIAL is returned.
637 10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
638 synonymous with PCRE_PARTIAL, for backwards compatibility, and
639 PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
640 and may be more useful for multi-segment matching.
642 11. Partial matching with pcre_exec() is now more intuitive. A partial match
643 used to be given if ever the end of the subject was reached; now it is
644 given only if matching could not proceed because another character was
645 needed. This makes a difference in some odd cases such as Z(*FAIL) with the
646 string "Z", which now yields "no match" instead of "partial match". In the
647 case of pcre_dfa_exec(), "no match" is given if every matching path for the
648 final character ended with (*FAIL).
650 12. Restarting a match using pcre_dfa_exec() after a partial match did not work
651 if the pattern had a "must contain" character that was already found in the
652 earlier partial match, unless partial matching was again requested. For
653 example, with the pattern /dog.(body)?/, the "must contain" character is
654 "g". If the first part-match was for the string "dog", restarting with
655 "sbody" failed. This bug has been fixed.
657 13. The string returned by pcre_dfa_exec() after a partial match has been
658 changed so that it starts at the first inspected character rather than the
659 first character of the match. This makes a difference only if the pattern
660 starts with a lookbehind assertion or \b or \B (\K is not supported by
661 pcre_dfa_exec()). It's an incompatible change, but it makes the two
662 matching functions compatible, and I think it's the right thing to do.
664 14. Added a pcredemo man page, created automatically from the pcredemo.c file,
665 so that the demonstration program is easily available in environments where
666 PCRE has not been installed from source.
668 15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
669 libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
670 library.
672 16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
673 It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
674 is not the first non-POSIX option to be added. Clearly some people find
675 these options useful.
677 17. If a caller to the POSIX matching function regexec() passes a non-zero
678 value for nmatch with a NULL value for pmatch, the value of
679 nmatch is forced to zero.
681 18. RunGrepTest did not have a test for the availability of the -u option of
682 the diff command, as RunTest does. It now checks in the same way as
683 RunTest, and also checks for the -b option.
685 19. If an odd number of negated classes containing just a single character
686 interposed, within parentheses, between a forward reference to a named
687 subpattern and the definition of the subpattern, compilation crashed with
688 an internal error, complaining that it could not find the referenced
689 subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
690 [The bug was that it was starting one character too far in when skipping
691 over the character class, thus treating the ] as data rather than
692 terminating the class. This meant it could skip too much.]
694 20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
695 /g option in pcretest when the pattern contains \K, which makes it possible
696 to have an empty string match not at the start, even when the pattern is
697 anchored. Updated pcretest and pcredemo to use this option.
699 21. If the maximum number of capturing subpatterns in a recursion was greater
700 than the maximum at the outer level, the higher number was returned, but
701 with unset values at the outer level. The correct (outer level) value is
702 now given.
704 22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
705 PCRE did not set those parentheses (unlike Perl). I have now found a way to
706 make it do so. The string so far is captured, making this feature
707 compatible with Perl.
709 23. The tests have been re-organized, adding tests 11 and 12, to make it
710 possible to check the Perl 5.10 features against Perl 5.10.
712 24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
713 pattern matches a fixed length string. PCRE did not allow this; now it
714 does. Neither allows recursion.
716 25. I finally figured out how to implement a request to provide the minimum
717 length of subject string that was needed in order to match a given pattern.
718 (It was back references and recursion that I had previously got hung up
719 on.) This code has now been added to pcre_study(); it finds a lower bound
720 to the length of subject needed. It is not necessarily the greatest lower
721 bound, but using it to avoid searching strings that are too short does give
722 some useful speed-ups. The value is available to calling programs via
723 pcre_fullinfo().
725 26. While implementing 25, I discovered to my embarrassment that pcretest had
726 not been passing the result of pcre_study() to pcre_dfa_exec(), so the
727 study optimizations had never been tested with that matching function.
728 Oops. What is worse, even when it was passed study data, there was a bug in
729 pcre_dfa_exec() that meant it never actually used it. Double oops. There
730 were also very few tests of studied patterns with pcre_dfa_exec().
732 27. If (?| is used to create subpatterns with duplicate numbers, they are now
733 allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
734 on the other side of the coin, they are no longer allowed to have different
735 names, because these cannot be distinguished in PCRE, and this has caused
736 confusion. (This is a difference from Perl.)
738 28. When duplicate subpattern names are present (necessarily with different
739 numbers, as required by 27 above), and a test is made by name in a
740 conditional pattern, either for a subpattern having been matched, or for
741 recursion in such a pattern, all the associated numbered subpatterns are
742 tested, and the overall condition is true if the condition is true for any
743 one of them. This is the way Perl works, and is also more like the way
744 testing by number works.
747 Version 7.9 11-Apr-09
748 ---------------------
750 1. When building with support for bzlib/zlib (pcregrep) and/or readline
751 (pcretest), all targets were linked against these libraries. This included
752 libpcre, libpcreposix, and libpcrecpp, even though they do not use these
753 libraries. This caused unwanted dependencies to be created. This problem
754 has been fixed, and now only pcregrep is linked with bzlib/zlib and only
755 pcretest is linked with readline.
757 2. The "typedef int BOOL" in pcre_internal.h that was included inside the
758 "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
759 moved outside it again, because FALSE and TRUE are already defined in AIX,
760 but BOOL is not.
762 3. The pcre_config() function was treating the PCRE_MATCH_LIMIT and
763 PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
765 4. The pcregrep documentation said spaces were inserted as well as colons (or
766 hyphens) following file names and line numbers when outputting matching
767 lines. This is not true; no spaces are inserted. I have also clarified the
768 wording for the --colour (or --color) option.
770 5. In pcregrep, when --colour was used with -o, the list of matching strings
771 was not coloured; this is different to GNU grep, so I have changed it to be
772 the same.
774 6. When --colo(u)r was used in pcregrep, only the first matching substring in
775 each matching line was coloured. Now it goes on to look for further matches
776 of any of the test patterns, which is the same behaviour as GNU grep.
778 7. A pattern that could match an empty string could cause pcregrep to loop; it
779 doesn't make sense to accept an empty string match in pcregrep, so I have
780 locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
781 seems to be how GNU grep behaves.
783 8. The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
784 start or after a newline", because the conditional assertion was not being
785 correctly handled. The rule now is that both the assertion and what follows
786 in the first alternative must satisfy the test.
788 9. If auto-callout was enabled in a pattern with a conditional group whose
789 condition was an assertion, PCRE could crash during matching, both with
790 pcre_exec() and pcre_dfa_exec().
792 10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
793 used for matching.
795 11. Unicode property support in character classes was not working for
796 characters (bytes) greater than 127 when not in UTF-8 mode.
798 12. Added the -M command line option to pcretest.
800 14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
802 15. Added the PCRE_NO_START_OPTIMIZE match-time option.
804 16. Added comments and documentation about mis-use of no_arg in the C++
805 wrapper.
807 17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
808 from Martin Jerabek that uses macro names for all relevant character and
809 string constants.
811 18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
812 SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
813 SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
814 these, but not everybody uses configure.
816 19. A conditional group that had only one branch was not being correctly
817 recognized as an item that could match an empty string. This meant that an
818 enclosing group might also not be so recognized, causing infinite looping
819 (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
820 with the subject "ab", where knowledge that the repeated group can match
821 nothing is needed in order to break the loop.
823 20. If a pattern that was compiled with callouts was matched using pcre_dfa_
824 exec(), but without supplying a callout function, matching went wrong.
826 21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
827 leak if the size of the offset vector was greater than 30. When the vector
828 is smaller, the saved offsets during recursion go onto a local stack
829 vector, but for larger vectors malloc() is used. It was failing to free
830 when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
831 error, in fact).
833 22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
834 heapframe that is used only when UTF-8 support is enabled. This caused no
835 problem, but was untidy.
837 23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
838 CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
839 included within another project.
841 24. Steven Van Ingelgem's patches to add more options to the CMake support,
842 slightly modified by me:
844 (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
845 not building pcregrep.
847 (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
848 if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
850 25. Forward references, both numeric and by name, in patterns that made use of
851 duplicate group numbers, could behave incorrectly or give incorrect errors,
852 because when scanning forward to find the reference group, PCRE was not
853 taking into account the duplicate group numbers. A pattern such as
854 ^X(?3)(a)(?|(b)|(q))(Y) is an example.
856 26. Changed a few more instances of "const unsigned char *" to USPTR, making
857 the feature of a custom pointer more persuasive (as requested by a user).
859 27. Wrapped the definitions of fileno and isatty for Windows, which appear in
860 pcretest.c, inside #ifndefs, because it seems they are sometimes already
861 pre-defined.
863 28. Added support for (*UTF8) at the start of a pattern.
865 29. Arrange for flags added by the "release type" setting in CMake to be shown
866 in the configuration summary.
869 Version 7.8 05-Sep-08
870 ---------------------
872 1. Replaced UCP searching code with optimized version as implemented for Ad
873 Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
874 stage table and inline lookup instead of a function, giving speed ups of 2
875 to 5 times on some simple patterns that I tested. Permission was given to
876 distribute the MultiStage2.py script that generates the tables (it's not in
877 the tarball, but is in the Subversion repository).
879 2. Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
880 scripts.
882 3. Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
883 a group with a zero qualifier. The result of the study could be incorrect,
884 or the function might crash, depending on the pattern.
886 4. Caseless matching was not working for non-ASCII characters in back
887 references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
888 It now works when Unicode Property Support is available.
890 5. In pcretest, an escape such as \x{de} in the data was always generating
891 a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
892 non-UTF-8 mode. If the value is greater than 255, it gives a warning about
893 truncation.
895 6. Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
897 7. Added two (int) casts to pcregrep when printing the difference of two
898 pointers, in case they are 64-bit values.
900 8. Added comments about Mac OS X stack usage to the pcrestack man page and to
901 test 2 if it fails.
903 9. Added PCRE_CALL_CONVENTION just before the names of all exported functions,
904 and a #define of that name to empty if it is not externally set. This is to
905 allow users of MSVC to set it if necessary.
907 10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
908 the convenience functions in the pcre_get.c source file.
910 11. An option change at the start of a pattern that had top-level alternatives
911 could cause overwriting and/or a crash. This command provoked a crash in
912 some environments:
914 printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
916 This potential security problem was recorded as CVE-2008-2371.
918 12. For a pattern where the match had to start at the beginning or immediately
919 after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
920 pcre_dfa_exec() could read past the end of the passed subject if there was
921 no match. To help with detecting such bugs (e.g. with valgrind), I modified
922 pcretest so that it places the subject at the end of its malloc-ed buffer.
924 13. The change to pcretest in 12 above threw up a couple more cases when pcre_
925 exec() might read past the end of the data buffer in UTF-8 mode.
927 14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
928 the data contained the byte 0x85 as part of a UTF-8 character within its
929 first line. This applied both to normal and DFA matching.
931 15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
932 /^[^d]*?$/8 failed to match "abc".
934 16. Added a missing copyright notice to pcrecpp_internal.h.
936 17. Make it more clear in the documentation that values returned from
937 pcre_exec() in ovector are byte offsets, not character counts.
939 18. Tidied a few places to stop certain compilers from issuing warnings.
941 19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
942 supplied by Stefan Weber. I made a further small update for 7.8 because
943 there is a change of source arrangements: the pcre_searchfuncs.c module is
944 replaced by pcre_ucd.c.
947 Version 7.7 07-May-08
948 ---------------------
950 1. Applied Craig's patch to sort out a long long problem: "If we can't convert
951 a string to a long long, pretend we don't even have a long long." This is
952 done by checking for the strtoq, strtoll, and _strtoi64 functions.
954 2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
955 pre-7.6 versions, which defined a global no_arg variable instead of putting
956 it in the RE class. (See also #8 below.)
958 3. Remove a line of dead code, identified by coverity and reported by Nuno
959 Lopes.
961 4. Fixed two related pcregrep bugs involving -r with --include or --exclude:
963 (1) The include/exclude patterns were being applied to the whole pathnames
964 of files, instead of just to the final components.
966 (2) If there was more than one level of directory, the subdirectories were
967 skipped unless they satisfied the include/exclude conditions. This is
968 inconsistent with GNU grep (and could even be seen as contrary to the
969 pcregrep specification - which I improved to make it absolutely clear).
970 The action now is always to scan all levels of directory, and just
971 apply the include/exclude patterns to regular files.
973 5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used
974 --exclude_dir in the tests to avoid scanning .svn directories.
976 6. Applied Craig's patch to the QuoteMeta function so that it escapes the
977 NUL character as backslash + 0 rather than backslash + NUL, because PCRE
978 doesn't support NULs in patterns.
980 7. Added some missing "const"s to declarations of static tables in
981 pcre_compile.c and pcre_dfa_exec.c.
983 8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
984 caused by fix #2 above. (Subsequently also a second patch to fix the
985 first patch. And a third patch - this was a messy problem.)
987 9. Applied Craig's patch to remove the use of push_back().
989 10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
990 matching function regexec().
992 11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
993 which, however, unlike Perl's \g{...}, are subroutine calls, not back
994 references. PCRE supports relative numbers with this syntax (I don't think
995 Oniguruma does).
997 12. Previously, a group with a zero repeat such as (...){0} was completely
998 omitted from the compiled regex. However, this means that if the group
999 was called as a subroutine from elsewhere in the pattern, things went wrong
1000 (an internal error was given). Such groups are now left in the compiled
1001 pattern, with a new opcode that causes them to be skipped at execution
1002 time.
1004 13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
1005 to the way PCRE behaves:
1007 (a) A lone ] character is dis-allowed (Perl treats it as data).
1009 (b) A back reference to an unmatched subpattern matches an empty string
1010 (Perl fails the current match path).
1012 (c) A data ] in a character class must be notated as \] because if the
1013 first data character in a class is ], it defines an empty class. (In
1014 Perl it is not possible to have an empty class.) The empty class []
1015 never matches; it forces failure and is equivalent to (*FAIL) or (?!).
1016 The negative empty class [^] matches any one character, independently
1017 of the DOTALL setting.
1019 14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
1020 non-existent subpattern following a character class starting with ']' and
1021 containing () gave an internal compiling error instead of "reference to
1022 non-existent subpattern". Fortunately, when the pattern did exist, the
1023 compiled code was correct. (When scanning forwards to check for the
1024 existencd of the subpattern, it was treating the data ']' as terminating
1025 the class, so got the count wrong. When actually compiling, the reference
1026 was subsequently set up correctly.)
1028 15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
1029 it was being rejected as not supported by pcre_dfa_exec(), even though
1030 other assertions are supported. I have made pcre_dfa_exec() support
1031 (*FAIL).
1033 16. The implementation of 13c above involved the invention of a new opcode,
1034 OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
1035 cannot be changed at match time, I realized I could make a small
1036 improvement to matching performance by compiling OP_ALLANY instead of
1037 OP_ANY for "." when DOTALL was set, and then removing the runtime tests
1038 on the OP_ANY path.
1040 17. Compiling pcretest on Windows with readline support failed without the
1041 following two fixes: (1) Make the unistd.h include conditional on
1042 HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
1044 18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
1045 ncurses library to be included for pcretest when ReadLine support is
1046 requested, but also to allow for it to be overridden. This patch came from
1047 Daniel Bergström.
1049 19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
1050 as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
1051 any errors with the current Unicode tables. Thanks to Peter Kankowski for
1052 spotting this.
1055 Version 7.6 28-Jan-08
1056 ---------------------
1058 1. A character class containing a very large number of characters with
1059 codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
1060 overflow.
1062 2. Patch to cut out the "long long" test in pcrecpp_unittest when
1063 HAVE_LONG_LONG is not defined.
1065 3. Applied Christian Ehrlicher's patch to update the CMake build files to
1066 bring them up to date and include new features. This patch includes:
1068 - Fixed PH's badly added libz and libbz2 support.
1069 - Fixed a problem with static linking.
1070 - Added pcredemo. [But later removed - see 7 below.]
1071 - Fixed dftables problem and added an option.
1072 - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
1074 - Added readline support for pcretest.
1075 - Added an listing of the option settings after cmake has run.
1077 4. A user submitted a patch to Makefile that makes it easy to create
1078 "pcre.dll" under mingw when using Configure/Make. I added stuff to
1079 Makefile.am that cause it to include this special target, without
1080 affecting anything else. Note that the same mingw target plus all
1081 the other distribution libraries and programs are now supported
1082 when configuring with CMake (see 6 below) instead of with
1083 Configure/Make.
1085 5. Applied Craig's patch that moves no_arg into the RE class in the C++ code.
