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Revision 595 - (show annotations)
Mon May 2 10:33:29 2011 UTC (4 years, 6 months ago) by ph10
File size: 199232 byte(s)
Error occurred while calculating annotation data.
Fix problems with caseless reference matching in UTF-8 mode when the 
upper/lower case characters have different lengths.
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).
25 Version 8.12 15-Jan-2011
26 ------------------------
28 1. Fixed some typos in the markup of the man pages, and wrote a script that
29 checks for such things as part of the documentation building process.
31 2. On a big-endian 64-bit system, pcregrep did not correctly process the
32 --match-limit and --recursion-limit options (added for 8.11). In
33 particular, this made one of the standard tests fail. (The integer value
34 went into the wrong half of a long int.)
36 3. If the --colour option was given to pcregrep with -v (invert match), it
37 did strange things, either producing crazy output, or crashing. It should,
38 of course, ignore a request for colour when reporting lines that do not
39 match.
41 4. Another pcregrep bug caused similar problems if --colour was specified with
42 -M (multiline) and the pattern match finished with a line ending.
44 5. In pcregrep, when a pattern that ended with a literal newline sequence was
45 matched in multiline mode, the following line was shown as part of the
46 match. This seems wrong, so I have changed it.
48 6. Another pcregrep bug in multiline mode, when --colour was specified, caused
49 the check for further matches in the same line (so they could be coloured)
50 to overrun the end of the current line. If another match was found, it was
51 incorrectly shown (and then shown again when found in the next line).
53 7. If pcregrep was compiled under Windows, there was a reference to the
54 function pcregrep_exit() before it was defined. I am assuming this was
55 the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
56 reported by a user. I've moved the definition above the reference.
59 Version 8.11 10-Dec-2010
60 ------------------------
62 1. (*THEN) was not working properly if there were untried alternatives prior
63 to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
64 backtracked to try for "b" instead of moving to the next alternative branch
65 at the same level (in this case, to look for "c"). The Perl documentation
66 is clear that when (*THEN) is backtracked onto, it goes to the "next
67 alternative in the innermost enclosing group".
69 2. (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
70 such as (A(*COMMIT)B(*THEN)C|D) any failure after matching A should
71 result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
72 (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
73 (*THEN).
75 3. If \s appeared in a character class, it removed the VT character from
76 the class, even if it had been included by some previous item, for example
77 in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
78 of \s, but is part of the POSIX "space" class.)
80 4. A partial match never returns an empty string (because you can always
81 match an empty string at the end of the subject); however the checking for
82 an empty string was starting at the "start of match" point. This has been
83 changed to the "earliest inspected character" point, because the returned
84 data for a partial match starts at this character. This means that, for
85 example, /(?<=abc)def/ gives a partial match for the subject "abc"
86 (previously it gave "no match").
88 5. Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
89 of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
90 previously a full match would be given. However, setting PCRE_PARTIAL_HARD
91 has an implication that the given string is incomplete (because a partial
92 match is preferred over a full match). For this reason, these items now
93 give a partial match in this situation. [Aside: previously, the one case
94 /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
95 match rather than a full match, which was wrong by the old rules, but is
96 now correct.]
98 6. There was a bug in the handling of #-introduced comments, recognized when
99 PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
100 If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
101 UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
102 scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
103 but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
104 places in pcre_compile().
106 7. Related to (6) above, when pcre_compile() was skipping #-introduced
107 comments when looking ahead for named forward references to subpatterns,
108 the only newline sequence it recognized was NL. It now handles newlines
109 according to the set newline convention.
111 8. SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
112 former, but used strtoul(), whereas pcretest avoided strtoul() but did not
113 cater for a lack of strerror(). These oversights have been fixed.
115 9. Added --match-limit and --recursion-limit to pcregrep.
117 10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
119 11. When the -o option was used, pcregrep was setting a return code of 1, even
120 when matches were found, and --line-buffered was not being honoured.
122 12. Added an optional parentheses number to the -o and --only-matching options
123 of pcregrep.
125 13. Imitating Perl's /g action for multiple matches is tricky when the pattern
126 can match an empty string. The code to do it in pcretest and pcredemo
127 needed fixing:
129 (a) When the newline convention was "crlf", pcretest got it wrong, skipping
130 only one byte after an empty string match just before CRLF (this case
131 just got forgotten; "any" and "anycrlf" were OK).
133 (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
134 mode when an empty string match preceded an ASCII character followed by
135 a non-ASCII character. (The code for advancing by one character rather
136 than one byte was nonsense.)
138 (c) The pcredemo.c sample program did not have any code at all to handle
139 the cases when CRLF is a valid newline sequence.
141 14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
142 as a starting offset was within the subject string. There is now a new
143 error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
144 negative or greater than the length of the string. In order to test this,
145 pcretest is extended to allow the setting of negative starting offsets.
147 15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
148 starting offset points to the beginning of a UTF-8 character was
149 unnecessarily clumsy. I tidied it up.
151 16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
152 bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
154 17. Nobody had reported that the --include_dir option, which was added in
155 release 7.7 should have been called --include-dir (hyphen, not underscore)
156 for compatibility with GNU grep. I have changed it to --include-dir, but
157 left --include_dir as an undocumented synonym, and the same for
158 --exclude-dir, though that is not available in GNU grep, at least as of
159 release 2.5.4.
161 18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
162 characters from a string of bytes) have been redefined so as not to use
163 loops, in order to improve performance in some environments. At the same
164 time, I abstracted some of the common code into auxiliary macros to save
165 repetition (this should not affect the compiled code).
167 19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
168 compile-time error is now given if \c is not followed by an ASCII
169 character, that is, a byte less than 128. (In EBCDIC mode, the code is
170 different, and any byte value is allowed.)
172 20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
173 START_OPTIMIZE option, which is now allowed at compile time - but just
174 passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
175 to pcregrep and other applications that have no direct access to PCRE
176 options. The new /Y option in pcretest sets this option when calling
177 pcre_compile().
179 21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
180 back references. Groups containing recursive back references were forced to
181 be atomic by that change, but in the case of named groups, the amount of
182 memory required was incorrectly computed, leading to "Failed: internal
183 error: code overflow". This has been fixed.
185 22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
186 pcretest.c, to avoid build problems in some Borland environments.
189 Version 8.10 25-Jun-2010
190 ------------------------
192 1. Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
193 THEN.
195 2. (*ACCEPT) was not working when inside an atomic group.
197 3. Inside a character class, \B is treated as a literal by default, but
198 faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
199 causes the error). The code is unchanged, but I tidied the documentation.
201 4. Inside a character class, PCRE always treated \R and \X as literals,
202 whereas Perl faults them if its -w option is set. I have changed PCRE so
203 that it faults them when PCRE_EXTRA is set.
205 5. Added support for \N, which always matches any character other than
206 newline. (It is the same as "." when PCRE_DOTALL is not set.)
208 6. When compiling pcregrep with newer versions of gcc which may have
209 FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
210 declared with attribute warn_unused_result" were given. Just casting the
211 result to (void) does not stop the warnings; a more elaborate fudge is
212 needed. I've used a macro to implement this.
214 7. Minor change to pcretest.c to avoid a compiler warning.
216 8. Added four artifical Unicode properties to help with an option to make
217 \s etc use properties (see next item). The new properties are: Xan
218 (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
220 9. Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
221 use Unicode properties. (*UCP) at the start of a pattern can be used to set
222 this option. Modified pcretest to add /W to test this facility. Added
223 REG_UCP to make it available via the POSIX interface.
225 10. Added --line-buffered to pcregrep.
227 11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
228 studied, and the match started with a letter with a code point greater than
229 127 whose first byte was different to the first byte of the other case of
230 the letter, the other case of this starting letter was not recognized
231 (#976).
233 12. If a pattern that was studied started with a repeated Unicode property
234 test, for example, \p{Nd}+, there was the theoretical possibility of
235 setting up an incorrect bitmap of starting bytes, but fortunately it could
236 not have actually happened in practice until change 8 above was made (it
237 added property types that matched character-matching opcodes).
239 13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
240 possible starting bytes for non-anchored patterns.
242 14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
243 \R, and also a number of cases that involve Unicode properties, both
244 explicit and implicit when PCRE_UCP is set.
246 15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
247 input, it could crash or give wrong results if characters with values
248 greater than 0xc0 were present in the subject string. (Detail: it assumed
249 UTF-8 input when processing these items.)
251 16. Added a lot of (int) casts to avoid compiler warnings in systems where
252 size_t is 64-bit (#991).
254 17. Added a check for running out of memory when PCRE is compiled with
255 --disable-stack-for-recursion (#990).
257 18. If the last data line in a file for pcretest does not have a newline on
258 the end, a newline was missing in the output.
260 19. The default pcre_chartables.c file recognizes only ASCII characters (values
261 less than 128) in its various bitmaps. However, there is a facility for
262 generating tables according to the current locale when PCRE is compiled. It
263 turns out that in some environments, 0x85 and 0xa0, which are Unicode space
264 characters, are recognized by isspace() and therefore were getting set in
265 these tables, and indeed these tables seem to approximate to ISO 8859. This
266 caused a problem in UTF-8 mode when pcre_study() was used to create a list
267 of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
268 which of course cannot start UTF-8 characters. I have changed the code so
269 that only real ASCII characters (less than 128) and the correct starting
270 bytes for UTF-8 encodings are set for characters greater than 127 when in
271 UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
272 altogether.)
274 20. Added the /T option to pcretest so as to be able to run tests with non-
275 standard character tables, thus making it possible to include the tests
276 used for 19 above in the standard set of tests.
278 21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
279 reference to a subpattern the other side of a comment that contains an
280 opening parenthesis caused either an internal compiling error, or a
281 reference to the wrong subpattern.
284 Version 8.02 19-Mar-2010
285 ------------------------
287 1. The Unicode data tables have been updated to Unicode 5.2.0.
289 2. Added the option --libs-cpp to pcre-config, but only when C++ support is
290 configured.
292 3. Updated the licensing terms in the pcregexp.pas file, as agreed with the
293 original author of that file, following a query about its status.
295 4. On systems that do not have stdint.h (e.g. Solaris), check for and include
296 inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
298 5. A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
299 quantifier applied to a forward-referencing subroutine call, could compile
300 incorrect code or give the error "internal error: previously-checked
301 referenced subpattern not found".
303 6. Both MS Visual Studio and Symbian OS have problems with initializing
304 variables to point to external functions. For these systems, therefore,
305 pcre_malloc etc. are now initialized to local functions that call the
306 relevant global functions.
308 7. There were two entries missing in the vectors called coptable and poptable
309 in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
310 I've fixed the data, and added a kludgy way of testing at compile time that
311 the lengths are correct (equal to the number of opcodes).
313 8. Following on from 7, I added a similar kludge to check the length of the
314 eint vector in pcreposix.c.
316 9. Error texts for pcre_compile() are held as one long string to avoid too
317 much relocation at load time. To find a text, the string is searched,
318 counting zeros. There was no check for running off the end of the string,
319 which could happen if a new error number was added without updating the
320 string.
322 10. \K gave a compile-time error if it appeared in a lookbehind assersion.
324 11. \K was not working if it appeared in an atomic group or in a group that
325 was called as a "subroutine", or in an assertion. Perl 5.11 documents that
326 \K is "not well defined" if used in an assertion. PCRE now accepts it if
327 the assertion is positive, but not if it is negative.
329 12. Change 11 fortuitously reduced the size of the stack frame used in the
330 "match()" function of pcre_exec.c by one pointer. Forthcoming
331 implementation of support for (*MARK) will need an extra pointer on the
332 stack; I have reserved it now, so that the stack frame size does not
333 decrease.
335 13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
336 item in branch that calls a recursion is a subroutine call - as in the
337 second branch in the above example - was incorrectly given the compile-
338 time error "recursive call could loop indefinitely" because pcre_compile()
339 was not correctly checking the subroutine for matching a non-empty string.
341 14. The checks for overrunning compiling workspace could trigger after an
342 overrun had occurred. This is a "should never occur" error, but it can be
343 triggered by pathological patterns such as hundreds of nested parentheses.
344 The checks now trigger 100 bytes before the end of the workspace.
346 15. Fix typo in configure.ac: "srtoq" should be "strtoq".
349 Version 8.01 19-Jan-2010
350 ------------------------
352 1. If a pattern contained a conditional subpattern with only one branch (in
353 particular, this includes all (*DEFINE) patterns), a call to pcre_study()
354 computed the wrong minimum data length (which is of course zero for such
355 subpatterns). This could cause incorrect "no match" results.
357 2. For patterns such as (?i)a(?-i)b|c where an option setting at the start of
358 the pattern is reset in the first branch, pcre_compile() failed with
359 "internal error: code overflow at offset...". This happened only when
360 the reset was to the original external option setting. (An optimization
361 abstracts leading options settings into an external setting, which was the
362 cause of this.)
364 3. A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
365 of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
366 assertion pattern did not match (meaning that the assertion was true), it
367 was incorrectly treated as false if the SKIP had been reached during the
368 matching. This also applied to assertions used as conditions.
370 4. If an item that is not supported by pcre_dfa_exec() was encountered in an
371 assertion subpattern, including such a pattern used as a condition,
372 unpredictable results occurred, instead of the error return
375 5. The C++ GlobalReplace function was not working like Perl for the special
376 situation when an empty string is matched. It now does the fancy magic
377 stuff that is necessary.
379 6. In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
380 removed. (These were left over from very, very early versions of PCRE.)
382 7. Some cosmetic changes to the code to make life easier when compiling it
383 as part of something else:
385 (a) Change DEBUG to PCRE_DEBUG.
387 (b) In pcre_compile(), rename the member of the "branch_chain" structure
388 called "current" as "current_branch", to prevent a collision with the
389 Linux macro when compiled as a kernel module.
391 (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
392 prevent a collision with the Linux macro when compiled as a kernel
393 module.
395 8. In pcre_compile() there are some checks for integer overflows that used to
396 cast potentially large values to (double). This has been changed to that
397 when building, a check for int64_t is made, and if it is found, it is used
398 instead, thus avoiding the use of floating point arithmetic. (There is no
399 other use of FP in PCRE.) If int64_t is not found, the fallback is to
400 double.
402 9. Added two casts to avoid signed/unsigned warnings from VS Studio Express
403 2005 (difference between two addresses compared to an unsigned value).
405 10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
406 custom one, because of the following reported problem in Windows:
408 - libbz2 uses the Pascal calling convention (WINAPI) for the functions
409 under Win32.
410 - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
411 therefore missing the function definition.
412 - The compiler thus generates a "C" signature for the test function.
413 - The linker fails to find the "C" function.
414 - PCRE fails to configure if asked to do so against libbz2.
416 11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
417 messages were output:
419 Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
420 rerunning libtoolize, to keep the correct libtool macros in-tree.
421 Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
423 I have done both of these things.
425 12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
426 most of the time, it *can* run out if it is given a pattern that contains a
427 runaway infinite recursion. I updated the discussion in the pcrestack man
428 page.
430 13. Now that we have gone to the x.xx style of version numbers, the minor
431 version may start with zero. Using 08 or 09 is a bad idea because users
432 might check the value of PCRE_MINOR in their code, and 08 or 09 may be
433 interpreted as invalid octal numbers. I've updated the previous comment in
434 configure.ac, and also added a check that gives an error if 08 or 09 are
435 used.
437 14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
438 causing partial matching to fail when the end of the subject matched \W
439 in a UTF-8 pattern where \W was quantified with a minimum of 3.
441 15. There were some discrepancies between the declarations in pcre_internal.h
442 of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
443 their definitions. The declarations used "const uschar *" and the
444 definitions used USPTR. Even though USPTR is normally defined as "const
445 unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
446 reported that: "This difference in casting confuses some C++ compilers, for
447 example, SunCC recognizes above declarations as different functions and
448 generates broken code for hbpcre." I have changed the declarations to use
449 USPTR.
451 16. GNU libtool is named differently on some systems. The autogen.sh script now
452 tries several variants such as glibtoolize (MacOSX) and libtoolize1x
453 (FreeBSD).
455 17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
456 (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
457 comment: "Figure out how to create a longlong from a string: strtoll and
458 equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
459 instance, but it only takes 2 args instead of 3!"
461 18. A subtle bug concerned with back references has been fixed by a change of
462 specification, with a corresponding code fix. A pattern such as
463 ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
464 refers, was giving matches when it shouldn't. For example, xa=xaaa would
465 match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
466 same bug. Such groups have to be quantified to be useful, or contained
467 inside another quantified group. (If there's no repetition, the reference
468 can never match.) The problem arises because, having left the group and
469 moved on to the rest of the pattern, a later failure that backtracks into
470 the group uses the captured value from the final iteration of the group
471 rather than the correct earlier one. I have fixed this in PCRE by forcing
472 any group that contains a reference to itself to be an atomic group; that
473 is, there cannot be any backtracking into it once it has completed. This is
474 similar to recursive and subroutine calls.
477 Version 8.00 19-Oct-09
478 ----------------------
480 1. The table for translating pcre_compile() error codes into POSIX error codes
481 was out-of-date, and there was no check on the pcre_compile() error code
482 being within the table. This could lead to an OK return being given in
483 error.
485 2. Changed the call to open a subject file in pcregrep from fopen(pathname,
486 "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
487 in a Windows environment.
489 3. The pcregrep --count option prints the count for each file even when it is
490 zero, as does GNU grep. However, pcregrep was also printing all files when
491 --files-with-matches was added. Now, when both options are given, it prints
492 counts only for those files that have at least one match. (GNU grep just
493 prints the file name in this circumstance, but including the count seems
494 more useful - otherwise, why use --count?) Also ensured that the
495 combination -clh just lists non-zero counts, with no names.
497 4. The long form of the pcregrep -F option was incorrectly implemented as
498 --fixed_strings instead of --fixed-strings. This is an incompatible change,
499 but it seems right to fix it, and I didn't think it was worth preserving
500 the old behaviour.
502 5. The command line items --regex=pattern and --regexp=pattern were not
503 recognized by pcregrep, which required --regex pattern or --regexp pattern
504 (with a space rather than an '='). The man page documented the '=' forms,
505 which are compatible with GNU grep; these now work.
507 6. No libpcreposix.pc file was created for pkg-config; there was just
508 libpcre.pc and libpcrecpp.pc. The omission has been rectified.
510 7. Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
511 when UCP support is not needed, by modifying the Python script that
512 generates it from Unicode data files. This should not matter if the module
513 is correctly used as a library, but I received one complaint about 50K of
514 unwanted data. My guess is that the person linked everything into his
515 program rather than using a library. Anyway, it does no harm.
517 8. A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
518 was a minimum greater than 1 for a wide character in a possessive
519 repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
520 which had an unlimited repeat of a nested, fixed maximum repeat of a wide
521 character. Chaos in the form of incorrect output or a compiling loop could
522 result.