1086 This is an attempt to solve the reported problem "pcrecpp::no_arg is not
1087 exported in the Windows port". It has not yet been confirmed that the patch
1088 solves the problem, but it does no harm.
1090 6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
1091 NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
1092 with CMake, and also correct the comment about stack recursion.
1094 7. Remove the automatic building of pcredemo from the ./configure system and
1095 from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
1096 of a program that users should build themselves after PCRE is installed, so
1097 building it automatically is not really right. What is more, it gave
1098 trouble in some build environments.
1100 8. Further tidies to CMakeLists.txt from Sheri and Christian.
1103 Version 7.5 10-Jan-08
1104 ---------------------
1106 1. Applied a patch from Craig: "This patch makes it possible to 'ignore'
1107 values in parens when parsing an RE using the C++ wrapper."
1109 2. Negative specials like \S did not work in character classes in UTF-8 mode.
1110 Characters greater than 255 were excluded from the class instead of being
1111 included.
1113 3. The same bug as (2) above applied to negated POSIX classes such as
1114 [:^space:].
1116 4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
1117 defined or documented. It seems to have been a typo for PCRE_STATIC, so
1118 I have changed it.
1120 5. The construct (?&) was not diagnosed as a syntax error (it referenced the
1121 first named subpattern) and a construct such as (?&a) would reference the
1122 first named subpattern whose name started with "a" (in other words, the
1123 length check was missing). Both these problems are fixed. "Subpattern name
1124 expected" is now given for (?&) (a zero-length name), and this patch also
1125 makes it give the same error for \k'' (previously it complained that that
1126 was a reference to a non-existent subpattern).
1128 6. The erroneous patterns (?+-a) and (?-+a) give different error messages;
1129 this is right because (?- can be followed by option settings as well as by
1130 digits. I have, however, made the messages clearer.
1132 7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
1133 than the number used in the conditional) now cause a compile-time error.
1134 This is actually not compatible with Perl, which accepts such patterns, but
1135 treats the conditional as always being FALSE (as PCRE used to), but it
1136 seems to me that giving a diagnostic is better.
1138 8. Change "alphameric" to the more common word "alphanumeric" in comments
1139 and messages.
1141 9. Fix two occurrences of "backslash" in comments that should have been
1142 "backspace".
1144 10. Remove two redundant lines of code that can never be obeyed (their function
1145 was moved elsewhere).
1147 11. The program that makes PCRE's Unicode character property table had a bug
1148 which caused it to generate incorrect table entries for sequences of
1149 characters that have the same character type, but are in different scripts.
1150 It amalgamated them into a single range, with the script of the first of
1151 them. In other words, some characters were in the wrong script. There were
1152 thirteen such cases, affecting characters in the following ranges:
1154 U+002b0 - U+002c1
1155 U+0060c - U+0060d
1156 U+0061e - U+00612
1157 U+0064b - U+0065e
1158 U+0074d - U+0076d
1159 U+01800 - U+01805
1160 U+01d00 - U+01d77
1161 U+01d9b - U+01dbf
1162 U+0200b - U+0200f
1163 U+030fc - U+030fe
1164 U+03260 - U+0327f
1165 U+0fb46 - U+0fbb1
1166 U+10450 - U+1049d
1168 12. The -o option (show only the matching part of a line) for pcregrep was not
1169 compatible with GNU grep in that, if there was more than one match in a
1170 line, it showed only the first of them. It now behaves in the same way as
1171 GNU grep.
1173 13. If the -o and -v options were combined for pcregrep, it printed a blank
1174 line for every non-matching line. GNU grep prints nothing, and pcregrep now
1175 does the same. The return code can be used to tell if there were any
1176 non-matching lines.
1178 14. Added --file-offsets and --line-offsets to pcregrep.
1180 15. The pattern (?=something)(?R) was not being diagnosed as a potentially
1181 infinitely looping recursion. The bug was that positive lookaheads were not
1182 being skipped when checking for a possible empty match (negative lookaheads
1183 and both kinds of lookbehind were skipped).
1185 16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
1186 inclusion of <windows.h> to before rather than after the definition of
1187 INVALID_FILE_ATTRIBUTES (patch from David Byron).
1189 17. Specifying a possessive quantifier with a specific limit for a Unicode
1190 character property caused pcre_compile() to compile bad code, which led at
1191 runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
1192 are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
1193 caused the error; without that there was no problem.
1195 18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
1197 19. Added --enable-pcretest-libreadline.
1199 20. In pcrecpp.cc, the variable 'count' was incremented twice in
1200 RE::GlobalReplace(). As a result, the number of replacements returned was
1201 double what it should be. I removed one of the increments, but Craig sent a
1202 later patch that removed the other one (the right fix) and added unit tests
1203 that check the return values (which was not done before).
1205 21. Several CMake things:
1207 (1) Arranged that, when cmake is used on Unix, the libraries end up with
1208 the names libpcre and libpcreposix, not just pcre and pcreposix.
1210 (2) The above change means that pcretest and pcregrep are now correctly
1211 linked with the newly-built libraries, not previously installed ones.
1215 22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
1216 crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
1217 UTF-8 newline character). The key issue is that the pattern starts .*;
1218 this means that the match must be either at the beginning, or after a
1219 newline. The bug was in the code for advancing after a failed match and
1220 checking that the new position followed a newline. It was not taking
1221 account of UTF-8 characters correctly.
1223 23. PCRE was behaving differently from Perl in the way it recognized POSIX
1224 character classes. PCRE was not treating the sequence [:...:] as a
1225 character class unless the ... were all letters. Perl, however, seems to
1226 allow any characters between [: and :], though of course it rejects as
1227 unknown any "names" that contain non-letters, because all the known class
1228 names consist only of letters. Thus, Perl gives an error for [[:1234:]],
1229 for example, whereas PCRE did not - it did not recognize a POSIX character
1230 class. This seemed a bit dangerous, so the code has been changed to be
1231 closer to Perl. The behaviour is not identical to Perl, because PCRE will
1232 diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
1233 treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
1234 Perl does, and where it didn't before.
1236 24. Rewrite so as to remove the single use of %n from pcregrep because in some
1237 Windows environments %n is disabled by default.
1240 Version 7.4 21-Sep-07
1241 ---------------------
1243 1. Change 7.3/28 was implemented for classes by looking at the bitmap. This
1244 means that a class such as [\s] counted as "explicit reference to CR or
1245 LF". That isn't really right - the whole point of the change was to try to
1246 help when there was an actual mention of one of the two characters. So now
1247 the change happens only if \r or \n (or a literal CR or LF) character is
1248 encountered.
1250 2. The 32-bit options word was also used for 6 internal flags, but the numbers
1251 of both had grown to the point where there were only 3 bits left.
1252 Fortunately, there was spare space in the data structure, and so I have
1253 moved the internal flags into a new 16-bit field to free up more option
1254 bits.
1256 3. The appearance of (?J) at the start of a pattern set the DUPNAMES option,
1257 but did not set the internal JCHANGED flag - either of these is enough to
1258 control the way the "get" function works - but the PCRE_INFO_JCHANGED
1259 facility is supposed to tell if (?J) was ever used, so now (?J) at the
1260 start sets both bits.
1262 4. Added options (at build time, compile time, exec time) to change \R from
1263 matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
1265 5. doc/pcresyntax.html was missing from the distribution.
1267 6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
1268 compatibility, even though it is no longer used.
1270 7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
1271 strtoull to pcrecpp.cc to select the available functions in WIN32 when the
1272 windows.h file is present (where different names are used). [This was
1273 reversed later after testing - see 16 below.]
1275 8. Changed all #include <config.h> to #include "config.h". There were also
1276 some further <pcre.h> cases that I changed to "pcre.h".
1278 9. When pcregrep was used with the --colour option, it missed the line ending
1279 sequence off the lines that it output.
1281 10. It was pointed out to me that arrays of string pointers cause lots of
1282 relocations when a shared library is dynamically loaded. A technique of
1283 using a single long string with a table of offsets can drastically reduce
1284 these. I have refactored PCRE in four places to do this. The result is
1285 dramatic:
1287 Originally: 290
1288 After changing UCP table: 187
1289 After changing error message table: 43
1290 After changing table of "verbs" 36
1291 After changing table of Posix names 22
1293 Thanks to the folks working on Gregex for glib for this insight.
1295 11. --disable-stack-for-recursion caused compiling to fail unless -enable-
1296 unicode-properties was also set.
1298 12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
1300 13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
1301 checked only for CRLF.
1303 14. Added casts to pcretest.c to avoid compiler warnings.
1305 15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
1307 16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
1308 and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
1309 entirely. This removes changes made in 7 above.
1311 17. The CMake files have been updated, and there is now more information about
1312 building with CMake in the NON-UNIX-USE document.
1315 Version 7.3 28-Aug-07
1316 ---------------------
1318 1. In the rejigging of the build system that eventually resulted in 7.1, the
1319 line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
1320 brackets there is not right, since it causes compilers to look for an
1321 installed pcre.h, not the version that is in the source that is being
1322 compiled (which of course may be different). I have changed it back to:
1324 #include "pcre.h"
1326 I have a vague recollection that the change was concerned with compiling in
1327 different directories, but in the new build system, that is taken care of
1328 by the VPATH setting the Makefile.
1330 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
1331 when the subject happened to end in the byte 0x85 (e.g. if the last
1332 character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
1333 characters but of course it shouldn't be taken as a newline when it is part
1334 of another character. The bug was that, for an unlimited repeat of . in
1335 not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
1336 characters when looking for a newline.
1338 3. A small performance improvement in the DOTALL UTF-8 mode .* case.
1340 4. Debugging: adjusted the names of opcodes for different kinds of parentheses
1341 in debug output.
1343 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
1344 long printing in the pcrecpp unittest when running under MinGW.
1346 6. ESC_K was left out of the EBCDIC table.
1348 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
1349 parentheses; I made it 1000, which seemed large enough. Unfortunately, the
1350 limit also applies to "virtual nesting" when a pattern is recursive, and in
1351 this case 1000 isn't so big. I have been able to remove this limit at the
1352 expense of backing off one optimization in certain circumstances. Normally,
1353 when pcre_exec() would call its internal match() function recursively and
1354 immediately return the result unconditionally, it uses a "tail recursion"
1355 feature to save stack. However, when a subpattern that can match an empty
1356 string has an unlimited repetition quantifier, it no longer makes this
1357 optimization. That gives it a stack frame in which to save the data for
1358 checking that an empty string has been matched. Previously this was taken
1359 from the 1000-entry workspace that had been reserved. So now there is no
1360 explicit limit, but more stack is used.
1362 8. Applied Daniel's patches to solve problems with the import/export magic
1363 syntax that is required for Windows, and which was going wrong for the
1364 pcreposix and pcrecpp parts of the library. These were overlooked when this
1365 problem was solved for the main library.
1367 9. There were some crude static tests to avoid integer overflow when computing
1368 the size of patterns that contain repeated groups with explicit upper
1369 limits. As the maximum quantifier is 65535, the maximum group length was
1370 set at 30,000 so that the product of these two numbers did not overflow a
1371 32-bit integer. However, it turns out that people want to use groups that
1372 are longer than 30,000 bytes (though not repeat them that many times).
1373 Change 7.0/17 (the refactoring of the way the pattern size is computed) has
1374 made it possible to implement the integer overflow checks in a much more
1375 dynamic way, which I have now done. The artificial limitation on group
1376 length has been removed - we now have only the limit on the total length of
1377 the compiled pattern, which depends on the LINK_SIZE setting.
1379 10. Fixed a bug in the documentation for get/copy named substring when
1380 duplicate names are permitted. If none of the named substrings are set, the
1381 functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
1382 empty string.
1384 11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
1385 instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
1386 because the ] is interpreted as the first data character and the
1387 terminating ] is not found. PCRE has been made compatible with Perl in this
1388 regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
1389 cause memory overwriting.
1391 10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
1392 string has been matched (to stop an infinite loop). It was not recognizing
1393 a conditional subpattern that could match an empty string if that
1394 subpattern was within another subpattern. For example, it looped when
1395 trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the
1396 condition was not nested. This bug has been fixed.
1398 12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
1399 past the start of the subject in the presence of bytes with the top bit
1400 set, for example "\x8aBCD".
1402 13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
1403 (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
1405 14. Optimized (?!) to (*FAIL).
1407 15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
1408 This restricts code points to be within the range 0 to 0x10FFFF, excluding
1409 the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
1410 full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
1411 does: it's just the validity check that is more restrictive.
1413 16. Inserted checks for integer overflows during escape sequence (backslash)
1414 processing, and also fixed erroneous offset values for syntax errors during
1415 backslash processing.
1417 17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
1418 for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
1420 18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
1421 caused an overrun.
1423 19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
1424 something other than just ASCII characters) inside a group that had an
1425 unlimited repeat caused a loop at compile time (while checking to see
1426 whether the group could match an empty string).
1428 20. Debugging a pattern containing \p or \P could cause a crash. For example,
1429 [\P{Any}] did so. (Error in the code for printing property names.)
1431 21. An orphan \E inside a character class could cause a crash.
1433 22. A repeated capturing bracket such as (A)? could cause a wild memory
1434 reference during compilation.
1436 23. There are several functions in pcre_compile() that scan along a compiled
1437 expression for various reasons (e.g. to see if it's fixed length for look
1438 behind). There were bugs in these functions when a repeated \p or \P was
1439 present in the pattern. These operators have additional parameters compared
1440 with \d, etc, and these were not being taken into account when moving along
1441 the compiled data. Specifically:
1443 (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
1444 length.
1446 (b) An item such as \pL+ within a repeated group could cause crashes or
1447 loops.
1449 (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
1450 "reference to non-existent subpattern" error.
1452 (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
1454 24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
1455 characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
1457 25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
1459 26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
1460 character were causing crashes (broken optimization).
1462 27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
1463 \p or \P) caused a compile-time loop.
1465 28. More problems have arisen in unanchored patterns when CRLF is a valid line
1466 break. For example, the unstudied pattern [\r\n]A does not match the string
1467 "\r\nA" because change 7.0/46 below moves the current point on by two
1468 characters after failing to match at the start. However, the pattern \nA
1469 *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
1470 the same is true. There doesn't seem any very clean way out of this, but
1471 what I have chosen to do makes the common cases work: PCRE now takes note
1472 of whether there can be an explicit match for \r or \n anywhere in the
1473 pattern, and if so, 7.0/46 no longer applies. As part of this change,
1474 there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
1475 pattern has explicit CR or LF references.
1477 29. Added (*CR) etc for changing newline setting at start of pattern.
1480 Version 7.2 19-Jun-07
1481 ---------------------
1483 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
1484 which is apparently normally available under Windows.
1486 2. Re-jig the pcregrep tests with different newline settings in an attempt
1487 to make them independent of the local environment's newline setting.
1489 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
1491 4. Some of the "internals" tests were previously cut out when the link size
1492 was not 2, because the output contained actual offsets. The recent new
1493 "Z" feature of pcretest means that these can be cut out, making the tests
1494 usable with all link sizes.
1496 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
1497 stack recursion. This gives a massive performance boost under BSD, but just
1498 a small improvement under Linux. However, it saves one field in the frame
1499 in all cases.
1501 6. Added more features from the forthcoming Perl 5.10:
1503 (a) (?-n) (where n is a string of digits) is a relative subroutine or
1504 recursion call. It refers to the nth most recently opened parentheses.
1506 (b) (?+n) is also a relative subroutine call; it refers to the nth next
1507 to be opened parentheses.
1509 (c) Conditions that refer to capturing parentheses can be specified
1510 relatively, for example, (?(-2)... or (?(+3)...
1512 (d) \K resets the start of the current match so that everything before
1513 is not part of it.
1515 (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
1517 (f) \g{name} is another synonym - part of Perl 5.10's unification of
1518 reference syntax.
1520 (g) (?| introduces a group in which the numbering of parentheses in each
1521 alternative starts with the same number.
1523 (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
1525 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
1528 8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not
1529 terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
1530 for detecting groups that can match an empty string.
1532 9. A pattern with a very large number of alternatives (more than several
1533 hundred) was running out of internal workspace during the pre-compile
1534 phase, where pcre_compile() figures out how much memory will be needed. A
1535 bit of new cunning has reduced the workspace needed for groups with
1536 alternatives. The 1000-alternative test pattern now uses 12 bytes of
1537 workspace instead of running out of the 4096 that are available.