524 9. The restrictions on what a pattern can contain when partial matching is
525 requested for pcre_exec() have been removed. All patterns can now be
526 partially matched by this function. In addition, if there are at least two
527 slots in the offset vector, the offset of the earliest inspected character
528 for the match and the offset of the end of the subject are set in them when
529 PCRE_ERROR_PARTIAL is returned.
531 10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
532 synonymous with PCRE_PARTIAL, for backwards compatibility, and
533 PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
534 and may be more useful for multi-segment matching.
536 11. Partial matching with pcre_exec() is now more intuitive. A partial match
537 used to be given if ever the end of the subject was reached; now it is
538 given only if matching could not proceed because another character was
539 needed. This makes a difference in some odd cases such as Z(*FAIL) with the
540 string "Z", which now yields "no match" instead of "partial match". In the
541 case of pcre_dfa_exec(), "no match" is given if every matching path for the
542 final character ended with (*FAIL).
544 12. Restarting a match using pcre_dfa_exec() after a partial match did not work
545 if the pattern had a "must contain" character that was already found in the
546 earlier partial match, unless partial matching was again requested. For
547 example, with the pattern /dog.(body)?/, the "must contain" character is
548 "g". If the first part-match was for the string "dog", restarting with
549 "sbody" failed. This bug has been fixed.
551 13. The string returned by pcre_dfa_exec() after a partial match has been
552 changed so that it starts at the first inspected character rather than the
553 first character of the match. This makes a difference only if the pattern
554 starts with a lookbehind assertion or \b or \B (\K is not supported by
555 pcre_dfa_exec()). It's an incompatible change, but it makes the two
556 matching functions compatible, and I think it's the right thing to do.
558 14. Added a pcredemo man page, created automatically from the pcredemo.c file,
559 so that the demonstration program is easily available in environments where
560 PCRE has not been installed from source.
562 15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
563 libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
564 library.
566 16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
567 It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
568 is not the first non-POSIX option to be added. Clearly some people find
569 these options useful.
571 17. If a caller to the POSIX matching function regexec() passes a non-zero
572 value for nmatch with a NULL value for pmatch, the value of
573 nmatch is forced to zero.
575 18. RunGrepTest did not have a test for the availability of the -u option of
576 the diff command, as RunTest does. It now checks in the same way as
577 RunTest, and also checks for the -b option.
579 19. If an odd number of negated classes containing just a single character
580 interposed, within parentheses, between a forward reference to a named
581 subpattern and the definition of the subpattern, compilation crashed with
582 an internal error, complaining that it could not find the referenced
583 subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
584 [The bug was that it was starting one character too far in when skipping
585 over the character class, thus treating the ] as data rather than
586 terminating the class. This meant it could skip too much.]
588 20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
589 /g option in pcretest when the pattern contains \K, which makes it possible
590 to have an empty string match not at the start, even when the pattern is
591 anchored. Updated pcretest and pcredemo to use this option.
593 21. If the maximum number of capturing subpatterns in a recursion was greater
594 than the maximum at the outer level, the higher number was returned, but
595 with unset values at the outer level. The correct (outer level) value is
596 now given.
598 22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
599 PCRE did not set those parentheses (unlike Perl). I have now found a way to
600 make it do so. The string so far is captured, making this feature
601 compatible with Perl.
603 23. The tests have been re-organized, adding tests 11 and 12, to make it
604 possible to check the Perl 5.10 features against Perl 5.10.
606 24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
607 pattern matches a fixed length string. PCRE did not allow this; now it
608 does. Neither allows recursion.
610 25. I finally figured out how to implement a request to provide the minimum
611 length of subject string that was needed in order to match a given pattern.
612 (It was back references and recursion that I had previously got hung up
613 on.) This code has now been added to pcre_study(); it finds a lower bound
614 to the length of subject needed. It is not necessarily the greatest lower
615 bound, but using it to avoid searching strings that are too short does give
616 some useful speed-ups. The value is available to calling programs via
617 pcre_fullinfo().
619 26. While implementing 25, I discovered to my embarrassment that pcretest had
620 not been passing the result of pcre_study() to pcre_dfa_exec(), so the
621 study optimizations had never been tested with that matching function.
622 Oops. What is worse, even when it was passed study data, there was a bug in
623 pcre_dfa_exec() that meant it never actually used it. Double oops. There
624 were also very few tests of studied patterns with pcre_dfa_exec().
626 27. If (?| is used to create subpatterns with duplicate numbers, they are now
627 allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
628 on the other side of the coin, they are no longer allowed to have different
629 names, because these cannot be distinguished in PCRE, and this has caused
630 confusion. (This is a difference from Perl.)
632 28. When duplicate subpattern names are present (necessarily with different
633 numbers, as required by 27 above), and a test is made by name in a
634 conditional pattern, either for a subpattern having been matched, or for
635 recursion in such a pattern, all the associated numbered subpatterns are
636 tested, and the overall condition is true if the condition is true for any
637 one of them. This is the way Perl works, and is also more like the way
638 testing by number works.
641 Version 7.9 11-Apr-09
642 ---------------------
644 1. When building with support for bzlib/zlib (pcregrep) and/or readline
645 (pcretest), all targets were linked against these libraries. This included
646 libpcre, libpcreposix, and libpcrecpp, even though they do not use these
647 libraries. This caused unwanted dependencies to be created. This problem
648 has been fixed, and now only pcregrep is linked with bzlib/zlib and only
649 pcretest is linked with readline.
651 2. The "typedef int BOOL" in pcre_internal.h that was included inside the
652 "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
653 moved outside it again, because FALSE and TRUE are already defined in AIX,
654 but BOOL is not.
656 3. The pcre_config() function was treating the PCRE_MATCH_LIMIT and
657 PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
659 4. The pcregrep documentation said spaces were inserted as well as colons (or
660 hyphens) following file names and line numbers when outputting matching
661 lines. This is not true; no spaces are inserted. I have also clarified the
662 wording for the --colour (or --color) option.
664 5. In pcregrep, when --colour was used with -o, the list of matching strings
665 was not coloured; this is different to GNU grep, so I have changed it to be
666 the same.
668 6. When --colo(u)r was used in pcregrep, only the first matching substring in
669 each matching line was coloured. Now it goes on to look for further matches
670 of any of the test patterns, which is the same behaviour as GNU grep.
672 7. A pattern that could match an empty string could cause pcregrep to loop; it
673 doesn't make sense to accept an empty string match in pcregrep, so I have
674 locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
675 seems to be how GNU grep behaves.
677 8. The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
678 start or after a newline", because the conditional assertion was not being
679 correctly handled. The rule now is that both the assertion and what follows
680 in the first alternative must satisfy the test.
682 9. If auto-callout was enabled in a pattern with a conditional group whose
683 condition was an assertion, PCRE could crash during matching, both with
684 pcre_exec() and pcre_dfa_exec().
686 10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
687 used for matching.
689 11. Unicode property support in character classes was not working for
690 characters (bytes) greater than 127 when not in UTF-8 mode.
692 12. Added the -M command line option to pcretest.
694 14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
696 15. Added the PCRE_NO_START_OPTIMIZE match-time option.
698 16. Added comments and documentation about mis-use of no_arg in the C++
699 wrapper.
701 17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
702 from Martin Jerabek that uses macro names for all relevant character and
703 string constants.
705 18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
706 SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
707 SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
708 these, but not everybody uses configure.
710 19. A conditional group that had only one branch was not being correctly
711 recognized as an item that could match an empty string. This meant that an
712 enclosing group might also not be so recognized, causing infinite looping
713 (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
714 with the subject "ab", where knowledge that the repeated group can match
715 nothing is needed in order to break the loop.
717 20. If a pattern that was compiled with callouts was matched using pcre_dfa_
718 exec(), but without supplying a callout function, matching went wrong.
720 21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
721 leak if the size of the offset vector was greater than 30. When the vector
722 is smaller, the saved offsets during recursion go onto a local stack
723 vector, but for larger vectors malloc() is used. It was failing to free
724 when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
725 error, in fact).
727 22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
728 heapframe that is used only when UTF-8 support is enabled. This caused no
729 problem, but was untidy.
731 23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
732 CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
733 included within another project.
735 24. Steven Van Ingelgem's patches to add more options to the CMake support,
736 slightly modified by me:
738 (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
739 not building pcregrep.
741 (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
742 if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
744 25. Forward references, both numeric and by name, in patterns that made use of
745 duplicate group numbers, could behave incorrectly or give incorrect errors,
746 because when scanning forward to find the reference group, PCRE was not
747 taking into account the duplicate group numbers. A pattern such as
748 ^X(?3)(a)(?|(b)|(q))(Y) is an example.
750 26. Changed a few more instances of "const unsigned char *" to USPTR, making
751 the feature of a custom pointer more persuasive (as requested by a user).
753 27. Wrapped the definitions of fileno and isatty for Windows, which appear in
754 pcretest.c, inside #ifndefs, because it seems they are sometimes already
755 pre-defined.
757 28. Added support for (*UTF8) at the start of a pattern.
759 29. Arrange for flags added by the "release type" setting in CMake to be shown
760 in the configuration summary.
763 Version 7.8 05-Sep-08
764 ---------------------
766 1. Replaced UCP searching code with optimized version as implemented for Ad
767 Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
768 stage table and inline lookup instead of a function, giving speed ups of 2
769 to 5 times on some simple patterns that I tested. Permission was given to
770 distribute the MultiStage2.py script that generates the tables (it's not in
771 the tarball, but is in the Subversion repository).