1539 10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
1541 11. Applied patch from Google to remove an optimization that didn't quite work.
1542 The report of the bug said:
1544 pcrecpp::RE("a*").FullMatch("aaa") matches, while
1545 pcrecpp::RE("a*?").FullMatch("aaa") does not, and
1546 pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
1548 12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
1549 it matched the wrong number of bytes.
1552 Version 7.1 24-Apr-07
1553 ---------------------
1555 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
1556 that is more "standard", making use of automake and other Autotools. There
1557 is some re-arrangement of the files and adjustment of comments consequent
1558 on this.
1560 2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
1561 for recursive directory scanning broke on some systems because the files
1562 are not scanned in any specific order and on different systems the order
1563 was different. A call to "sort" has been inserted into RunGrepTest for the
1564 approprate test as a short-term fix. In the longer term there may be an
1565 alternative.
1567 3. I had an email from Eric Raymond about problems translating some of PCRE's
1568 man pages to HTML (despite the fact that I distribute HTML pages, some
1569 people do their own conversions for various reasons). The problems
1570 concerned the use of low-level troff macros .br and .in. I have therefore
1571 removed all such uses from the man pages (some were redundant, some could
1572 be replaced by .nf/.fi pairs). The 132html script that I use to generate
1573 HTML has been updated to handle .nf/.fi and to complain if it encounters
1574 .br or .in.
1576 4. Updated comments in configure.ac that get placed in config.h.in and also
1577 arranged for config.h to be included in the distribution, with the name
1578 config.h.generic, for the benefit of those who have to compile without
1579 Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
1581 5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
1582 Weber: (1) pcre_internal.h was missing some function renames; (2) updated
1583 makevp.bat for the current PCRE, using the additional files
1584 makevp_c.txt, makevp_l.txt, and pcregexp.pas.
1586 6. A Windows user reported a minor discrepancy with test 2, which turned out
1587 to be caused by a trailing space on an input line that had got lost in his
1588 copy. The trailing space was an accident, so I've just removed it.
1590 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
1591 that is needed.
1593 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
1594 as "const" (a) because they are and (b) because it helps the PHP
1595 maintainers who have recently made a script to detect big data structures
1596 in the php code that should be moved to the .rodata section. I remembered
1597 to update Builducptable as well, so it won't revert if ucptable.h is ever
1598 re-created.
1600 9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
1601 pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
1602 order to be able to cut out the UTF-8 tables in the latter when UTF-8
1603 support is not required. This saves 1.5-2K of code, which is important in
1604 some applications.
1606 Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
1607 so as not to refer to the tables, even though these functions will never be
1608 called when UTF-8 support is disabled. Otherwise there are problems with a
1609 shared library.
1611 10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
1613 (a) It was defining its arguments as char * instead of void *.
1615 (b) It was assuming that all moves were upwards in memory; this was true
1616 a long time ago when I wrote it, but is no longer the case.
1618 The emulated memove() is provided for those environments that have neither
1619 memmove() nor bcopy(). I didn't think anyone used it these days, but that
1620 is clearly not the case, as these two bugs were recently reported.
1622 11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
1623 and Detrail to create the HTML documentation, the .txt form of the man
1624 pages, and it removes trailing spaces from listed files. It also creates
1625 pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
1626 case, it wraps all the #defines with #ifndefs. This script should be run
1627 before "make dist".
1629 12. Fixed two fairly obscure bugs concerned with quantified caseless matching
1630 with Unicode property support.
1632 (a) For a maximizing quantifier, if the two different cases of the
1633 character were of different lengths in their UTF-8 codings (there are
1634 some cases like this - I found 11), and the matching function had to
1635 back up over a mixture of the two cases, it incorrectly assumed they
1636 were both the same length.
1638 (b) When PCRE was configured to use the heap rather than the stack for
1639 recursion during matching, it was not correctly preserving the data for
1640 the other case of a UTF-8 character when checking ahead for a match
1641 while processing a minimizing repeat. If the check also involved
1642 matching a wide character, but failed, corruption could cause an
1643 erroneous result when trying to check for a repeat of the original
1644 character.
1646 13. Some tidying changes to the testing mechanism:
1648 (a) The RunTest script now detects the internal link size and whether there
1649 is UTF-8 and UCP support by running ./pcretest -C instead of relying on
1650 values substituted by "configure". (The RunGrepTest script already did
1651 this for UTF-8.) The configure.ac script no longer substitutes the
1652 relevant variables.
1654 (b) The debugging options /B and /D in pcretest show the compiled bytecode
1655 with length and offset values. This means that the output is different
1656 for different internal link sizes. Test 2 is skipped for link sizes
1657 other than 2 because of this, bypassing the problem. Unfortunately,
1658 there was also a test in test 3 (the locale tests) that used /B and
1659 failed for link sizes other than 2. Rather than cut the whole test out,
1660 I have added a new /Z option to pcretest that replaces the length and
1661 offset values with spaces. This is now used to make test 3 independent
1662 of link size. (Test 2 will be tidied up later.)
1664 14. If erroroffset was passed as NULL to pcre_compile, it provoked a
1665 segmentation fault instead of returning the appropriate error message.
1667 15. In multiline mode when the newline sequence was set to "any", the pattern
1668 ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
1669 This doesn't seem right; it now treats the CRLF combination as the line
1670 ending, and so does not match in that case. It's only a pattern such as ^$
1671 that would hit this one: something like ^ABC$ would have failed after \r
1672 and then tried again after \r\n.
1674 16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
1675 in an attempt to make files that differ only in their line terminators
1676 compare equal. This works on Linux.
1678 17. Under certain error circumstances pcregrep might try to free random memory
1679 as it exited. This is now fixed, thanks to valgrind.
1681 19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
1682 "abc\r\n\r\n", it found an unwanted second match after the second \r. This
1683 was because its rules for how to advance for /g after matching an empty
1684 string at the end of a line did not allow for this case. They now check for
1685 it specially.
1687 20. pcretest is supposed to handle patterns and data of any length, by
1688 extending its buffers when necessary. It was getting this wrong when the
1689 buffer for a data line had to be extended.
1691 21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
1692 CRLF as a newline sequence.
1694 22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
1695 out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
1696 I have nevertheless tidied it up.
1698 23. Added some casts to kill warnings from HP-UX ia64 compiler.
1700 24. Added a man page for pcre-config.
1703 Version 7.0 19-Dec-06
1704 ---------------------
1706 1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
1707 moving to gcc 4.1.1.
1709 2. The -S option for pcretest uses setrlimit(); I had omitted to #include
1710 sys/time.h, which is documented as needed for this function. It doesn't
1711 seem to matter on Linux, but it showed up on some releases of OS X.
1713 3. It seems that there are systems where bytes whose values are greater than
1714 127 match isprint() in the "C" locale. The "C" locale should be the
1715 default when a C program starts up. In most systems, only ASCII printing
1716 characters match isprint(). This difference caused the output from pcretest
1717 to vary, making some of the tests fail. I have changed pcretest so that:
1719 (a) When it is outputting text in the compiled version of a pattern, bytes
1720 other than 32-126 are always shown as hex escapes.
1722 (b) When it is outputting text that is a matched part of a subject string,
1723 it does the same, unless a different locale has been set for the match
1724 (using the /L modifier). In this case, it uses isprint() to decide.
1726 4. Fixed a major bug that caused incorrect computation of the amount of memory
1727 required for a compiled pattern when options that changed within the
1728 pattern affected the logic of the preliminary scan that determines the
1729 length. The relevant options are -x, and -i in UTF-8 mode. The result was
1730 that the computed length was too small. The symptoms of this bug were
1731 either the PCRE error "internal error: code overflow" from pcre_compile(),
1732 or a glibc crash with a message such as "pcretest: free(): invalid next
1733 size (fast)". Examples of patterns that provoked this bug (shown in
1734 pcretest format) are:
1736 /(?-x: )/x
1737 /(?x)(?-x: \s*#\s*)/
1738 /((?i)[\x{c0}])/8
1739 /(?i:[\x{c0}])/8
1741 HOWEVER: Change 17 below makes this fix obsolete as the memory computation
1742 is now done differently.
1744 5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
1745 wrapper classes; (b) implement a new function in the C++ scanner that is
1746 more efficient than the old way of doing things because it avoids levels of
1747 recursion in the regex matching; (c) add a paragraph to the documentation
1748 for the FullMatch() function.
1750 6. The escape sequence \n was being treated as whatever was defined as
1751 "newline". Not only was this contrary to the documentation, which states
1752 that \n is character 10 (hex 0A), but it also went horribly wrong when
1753 "newline" was defined as CRLF. This has been fixed.
1755 7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
1756 was being set to -1 for the "end of line" case (supposedly a value that no
1757 character can have). Though this value is never used (the check for end of
1758 line is "zero bytes in current character"), it caused compiler complaints.
1759 I've changed it to 0xffffffff.
1761 8. In pcre_version.c, the version string was being built by a sequence of
1762 C macros that, in the event of PCRE_PRERELEASE being defined as an empty
1763 string (as it is for production releases) called a macro with an empty
1764 argument. The C standard says the result of this is undefined. The gcc
1765 compiler treats it as an empty string (which was what was wanted) but it is
1766 reported that Visual C gives an error. The source has been hacked around to
1767 avoid this problem.
1769 9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
1770 builds of pcretest, and changed the call to _setmode() to use _O_BINARY
1771 instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
1772 of them did).
1774 10. Originally, pcretest opened its input and output without "b"; then I was
1775 told that "b" was needed in some environments, so it was added for release
1776 5.0 to both the input and output. (It makes no difference on Unix-like
1777 systems.) Later I was told that it is wrong for the input on Windows. I've
1778 now abstracted the modes into two macros, to make it easier to fiddle with
1779 them, and removed "b" from the input mode under Windows.
1781 11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
1783 12. Added -help and --help to pcretest as an official way of being reminded
1784 of the options.
1786 13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
1787 and pcrecpp.cc because they annoy compilers at high warning levels.
1789 14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
1791 15. Fixed an occurrence of == in configure.ac that should have been = (shell
1792 scripts are not C programs :-) and which was not noticed because it works
1793 on Linux.
1795 16. pcretest is supposed to handle any length of pattern and data line (as one
1796 line or as a continued sequence of lines) by extending its input buffer if
1797 necessary. This feature was broken for very long pattern lines, leading to
1798 a string of junk being passed to pcre_compile() if the pattern was longer
1799 than about 50K.
1801 17. I have done a major re-factoring of the way pcre_compile() computes the
1802 amount of memory needed for a compiled pattern. Previously, there was code
1803 that made a preliminary scan of the pattern in order to do this. That was
1804 OK when PCRE was new, but as the facilities have expanded, it has become
1805 harder and harder to keep it in step with the real compile phase, and there
1806 have been a number of bugs (see for example, 4 above). I have now found a
1807 cunning way of running the real compile function in a "fake" mode that
1808 enables it to compute how much memory it would need, while actually only
1809 ever using a few hundred bytes of working memory and without too many
1810 tests of the mode. This should make future maintenance and development
1811 easier. A side effect of this work is that the limit of 200 on the nesting
1812 depth of parentheses has been removed (though this was never a serious
1813 limitation, I suspect). However, there is a downside: pcre_compile() now
1814 runs more slowly than before (30% or more, depending on the pattern). I
1815 hope this isn't a big issue. There is no effect on runtime performance.
1817 18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
1818 newline (only possible for the last line of a file) and it was a
1819 pattern that set a locale (followed by /Lsomething), pcretest crashed.
1821 19. Added additional timing features to pcretest. (1) The -tm option now times
1822 matching only, not compiling. (2) Both -t and -tm can be followed, as a
1823 separate command line item, by a number that specifies the number of
1824 repeats to use when timing. The default is 50000; this gives better
1825 precision, but takes uncomfortably long for very large patterns.
1827 20. Extended pcre_study() to be more clever in cases where a branch of a
1828 subpattern has no definite first character. For example, (a*|b*)[cd] would
1829 previously give no result from pcre_study(). Now it recognizes that the
1830 first character must be a, b, c, or d.
1832 21. There was an incorrect error "recursive call could loop indefinitely" if
1833 a subpattern (or the entire pattern) that was being tested for matching an
1834 empty string contained only one non-empty item after a nested subpattern.
1835 For example, the pattern (?>\x{100}*)\d(?R) provoked this error
1836 incorrectly, because the \d was being skipped in the check.
1838 22. The pcretest program now has a new pattern option /B and a command line
1839 option -b, which is equivalent to adding /B to every pattern. This causes
1840 it to show the compiled bytecode, without the additional information that
1841 -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
1842 is the same as /B/I).
1844 23. A new optimization is now able automatically to treat some sequences such
1845 as a*b as a*+b. More specifically, if something simple (such as a character
1846 or a simple class like \d) has an unlimited quantifier, and is followed by
1847 something that cannot possibly match the quantified thing, the quantifier
1848 is automatically "possessified".
1850 24. A recursive reference to a subpattern whose number was greater than 39
1851 went wrong under certain circumstances in UTF-8 mode. This bug could also
1852 have affected the operation of pcre_study().
1854 25. Realized that a little bit of performance could be had by replacing
1855 (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
1857 26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
1859 27. Possessive quantifiers such as a++ were previously implemented by turning
1860 them into atomic groups such as ($>a+). Now they have their own opcodes,
1861 which improves performance. This includes the automatically created ones
1862 from 23 above.
1864 28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
1865 lookahead was broken if it was not anchored. PCRE was mistakenly expecting
1866 the first matched character to be a colon. This applied both to named and
1867 numbered groups.
1869 29. The ucpinternal.h header file was missing its idempotency #ifdef.
1871 30. I was sent a "project" file called libpcre.a.dev which I understand makes
1872 building PCRE on Windows easier, so I have included it in the distribution.
1874 31. There is now a check in pcretest against a ridiculously large number being
1875 returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
1876 loop, the loop is abandoned.
1878 32. Forward references to subpatterns in conditions such as (?(2)...) where
1879 subpattern 2 is defined later cause pcre_compile() to search forwards in
1880 the pattern for the relevant set of parentheses. This search went wrong
1881 when there were unescaped parentheses in a character class, parentheses
1882 escaped with \Q...\E, or parentheses in a #-comment in /x mode.
1884 33. "Subroutine" calls and backreferences were previously restricted to
1885 referencing subpatterns earlier in the regex. This restriction has now
1886 been removed.
1888 34. Added a number of extra features that are going to be in Perl 5.10. On the
1889 whole, these are just syntactic alternatives for features that PCRE had
1890 previously implemented using the Python syntax or my own invention. The
1891 other formats are all retained for compatibility.
1893 (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
1894 as (?P<name>...). The new forms, as well as being in Perl 5.10, are
1895 also .NET compatible.
1897 (b) A recursion or subroutine call to a named group can now be defined as
1898 (?&name) as well as (?P>name).
1900 (c) A backreference to a named group can now be defined as \k<name> or
1901 \k'name' as well as (?P=name). The new forms, as well as being in Perl
1902 5.10, are also .NET compatible.
1904 (d) A conditional reference to a named group can now use the syntax
1905 (?(<name>) or (?('name') as well as (?(name).
1907 (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
1908 groups (named and numbered) that are never evaluated inline, but can be
1909 called as "subroutines" from elsewhere. In effect, the DEFINE condition
1910 is always false. There may be only one alternative in such a group.
1912 (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
1913 as the simple (?(R). The condition is true only if the most recent
1914 recursion is that of the given number or name. It does not search out
1915 through the entire recursion stack.
1917 (g) The escape \gN or \g{N} has been added, where N is a positive or
1918 negative number, specifying an absolute or relative reference.
1920 35. Tidied to get rid of some further signed/unsigned compiler warnings and
1921 some "unreachable code" warnings.
1923 36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
1924 things, this adds five new scripts.
1926 37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
1927 There were also incompatibilities regarding the handling of \Q..\E inside
1928 character classes, for example with patterns like [\Qa\E-\Qz\E] where the
1929 hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
1931 38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
1932 matches an empty string, and forcibly breaks the loop. There were bugs in
1933 this code in non-simple cases. For a pattern such as ^(a()*)* matched
1934 against aaaa the result was just "a" rather than "aaaa", for example. Two
1935 separate and independent bugs (that affected different cases) have been
1936 fixed.
1938 39. Refactored the code to abolish the use of different opcodes for small
1939 capturing bracket numbers. This is a tidy that I avoided doing when I
1940 removed the limit on the number of capturing brackets for 3.5 back in 2001.
1941 The new approach is not only tidier, it makes it possible to reduce the
1942 memory needed to fix the previous bug (38).
1944 40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
1945 sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
1946 processing dot, circumflex, or dollar metacharacters, or #-comments in /x
1947 mode.
1949 41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
1950 report.
1952 42. Applied patch, originally from Ari Pollak, modified by Google, to allow
1953 copy construction and assignment in the C++ wrapper.
1955 43. Updated pcregrep to support "--newline=any". In the process, I fixed a
1956 couple of bugs that could have given wrong results in the "--newline=crlf"
1957 case.
1959 44. Added a number of casts and did some reorganization of signed/unsigned int
1960 variables following suggestions from Dair Grant. Also renamed the variable
1961 "this" as "item" because it is a C++ keyword.
1963 45. Arranged for dftables to add
1965 #include "pcre_internal.h"
1967 to pcre_chartables.c because without it, gcc 4.x may remove the array
1968 definition from the final binary if PCRE is built into a static library and
1969 dead code stripping is activated.
1971 46. For an unanchored pattern, if a match attempt fails at the start of a
1972 newline sequence, and the newline setting is CRLF or ANY, and the next two
1973 characters are CRLF, advance by two characters instead of one.
1976 Version 6.7 04-Jul-06
1977 ---------------------
1979 1. In order to handle tests when input lines are enormously long, pcretest has
1980 been re-factored so that it automatically extends its buffers when
1981 necessary. The code is crude, but this _is_ just a test program. The
1982 default size has been increased from 32K to 50K.
1984 2. The code in pcre_study() was using the value of the re argument before
1985 testing it for NULL. (Of course, in any sensible call of the function, it
1986 won't be NULL.)
1988 3. The memmove() emulation function in pcre_internal.h, which is used on
1989 systems that lack both memmove() and bcopy() - that is, hardly ever -
1990 was missing a "static" storage class specifier.
1992 4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
1993 containing an extended class (one that cannot be represented by a bitmap
1994 because it contains high-valued characters or Unicode property items, e.g.
1995 [\pZ]). Almost always one would set UTF-8 mode when processing such a
1996 pattern, but PCRE should not loop if you do not (it no longer does).
1997 [Detail: two cases were found: (a) a repeated subpattern containing an
1998 extended class; (b) a recursive reference to a subpattern that followed a
1999 previous extended class. It wasn't skipping over the extended class
2000 correctly when UTF-8 mode was not set.]
2002 5. A negated single-character class was not being recognized as fixed-length
2003 in lookbehind assertions such as (?<=[^f]), leading to an incorrect
2004 compile error "lookbehind assertion is not fixed length".
2006 6. The RunPerlTest auxiliary script was showing an unexpected difference
2007 between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
2008 write a Perl script that can interpret lines of an input file either as
2009 byte characters or as UTF-8, which is what "perltest" was being required to
2010 do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
2011 can't do is switch easily at run time between having the "use utf8;" pragma
2012 or not. In the end, I fudged it by using the RunPerlTest script to insert
2013 "use utf8;" explicitly for the UTF-8 tests.
2015 7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
2016 the end of the subject string, contrary to the documentation and to what
2017 Perl does. This was true of both matching functions. Now it matches only at
2018 the start of the subject and immediately after *internal* newlines.
2020 8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
2021 a pointer to an int instead of a pointer to an unsigned long int. This
2022 caused problems on 64-bit systems.
2024 9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
2025 instance of the 'standard' template library not being so standard".
2027 10. There was no check on the number of named subpatterns nor the maximum
2028 length of a subpattern name. The product of these values is used to compute
2029 the size of the memory block for a compiled pattern. By supplying a very
2030 long subpattern name and a large number of named subpatterns, the size
2031 computation could be caused to overflow. This is now prevented by limiting
2032 the length of names to 32 characters, and the number of named subpatterns
2033 to 10,000.
2035 11. Subpatterns that are repeated with specific counts have to be replicated in
2036 the compiled pattern. The size of memory for this was computed from the
2037 length of the subpattern and the repeat count. The latter is limited to
2038 65535, but there was no limit on the former, meaning that integer overflow
2039 could in principle occur. The compiled length of a repeated subpattern is
2040 now limited to 30,000 bytes in order to prevent this.
2042 12. Added the optional facility to have named substrings with the same name.
2044 13. Added the ability to use a named substring as a condition, using the
2045 Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
2046 are numbers (not recommended). Forward references are permitted.
2048 14. Added forward references in named backreferences (if you see what I mean).
2050 15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
2051 pattern could run off the end of the subject. For example, the pattern
2052 "(?s)(.{1,5})"8 did this with the subject "ab".
2054 16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
2055 PCRE_CASELESS was set when matching characters that were quantified with ?
2056 or *.
2058 17. A character class other than a single negated character that had a minimum
2059 but no maximum quantifier - for example [ab]{6,} - was not handled
2060 correctly by pce_dfa_exec(). It would match only one character.
2062 18. A valid (though odd) pattern that looked like a POSIX character
2063 class but used an invalid character after [ (for example [[,abc,]]) caused
2064 pcre_compile() to give the error "Failed: internal error: code overflow" or
2065 in some cases to crash with a glibc free() error. This could even happen if
2066 the pattern terminated after [[ but there just happened to be a sequence of
2067 letters, a binary zero, and a closing ] in the memory that followed.
2069 19. Perl's treatment of octal escapes in the range \400 to \777 has changed
2070 over the years. Originally (before any Unicode support), just the bottom 8
2071 bits were taken. Thus, for example, \500 really meant \100. Nowadays the
2072 output from "man perlunicode" includes this:
2074 The regular expression compiler produces polymorphic opcodes. That
2075 is, the pattern adapts to the data and automatically switches to
2076 the Unicode character scheme when presented with Unicode data--or
2077 instead uses a traditional byte scheme when presented with byte
2078 data.
2080 Sadly, a wide octal escape does not cause a switch, and in a string with
2081 no other multibyte characters, these octal escapes are treated as before.
2082 Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern
2083 /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
2084 Unicode string.
2086 I have not perpetrated such confusion in PCRE. Up till now, it took just
2087 the bottom 8 bits, as in old Perl. I have now made octal escapes with
2088 values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
2089 translate to the appropriate multibyte character.
2091 29. Applied some refactoring to reduce the number of warnings from Microsoft
2092 and Borland compilers. This has included removing the fudge introduced
2093 seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
2094 a warning about an unused variable.
2096 21. PCRE has not included VT (character 0x0b) in the set of whitespace
2097 characters since release 4.0, because Perl (from release 5.004) does not.
2098 [Or at least, is documented not to: some releases seem to be in conflict
2099 with the documentation.] However, when a pattern was studied with
2100 pcre_study() and all its branches started with \s, PCRE still included VT
2101 as a possible starting character. Of course, this did no harm; it just
2102 caused an unnecessary match attempt.
2104 22. Removed a now-redundant internal flag bit that recorded the fact that case
2105 dependency changed within the pattern. This was once needed for "required
2106 byte" processing, but is no longer used. This recovers a now-scarce options
2107 bit. Also moved the least significant internal flag bit to the most-
2108 significant bit of the word, which was not previously used (hangover from
2109 the days when it was an int rather than a uint) to free up another bit for
2110 the future.
2112 23. Added support for CRLF line endings as well as CR and LF. As well as the
2113 default being selectable at build time, it can now be changed at runtime
2114 via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
2115 specify that it is scanning data with non-default line endings.
2117 24. Changed the definition of CXXLINK to make it agree with the definition of
2118 LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
2120 25. Applied Ian Taylor's patches to avoid using another stack frame for tail
2121 recursions. This makes a big different to stack usage for some patterns.
2123 26. If a subpattern containing a named recursion or subroutine reference such
2124 as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
2125 the space required for the compiled pattern went wrong and gave too small a
2126 value. Depending on the environment, this could lead to "Failed: internal
2127 error: code overflow at offset 49" or "glibc detected double free or
2128 corruption" errors.
2130 27. Applied patches from Google (a) to support the new newline modes and (b) to
2131 advance over multibyte UTF-8 characters in GlobalReplace.
2133 28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
2134 difference for some implementation of PCRE in some Windows version.
2136 29. Added some extra testing facilities to pcretest:
2138 \q<number> in a data line sets the "match limit" value
2139 \Q<number> in a data line sets the "match recursion limt" value
2140 -S <number> sets the stack size, where <number> is in megabytes
2142 The -S option isn't available for Windows.
2145 Version 6.6 06-Feb-06
2146 ---------------------
2148 1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
2149 in pcreposix.h. I have copied the definition from pcre.h.
2151 2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
2152 because pcre.h is no longer a built file.
2154 3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
2155 not normally included in the compiled code.
2158 Version 6.5 01-Feb-06
2159 ---------------------
2161 1. When using the partial match feature with pcre_dfa_exec(), it was not
2162 anchoring the second and subsequent partial matches at the new starting
2163 point. This could lead to incorrect results. For example, with the pattern
2164 /1234/, partially matching against "123" and then "a4" gave a match.
2166 2. Changes to pcregrep:
2168 (a) All non-match returns from pcre_exec() were being treated as failures
2169 to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
2170 error message is output. Some extra information is given for the
2172 probably the only errors that are likely to be caused by users (by
2173 specifying a regex that has nested indefinite repeats, for instance).
2174 If there are more than 20 of these errors, pcregrep is abandoned.
2176 (b) A binary zero was treated as data while matching, but terminated the
2177 output line if it was written out. This has been fixed: binary zeroes
2178 are now no different to any other data bytes.
2180 (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
2181 used to set a locale for matching. The --locale=xxxx long option has
2182 been added (no short equivalent) to specify a locale explicitly on the
2183 pcregrep command, overriding the environment variables.
2185 (d) When -B was used with -n, some line numbers in the output were one less
2186 than they should have been.
2188 (e) Added the -o (--only-matching) option.
2190 (f) If -A or -C was used with -c (count only), some lines of context were
2191 accidentally printed for the final match.
2193 (g) Added the -H (--with-filename) option.
2195 (h) The combination of options -rh failed to suppress file names for files
2196 that were found from directory arguments.
2198 (i) Added the -D (--devices) and -d (--directories) options.
2200 (j) Added the -F (--fixed-strings) option.
2202 (k) Allow "-" to be used as a file name for -f as well as for a data file.
2204 (l) Added the --colo(u)r option.
2206 (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
2207 is not present by default.
2209 3. A nasty bug was discovered in the handling of recursive patterns, that is,
2210 items such as (?R) or (?1), when the recursion could match a number of
2211 alternatives. If it matched one of the alternatives, but subsequently,
2212 outside the recursion, there was a failure, the code tried to back up into
2213 the recursion. However, because of the way PCRE is implemented, this is not
2214 possible, and the result was an incorrect result from the match.
2216 In order to prevent this happening, the specification of recursion has
2217 been changed so that all such subpatterns are automatically treated as
2218 atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
2220 4. I had overlooked the fact that, in some locales, there are characters for
2221 which isalpha() is true but neither isupper() nor islower() are true. In
2222 the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
2223 and ordfeminine) are like this. This affected the treatment of \w and \W
2224 when they appeared in character classes, but not when they appeared outside
2225 a character class. The bit map for "word" characters is now created
2226 separately from the results of isalnum() instead of just taking it from the
2227 upper, lower, and digit maps. (Plus the underscore character, of course.)
2229 5. The above bug also affected the handling of POSIX character classes such as
2230 [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
2231 permanent tables. Instead, the bit maps for such a class were previously
2232 created as the appropriate unions of the upper, lower, and digit bitmaps.
2233 Now they are created by subtraction from the [[:word:]] class, which has
2234 its own bitmap.
2236 6. The [[:blank:]] character class matches horizontal, but not vertical space.
2237 It is created by subtracting the vertical space characters (\x09, \x0a,
2238 \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
2239 subtraction was done in the overall bitmap for a character class, meaning
2240 that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
2241 be recognized. This bug has been fixed.
2243 7. Patches from the folks at Google:
2245 (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
2246 real life, but is still worth protecting against".
2248 (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
2249 regular expressions".
2251 (c) pcre_scanner.cc: avoid use of std::count() because not all systems
2252 have it.
2254 (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
2255 "configure" and the latter not, in order to fix a problem somebody had
2256 with compiling the Arg class on HP-UX.
2258 (e) Improve the error-handling of the C++ wrapper a little bit.
2260 (f) New tests for checking recursion limiting.
2262 8. The pcre_memmove() function, which is used only if the environment does not
2263 have a standard memmove() function (and is therefore rarely compiled),
2264 contained two bugs: (a) use of int instead of size_t, and (b) it was not
2265 returning a result (though PCRE never actually uses the result).
2267 9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
2268 large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
2269 returned instead of calling malloc() with an overflowing number that would
2270 most likely cause subsequent chaos.
2272 10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
2274 11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
2275 with this option is matched, the nmatch and pmatch options of regexec() are
2276 ignored.
2278 12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
2279 provided in case anyone wants to the the POSIX interface with UTF-8
2280 strings.
2282 13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
2283 C++ linking (needed for some HP-UX environments).
2285 14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
2286 (unused parameter) and in the pcre_printint() function (omitted "default"
2287 switch label when the default is to do nothing).
2289 15. Added some code to make it possible, when PCRE is compiled as a C++
2290 library, to replace subject pointers for pcre_exec() with a smart pointer
2291 class, thus making it possible to process discontinuous strings.
2293 16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
2294 much the same function. They were added by different people who were trying
2295 to make PCRE easy to compile on non-Unix systems. It has been suggested
2296 that PCRE_EXPORT be abolished now that there is more automatic apparatus
2297 for compiling on Windows systems. I have therefore replaced it with
2298 PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
2299 defaults to "extern" for C or "extern C" for C++, which works fine on
2300 Unix-like systems. It is now possible to override the value of PCRE_DATA_
2301 SCOPE with something explicit in config.h. In addition:
2303 (a) pcreposix.h still had just "extern" instead of either of these macros;
2304 I have replaced it with PCRE_DATA_SCOPE.
2306 (b) Functions such as _pcre_xclass(), which are internal to the library,
2307 but external in the C sense, all had PCRE_EXPORT in their definitions.
2308 This is apparently wrong for the Windows case, so I have removed it.
2309 (It makes no difference on Unix-like systems.)
2311 17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
2312 of recursive calls to match(). This is different to MATCH_LIMIT because
2313 that limits the total number of calls to match(), not all of which increase
2314 the depth of recursion. Limiting the recursion depth limits the amount of
2315 stack (or heap if NO_RECURSE is set) that is used. The default can be set
2316 when PCRE is compiled, and changed at run time. A patch from Google adds
2317 this functionality to the C++ interface.
2319 18. Changes to the handling of Unicode character properties:
2321 (a) Updated the table to Unicode 4.1.0.
2323 (b) Recognize characters that are not in the table as "Cn" (undefined).
2325 (c) I revised the way the table is implemented to a much improved format
2326 which includes recognition of ranges. It now supports the ranges that
2327 are defined in UnicodeData.txt, and it also amalgamates other
2328 characters into ranges. This has reduced the number of entries in the
2329 table from around 16,000 to around 3,000, thus reducing its size
2330 considerably. I realized I did not need to use a tree structure after
2331 all - a binary chop search is just as efficient. Having reduced the
2332 number of entries, I extended their size from 6 bytes to 8 bytes to
2333 allow for more data.
2335 (d) Added support for Unicode script names via properties such as \p{Han}.
2337 19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
2338 matching that character.
2340 20. When matching a repeated Unicode property with a minimum greater than zero,
2341 (for example \pL{2,}), PCRE could look past the end of the subject if it
2342 reached it while seeking the minimum number of characters. This could
2343 happen only if some of the characters were more than one byte long, because
2344 there is a check for at least the minimum number of bytes.
2346 21. Refactored the implementation of \p and \P so as to be more general, to
2347 allow for more different types of property in future. This has changed the
2348 compiled form incompatibly. Anybody with saved compiled patterns that use
2349 \p or \P will have to recompile them.
2351 22. Added "Any" and "L&" to the supported property types.
2353 23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
2354 but give a compile time error if the value is greater than 0xff.
2356 24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
2357 accidentally not being installed or uninstalled.
2359 25. The pcre.h file was built from pcre.h.in, but the only changes that were
2360 made were to insert the current release number. This seemed silly, because
2361 it made things harder for people building PCRE on systems that don't run
2362 "configure". I have turned pcre.h into a distributed file, no longer built
2363 by "configure", with the version identification directly included. There is
2364 no longer a pcre.h.in file.