773 2. Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
774 scripts.
776 3. Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
777 a group with a zero qualifier. The result of the study could be incorrect,
778 or the function might crash, depending on the pattern.
780 4. Caseless matching was not working for non-ASCII characters in back
781 references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
782 It now works when Unicode Property Support is available.
784 5. In pcretest, an escape such as \x{de} in the data was always generating
785 a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
786 non-UTF-8 mode. If the value is greater than 255, it gives a warning about
787 truncation.
789 6. Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
791 7. Added two (int) casts to pcregrep when printing the difference of two
792 pointers, in case they are 64-bit values.
794 8. Added comments about Mac OS X stack usage to the pcrestack man page and to
795 test 2 if it fails.
797 9. Added PCRE_CALL_CONVENTION just before the names of all exported functions,
798 and a #define of that name to empty if it is not externally set. This is to
799 allow users of MSVC to set it if necessary.
801 10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
802 the convenience functions in the pcre_get.c source file.
804 11. An option change at the start of a pattern that had top-level alternatives
805 could cause overwriting and/or a crash. This command provoked a crash in
806 some environments:
808 printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
810 This potential security problem was recorded as CVE-2008-2371.
812 12. For a pattern where the match had to start at the beginning or immediately
813 after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
814 pcre_dfa_exec() could read past the end of the passed subject if there was
815 no match. To help with detecting such bugs (e.g. with valgrind), I modified
816 pcretest so that it places the subject at the end of its malloc-ed buffer.
818 13. The change to pcretest in 12 above threw up a couple more cases when pcre_
819 exec() might read past the end of the data buffer in UTF-8 mode.
821 14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
822 the data contained the byte 0x85 as part of a UTF-8 character within its
823 first line. This applied both to normal and DFA matching.
825 15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
826 /^[^d]*?$/8 failed to match "abc".
828 16. Added a missing copyright notice to pcrecpp_internal.h.
830 17. Make it more clear in the documentation that values returned from
831 pcre_exec() in ovector are byte offsets, not character counts.
833 18. Tidied a few places to stop certain compilers from issuing warnings.
835 19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
836 supplied by Stefan Weber. I made a further small update for 7.8 because
837 there is a change of source arrangements: the pcre_searchfuncs.c module is
838 replaced by pcre_ucd.c.
841 Version 7.7 07-May-08
842 ---------------------
844 1. Applied Craig's patch to sort out a long long problem: "If we can't convert
845 a string to a long long, pretend we don't even have a long long." This is
846 done by checking for the strtoq, strtoll, and _strtoi64 functions.
848 2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
849 pre-7.6 versions, which defined a global no_arg variable instead of putting
850 it in the RE class. (See also #8 below.)
852 3. Remove a line of dead code, identified by coverity and reported by Nuno
853 Lopes.
855 4. Fixed two related pcregrep bugs involving -r with --include or --exclude:
857 (1) The include/exclude patterns were being applied to the whole pathnames
858 of files, instead of just to the final components.
860 (2) If there was more than one level of directory, the subdirectories were
861 skipped unless they satisfied the include/exclude conditions. This is
862 inconsistent with GNU grep (and could even be seen as contrary to the
863 pcregrep specification - which I improved to make it absolutely clear).
864 The action now is always to scan all levels of directory, and just
865 apply the include/exclude patterns to regular files.
867 5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used
868 --exclude_dir in the tests to avoid scanning .svn directories.
870 6. Applied Craig's patch to the QuoteMeta function so that it escapes the
871 NUL character as backslash + 0 rather than backslash + NUL, because PCRE
872 doesn't support NULs in patterns.
874 7. Added some missing "const"s to declarations of static tables in
875 pcre_compile.c and pcre_dfa_exec.c.
877 8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
878 caused by fix #2 above. (Subsequently also a second patch to fix the
879 first patch. And a third patch - this was a messy problem.)
881 9. Applied Craig's patch to remove the use of push_back().
883 10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
884 matching function regexec().
886 11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
887 which, however, unlike Perl's \g{...}, are subroutine calls, not back
888 references. PCRE supports relative numbers with this syntax (I don't think
889 Oniguruma does).
891 12. Previously, a group with a zero repeat such as (...){0} was completely
892 omitted from the compiled regex. However, this means that if the group
893 was called as a subroutine from elsewhere in the pattern, things went wrong
894 (an internal error was given). Such groups are now left in the compiled
895 pattern, with a new opcode that causes them to be skipped at execution
896 time.
898 13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
899 to the way PCRE behaves:
901 (a) A lone ] character is dis-allowed (Perl treats it as data).
903 (b) A back reference to an unmatched subpattern matches an empty string
904 (Perl fails the current match path).
906 (c) A data ] in a character class must be notated as \] because if the
907 first data character in a class is ], it defines an empty class. (In
908 Perl it is not possible to have an empty class.) The empty class []
909 never matches; it forces failure and is equivalent to (*FAIL) or (?!).
910 The negative empty class [^] matches any one character, independently
911 of the DOTALL setting.
913 14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
914 non-existent subpattern following a character class starting with ']' and
915 containing () gave an internal compiling error instead of "reference to
916 non-existent subpattern". Fortunately, when the pattern did exist, the
917 compiled code was correct. (When scanning forwards to check for the
918 existencd of the subpattern, it was treating the data ']' as terminating
919 the class, so got the count wrong. When actually compiling, the reference
920 was subsequently set up correctly.)
922 15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
923 it was being rejected as not supported by pcre_dfa_exec(), even though
924 other assertions are supported. I have made pcre_dfa_exec() support
925 (*FAIL).
927 16. The implementation of 13c above involved the invention of a new opcode,
928 OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
929 cannot be changed at match time, I realized I could make a small
930 improvement to matching performance by compiling OP_ALLANY instead of
931 OP_ANY for "." when DOTALL was set, and then removing the runtime tests
932 on the OP_ANY path.
934 17. Compiling pcretest on Windows with readline support failed without the
935 following two fixes: (1) Make the unistd.h include conditional on
936 HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
938 18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
939 ncurses library to be included for pcretest when ReadLine support is
940 requested, but also to allow for it to be overridden. This patch came from
941 Daniel Bergström.
943 19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
944 as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
945 any errors with the current Unicode tables. Thanks to Peter Kankowski for
946 spotting this.
949 Version 7.6 28-Jan-08
950 ---------------------
952 1. A character class containing a very large number of characters with
953 codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
954 overflow.
956 2. Patch to cut out the "long long" test in pcrecpp_unittest when
957 HAVE_LONG_LONG is not defined.
959 3. Applied Christian Ehrlicher's patch to update the CMake build files to
960 bring them up to date and include new features. This patch includes:
962 - Fixed PH's badly added libz and libbz2 support.
963 - Fixed a problem with static linking.
964 - Added pcredemo. [But later removed - see 7 below.]
965 - Fixed dftables problem and added an option.
966 - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
968 - Added readline support for pcretest.
969 - Added an listing of the option settings after cmake has run.
971 4. A user submitted a patch to Makefile that makes it easy to create
972 "pcre.dll" under mingw when using Configure/Make. I added stuff to
973 Makefile.am that cause it to include this special target, without
974 affecting anything else. Note that the same mingw target plus all
975 the other distribution libraries and programs are now supported
976 when configuring with CMake (see 6 below) instead of with
977 Configure/Make.
979 5. Applied Craig's patch that moves no_arg into the RE class in the C++ code.
980 This is an attempt to solve the reported problem "pcrecpp::no_arg is not
981 exported in the Windows port". It has not yet been confirmed that the patch
982 solves the problem, but it does no harm.
984 6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
985 NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
986 with CMake, and also correct the comment about stack recursion.
988 7. Remove the automatic building of pcredemo from the ./configure system and
989 from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
990 of a program that users should build themselves after PCRE is installed, so
991 building it automatically is not really right. What is more, it gave
992 trouble in some build environments.
994 8. Further tidies to CMakeLists.txt from Sheri and Christian.
997 Version 7.5 10-Jan-08
998 ---------------------
1000 1. Applied a patch from Craig: "This patch makes it possible to 'ignore'
1001 values in parens when parsing an RE using the C++ wrapper."
1003 2. Negative specials like \S did not work in character classes in UTF-8 mode.
1004 Characters greater than 255 were excluded from the class instead of being
1005 included.
1007 3. The same bug as (2) above applied to negated POSIX classes such as
1008 [:^space:].
1010 4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
1011 defined or documented. It seems to have been a typo for PCRE_STATIC, so
1012 I have changed it.
1014 5. The construct (?&) was not diagnosed as a syntax error (it referenced the
1015 first named subpattern) and a construct such as (?&a) would reference the
1016 first named subpattern whose name started with "a" (in other words, the
1017 length check was missing). Both these problems are fixed. "Subpattern name
1018 expected" is now given for (?&) (a zero-length name), and this patch also
1019 makes it give the same error for \k'' (previously it complained that that
1020 was a reference to a non-existent subpattern).
1022 6. The erroneous patterns (?+-a) and (?-+a) give different error messages;
1023 this is right because (?- can be followed by option settings as well as by
1024 digits. I have, however, made the messages clearer.
1026 7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
1027 than the number used in the conditional) now cause a compile-time error.
1028 This is actually not compatible with Perl, which accepts such patterns, but
1029 treats the conditional as always being FALSE (as PCRE used to), but it
1030 seems to me that giving a diagnostic is better.