2366 However, this change necessitated a change to the pcre-config script as
2367 well. It is built from pcre-config.in, and one of the substitutions was the
2368 release number. I have updated configure.ac so that ./configure now finds
2369 the release number by grepping pcre.h.
2371 26. Added the ability to run the tests under valgrind.
2374 Version 6.4 05-Sep-05
2375 ---------------------
2377 1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
2378 "--" to be printed when multiple files were scanned, even when none of the
2379 -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
2380 consider it to be a bug, and have restored the previous behaviour.
2382 2. A couple of code tidies to get rid of compiler warnings.
2384 3. The pcretest program used to cheat by referring to symbols in the library
2385 whose names begin with _pcre_. These are internal symbols that are not
2386 really supposed to be visible externally, and in some environments it is
2387 possible to suppress them. The cheating is now confined to including
2388 certain files from the library's source, which is a bit cleaner.
2390 4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
2391 file's purpose clearer.
2393 5. Reorganized pcre_ucp_findchar().
2396 Version 6.3 15-Aug-05
2397 ---------------------
2399 1. The file libpcre.pc.in did not have general read permission in the tarball.
2401 2. There were some problems when building without C++ support:
2403 (a) If C++ support was not built, "make install" and "make test" still
2404 tried to test it.
2406 (b) There were problems when the value of CXX was explicitly set. Some
2407 changes have been made to try to fix these, and ...
2409 (c) --disable-cpp can now be used to explicitly disable C++ support.
2411 (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
2412 backslash in a target when C++ was disabled. This confuses some
2413 versions of "make", apparently. Using an intermediate variable solves
2414 this. (Same for CPP_LOBJ.)
2416 3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
2417 (non-Windows) now includes $(CFLAGS) because these flags are sometimes
2418 necessary on certain architectures.
2420 4. Added a setting of -export-symbols-regex to the link command to remove
2421 those symbols that are exported in the C sense, but actually are local
2422 within the library, and not documented. Their names all begin with
2423 "_pcre_". This is not a perfect job, because (a) we have to except some
2424 symbols that pcretest ("illegally") uses, and (b) the facility isn't always
2425 available (and never for static libraries). I have made a note to try to
2426 find a way round (a) in the future.
2429 Version 6.2 01-Aug-05
2430 ---------------------
2432 1. There was no test for integer overflow of quantifier values. A construction
2433 such as {1111111111111111} would give undefined results. What is worse, if
2434 a minimum quantifier for a parenthesized subpattern overflowed and became
2435 negative, the calculation of the memory size went wrong. This could have
2436 led to memory overwriting.
2438 2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
2440 3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
2441 operating environments where this matters.
2443 4. Applied Giuseppe Maxia's patch to add additional features for controlling
2444 PCRE options from within the C++ wrapper.
2446 5. Named capturing subpatterns were not being correctly counted when a pattern
2447 was compiled. This caused two problems: (a) If there were more than 100
2448 such subpatterns, the calculation of the memory needed for the whole
2449 compiled pattern went wrong, leading to an overflow error. (b) Numerical
2450 back references of the form \12, where the number was greater than 9, were
2451 not recognized as back references, even though there were sufficient
2452 previous subpatterns.
2454 6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
2455 versions of gcc, e.g. 2.95.4.
2458 Version 6.1 21-Jun-05
2459 ---------------------
2461 1. There was one reference to the variable "posix" in pcretest.c that was not
2462 surrounded by "#if !defined NOPOSIX".
2464 2. Make it possible to compile pcretest without DFA support, UTF8 support, or
2465 the cross-check on the old pcre_info() function, for the benefit of the
2466 cut-down version of PCRE that is currently imported into Exim.
2468 3. A (silly) pattern starting with (?i)(?-i) caused an internal space
2469 allocation error. I've done the easy fix, which wastes 2 bytes for sensible
2470 patterns that start (?i) but I don't think that matters. The use of (?i) is
2471 just an example; this all applies to the other options as well.
2473 4. Since libtool seems to echo the compile commands it is issuing, the output
2474 from "make" can be reduced a bit by putting "@" in front of each libtool
2475 compile command.
2477 5. Patch from the folks at Google for configure.in to be a bit more thorough
2478 in checking for a suitable C++ installation before trying to compile the
2479 C++ stuff. This should fix a reported problem when a compiler was present,
2480 but no suitable headers.
2482 6. The man pages all had just "PCRE" as their title. I have changed them to
2483 be the relevant file name. I have also arranged that these names are
2484 retained in the file doc/pcre.txt, which is a concatenation in text format
2485 of all the man pages except the little individual ones for each function.
2487 7. The NON-UNIX-USE file had not been updated for the different set of source
2488 files that come with release 6. I also added a few comments about the C++
2489 wrapper.
2492 Version 6.0 07-Jun-05
2493 ---------------------
2495 1. Some minor internal re-organization to help with my DFA experiments.
2497 2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
2498 didn't matter for the library itself when fully configured, but did matter
2499 when compiling without UCP support, or within Exim, where the ucp files are
2500 not imported.
2502 3. Refactoring of the library code to split up the various functions into
2503 different source modules. The addition of the new DFA matching code (see
2504 below) to a single monolithic source would have made it really too
2505 unwieldy, quite apart from causing all the code to be include in a
2506 statically linked application, when only some functions are used. This is
2507 relevant even without the DFA addition now that patterns can be compiled in
2508 one application and matched in another.
2510 The downside of splitting up is that there have to be some external
2511 functions and data tables that are used internally in different modules of
2512 the library but which are not part of the API. These have all had their
2513 names changed to start with "_pcre_" so that they are unlikely to clash
2514 with other external names.
2516 4. Added an alternate matching function, pcre_dfa_exec(), which matches using
2517 a different (DFA) algorithm. Although it is slower than the original
2518 function, it does have some advantages for certain types of matching
2519 problem.
2521 5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
2522 including restarting after a partial match.
2524 6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
2525 defined when compiling for Windows was sent to me. I have put it into the
2526 code, though I have no means of testing or verifying it.
2528 7. Added the pcre_refcount() auxiliary function.
2530 8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
2531 match before or at the first newline in the subject string. In pcretest,
2532 the /f option on a pattern can be used to set this.
2534 9. A repeated \w when used in UTF-8 mode with characters greater than 256
2535 would behave wrongly. This has been present in PCRE since release 4.0.
2537 10. A number of changes to the pcregrep command:
2539 (a) Refactored how -x works; insert ^(...)$ instead of setting
2540 PCRE_ANCHORED and checking the length, in preparation for adding
2541 something similar for -w.
2543 (b) Added the -w (match as a word) option.
2545 (c) Refactored the way lines are read and buffered so as to have more
2546 than one at a time available.
2548 (d) Implemented a pcregrep test script.
2550 (e) Added the -M (multiline match) option. This allows patterns to match
2551 over several lines of the subject. The buffering ensures that at least
2552 8K, or the rest of the document (whichever is the shorter) is available
2553 for matching (and similarly the previous 8K for lookbehind assertions).
2555 (f) Changed the --help output so that it now says
2557 -w, --word-regex(p)
2559 instead of two lines, one with "regex" and the other with "regexp"
2560 because that confused at least one person since the short forms are the
2561 same. (This required a bit of code, as the output is generated
2562 automatically from a table. It wasn't just a text change.)
2564 (g) -- can be used to terminate pcregrep options if the next thing isn't an
2565 option but starts with a hyphen. Could be a pattern or a path name
2566 starting with a hyphen, for instance.
2568 (h) "-" can be given as a file name to represent stdin.
2570 (i) When file names are being printed, "(standard input)" is used for
2571 the standard input, for compatibility with GNU grep. Previously
2572 "<stdin>" was used.
2574 (j) The option --label=xxx can be used to supply a name to be used for
2575 stdin when file names are being printed. There is no short form.
2577 (k) Re-factored the options decoding logic because we are going to add
2578 two more options that take data. Such options can now be given in four
2579 different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
2581 (l) Added the -A, -B, and -C options for requesting that lines of context
2582 around matches be printed.
2584 (m) Added the -L option to print the names of files that do not contain
2585 any matching lines, that is, the complement of -l.
2587 (n) The return code is 2 if any file cannot be opened, but pcregrep does
2588 continue to scan other files.
2590 (o) The -s option was incorrectly implemented. For compatibility with other
2591 greps, it now suppresses the error message for a non-existent or non-
2592 accessible file (but not the return code). There is a new option called
2593 -q that suppresses the output of matching lines, which was what -s was
2594 previously doing.
2596 (p) Added --include and --exclude options to specify files for inclusion
2597 and exclusion when recursing.
2599 11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
2600 Hopefully, it now does.
2602 12. Missing cast in pcre_study().
2604 13. Added an "uninstall" target to the makefile.
2606 14. Replaced "extern" in the function prototypes in Makefile.in with
2607 "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
2608 world, but is set differently for Windows.
2610 15. Added a second compiling function called pcre_compile2(). The only
2611 difference is that it has an extra argument, which is a pointer to an
2612 integer error code. When there is a compile-time failure, this is set
2613 non-zero, in addition to the error test pointer being set to point to an
2614 error message. The new argument may be NULL if no error number is required
2615 (but then you may as well call pcre_compile(), which is now just a
2616 wrapper). This facility is provided because some applications need a
2617 numeric error indication, but it has also enabled me to tidy up the way
2618 compile-time errors are handled in the POSIX wrapper.
2620 16. Added VPATH=.libs to the makefile; this should help when building with one
2621 prefix path and installing with another. (Or so I'm told by someone who
2622 knows more about this stuff than I do.)
2624 17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
2625 passes PCRE_DOTALL to the pcre_compile() function, making the "." character
2626 match everything, including newlines. This is not POSIX-compatible, but
2627 somebody wanted the feature. From pcretest it can be activated by using
2628 both the P and the s flags.
2630 18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
2632 19. libpcre.pc was being incorrectly installed as executable.
2634 20. A couple of places in pcretest check for end-of-line by looking for '\n';
2635 it now also looks for '\r' so that it will work unmodified on Windows.
2637 21. Added Google's contributed C++ wrapper to the distribution.
2639 22. Added some untidy missing memory free() calls in pcretest, to keep
2640 Electric Fence happy when testing.
2644 Version 5.0 13-Sep-04
2645 ---------------------
2647 1. Internal change: literal characters are no longer packed up into items
2648 containing multiple characters in a single byte-string. Each character
2649 is now matched using a separate opcode. However, there may be more than one
2650 byte in the character in UTF-8 mode.
2652 2. The pcre_callout_block structure has two new fields: pattern_position and
2653 next_item_length. These contain the offset in the pattern to the next match
2654 item, and its length, respectively.
2656 3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
2657 insertion of callouts before each pattern item. Added the /C option to
2658 pcretest to make use of this.
2660 4. On the advice of a Windows user, the lines
2662 #if defined(_WIN32) || defined(WIN32)
2663 _setmode( _fileno( stdout ), 0x8000 );
2664 #endif /* defined(_WIN32) || defined(WIN32) */
2666 have been added to the source of pcretest. This apparently does useful
2667 magic in relation to line terminators.
2669 5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
2670 for the benefit of those environments where the "b" makes a difference.
2672 6. The icc compiler has the same options as gcc, but "configure" doesn't seem
2673 to know about it. I have put a hack into configure.in that adds in code
2674 to set GCC=yes if CC=icc. This seems to end up at a point in the
2675 generated configure script that is early enough to affect the setting of
2676 compiler options, which is what is needed, but I have no means of testing
2677 whether it really works. (The user who reported this had patched the
2678 generated configure script, which of course I cannot do.)
2680 LATER: After change 22 below (new libtool files), the configure script
2681 seems to know about icc (and also ecc). Therefore, I have commented out
2682 this hack in configure.in.
2684 7. Added support for pkg-config (2 patches were sent in).
2686 8. Negated POSIX character classes that used a combination of internal tables
2687 were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
2688 [[:^ascii]]. Typically, they would match almost any characters. The other
2689 POSIX classes were not broken in this way.
2691 9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
2692 to find the match, as PCRE was deluded into thinking that the match had to
2693 start at the start point or following a newline. The same bug applied to
2694 patterns with negative forward assertions or any backward assertions
2695 preceding ".*" at the start, unless the pattern required a fixed first
2696 character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
2698 10. In UTF-8 mode, when moving forwards in the subject after a failed match
2699 starting at the last subject character, bytes beyond the end of the subject
2700 string were read.
2702 11. Renamed the variable "class" as "classbits" to make life easier for C++
2703 users. (Previously there was a macro definition, but it apparently wasn't
2704 enough.)
2706 12. Added the new field "tables" to the extra data so that tables can be passed
2707 in at exec time, or the internal tables can be re-selected. This allows
2708 a compiled regex to be saved and re-used at a later time by a different
2709 program that might have everything at different addresses.
2711 13. Modified the pcre-config script so that, when run on Solaris, it shows a
2712 -R library as well as a -L library.
2714 14. The debugging options of pcretest (-d on the command line or D on a
2715 pattern) showed incorrect output for anything following an extended class
2716 that contained multibyte characters and which was followed by a quantifier.
2718 15. Added optional support for general category Unicode character properties
2719 via the \p, \P, and \X escapes. Unicode property support implies UTF-8
2720 support. It adds about 90K to the size of the library. The meanings of the
2721 inbuilt class escapes such as \d and \s have NOT been changed.
2723 16. Updated pcredemo.c to include calls to free() to release the memory for the
2724 compiled pattern.
2726 17. The generated file chartables.c was being created in the source directory
2727 instead of in the building directory. This caused the build to fail if the
2728 source directory was different from the building directory, and was
2729 read-only.
2731 18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
2732 file. No doubt somebody will tell me if they don't make sense... Also added
2733 Dan Mooney's comments about building on OpenVMS.
2735 19. Added support for partial matching via the PCRE_PARTIAL option for
2736 pcre_exec() and the \P data escape in pcretest.
2738 20. Extended pcretest with 3 new pattern features:
2740 (i) A pattern option of the form ">rest-of-line" causes pcretest to
2741 write the compiled pattern to the file whose name is "rest-of-line".
2742 This is a straight binary dump of the data, with the saved pointer to
2743 the character tables forced to be NULL. The study data, if any, is
2744 written too. After writing, pcretest reads a new pattern.
2746 (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
2747 compiled pattern from the given file. There must not be any
2748 occurrences of "<" in the file name (pretty unlikely); if there are,
2749 pcretest will instead treat the initial "<" as a pattern delimiter.
2750 After reading in the pattern, pcretest goes on to read data lines as
2751 usual.
2753 (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
2754 and 16-bit fields in a compiled pattern, to simulate a pattern that
2755 was compiled on a host of opposite endianness.
2757 21. The pcre-exec() function can now cope with patterns that were compiled on
2758 hosts of opposite endianness, with this restriction:
2760 As for any compiled expression that is saved and used later, the tables
2761 pointer field cannot be preserved; the extra_data field in the arguments
2762 to pcre_exec() should be used to pass in a tables address if a value
2763 other than the default internal tables were used at compile time.
2765 22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
2766 now diagnosed as an error. Previously, most of the time, a negative number
2767 would have been treated as zero, but if in addition "ovector" was passed as
2768 NULL, a crash could occur.
2770 23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
2771 new versions from the libtool 1.5 distribution (the last one is a copy of
2772 a file called libtool.m4). This seems to have fixed the need to patch
2773 "configure" to support Darwin 1.3 (which I used to do). However, I still
2774 had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
2775 workstation).
2777 24. Changed the PCRE licence to be the more standard "BSD" licence.
2780 Version 4.5 01-Dec-03
2781 ---------------------
2783 1. There has been some re-arrangement of the code for the match() function so
2784 that it can be compiled in a version that does not call itself recursively.
2785 Instead, it keeps those local variables that need separate instances for
2786 each "recursion" in a frame on the heap, and gets/frees frames whenever it
2787 needs to "recurse". Keeping track of where control must go is done by means
2788 of setjmp/longjmp. The whole thing is implemented by a set of macros that
2789 hide most of the details from the main code, and operates only if
2790 NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
2791 "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
2792 operating.
2794 To make it easier for callers to provide specially tailored get/free
2795 functions for this usage, two new functions, pcre_stack_malloc, and
2796 pcre_stack_free, are used. They are always called in strict stacking order,
2797 and the size of block requested is always the same.