1032 8. Change "alphameric" to the more common word "alphanumeric" in comments
1033 and messages.
1035 9. Fix two occurrences of "backslash" in comments that should have been
1036 "backspace".
1038 10. Remove two redundant lines of code that can never be obeyed (their function
1039 was moved elsewhere).
1041 11. The program that makes PCRE's Unicode character property table had a bug
1042 which caused it to generate incorrect table entries for sequences of
1043 characters that have the same character type, but are in different scripts.
1044 It amalgamated them into a single range, with the script of the first of
1045 them. In other words, some characters were in the wrong script. There were
1046 thirteen such cases, affecting characters in the following ranges:
1048 U+002b0 - U+002c1
1049 U+0060c - U+0060d
1050 U+0061e - U+00612
1051 U+0064b - U+0065e
1052 U+0074d - U+0076d
1053 U+01800 - U+01805
1054 U+01d00 - U+01d77
1055 U+01d9b - U+01dbf
1056 U+0200b - U+0200f
1057 U+030fc - U+030fe
1058 U+03260 - U+0327f
1059 U+0fb46 - U+0fbb1
1060 U+10450 - U+1049d
1062 12. The -o option (show only the matching part of a line) for pcregrep was not
1063 compatible with GNU grep in that, if there was more than one match in a
1064 line, it showed only the first of them. It now behaves in the same way as
1065 GNU grep.
1067 13. If the -o and -v options were combined for pcregrep, it printed a blank
1068 line for every non-matching line. GNU grep prints nothing, and pcregrep now
1069 does the same. The return code can be used to tell if there were any
1070 non-matching lines.
1072 14. Added --file-offsets and --line-offsets to pcregrep.
1074 15. The pattern (?=something)(?R) was not being diagnosed as a potentially
1075 infinitely looping recursion. The bug was that positive lookaheads were not
1076 being skipped when checking for a possible empty match (negative lookaheads
1077 and both kinds of lookbehind were skipped).
1079 16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
1080 inclusion of <windows.h> to before rather than after the definition of
1081 INVALID_FILE_ATTRIBUTES (patch from David Byron).
1083 17. Specifying a possessive quantifier with a specific limit for a Unicode
1084 character property caused pcre_compile() to compile bad code, which led at
1085 runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
1086 are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
1087 caused the error; without that there was no problem.
1089 18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
1091 19. Added --enable-pcretest-libreadline.
1093 20. In pcrecpp.cc, the variable 'count' was incremented twice in
1094 RE::GlobalReplace(). As a result, the number of replacements returned was
1095 double what it should be. I removed one of the increments, but Craig sent a
1096 later patch that removed the other one (the right fix) and added unit tests
1097 that check the return values (which was not done before).
1099 21. Several CMake things:
1101 (1) Arranged that, when cmake is used on Unix, the libraries end up with
1102 the names libpcre and libpcreposix, not just pcre and pcreposix.
1104 (2) The above change means that pcretest and pcregrep are now correctly
1105 linked with the newly-built libraries, not previously installed ones.
1109 22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
1110 crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
1111 UTF-8 newline character). The key issue is that the pattern starts .*;
1112 this means that the match must be either at the beginning, or after a
1113 newline. The bug was in the code for advancing after a failed match and
1114 checking that the new position followed a newline. It was not taking
1115 account of UTF-8 characters correctly.
1117 23. PCRE was behaving differently from Perl in the way it recognized POSIX
1118 character classes. PCRE was not treating the sequence [:...:] as a
1119 character class unless the ... were all letters. Perl, however, seems to
1120 allow any characters between [: and :], though of course it rejects as
1121 unknown any "names" that contain non-letters, because all the known class
1122 names consist only of letters. Thus, Perl gives an error for [[:1234:]],
1123 for example, whereas PCRE did not - it did not recognize a POSIX character
1124 class. This seemed a bit dangerous, so the code has been changed to be
1125 closer to Perl. The behaviour is not identical to Perl, because PCRE will
1126 diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
1127 treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
1128 Perl does, and where it didn't before.
1130 24. Rewrite so as to remove the single use of %n from pcregrep because in some
1131 Windows environments %n is disabled by default.
1134 Version 7.4 21-Sep-07
1135 ---------------------
1137 1. Change 7.3/28 was implemented for classes by looking at the bitmap. This
1138 means that a class such as [\s] counted as "explicit reference to CR or
1139 LF". That isn't really right - the whole point of the change was to try to
1140 help when there was an actual mention of one of the two characters. So now
1141 the change happens only if \r or \n (or a literal CR or LF) character is
1142 encountered.
1144 2. The 32-bit options word was also used for 6 internal flags, but the numbers
1145 of both had grown to the point where there were only 3 bits left.
1146 Fortunately, there was spare space in the data structure, and so I have
1147 moved the internal flags into a new 16-bit field to free up more option
1148 bits.
1150 3. The appearance of (?J) at the start of a pattern set the DUPNAMES option,
1151 but did not set the internal JCHANGED flag - either of these is enough to
1152 control the way the "get" function works - but the PCRE_INFO_JCHANGED
1153 facility is supposed to tell if (?J) was ever used, so now (?J) at the
1154 start sets both bits.
1156 4. Added options (at build time, compile time, exec time) to change \R from
1157 matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
1159 5. doc/pcresyntax.html was missing from the distribution.
1161 6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
1162 compatibility, even though it is no longer used.
1164 7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
1165 strtoull to pcrecpp.cc to select the available functions in WIN32 when the
1166 windows.h file is present (where different names are used). [This was
1167 reversed later after testing - see 16 below.]
1169 8. Changed all #include <config.h> to #include "config.h". There were also
1170 some further <pcre.h> cases that I changed to "pcre.h".
1172 9. When pcregrep was used with the --colour option, it missed the line ending
1173 sequence off the lines that it output.
1175 10. It was pointed out to me that arrays of string pointers cause lots of
1176 relocations when a shared library is dynamically loaded. A technique of
1177 using a single long string with a table of offsets can drastically reduce
1178 these. I have refactored PCRE in four places to do this. The result is
1179 dramatic:
1181 Originally: 290
1182 After changing UCP table: 187
1183 After changing error message table: 43
1184 After changing table of "verbs" 36
1185 After changing table of Posix names 22
1187 Thanks to the folks working on Gregex for glib for this insight.
1189 11. --disable-stack-for-recursion caused compiling to fail unless -enable-
1190 unicode-properties was also set.
1192 12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
1194 13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
1195 checked only for CRLF.
1197 14. Added casts to pcretest.c to avoid compiler warnings.
1199 15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
1201 16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
1202 and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
1203 entirely. This removes changes made in 7 above.
1205 17. The CMake files have been updated, and there is now more information about
1206 building with CMake in the NON-UNIX-USE document.
1209 Version 7.3 28-Aug-07
1210 ---------------------
1212 1. In the rejigging of the build system that eventually resulted in 7.1, the
1213 line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
1214 brackets there is not right, since it causes compilers to look for an
1215 installed pcre.h, not the version that is in the source that is being
1216 compiled (which of course may be different). I have changed it back to:
1218 #include "pcre.h"
1220 I have a vague recollection that the change was concerned with compiling in
1221 different directories, but in the new build system, that is taken care of
1222 by the VPATH setting the Makefile.
1224 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
1225 when the subject happened to end in the byte 0x85 (e.g. if the last
1226 character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
1227 characters but of course it shouldn't be taken as a newline when it is part
1228 of another character. The bug was that, for an unlimited repeat of . in
1229 not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
1230 characters when looking for a newline.
1232 3. A small performance improvement in the DOTALL UTF-8 mode .* case.
1234 4. Debugging: adjusted the names of opcodes for different kinds of parentheses
1235 in debug output.
1237 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
1238 long printing in the pcrecpp unittest when running under MinGW.
1240 6. ESC_K was left out of the EBCDIC table.
1242 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
1243 parentheses; I made it 1000, which seemed large enough. Unfortunately, the
1244 limit also applies to "virtual nesting" when a pattern is recursive, and in
1245 this case 1000 isn't so big. I have been able to remove this limit at the
1246 expense of backing off one optimization in certain circumstances. Normally,
1247 when pcre_exec() would call its internal match() function recursively and
1248 immediately return the result unconditionally, it uses a "tail recursion"
1249 feature to save stack. However, when a subpattern that can match an empty
1250 string has an unlimited repetition quantifier, it no longer makes this
1251 optimization. That gives it a stack frame in which to save the data for
1252 checking that an empty string has been matched. Previously this was taken
1253 from the 1000-entry workspace that had been reserved. So now there is no
1254 explicit limit, but more stack is used.
1256 8. Applied Daniel's patches to solve problems with the import/export magic
1257 syntax that is required for Windows, and which was going wrong for the
1258 pcreposix and pcrecpp parts of the library. These were overlooked when this
1259 problem was solved for the main library.
1261 9. There were some crude static tests to avoid integer overflow when computing
1262 the size of patterns that contain repeated groups with explicit upper
1263 limits. As the maximum quantifier is 65535, the maximum group length was
1264 set at 30,000 so that the product of these two numbers did not overflow a
1265 32-bit integer. However, it turns out that people want to use groups that
1266 are longer than 30,000 bytes (though not repeat them that many times).
1267 Change 7.0/17 (the refactoring of the way the pattern size is computed) has
1268 made it possible to implement the integer overflow checks in a much more
1269 dynamic way, which I have now done. The artificial limitation on group
1270 length has been removed - we now have only the limit on the total length of
1271 the compiled pattern, which depends on the LINK_SIZE setting.
1273 10. Fixed a bug in the documentation for get/copy named substring when
1274 duplicate names are permitted. If none of the named substrings are set, the
1275 functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
1276 empty string.
1278 11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
1279 instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
1280 because the ] is interpreted as the first data character and the
1281 terminating ] is not found. PCRE has been made compatible with Perl in this
1282 regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
1283 cause memory overwriting.
1285 10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
1286 string has been matched (to stop an infinite loop). It was not recognizing
1287 a conditional subpattern that could match an empty string if that
1288 subpattern was within another subpattern. For example, it looped when
1289 trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the
1290 condition was not nested. This bug has been fixed.
1292 12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
1293 past the start of the subject in the presence of bytes with the top bit
1294 set, for example "\x8aBCD".
1296 13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
1297 (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
1299 14. Optimized (?!) to (*FAIL).
1301 15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
1302 This restricts code points to be within the range 0 to 0x10FFFF, excluding
1303 the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
1304 full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
1305 does: it's just the validity check that is more restrictive.
1307 16. Inserted checks for integer overflows during escape sequence (backslash)
1308 processing, and also fixed erroneous offset values for syntax errors during
1309 backslash processing.
1311 17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
1312 for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
1314 18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
1315 caused an overrun.
1317 19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
1318 something other than just ASCII characters) inside a group that had an
1319 unlimited repeat caused a loop at compile time (while checking to see
1320 whether the group could match an empty string).
1322 20. Debugging a pattern containing \p or \P could cause a crash. For example,
1323 [\P{Any}] did so. (Error in the code for printing property names.)
1325 21. An orphan \E inside a character class could cause a crash.
1327 22. A repeated capturing bracket such as (A)? could cause a wild memory
1328 reference during compilation.
1330 23. There are several functions in pcre_compile() that scan along a compiled
1331 expression for various reasons (e.g. to see if it's fixed length for look
1332 behind). There were bugs in these functions when a repeated \p or \P was
1333 present in the pattern. These operators have additional parameters compared
1334 with \d, etc, and these were not being taken into account when moving along
1335 the compiled data. Specifically:
1337 (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
1338 length.
1340 (b) An item such as \pL+ within a repeated group could cause crashes or
1341 loops.
1343 (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
1344 "reference to non-existent subpattern" error.
1346 (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
1348 24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
1349 characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
1351 25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
1353 26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
1354 character were causing crashes (broken optimization).
1356 27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
1357 \p or \P) caused a compile-time loop.
1359 28. More problems have arisen in unanchored patterns when CRLF is a valid line
1360 break. For example, the unstudied pattern [\r\n]A does not match the string
1361 "\r\nA" because change 7.0/46 below moves the current point on by two
1362 characters after failing to match at the start. However, the pattern \nA
1363 *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
1364 the same is true. There doesn't seem any very clean way out of this, but
1365 what I have chosen to do makes the common cases work: PCRE now takes note
1366 of whether there can be an explicit match for \r or \n anywhere in the
1367 pattern, and if so, 7.0/46 no longer applies. As part of this change,
1368 there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
1369 pattern has explicit CR or LF references.
1371 29. Added (*CR) etc for changing newline setting at start of pattern.
1374 Version 7.2 19-Jun-07
1375 ---------------------
1377 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
1378 which is apparently normally available under Windows.
1380 2. Re-jig the pcregrep tests with different newline settings in an attempt
1381 to make them independent of the local environment's newline setting.
1383 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
1385 4. Some of the "internals" tests were previously cut out when the link size
1386 was not 2, because the output contained actual offsets. The recent new
1387 "Z" feature of pcretest means that these can be cut out, making the tests
1388 usable with all link sizes.
1390 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
1391 stack recursion. This gives a massive performance boost under BSD, but just
1392 a small improvement under Linux. However, it saves one field in the frame
1393 in all cases.
1395 6. Added more features from the forthcoming Perl 5.10:
1397 (a) (?-n) (where n is a string of digits) is a relative subroutine or
1398 recursion call. It refers to the nth most recently opened parentheses.
1400 (b) (?+n) is also a relative subroutine call; it refers to the nth next
1401 to be opened parentheses.
1403 (c) Conditions that refer to capturing parentheses can be specified
1404 relatively, for example, (?(-2)... or (?(+3)...
1406 (d) \K resets the start of the current match so that everything before
1407 is not part of it.
1409 (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
1411 (f) \g{name} is another synonym - part of Perl 5.10's unification of
1412 reference syntax.
1414 (g) (?| introduces a group in which the numbering of parentheses in each
1415 alternative starts with the same number.
1417 (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
1419 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
1422 8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not
1423 terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
1424 for detecting groups that can match an empty string.
1426 9. A pattern with a very large number of alternatives (more than several
1427 hundred) was running out of internal workspace during the pre-compile
1428 phase, where pcre_compile() figures out how much memory will be needed. A
1429 bit of new cunning has reduced the workspace needed for groups with
1430 alternatives. The 1000-alternative test pattern now uses 12 bytes of
1431 workspace instead of running out of the 4096 that are available.
1433 10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
1435 11. Applied patch from Google to remove an optimization that didn't quite work.
1436 The report of the bug said:
1438 pcrecpp::RE("a*").FullMatch("aaa") matches, while
1439 pcrecpp::RE("a*?").FullMatch("aaa") does not, and
1440 pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
1442 12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
1443 it matched the wrong number of bytes.
1446 Version 7.1 24-Apr-07
1447 ---------------------
1449 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
1450 that is more "standard", making use of automake and other Autotools. There
1451 is some re-arrangement of the files and adjustment of comments consequent
1452 on this.
1454 2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
1455 for recursive directory scanning broke on some systems because the files
1456 are not scanned in any specific order and on different systems the order
1457 was different. A call to "sort" has been inserted into RunGrepTest for the
1458 approprate test as a short-term fix. In the longer term there may be an
1459 alternative.
1461 3. I had an email from Eric Raymond about problems translating some of PCRE's
1462 man pages to HTML (despite the fact that I distribute HTML pages, some
1463 people do their own conversions for various reasons). The problems
1464 concerned the use of low-level troff macros .br and .in. I have therefore
1465 removed all such uses from the man pages (some were redundant, some could
1466 be replaced by .nf/.fi pairs). The 132html script that I use to generate
1467 HTML has been updated to handle .nf/.fi and to complain if it encounters
1468 .br or .in.
1470 4. Updated comments in configure.ac that get placed in config.h.in and also
1471 arranged for config.h to be included in the distribution, with the name
1472 config.h.generic, for the benefit of those who have to compile without
1473 Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
1475 5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
1476 Weber: (1) pcre_internal.h was missing some function renames; (2) updated
1477 makevp.bat for the current PCRE, using the additional files
1478 makevp_c.txt, makevp_l.txt, and pcregexp.pas.
1480 6. A Windows user reported a minor discrepancy with test 2, which turned out
1481 to be caused by a trailing space on an input line that had got lost in his
1482 copy. The trailing space was an accident, so I've just removed it.
1484 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
1485 that is needed.
1487 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
1488 as "const" (a) because they are and (b) because it helps the PHP
1489 maintainers who have recently made a script to detect big data structures
1490 in the php code that should be moved to the .rodata section. I remembered
1491 to update Builducptable as well, so it won't revert if ucptable.h is ever
1492 re-created.
1494 9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
1495 pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
1496 order to be able to cut out the UTF-8 tables in the latter when UTF-8
1497 support is not required. This saves 1.5-2K of code, which is important in
1498 some applications.
1500 Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
1501 so as not to refer to the tables, even though these functions will never be
1502 called when UTF-8 support is disabled. Otherwise there are problems with a
1503 shared library.
1505 10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
1507 (a) It was defining its arguments as char * instead of void *.
1509 (b) It was assuming that all moves were upwards in memory; this was true
1510 a long time ago when I wrote it, but is no longer the case.
1512 The emulated memove() is provided for those environments that have neither
1513 memmove() nor bcopy(). I didn't think anyone used it these days, but that
1514 is clearly not the case, as these two bugs were recently reported.
1516 11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
1517 and Detrail to create the HTML documentation, the .txt form of the man
1518 pages, and it removes trailing spaces from listed files. It also creates
1519 pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
1520 case, it wraps all the #defines with #ifndefs. This script should be run
1521 before "make dist".
1523 12. Fixed two fairly obscure bugs concerned with quantified caseless matching
1524 with Unicode property support.
1526 (a) For a maximizing quantifier, if the two different cases of the
1527 character were of different lengths in their UTF-8 codings (there are
1528 some cases like this - I found 11), and the matching function had to
1529 back up over a mixture of the two cases, it incorrectly assumed they
1530 were both the same length.
1532 (b) When PCRE was configured to use the heap rather than the stack for
1533 recursion during matching, it was not correctly preserving the data for
1534 the other case of a UTF-8 character when checking ahead for a match
1535 while processing a minimizing repeat. If the check also involved
1536 matching a wide character, but failed, corruption could cause an
1537 erroneous result when trying to check for a repeat of the original
1538 character.
1540 13. Some tidying changes to the testing mechanism:
1542 (a) The RunTest script now detects the internal link size and whether there
1543 is UTF-8 and UCP support by running ./pcretest -C instead of relying on
1544 values substituted by "configure". (The RunGrepTest script already did
1545 this for UTF-8.) The configure.ac script no longer substitutes the
1546 relevant variables.