2799 The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
2800 PCRE has been compiled to use the stack or the heap for recursion. The
2801 -C option of pcretest uses this to show which version is compiled.
2803 A new data escape \S, is added to pcretest; it causes the amounts of store
2804 obtained and freed by both kinds of malloc/free at match time to be added
2805 to the output.
2807 2. Changed the locale test to use "fr_FR" instead of "fr" because that's
2808 what's available on my current Linux desktop machine.
2810 3. When matching a UTF-8 string, the test for a valid string at the start has
2811 been extended. If start_offset is not zero, PCRE now checks that it points
2812 to a byte that is the start of a UTF-8 character. If not, it returns
2813 PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
2814 this is necessary because there may be backward assertions in the pattern.
2815 When matching the same subject several times, it may save resources to use
2816 PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
2818 4. The code for checking the validity of UTF-8 strings has been tightened so
2819 that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
2820 containing "overlong sequences".
2822 5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
2823 I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
2824 should have been "&", but it just so happened that all the cases this let
2825 through by mistake were picked up later in the function.
2827 6. I had used a variable called "isblank" - this is a C99 function, causing
2828 some compilers to warn. To avoid this, I renamed it (as "blankclass").
2830 7. Cosmetic: (a) only output another newline at the end of pcretest if it is
2831 prompting; (b) run "./pcretest /dev/null" at the start of the test script
2832 so the version is shown; (c) stop "make test" echoing "./RunTest".
2834 8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
2836 9. The prototype for memmove() for systems that don't have it was using
2837 size_t, but the inclusion of the header that defines size_t was later. I've
2838 moved the #includes for the C headers earlier to avoid this.
2840 10. Added some adjustments to the code to make it easier to compiler on certain
2841 special systems:
2843 (a) Some "const" qualifiers were missing.
2844 (b) Added the macro EXPORT before all exported functions; by default this
2845 is defined to be empty.
2846 (c) Changed the dftables auxiliary program (that builds chartables.c) so
2847 that it reads its output file name as an argument instead of writing
2848 to the standard output and assuming this can be redirected.
2850 11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
2851 class containing characters with values greater than 255, PCRE compilation
2852 went into a loop.
2854 12. A recursive reference to a subpattern that was within another subpattern
2855 that had a minimum quantifier of zero caused PCRE to crash. For example,
2856 (x(y(?2))z)? provoked this bug with a subject that got as far as the
2857 recursion. If the recursively-called subpattern itself had a zero repeat,
2858 that was OK.
2860 13. In pcretest, the buffer for reading a data line was set at 30K, but the
2861 buffer into which it was copied (for escape processing) was still set at
2862 1024, so long lines caused crashes.
2864 14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
2865 "internal error: code overflow...". This applied to any character class
2866 that was followed by a possessive quantifier.
2868 15. Modified the Makefile to add libpcre.la as a prerequisite for
2869 libpcreposix.la because I was told this is needed for a parallel build to
2870 work.
2872 16. If a pattern that contained .* following optional items at the start was
2873 studied, the wrong optimizing data was generated, leading to matching
2874 errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
2875 matching string must start with a or b or c. The correct conclusion for
2876 this pattern is that a match can start with any character.
2879 Version 4.4 13-Aug-03
2880 ---------------------
2882 1. In UTF-8 mode, a character class containing characters with values between
2883 127 and 255 was not handled correctly if the compiled pattern was studied.
2884 In fixing this, I have also improved the studying algorithm for such
2885 classes (slightly).
2887 2. Three internal functions had redundant arguments passed to them. Removal
2888 might give a very teeny performance improvement.
2890 3. Documentation bug: the value of the capture_top field in a callout is *one
2891 more than* the number of the hightest numbered captured substring.
2893 4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
2894 in incorrectly linking with a previously installed version. They now link
2895 explicitly with libpcre.la.
2897 5. configure.in no longer needs to recognize Cygwin specially.
2899 6. A problem in pcre.in for Windows platforms is fixed.
2901 7. If a pattern was successfully studied, and the -d (or /D) flag was given to
2902 pcretest, it used to include the size of the study block as part of its
2903 output. Unfortunately, the structure contains a field that has a different
2904 size on different hardware architectures. This meant that the tests that
2905 showed this size failed. As the block is currently always of a fixed size,
2906 this information isn't actually particularly useful in pcretest output, so
2907 I have just removed it.
2909 8. Three pre-processor statements accidentally did not start in column 1.
2910 Sadly, there are *still* compilers around that complain, even though
2911 standard C has not required this for well over a decade. Sigh.
2913 9. In pcretest, the code for checking callouts passed small integers in the
2914 callout_data field, which is a void * field. However, some picky compilers
2915 complained about the casts involved for this on 64-bit systems. Now
2916 pcretest passes the address of the small integer instead, which should get
2917 rid of the warnings.
2919 10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
2920 both compile and run time, and gives an error if an invalid UTF-8 sequence
2921 is found. There is a option for disabling this check in cases where the
2922 string is known to be correct and/or the maximum performance is wanted.
2924 11. In response to a bug report, I changed one line in Makefile.in from
2926 -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
2927 to
2928 -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
2930 to look similar to other lines, but I have no way of telling whether this
2931 is the right thing to do, as I do not use Windows. No doubt I'll get told
2932 if it's wrong...
2935 Version 4.3 21-May-03
2936 ---------------------
2938 1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
2939 Makefile.
2941 2. Some refactoring to improve the quality of the code:
2943 (i) The utf8_table... variables are now declared "const".
2945 (ii) The code for \cx, which used the "case flipping" table to upper case
2946 lower case letters, now just substracts 32. This is ASCII-specific,
2947 but the whole concept of \cx is ASCII-specific, so it seems
2948 reasonable.
2950 (iii) PCRE was using its character types table to recognize decimal and
2951 hexadecimal digits in the pattern. This is silly, because it handles
2952 only 0-9, a-f, and A-F, but the character types table is locale-
2953 specific, which means strange things might happen. A private
2954 table is now used for this - though it costs 256 bytes, a table is
2955 much faster than multiple explicit tests. Of course, the standard
2956 character types table is still used for matching digits in subject
2957 strings against \d.
2959 (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
2960 ending in _t are). So I've renamed it as ESC_tee.
2962 3. The first argument for regexec() in the POSIX wrapper should have been
2963 defined as "const".
2965 4. Changed pcretest to use malloc() for its buffers so that they can be
2966 Electric Fenced for debugging.
2968 5. There were several places in the code where, in UTF-8 mode, PCRE would try
2969 to read one or more bytes before the start of the subject string. Often this
2970 had no effect on PCRE's behaviour, but in some circumstances it could
2971 provoke a segmentation fault.
2973 6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
2974 to try to read one or more bytes before the start of the subject string.
2976 7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
2977 UTF-8 support could misbehave in various ways if the subject string
2978 contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
2979 area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
2980 back over UTF-8 characters.)
2983 Version 4.2 14-Apr-03
2984 ---------------------
2986 1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
2988 2. Changes to the building process, supplied by Ronald Landheer-Cieslak
2989 [ON_WINDOWS]: new variable, "#" on non-Windows platforms
2990 [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
2991 [WIN_PREFIX]: new variable, "cyg" for Cygwin
2992 * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
2994 Note: automatic setting of the BUILD variables is not yet working
2995 set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
2996 compile-time but not at link-time
2997 [LINK]: use for linking executables only
2998 make different versions for Windows and non-Windows
2999 [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
3000 libraries
3001 [LINK_FOR_BUILD]: new variable
3002 [OBJEXT]: use throughout
3003 [EXEEXT]: use throughout
3004 <winshared>: new target
3005 <wininstall>: new target
3006 <dftables.o>: use native compiler
3007 <dftables>: use native linker
3008 <install>: handle Windows platform correctly
3009 <clean>: ditto
3010 <check>: ditto
3011 copy DLL to top builddir before testing
3013 As part of these changes, -no-undefined was removed again. This was reported
3014 to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
3015 in any case.
3017 3. Some tidies to get rid of compiler warnings:
3019 . In the match_data structure, match_limit was an unsigned long int, whereas
3020 match_call_count was an int. I've made them both unsigned long ints.
3022 . In pcretest the fact that a const uschar * doesn't automatically cast to
3023 a void * provoked a warning.
3025 . Turning on some more compiler warnings threw up some "shadow" variables
3026 and a few more missing casts.
3028 4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
3029 option, a class that contained a single character with a value between 128
3030 and 255 (e.g. /[\xFF]/) caused PCRE to crash.
3032 5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
3033 option, a class that contained several characters, but with at least one
3034 whose value was between 128 and 255 caused PCRE to crash.
3037 Version 4.1 12-Mar-03
3038 ---------------------
3040 1. Compiling with gcc -pedantic found a couple of places where casts were
3041 needed, and a string in dftables.c that was longer than standard compilers are
3042 required to support.
3044 2. Compiling with Sun's compiler found a few more places where the code could
3045 be tidied up in order to avoid warnings.
3047 3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
3048 first of these names is deprecated in the latest Autoconf in favour of the name
3049 CC_FOR_BUILD, because "host" is typically used to mean the system on which the
3050 compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
3051 analogy I have changed it to CFLAGS_FOR_BUILD.
3053 4. Added -no-undefined to the linking command in the Makefile, because this is
3054 apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
3055 linking step for the pcreposix library.
3057 5. PCRE was failing to diagnose the case of two named groups with the same
3058 name.
3060 6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
3061 literal character that is needed in the subject for a match, and scans along to
3062 ensure that it is present before embarking on the full matching process. This
3063 saves time in cases of nested unlimited repeats that are never going to match.
3064 Problem: the scan can take a lot of time if the subject is very long (e.g.
3065 megabytes), thus penalizing straightforward matches. It is now done only if the
3066 amount of subject to be scanned is less than 1000 bytes.
3068 7. A lesser problem with the same optimization is that it was recording the
3069 first character of an anchored pattern as "needed", thus provoking a search
3070 right along the subject, even when the first match of the pattern was going to
3071 fail. The "needed" character is now not set for anchored patterns, unless it
3072 follows something in the pattern that is of non-fixed length. Thus, it still
3073 fulfils its original purpose of finding quick non-matches in cases of nested
3074 unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
3077 Version 4.0 17-Feb-03
3078 ---------------------
3080 1. If a comment in an extended regex that started immediately after a meta-item
3081 extended to the end of string, PCRE compiled incorrect data. This could lead to
3082 all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
3084 2. Moved to autoconf 2.53 and libtool 1.4.2.
3086 3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
3087 the special perltest8 script is no longer needed - all the tests can be run
3088 from a single perltest script.
3090 4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
3091 by \s. It has now been removed in PCRE. This means it isn't recognized as
3092 whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
3093 class [:space:] *does* include VT, thereby creating a mess.
3095 5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
3096 space and tab.
3098 6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
3099 its new features into the main test script, reducing the number of scripts.
3101 7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
3102 were backward compatible, and made the (?i) apply to the whole pattern, as if
3103 /i were given. Now it behaves more logically, and applies the option setting
3104 only to what follows. PCRE has been changed to follow suit. However, if it
3105 finds options settings right at the start of the pattern, it extracts them into
3106 the global options, as before. Thus, they show up in the info data.
3108 8. Added support for the \Q...\E escape sequence. Characters in between are
3109 treated as literals. This is slightly different from Perl in that $ and @ are
3110 also handled as literals inside the quotes. In Perl, they will cause variable
3111 interpolation. Note the following examples:
3113 Pattern PCRE matches Perl matches
3115 \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
3116 \Qabc\$xyz\E abc\$xyz abc\$xyz
3117 \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
3119 For compatibility with Perl, \Q...\E sequences are recognized inside character
3120 classes as well as outside them.
3122 9. Re-organized 3 code statements in pcretest to avoid "overflow in
3123 floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
3124 (size_t) cast to one statement in pcretest and one in pcreposix to avoid
3125 signed/unsigned warnings.
3127 10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
3128 option for pcretest, so I've replaced it by a simple function that does just
3129 that job.
3131 11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
3132 "pcregrep -".
3134 12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
3135 Java package. This provides some syntactic sugar for simple cases of what my
3136 documentation calls "once-only subpatterns". A pattern such as x*+ is the same
3137 as (?>x*). In other words, if what is inside (?>...) is just a single repeated
3138 item, you can use this simplified notation. Note that only makes sense with
3139 greedy quantifiers. Consequently, the use of the possessive quantifier forces
3140 greediness, whatever the setting of the PCRE_UNGREEDY option.
3142 13. A change of greediness default within a pattern was not taking effect at
3143 the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
3144 subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
3145 was abstracted outside.
3147 14. PCRE now supports the \G assertion. It is true when the current matching
3148 position is at the start point of the match. This differs from \A when the
3149 starting offset is non-zero. Used with the /g option of pcretest (or similar
3150 code), it works in the same way as it does for Perl's /g option. If all
3151 alternatives of a regex begin with \G, the expression is anchored to the start
3152 match position, and the "anchored" flag is set in the compiled expression.
3154 15. Some bugs concerning the handling of certain option changes within patterns
3155 have been fixed. These applied to options other than (?ims). For example,
3156 "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
3157 been the other way round. Some of this was related to change 7 above.
3159 16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
3160 features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
3161 and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
3162 POSIX classes only within a class (e.g. /[[:alpha:]]/).
3164 17. Added support for Perl's \C escape. This matches one byte, even in UTF8
3165 mode. Unlike ".", it always matches newline, whatever the setting of
3166 PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
3167 assertions. Perl allows it, but it doesn't (in general) work because it can't
3168 calculate the length of the lookbehind. At least, that's the case for Perl
3169 5.8.0 - I've been told they are going to document that it doesn't work in
3170 future.
3172 18. Added an error diagnosis for escapes that PCRE does not support: these are
3173 \L, \l, \N, \P, \p, \U, \u, and \X.
3175 19. Although correctly diagnosing a missing ']' in a character class, PCRE was
3176 reading past the end of the pattern in cases such as /[abcd/.
3178 20. PCRE was getting more memory than necessary for patterns with classes that
3179 contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
3181 21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
3182 compiling PCRE for use with Virtual Pascal.
3184 22. Small fix to the Makefile to make it work properly if the build is done
3185 outside the source tree.
3187 23. Added a new extension: a condition to go with recursion. If a conditional
3188 subpattern starts with (?(R) the "true" branch is used if recursion has
3189 happened, whereas the "false" branch is used only at the top level.
3191 24. When there was a very long string of literal characters (over 255 bytes
3192 without UTF support, over 250 bytes with UTF support), the computation of how
3193 much memory was required could be incorrect, leading to segfaults or other
3194 strange effects.
3196 25. PCRE was incorrectly assuming anchoring (either to start of subject or to
3197 start of line for a non-DOTALL pattern) when a pattern started with (.*) and
3198 there was a subsequent back reference to those brackets. This meant that, for
3199 example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
3200 possible to check for precisely this case. All we can do is abandon the
3201 optimization if .* occurs inside capturing brackets when there are any back
3202 references whatsoever. (See below for a better fix that came later.)
3204 26. The handling of the optimization for finding the first character of a
3205 non-anchored pattern, and for finding a character that is required later in the
3206 match were failing in some cases. This didn't break the matching; it just
3207 failed to optimize when it could. The way this is done has been re-implemented.
3209 27. Fixed typo in error message for invalid (?R item (it said "(?p").
3211 28. Added a new feature that provides some of the functionality that Perl
3212 provides with (?{...}). The facility is termed a "callout". The way it is done
3213 in PCRE is for the caller to provide an optional function, by setting
3214 pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
3215 global variable. By default it is unset, which disables all calling out. To get
3216 the function called, the regex must include (?C) at appropriate points. This
3217 is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
3218 This provides a means of identifying different callout points. When PCRE
3219 reaches such a point in the regex, if pcre_callout has been set, the external
3220 function is called. It is provided with data in a structure called
3221 pcre_callout_block, which is defined in pcre.h. If the function returns 0,
3222 matching continues; if it returns a non-zero value, the match at the current
3223 point fails. However, backtracking will occur if possible. [This was changed
3224 later and other features added - see item 49 below.]
3226 29. pcretest is upgraded to test the callout functionality. It provides a
3227 callout function that displays information. By default, it shows the start of
3228 the match and the current position in the text. There are some new data escapes
3229 to vary what happens:
3231 \C+ in addition, show current contents of captured substrings
3232 \C- do not supply a callout function
3233 \C!n return 1 when callout number n is reached
3234 \C!n!m return 1 when callout number n is reached for the mth time
3236 30. If pcregrep was called with the -l option and just a single file name, it
3237 output "<stdin>" if a match was found, instead of the file name.