1548 (b) The debugging options /B and /D in pcretest show the compiled bytecode
1549 with length and offset values. This means that the output is different
1550 for different internal link sizes. Test 2 is skipped for link sizes
1551 other than 2 because of this, bypassing the problem. Unfortunately,
1552 there was also a test in test 3 (the locale tests) that used /B and
1553 failed for link sizes other than 2. Rather than cut the whole test out,
1554 I have added a new /Z option to pcretest that replaces the length and
1555 offset values with spaces. This is now used to make test 3 independent
1556 of link size. (Test 2 will be tidied up later.)
1558 14. If erroroffset was passed as NULL to pcre_compile, it provoked a
1559 segmentation fault instead of returning the appropriate error message.
1561 15. In multiline mode when the newline sequence was set to "any", the pattern
1562 ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
1563 This doesn't seem right; it now treats the CRLF combination as the line
1564 ending, and so does not match in that case. It's only a pattern such as ^$
1565 that would hit this one: something like ^ABC$ would have failed after \r
1566 and then tried again after \r\n.
1568 16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
1569 in an attempt to make files that differ only in their line terminators
1570 compare equal. This works on Linux.
1572 17. Under certain error circumstances pcregrep might try to free random memory
1573 as it exited. This is now fixed, thanks to valgrind.
1575 19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
1576 "abc\r\n\r\n", it found an unwanted second match after the second \r. This
1577 was because its rules for how to advance for /g after matching an empty
1578 string at the end of a line did not allow for this case. They now check for
1579 it specially.
1581 20. pcretest is supposed to handle patterns and data of any length, by
1582 extending its buffers when necessary. It was getting this wrong when the
1583 buffer for a data line had to be extended.
1585 21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
1586 CRLF as a newline sequence.
1588 22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
1589 out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
1590 I have nevertheless tidied it up.
1592 23. Added some casts to kill warnings from HP-UX ia64 compiler.
1594 24. Added a man page for pcre-config.
1597 Version 7.0 19-Dec-06
1598 ---------------------
1600 1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
1601 moving to gcc 4.1.1.
1603 2. The -S option for pcretest uses setrlimit(); I had omitted to #include
1604 sys/time.h, which is documented as needed for this function. It doesn't
1605 seem to matter on Linux, but it showed up on some releases of OS X.
1607 3. It seems that there are systems where bytes whose values are greater than
1608 127 match isprint() in the "C" locale. The "C" locale should be the
1609 default when a C program starts up. In most systems, only ASCII printing
1610 characters match isprint(). This difference caused the output from pcretest
1611 to vary, making some of the tests fail. I have changed pcretest so that:
1613 (a) When it is outputting text in the compiled version of a pattern, bytes
1614 other than 32-126 are always shown as hex escapes.
1616 (b) When it is outputting text that is a matched part of a subject string,
1617 it does the same, unless a different locale has been set for the match
1618 (using the /L modifier). In this case, it uses isprint() to decide.
1620 4. Fixed a major bug that caused incorrect computation of the amount of memory
1621 required for a compiled pattern when options that changed within the
1622 pattern affected the logic of the preliminary scan that determines the
1623 length. The relevant options are -x, and -i in UTF-8 mode. The result was
1624 that the computed length was too small. The symptoms of this bug were
1625 either the PCRE error "internal error: code overflow" from pcre_compile(),
1626 or a glibc crash with a message such as "pcretest: free(): invalid next
1627 size (fast)". Examples of patterns that provoked this bug (shown in
1628 pcretest format) are:
1630 /(?-x: )/x
1631 /(?x)(?-x: \s*#\s*)/
1632 /((?i)[\x{c0}])/8
1633 /(?i:[\x{c0}])/8
1635 HOWEVER: Change 17 below makes this fix obsolete as the memory computation
1636 is now done differently.
1638 5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
1639 wrapper classes; (b) implement a new function in the C++ scanner that is
1640 more efficient than the old way of doing things because it avoids levels of
1641 recursion in the regex matching; (c) add a paragraph to the documentation
1642 for the FullMatch() function.
1644 6. The escape sequence \n was being treated as whatever was defined as
1645 "newline". Not only was this contrary to the documentation, which states
1646 that \n is character 10 (hex 0A), but it also went horribly wrong when
1647 "newline" was defined as CRLF. This has been fixed.
1649 7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
1650 was being set to -1 for the "end of line" case (supposedly a value that no
1651 character can have). Though this value is never used (the check for end of
1652 line is "zero bytes in current character"), it caused compiler complaints.
1653 I've changed it to 0xffffffff.
1655 8. In pcre_version.c, the version string was being built by a sequence of
1656 C macros that, in the event of PCRE_PRERELEASE being defined as an empty
1657 string (as it is for production releases) called a macro with an empty
1658 argument. The C standard says the result of this is undefined. The gcc
1659 compiler treats it as an empty string (which was what was wanted) but it is
1660 reported that Visual C gives an error. The source has been hacked around to
1661 avoid this problem.
1663 9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
1664 builds of pcretest, and changed the call to _setmode() to use _O_BINARY
1665 instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
1666 of them did).
1668 10. Originally, pcretest opened its input and output without "b"; then I was
1669 told that "b" was needed in some environments, so it was added for release
1670 5.0 to both the input and output. (It makes no difference on Unix-like
1671 systems.) Later I was told that it is wrong for the input on Windows. I've
1672 now abstracted the modes into two macros, to make it easier to fiddle with
1673 them, and removed "b" from the input mode under Windows.
1675 11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
1677 12. Added -help and --help to pcretest as an official way of being reminded
1678 of the options.
1680 13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
1681 and pcrecpp.cc because they annoy compilers at high warning levels.
1683 14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
1685 15. Fixed an occurrence of == in configure.ac that should have been = (shell
1686 scripts are not C programs :-) and which was not noticed because it works
1687 on Linux.
1689 16. pcretest is supposed to handle any length of pattern and data line (as one
1690 line or as a continued sequence of lines) by extending its input buffer if
1691 necessary. This feature was broken for very long pattern lines, leading to
1692 a string of junk being passed to pcre_compile() if the pattern was longer
1693 than about 50K.
1695 17. I have done a major re-factoring of the way pcre_compile() computes the
1696 amount of memory needed for a compiled pattern. Previously, there was code
1697 that made a preliminary scan of the pattern in order to do this. That was
1698 OK when PCRE was new, but as the facilities have expanded, it has become
1699 harder and harder to keep it in step with the real compile phase, and there
1700 have been a number of bugs (see for example, 4 above). I have now found a
1701 cunning way of running the real compile function in a "fake" mode that
1702 enables it to compute how much memory it would need, while actually only
1703 ever using a few hundred bytes of working memory and without too many
1704 tests of the mode. This should make future maintenance and development
1705 easier. A side effect of this work is that the limit of 200 on the nesting
1706 depth of parentheses has been removed (though this was never a serious
1707 limitation, I suspect). However, there is a downside: pcre_compile() now
1708 runs more slowly than before (30% or more, depending on the pattern). I
1709 hope this isn't a big issue. There is no effect on runtime performance.
1711 18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
1712 newline (only possible for the last line of a file) and it was a
1713 pattern that set a locale (followed by /Lsomething), pcretest crashed.
1715 19. Added additional timing features to pcretest. (1) The -tm option now times
1716 matching only, not compiling. (2) Both -t and -tm can be followed, as a
1717 separate command line item, by a number that specifies the number of
1718 repeats to use when timing. The default is 50000; this gives better
1719 precision, but takes uncomfortably long for very large patterns.
1721 20. Extended pcre_study() to be more clever in cases where a branch of a
1722 subpattern has no definite first character. For example, (a*|b*)[cd] would
1723 previously give no result from pcre_study(). Now it recognizes that the
1724 first character must be a, b, c, or d.
1726 21. There was an incorrect error "recursive call could loop indefinitely" if
1727 a subpattern (or the entire pattern) that was being tested for matching an
1728 empty string contained only one non-empty item after a nested subpattern.
1729 For example, the pattern (?>\x{100}*)\d(?R) provoked this error
1730 incorrectly, because the \d was being skipped in the check.
1732 22. The pcretest program now has a new pattern option /B and a command line
1733 option -b, which is equivalent to adding /B to every pattern. This causes
1734 it to show the compiled bytecode, without the additional information that
1735 -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
1736 is the same as /B/I).
1738 23. A new optimization is now able automatically to treat some sequences such
1739 as a*b as a*+b. More specifically, if something simple (such as a character
1740 or a simple class like \d) has an unlimited quantifier, and is followed by
1741 something that cannot possibly match the quantified thing, the quantifier
1742 is automatically "possessified".
1744 24. A recursive reference to a subpattern whose number was greater than 39
1745 went wrong under certain circumstances in UTF-8 mode. This bug could also
1746 have affected the operation of pcre_study().
1748 25. Realized that a little bit of performance could be had by replacing
1749 (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
1751 26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
1753 27. Possessive quantifiers such as a++ were previously implemented by turning
1754 them into atomic groups such as ($>a+). Now they have their own opcodes,
1755 which improves performance. This includes the automatically created ones
1756 from 23 above.
1758 28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
1759 lookahead was broken if it was not anchored. PCRE was mistakenly expecting
1760 the first matched character to be a colon. This applied both to named and
1761 numbered groups.
1763 29. The ucpinternal.h header file was missing its idempotency #ifdef.
1765 30. I was sent a "project" file called libpcre.a.dev which I understand makes
1766 building PCRE on Windows easier, so I have included it in the distribution.