3239 31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
3240 slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
3241 pcre_exec(). This saves a malloc/free per call. The default value of
3242 POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
3243 when configuring.
3245 32. The default maximum size of a compiled pattern is 64K. There have been a
3246 few cases of people hitting this limit. The code now uses macros to handle the
3247 storing of links as offsets within the compiled pattern. It defaults to 2-byte
3248 links, but this can be changed to 3 or 4 bytes by --with-link-size when
3249 configuring. Tests 2 and 5 work only with 2-byte links because they output
3250 debugging information about compiled patterns.
3252 33. Internal code re-arrangements:
3254 (a) Moved the debugging function for printing out a compiled regex into
3255 its own source file (printint.c) and used #include to pull it into
3256 pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
3257 separate copies.
3259 (b) Defined the list of op-code names for debugging as a macro in
3260 internal.h so that it is next to the definition of the opcodes.
3262 (c) Defined a table of op-code lengths for simpler skipping along compiled
3263 code. This is again a macro in internal.h so that it is next to the
3264 definition of the opcodes.
3266 34. Added support for recursive calls to individual subpatterns, along the
3267 lines of Robin Houston's patch (but implemented somewhat differently).
3269 35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
3270 allow it to read and process whole directories in Win32. This code was
3271 contributed by Lionel Fourquaux; it has not been tested by me.
3273 36. Added support for named subpatterns. The Python syntax (?P<name>...) is
3274 used to name a group. Names consist of alphanumerics and underscores, and must
3275 be unique. Back references use the syntax (?P=name) and recursive calls use
3276 (?P>name) which is a PCRE extension to the Python extension. Groups still have
3277 numbers. The function pcre_fullinfo() can be used after compilation to extract
3278 a name/number map. There are three relevant calls:
3280 PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
3281 PCRE_INFO_NAMECOUNT yields the number of entries
3282 PCRE_INFO_NAMETABLE yields a pointer to the map.
3284 The map is a vector of fixed-size entries. The size of each entry depends on
3285 the length of the longest name used. The first two bytes of each entry are the
3286 group number, most significant byte first. There follows the corresponding
3287 name, zero terminated. The names are in alphabetical order.
3289 37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
3290 case instead of 255. Making it the same both with and without UTF-8 support
3291 means that the same test output works with both.
3293 38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
3294 calling malloc() with a zero argument.
3296 39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
3297 optimization. I've improved things by keeping a bitmap of backreferences with
3298 numbers 1-31 so that if .* occurs inside capturing brackets that are not in
3299 fact referenced, the optimization can be applied. It is unlikely that a
3300 relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
3301 the match to follow \n) will appear inside brackets with a number greater than
3302 31, but if it does, any back reference > 31 suppresses the optimization.
3304 40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
3305 of disabling numbered capturing parentheses. Any opening parenthesis that is
3306 not followed by ? behaves as if it were followed by ?: but named parentheses
3307 can still be used for capturing (and they will acquire numbers in the usual
3308 way).
3310 41. Redesigned the return codes from the match() function into yes/no/error so
3311 that errors can be passed back from deep inside the nested calls. A malloc
3312 failure while inside a recursive subpattern call now causes the
3313 PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
3315 42. It is now possible to set a limit on the number of times the match()
3316 function is called in a call to pcre_exec(). This facility makes it possible to
3317 limit the amount of recursion and backtracking, though not in a directly
3318 obvious way, because the match() function is used in a number of different
3319 circumstances. The count starts from zero for each position in the subject
3320 string (for non-anchored patterns). The default limit is, for compatibility, a
3321 large number, namely 10 000 000. You can change this in two ways:
3323 (a) When configuring PCRE before making, you can use --with-match-limit=n
3324 to set a default value for the compiled library.
3326 (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
3327 a different value is set. See 45 below.
3329 If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
3331 43. Added a new function pcre_config(int, void *) to enable run-time extraction
3332 of things that can be changed at compile time. The first argument specifies
3333 what is wanted and the second points to where the information is to be placed.
3334 The current list of available information is:
3338 The output is an integer that is set to one if UTF-8 support is available;
3339 otherwise it is set to zero.
3343 The output is an integer that it set to the value of the code that is used for
3344 newline. It is either LF (10) or CR (13).
3348 The output is an integer that contains the number of bytes used for internal
3349 linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
3353 The output is an integer that contains the threshold above which the POSIX
3354 interface uses malloc() for output vectors. See item 31 above.
3358 The output is an unsigned integer that contains the default limit of the number
3359 of match() calls in a pcre_exec() execution. See 42 above.
3361 44. pcretest has been upgraded by the addition of the -C option. This causes it
3362 to extract all the available output from the new pcre_config() function, and to
3363 output it. The program then exits immediately.
3365 45. A need has arisen to pass over additional data with calls to pcre_exec() in
3366 order to support additional features. One way would have been to define
3367 pcre_exec2() (for example) with extra arguments, but this would not have been
3368 extensible, and would also have required all calls to the original function to
3369 be mapped to the new one. Instead, I have chosen to extend the mechanism that
3370 is used for passing in "extra" data from pcre_study().
3372 The pcre_extra structure is now exposed and defined in pcre.h. It currently
3373 contains the following fields:
3375 flags a bitmap indicating which of the following fields are set
3376 study_data opaque data from pcre_study()
3377 match_limit a way of specifying a limit on match() calls for a specific
3378 call to pcre_exec()
3379 callout_data data for callouts (see 49 below)
3381 The flag bits are also defined in pcre.h, and are
3387 The pcre_study() function now returns one of these new pcre_extra blocks, with
3388 the actual study data pointed to by the study_data field, and the
3389 PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
3390 before. That is, this change is entirely upwards-compatible and requires no
3391 change to existing code.
3393 If you want to pass in additional data to pcre_exec(), you can either place it
3394 in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
3395 block.
3397 46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
3398 data string contains the escape sequence \M, pcretest calls pcre_exec() several
3399 times with different match limits, until it finds the minimum value needed for
3400 pcre_exec() to complete. The value is then output. This can be instructive; for
3401 most simple matches the number is quite small, but for pathological cases it
3402 gets very large very quickly.
3404 47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
3405 returns the size of the data block pointed to by the study_data field in a
3406 pcre_extra block, that is, the value that was passed as the argument to
3407 pcre_malloc() when PCRE was getting memory in which to place the information
3408 created by pcre_study(). The fourth argument should point to a size_t variable.
3409 pcretest has been extended so that this information is shown after a successful
3410 pcre_study() call when information about the compiled regex is being displayed.
3412 48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
3413 because what follows is always an absolute path. (Later: it turns out that this
3414 is more than cosmetic for MinGW, because it doesn't like empty path
3415 components.)
3417 49. Some changes have been made to the callout feature (see 28 above):
3419 (i) A callout function now has three choices for what it returns:
3421 0 => success, carry on matching
3422 > 0 => failure at this point, but backtrack if possible
3423 < 0 => serious error, return this value from pcre_exec()
3425 Negative values should normally be chosen from the set of PCRE_ERROR_xxx
3426 values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
3427 "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
3428 use by callout functions. It will never be used by PCRE itself.
3430 (ii) The pcre_extra structure (see 45 above) has a void * field called
3431 callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
3432 pcre_callout_block structure has a field of the same name. The contents of
3433 the field passed in the pcre_extra structure are passed to the callout
3434 function in the corresponding field in the callout block. This makes it
3435 easier to use the same callout-containing regex from multiple threads. For
3436 testing, the pcretest program has a new data escape
3438 \C*n pass the number n (may be negative) as callout_data
3440 If the callout function in pcretest receives a non-zero value as
3441 callout_data, it returns that value.
3443 50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
3444 there were some redundant $(CFLAGS) in commands that are now specified as
3445 $(LINK), which already includes $(CFLAGS).
3447 51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
3448 has been compiled with UTF-8 support *and* pcre_compile() has been compiled
3449 with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
3450 one-byte characters throughout. Note that case-insensitive matching applies
3451 only to characters whose values are less than 256. PCRE doesn't support the
3452 notion of cases for higher-valued characters.
3454 (i) A character class whose characters are all within 0-255 is handled as
3455 a bit map, and the map is inverted for negative classes. Previously, a
3456 character > 255 always failed to match such a class; however it should
3457 match if the class was a negative one (e.g. [^ab]). This has been fixed.
3459 (ii) A negated character class with a single character < 255 is coded as
3460 "not this character" (OP_NOT). This wasn't working properly when the test
3461 character was multibyte, either singly or repeated.
3463 (iii) Repeats of multibyte characters are now handled correctly in UTF-8
3464 mode, for example: \x{100}{2,3}.
3466 (iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
3467 singly or repeated) now correctly test multibyte characters. However,
3468 PCRE doesn't recognize any characters with values greater than 255 as
3469 digits, spaces, or word characters. Such characters always match \D, \S,
3470 and \W, and never match \d, \s, or \w.
3472 (v) Classes may now contain characters and character ranges with values
3473 greater than 255. For example: [ab\x{100}-\x{400}].
3475 (vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
3476 PCRE in UTF-8 mode.
3478 52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
3479 PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
3480 retained for backwards compatibility. (Note that LASTLITERAL is also a byte
3481 value.)
3483 53. The single man page has become too large. I have therefore split it up into
3484 a number of separate man pages. These also give rise to individual HTML pages;
3485 these are now put in a separate directory, and there is an index.html page that
3486 lists them all. Some hyperlinking between the pages has been installed.
3488 54. Added convenience functions for handling named capturing parentheses.
3490 55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
3491 aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
3492 true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
3493 are faulted.
3495 56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
3496 calling configure. These values are used when compiling the dftables.c program
3497 which is run to generate the source of the default character tables. They
3498 default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
3499 you will need to set these values.
3501 57. Updated the building process for Windows DLL, as provided by Fred Cox.
3504 Version 3.9 02-Jan-02
3505 ---------------------
3507 1. A bit of extraneous text had somehow crept into the pcregrep documentation.
3509 2. If --disable-static was given, the building process failed when trying to
3510 build pcretest and pcregrep. (For some reason it was using libtool to compile
3511 them, which is not right, as they aren't part of the library.)
3514 Version 3.8 18-Dec-01
3515 ---------------------
3517 1. The experimental UTF-8 code was completely screwed up. It was packing the
3518 bytes in the wrong order. How dumb can you get?
3521 Version 3.7 29-Oct-01
3522 ---------------------
3524 1. In updating pcretest to check change 1 of version 3.6, I screwed up.
3525 This caused pcretest, when used on the test data, to segfault. Unfortunately,
3526 this didn't happen under Solaris 8, where I normally test things.
3528 2. The Makefile had to be changed to make it work on BSD systems, where 'make'
3529 doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
3530 isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
3531 this fix an hour or so after the initial 3.7 release.)
3534 Version 3.6 23-Oct-01
3535 ---------------------
3537 1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
3538 offsets passed as NULL with zero offset count.
3540 2. The config.guess and config.sub files had not been updated when I moved to
3541 the latest autoconf.
3544 Version 3.5 15-Aug-01
3545 ---------------------
3547 1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
3548 had been forgotten.
3550 2. By using declared but undefined structures, we can avoid using "void"
3551 definitions in pcre.h while keeping the internal definitions of the structures
3552 private.
3554 3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
3555 user point of view, this means that both static and shared libraries are built
3556 by default, but this can be individually controlled. More of the work of
3557 handling this static/shared cases is now inside libtool instead of PCRE's make
3558 file.
3560 4. The pcretest utility is now installed along with pcregrep because it is
3561 useful for users (to test regexs) and by doing this, it automatically gets
3562 relinked by libtool. The documentation has been turned into a man page, so
3563 there are now .1, .txt, and .html versions in /doc.
3565 5. Upgrades to pcregrep:
3566 (i) Added long-form option names like gnu grep.
3567 (ii) Added --help to list all options with an explanatory phrase.
3568 (iii) Added -r, --recursive to recurse into sub-directories.
3569 (iv) Added -f, --file to read patterns from a file.
3571 6. pcre_exec() was referring to its "code" argument before testing that
3572 argument for NULL (and giving an error if it was NULL).
3574 7. Upgraded Makefile.in to allow for compiling in a different directory from
3575 the source directory.
3577 8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
3578 options bits, the pointer it was passed was to an int instead of to an unsigned
3579 long int. This mattered only on 64-bit systems.
3581 9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
3582 generated) instead of pcre.in, which it its source. Also made the same change
3583 in several of the .c files.
3585 10. A new release of gcc defines printf() as a macro, which broke pcretest
3586 because it had an ifdef in the middle of a string argument for printf(). Fixed
3587 by using separate calls to printf().
3589 11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
3590 script, to force use of CR or LF instead of \n in the source. On non-Unix
3591 systems, the value can be set in config.h.
3593 12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
3594 absolute limit. Changed the text of the error message to make this clear, and
3595 likewise updated the man page.
3597 13. The limit of 99 on the number of capturing subpatterns has been removed.
3598 The new limit is 65535, which I hope will not be a "real" limit.
3601 Version 3.4 22-Aug-00
3602 ---------------------
3604 1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
3606 2. Diagnose condition (?(0) as an error instead of crashing on matching.
3609 Version 3.3 01-Aug-00
3610 ---------------------
3612 1. If an octal character was given, but the value was greater than \377, it
3613 was not getting masked to the least significant bits, as documented. This could
3614 lead to crashes in some systems.
3616 2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
3617 the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
3619 3. Added the functions pcre_free_substring() and pcre_free_substring_list().
3620 These just pass their arguments on to (pcre_free)(), but they are provided
3621 because some uses of PCRE bind it to non-C systems that can call its functions,
3622 but cannot call free() or pcre_free() directly.
3624 4. Add "make test" as a synonym for "make check". Corrected some comments in
3625 the Makefile.
3627 5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
3628 Makefile.
3630 6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
3631 command called pgrep for grepping around the active processes.
3633 7. Added the beginnings of support for UTF-8 character strings.
3635 8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
3636 RANLIB to ./ltconfig so that they are used by libtool. I think these are all
3637 the relevant ones. (AR is not passed because ./ltconfig does its own figuring
3638 out for the ar command.)
3641 Version 3.2 12-May-00
3642 ---------------------
3644 This is purely a bug fixing release.
3646 1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
3647 of ZA. This was just one example of several cases that could provoke this bug,
3648 which was introduced by change 9 of version 2.00. The code for breaking
3649 infinite loops after an iteration that matches an empty string was't working
3650 correctly.
3652 2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
3653 when matched against abbab (for example). After matching an empty string, it
3654 wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
3655 caused it to match further down the string than it should.
3657 3. The code contained an inclusion of sys/types.h. It isn't clear why this
3658 was there because it doesn't seem to be needed, and it causes trouble on some
3659 systems, as it is not a Standard C header. It has been removed.
3661 4. Made 4 silly changes to the source to avoid stupid compiler warnings that
3662 were reported on the Macintosh. The changes were from
3664 while ((c = *(++ptr)) != 0 && c != '\n');
3665 to
3666 while ((c = *(++ptr)) != 0 && c != '\n') ;
3668 Totally extraordinary, but if that's what it takes...
3670 5. PCRE is being used in one environment where neither memmove() nor bcopy() is
3671 available. Added HAVE_BCOPY and an autoconf test for it; if neither
3672 HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
3673 assumes the way PCRE uses memmove() (always moving upwards).
3675 6. PCRE is being used in one environment where strchr() is not available. There
3676 was only one use in pcre.c, and writing it out to avoid strchr() probably gives
3677 faster code anyway.
3680 Version 3.1 09-Feb-00
3681 ---------------------
3683 The only change in this release is the fixing of some bugs in Makefile.in for
3684 the "install" target:
3686 (1) It was failing to install pcreposix.h.
3688 (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
3691 Version 3.0 01-Feb-00
3692 ---------------------
3694 1. Add support for the /+ modifier to perltest (to output $` like it does in
3695 pcretest).
3697 2. Add support for the /g modifier to perltest.
3699 3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
3700 matches null strings.
3702 4. Fix perltest so that it doesn't do unwanted things when fed an empty
3703 pattern. Perl treats empty patterns specially - it reuses the most recent
3704 pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
3705 effect.
3707 5. The POSIX interface was broken in that it was just handing over the POSIX
3708 captured string vector to pcre_exec(), but (since release 2.00) PCRE has
3709 required a bigger vector, with some working space on the end. This means that
3710 the POSIX wrapper now has to get and free some memory, and copy the results.
3712 6. Added some simple autoconf support, placing the test data and the
3713 documentation in separate directories, re-organizing some of the
3714 information files, and making it build pcre-config (a GNU standard). Also added
3715 libtool support for building PCRE as a shared library, which is now the
3716 default.
3718 7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
3719 09 are not valid octal constants. Single digits will be used for minor values
3720 less than 10.
3722 8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
3723 existing programs that set these in the POSIX interface can use PCRE without
3724 modification.
3726 9. Added a new function, pcre_fullinfo() with an extensible interface. It can
3727 return all that pcre_info() returns, plus additional data. The pcre_info()
3728 function is retained for compatibility, but is considered to be obsolete.
3730 10. Added experimental recursion feature (?R) to handle one common case that
3731 Perl 5.6 will be able to do with (?p{...}).
3733 11. Added support for POSIX character classes like [:alpha:], which Perl is
3734 adopting.
3737 Version 2.08 31-Aug-99
3738 ----------------------
3740 1. When startoffset was not zero and the pattern began with ".*", PCRE was not
3741 trying to match at the startoffset position, but instead was moving forward to
3742 the next newline as if a previous match had failed.
3744 2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
3745 and could get into a loop if a null string was matched other than at the start
3746 of the subject.
3748 3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
3749 be distinguished at compile time, and for completeness also added PCRE_DATE.
3751 5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
3752 in GnuWin32 environments.
3755 Version 2.07 29-Jul-99
3756 ----------------------
3758 1. The documentation is now supplied in plain text form and HTML as well as in
3759 the form of man page sources.
3761 2. C++ compilers don't like assigning (void *) values to other pointer types.
3762 In particular this affects malloc(). Although there is no problem in Standard
3763 C, I've put in casts to keep C++ compilers happy.
3765 3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
3766 should be (const char *).
3768 4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
3769 be useful for non-Unix systems who don't want to bother with the POSIX stuff.
3770 However, I haven't made this a standard facility. The documentation doesn't
3771 mention it, and the Makefile doesn't support it.
3773 5. The Makefile now contains an "install" target, with editable destinations at
3774 the top of the file. The pcretest program is not installed.
3776 6. pgrep -V now gives the PCRE version number and date.
3778 7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
3779 causing the entire string to be ignored, instead of just the last character.
3781 8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
3782 non-matching string, it can take a very, very long time, even for strings of
3783 quite modest length, because of the nested recursion. PCRE now does better in
3784 some of these cases. It does this by remembering the last required literal
3785 character in the pattern, and pre-searching the subject to ensure it is present
3786 before running the real match. In other words, it applies a heuristic to detect
3787 some types of certain failure quickly, and in the above example, if presented
3788 with a string that has no trailing " it gives "no match" very quickly.
3790 9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
3791 other alternatives are tried instead.
3794 Version 2.06 09-Jun-99
3795 ----------------------
3797 1. Change pcretest's output for amount of store used to show just the code
3798 space, because the remainder (the data block) varies in size between 32-bit and
3799 64-bit systems.
3801 2. Added an extra argument to pcre_exec() to supply an offset in the subject to
3802 start matching at. This allows lookbehinds to work when searching for multiple
3803 occurrences in a string.
3805 3. Added additional options to pcretest for testing multiple occurrences:
3807 /+ outputs the rest of the string that follows a match
3808 /g loops for multiple occurrences, using the new startoffset argument
3809 /G loops for multiple occurrences by passing an incremented pointer
3811 4. PCRE wasn't doing the "first character" optimization for patterns starting
3812 with \b or \B, though it was doing it for other lookbehind assertions. That is,
3813 it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
3814 the letter 'x'. On long subject strings, this gives a significant speed-up.
3817 Version 2.05 21-Apr-99
3818 ----------------------
3820 1. Changed the type of magic_number from int to long int so that it works
3821 properly on 16-bit systems.
3823 2. Fixed a bug which caused patterns starting with .* not to work correctly
3824 when the subject string contained newline characters. PCRE was assuming
3825 anchoring for such patterns in all cases, which is not correct because .* will
3826 not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
3827 DOTALL is set at top level; otherwise it knows that patterns starting with .*
3828 must be retried after every newline in the subject.
3831 Version 2.04 18-Feb-99
3832 ----------------------
3834 1. For parenthesized subpatterns with repeats whose minimum was zero, the
3835 computation of the store needed to hold the pattern was incorrect (too large).
3836 If such patterns were nested a few deep, this could multiply and become a real
3837 problem.
3839 2. Added /M option to pcretest to show the memory requirement of a specific
3840 pattern. Made -m a synonym of -s (which does this globally) for compatibility.
3842 3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
3843 compiled in such a way that the backtracking after subsequent failure was
3844 pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
3845 ((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
3848 Version 2.03 02-Feb-99
3849 ----------------------
3851 1. Fixed typo and small mistake in man page.
3853 2. Added 4th condition (GPL supersedes if conflict) and created separate
3854 LICENCE file containing the conditions.
3856 3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
3857 Perl, that is the internal \ allows the delimiter to be included in the
3858 pattern. Locked out the use of \ as a delimiter. If \ immediately follows
3859 the final delimiter, add \ to the end of the pattern (to test the error).
3861 4. Added the convenience functions for extracting substrings after a successful
3862 match. Updated pcretest to make it able to test these functions.
3865 Version 2.02 14-Jan-99
3866 ----------------------
3868 1. Initialized the working variables associated with each extraction so that
3869 their saving and restoring doesn't refer to uninitialized store.
3871 2. Put dummy code into study.c in order to trick the optimizer of the IBM C
3872 compiler for OS/2 into generating correct code. Apparently IBM isn't going to
3873 fix the problem.
3875 3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
3876 calls, and wasn't printing the correct value for compiling calls. Increased the
3877 default value of LOOPREPEAT, and the number of significant figures in the
3878 times.
3880 4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
3882 5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
3883 a building problem on Windows NT with a FAT file system.
3886 Version 2.01 21-Oct-98
3887 ----------------------
3889 1. Changed the API for pcre_compile() to allow for the provision of a pointer
3890 to character tables built by pcre_maketables() in the current locale. If NULL
3891 is passed, the default tables are used.
3894 Version 2.00 24-Sep-98
3895 ----------------------
3897 1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
3898 it any more.
3900 2. Allow quantification of (?>) groups, and make it work correctly.
3902 3. The first character computation wasn't working for (?>) groups.
3904 4. Correct the implementation of \Z (it is permitted to match on the \n at the
3905 end of the subject) and add 5.005's \z, which really does match only at the
3906 very end of the subject.
3908 5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
3910 6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
3911 DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
3912 localized options. All options to pcre_study() were also removed.
3914 7. Add other new features from 5.005:
3916 $(?<= positive lookbehind
3917 $(?<! negative lookbehind
3918 (?imsx-imsx) added the unsetting capability
3919 such a setting is global if at outer level; local otherwise
3920 (?imsx-imsx:) non-capturing groups with option setting
3921 (?(cond)re|re) conditional pattern matching
3923 A backreference to itself in a repeated group matches the previous
3924 captured string.
3926 8. General tidying up of studying (both automatic and via "study")
3927 consequential on the addition of new assertions.
3929 9. As in 5.005, unlimited repeated groups that could match an empty substring
3930 are no longer faulted at compile time. Instead, the loop is forcibly broken at
3931 runtime if any iteration does actually match an empty substring.
3933 10. Include the RunTest script in the distribution.
3935 11. Added tests from the Perl 5.005_02 distribution. This showed up a few
3936 discrepancies, some of which were old and were also with respect to 5.004. They
3937 have now been fixed.
3940 Version 1.09 28-Apr-98
3941 ----------------------
3943 1. A negated single character class followed by a quantifier with a minimum
3944 value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
3945 program crashes, or just wrong answers. This did not apply to negated classes
3946 containing more than one character, or to minima other than one.
3949 Version 1.08 27-Mar-98
3950 ----------------------
3952 1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
3954 2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
3955 latter must appear before anything that relies on it in the pattern.
3958 Version 1.07 16-Feb-98
3959 ----------------------
3961 1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
3962 repeat of a potentially empty string).
3965 Version 1.06 23-Jan-98
3966 ----------------------
3968 1. Added Markus Oberhumer's little patches for C++.
3970 2. Literal strings longer than 255 characters were broken.
3973 Version 1.05 23-Dec-97
3974 ----------------------
3976 1. Negated character classes containing more than one character were failing if
3977 PCRE_CASELESS was set at run time.
3980 Version 1.04 19-Dec-97
3981 ----------------------
3983 1. Corrected the man page, where some "const" qualifiers had been omitted.
3985 2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
3986 input syntax.
3988 3. Fixed memory leak which occurred when a regex with back references was
3989 matched with an offsets vector that wasn't big enough. The temporary memory
3990 that is used in this case wasn't being freed if the match failed.
3992 4. Tidied pcretest to ensure it frees memory that it gets.
3994 5. Temporary memory was being obtained in the case where the passed offsets
3995 vector was exactly big enough.
3997 6. Corrected definition of offsetof() from change 5 below.
3999 7. I had screwed up change 6 below and broken the rules for the use of
4000 setjmp(). Now fixed.
4003 Version 1.03 18-Dec-97
4004 ----------------------
4006 1. A erroneous regex with a missing opening parenthesis was correctly
4007 diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
4008 on some systems.
4010 2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
4011 it was reported that one broken compiler failed on the former because "code" is
4012 also an independent variable.
4014 3. The erroneous regex a[]b caused an array overrun reference.
4016 4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
4017 fail on data ending with that character. (It was going on too far, and checking
4018 the next character, typically a binary zero.) This was specific to the
4019 optimized code for single-character negative classes.
4021 5. Added a contributed patch from the TIN world which does the following:
4023 + Add an undef for memmove, in case the the system defines a macro for it.
4025 + Add a definition of offsetof(), in case there isn't one. (I don't know
4026 the reason behind this - offsetof() is part of the ANSI standard - but
4027 it does no harm).
4029 + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
4030 most of the places where whitespace preceded '#'. I have given up and
4031 allowed the remaining 2 cases to be at the margin.
4033 + Rename some variables in pcre to eliminate shadowing. This seems very
4034 pedantic, but does no harm, of course.
4036 6. Moved the call to setjmp() into its own function, to get rid of warnings
4037 from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
4039 7. Constructs such as \d{8,} were compiling into the equivalent of
4040 \d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
4041 outcome, but in this particular case used more store than had been allocated,
4042 which caused the bug to be discovered because it threw up an internal error.
4044 8. The debugging code in both pcre and pcretest for outputting the compiled
4045 form of a regex was going wrong in the case of back references followed by
4046 curly-bracketed repeats.
4049 Version 1.02 12-Dec-97
4050 ----------------------
4052 1. Typos in pcre.3 and comments in the source fixed.
4054 2. Applied a contributed patch to get rid of places where it used to remove
4055 'const' from variables, and fixed some signed/unsigned and uninitialized
4056 variable warnings.
4058 3. Added the "runtest" target to Makefile.
4060 4. Set default compiler flag to -O2 rather than just -O.
4063 Version 1.01 19-Nov-97
4064 ----------------------
4066 1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
4067 like /([ab]*)*/, that is, for classes with more than one character in them.
4069 2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
4070 as /((?>a*))*/ (a PCRE_EXTRA facility).
4073 Version 1.00 18-Nov-97
4074 ----------------------
4076 1. Added compile-time macros to support systems such as SunOS4 which don't have
4077 memmove() or strerror() but have other things that can be used instead.
4079 2. Arranged that "make clean" removes the executables.
4082 Version 0.99 27-Oct-97
4083 ----------------------
4085 1. Fixed bug in code for optimizing classes with only one character. It was
4086 initializing a 32-byte map regardless, which could cause it to run off the end
4087 of the memory it had got.
4089 2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
4092 Version 0.98 22-Oct-97
4093 ----------------------
4095 1. Fixed bug in code for handling temporary memory usage when there are more
4096 back references than supplied space in the ovector. This could cause segfaults.
4099 Version 0.97 21-Oct-97
4100 ----------------------
4102 1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
4104 2. Optimized negated single characters not to use a bit map.
4106 3. Brought error texts together as macro definitions; clarified some of them;
4107 fixed one that was wrong - it said "range out of order" when it meant "invalid
4108 escape sequence".
4110 4. Changed some char * arguments to const char *.
4112 5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
4114 6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
4115 pcretest.
4118 Version 0.96 16-Oct-97
4119 ----------------------
4121 1. Added a simple "pgrep" utility to the distribution.
4123 2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
4124 unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
4125 where "ddd" means "one or more decimal digits".
4127 3. Fixed serious bug. If a pattern had a back reference, but the call to
4128 pcre_exec() didn't supply a large enough ovector to record the related
4129 identifying subpattern, the match always failed. PCRE now remembers the number
4130 of the largest back reference, and gets some temporary memory in which to save
4131 the offsets during matching if necessary, in order to ensure that
4132 backreferences always work.
4134 4. Increased the compatibility with Perl in a number of ways:
4136 (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
4137 to request this handling. The option can be set at compile or exec time.
4139 (b) $ matches before a terminating newline by default; an option
4140 PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
4141 mode). The option can be set at compile or exec time.
4143 (c) The handling of \ followed by a digit other than 0 is now supposed to be
4144 the same as Perl's. If the decimal number it represents is less than 10
4145 or there aren't that many previous left capturing parentheses, an octal
4146 escape is read. Inside a character class, it's always an octal escape,
4147 even if it is a single digit.
4149 (d) An escaped but undefined alphabetic character is taken as a literal,
4150 unless PCRE_EXTRA is set. Currently this just reserves the remaining
4151 escapes.
4153 (e) {0} is now permitted. (The previous item is removed from the compiled
4154 pattern).
4156 5. Changed all the names of code files so that the basic parts are no longer
4157 than 10 characters, and abolished the teeny "globals.c" file.
4159 6. Changed the handling of character classes; they are now done with a 32-byte
4160 bit map always.
4162 7. Added the -d and /D options to pcretest to make it possible to look at the
4163 internals of compilation without having to recompile pcre.
4166 Version 0.95 23-Sep-97
4167 ----------------------
4169 1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
4170 \x20 at the start of a run of normal characters. These were being treated as
4171 real characters, instead of the source characters being re-checked.
4174 Version 0.94 18-Sep-97
4175 ----------------------
4177 1. The functions are now thread-safe, with the caveat that the global variables
4178 containing pointers to malloc() and free() or alternative functions are the
4179 same for all threads.
4181 2. Get pcre_study() to generate a bitmap of initial characters for non-
4182 anchored patterns when this is possible, and use it if passed to pcre_exec().
4185 Version 0.93 15-Sep-97
4186 ----------------------
4188 1. /(b)|(:+)/ was computing an incorrect first character.
4190 2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
4191 but not actually doing anything yet.
4193 3. Treat "-" characters in classes that cannot be part of ranges as literals,
4194 as Perl does (e.g. [-az] or [az-]).
4196 4. Set the anchored flag if a branch starts with .* or .*? because that tests
4197 all possible positions.
4199 5. Split up into different modules to avoid including unneeded functions in a
4200 compiled binary. However, compile and exec are still in one module. The "study"
4201 function is split off.
4203 6. The character tables are now in a separate module whose source is generated
4204 by an auxiliary program - but can then be edited by hand if required. There are
4205 now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
4206 toupper() in the code.
4208 7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
4209 make them global. Abolish the function for setting them, as the caller can now
4210 set them directly.
4213 Version 0.92 11-Sep-97
4214 ----------------------
4216 1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
4217 (e.g. /a{1,3}/) was broken (I mis-optimized it).
4219 2. Caseless matching was not working in character classes if the characters in
4220 the pattern were in upper case.
4222 3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
4224 4. Make PCRE_ANCHORED public and accept as a compile option.
4226 5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
4227 PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
4228 pass them.
4230 6. Give an error if bad option bits passed at compile or run time.
4232 7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
4233 pcretest to cause it to pass that flag.
4235 8. Add pcre_info(), to get the number of identifying subpatterns, the stored
4236 options, and the first character, if set.
4238 9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
4241 Version 0.91 10-Sep-97
4242 ----------------------
4244 1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
4245 match the empty string as in /(a*)*/. It was looping and ultimately crashing.
4247 2. PCRE was looping on encountering an indefinitely repeated back reference to
4248 a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
4249 Perl does - treats the match as successful.
4251 ****


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