1768 31. There is now a check in pcretest against a ridiculously large number being
1769 returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
1770 loop, the loop is abandoned.
1772 32. Forward references to subpatterns in conditions such as (?(2)...) where
1773 subpattern 2 is defined later cause pcre_compile() to search forwards in
1774 the pattern for the relevant set of parentheses. This search went wrong
1775 when there were unescaped parentheses in a character class, parentheses
1776 escaped with \Q...\E, or parentheses in a #-comment in /x mode.
1778 33. "Subroutine" calls and backreferences were previously restricted to
1779 referencing subpatterns earlier in the regex. This restriction has now
1780 been removed.
1782 34. Added a number of extra features that are going to be in Perl 5.10. On the
1783 whole, these are just syntactic alternatives for features that PCRE had
1784 previously implemented using the Python syntax or my own invention. The
1785 other formats are all retained for compatibility.
1787 (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
1788 as (?P<name>...). The new forms, as well as being in Perl 5.10, are
1789 also .NET compatible.
1791 (b) A recursion or subroutine call to a named group can now be defined as
1792 (?&name) as well as (?P>name).
1794 (c) A backreference to a named group can now be defined as \k<name> or
1795 \k'name' as well as (?P=name). The new forms, as well as being in Perl
1796 5.10, are also .NET compatible.
1798 (d) A conditional reference to a named group can now use the syntax
1799 (?(<name>) or (?('name') as well as (?(name).
1801 (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
1802 groups (named and numbered) that are never evaluated inline, but can be
1803 called as "subroutines" from elsewhere. In effect, the DEFINE condition
1804 is always false. There may be only one alternative in such a group.
1806 (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
1807 as the simple (?(R). The condition is true only if the most recent
1808 recursion is that of the given number or name. It does not search out
1809 through the entire recursion stack.
1811 (g) The escape \gN or \g{N} has been added, where N is a positive or
1812 negative number, specifying an absolute or relative reference.
1814 35. Tidied to get rid of some further signed/unsigned compiler warnings and
1815 some "unreachable code" warnings.
1817 36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
1818 things, this adds five new scripts.
1820 37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
1821 There were also incompatibilities regarding the handling of \Q..\E inside
1822 character classes, for example with patterns like [\Qa\E-\Qz\E] where the
1823 hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
1825 38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
1826 matches an empty string, and forcibly breaks the loop. There were bugs in
1827 this code in non-simple cases. For a pattern such as ^(a()*)* matched
1828 against aaaa the result was just "a" rather than "aaaa", for example. Two
1829 separate and independent bugs (that affected different cases) have been
1830 fixed.
1832 39. Refactored the code to abolish the use of different opcodes for small
1833 capturing bracket numbers. This is a tidy that I avoided doing when I
1834 removed the limit on the number of capturing brackets for 3.5 back in 2001.
1835 The new approach is not only tidier, it makes it possible to reduce the
1836 memory needed to fix the previous bug (38).
1838 40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
1839 sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
1840 processing dot, circumflex, or dollar metacharacters, or #-comments in /x
1841 mode.
1843 41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
1844 report.
1846 42. Applied patch, originally from Ari Pollak, modified by Google, to allow
1847 copy construction and assignment in the C++ wrapper.
1849 43. Updated pcregrep to support "--newline=any". In the process, I fixed a
1850 couple of bugs that could have given wrong results in the "--newline=crlf"
1851 case.
1853 44. Added a number of casts and did some reorganization of signed/unsigned int
1854 variables following suggestions from Dair Grant. Also renamed the variable
1855 "this" as "item" because it is a C++ keyword.
1857 45. Arranged for dftables to add
1859 #include "pcre_internal.h"
1861 to pcre_chartables.c because without it, gcc 4.x may remove the array
1862 definition from the final binary if PCRE is built into a static library and
1863 dead code stripping is activated.
1865 46. For an unanchored pattern, if a match attempt fails at the start of a
1866 newline sequence, and the newline setting is CRLF or ANY, and the next two
1867 characters are CRLF, advance by two characters instead of one.
1870 Version 6.7 04-Jul-06
1871 ---------------------
1873 1. In order to handle tests when input lines are enormously long, pcretest has
1874 been re-factored so that it automatically extends its buffers when
1875 necessary. The code is crude, but this _is_ just a test program. The
1876 default size has been increased from 32K to 50K.
1878 2. The code in pcre_study() was using the value of the re argument before
1879 testing it for NULL. (Of course, in any sensible call of the function, it
1880 won't be NULL.)
1882 3. The memmove() emulation function in pcre_internal.h, which is used on
1883 systems that lack both memmove() and bcopy() - that is, hardly ever -
1884 was missing a "static" storage class specifier.
1886 4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
1887 containing an extended class (one that cannot be represented by a bitmap
1888 because it contains high-valued characters or Unicode property items, e.g.
1889 [\pZ]). Almost always one would set UTF-8 mode when processing such a
1890 pattern, but PCRE should not loop if you do not (it no longer does).
1891 [Detail: two cases were found: (a) a repeated subpattern containing an
1892 extended class; (b) a recursive reference to a subpattern that followed a
1893 previous extended class. It wasn't skipping over the extended class
1894 correctly when UTF-8 mode was not set.]
1896 5. A negated single-character class was not being recognized as fixed-length
1897 in lookbehind assertions such as (?<=[^f]), leading to an incorrect
1898 compile error "lookbehind assertion is not fixed length".
1900 6. The RunPerlTest auxiliary script was showing an unexpected difference
1901 between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
1902 write a Perl script that can interpret lines of an input file either as
1903 byte characters or as UTF-8, which is what "perltest" was being required to
1904 do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
1905 can't do is switch easily at run time between having the "use utf8;" pragma
1906 or not. In the end, I fudged it by using the RunPerlTest script to insert
1907 "use utf8;" explicitly for the UTF-8 tests.
1909 7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
1910 the end of the subject string, contrary to the documentation and to what
1911 Perl does. This was true of both matching functions. Now it matches only at
1912 the start of the subject and immediately after *internal* newlines.
1914 8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
1915 a pointer to an int instead of a pointer to an unsigned long int. This
1916 caused problems on 64-bit systems.
1918 9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
1919 instance of the 'standard' template library not being so standard".
1921 10. There was no check on the number of named subpatterns nor the maximum
1922 length of a subpattern name. The product of these values is used to compute
1923 the size of the memory block for a compiled pattern. By supplying a very
1924 long subpattern name and a large number of named subpatterns, the size
1925 computation could be caused to overflow. This is now prevented by limiting
1926 the length of names to 32 characters, and the number of named subpatterns
1927 to 10,000.
1929 11. Subpatterns that are repeated with specific counts have to be replicated in
1930 the compiled pattern. The size of memory for this was computed from the
1931 length of the subpattern and the repeat count. The latter is limited to
1932 65535, but there was no limit on the former, meaning that integer overflow
1933 could in principle occur. The compiled length of a repeated subpattern is
1934 now limited to 30,000 bytes in order to prevent this.
1936 12. Added the optional facility to have named substrings with the same name.
1938 13. Added the ability to use a named substring as a condition, using the
1939 Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
1940 are numbers (not recommended). Forward references are permitted.
1942 14. Added forward references in named backreferences (if you see what I mean).
1944 15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
1945 pattern could run off the end of the subject. For example, the pattern
1946 "(?s)(.{1,5})"8 did this with the subject "ab".
1948 16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
1949 PCRE_CASELESS was set when matching characters that were quantified with ?
1950 or *.
1952 17. A character class other than a single negated character that had a minimum
1953 but no maximum quantifier - for example [ab]{6,} - was not handled
1954 correctly by pce_dfa_exec(). It would match only one character.
1956 18. A valid (though odd) pattern that looked like a POSIX character
1957 class but used an invalid character after [ (for example [[,abc,]]) caused
1958 pcre_compile() to give the error "Failed: internal error: code overflow" or
1959 in some cases to crash with a glibc free() error. This could even happen if
1960 the pattern terminated after [[ but there just happened to be a sequence of
1961 letters, a binary zero, and a closing ] in the memory that followed.
1963 19. Perl's treatment of octal escapes in the range \400 to \777 has changed
1964 over the years. Originally (before any Unicode support), just the bottom 8
1965 bits were taken. Thus, for example, \500 really meant \100. Nowadays the
1966 output from "man perlunicode" includes this:
1968 The regular expression compiler produces polymorphic opcodes. That
1969 is, the pattern adapts to the data and automatically switches to
1970 the Unicode character scheme when presented with Unicode data--or
1971 instead uses a traditional byte scheme when presented with byte
1972 data.
1974 Sadly, a wide octal escape does not cause a switch, and in a string with
1975 no other multibyte characters, these octal escapes are treated as before.
1976 Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern
1977 /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
1978 Unicode string.
1980 I have not perpetrated such confusion in PCRE. Up till now, it took just
1981 the bottom 8 bits, as in old Perl. I have now made octal escapes with
1982 values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
1983 translate to the appropriate multibyte character.
1985 29. Applied some refactoring to reduce the number of warnings from Microsoft
1986 and Borland compilers. This has included removing the fudge introduced
1987 seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
1988 a warning about an unused variable.
1990 21. PCRE has not included VT (character 0x0b) in the set of whitespace
1991 characters since release 4.0, because Perl (from release 5.004) does not.
1992 [Or at least, is documented not to: some releases seem to be in conflict
1993 with the documentation.] However, when a pattern was studied with
1994 pcre_study() and all its branches started with \s, PCRE still included VT
1995 as a possible starting character. Of course, this did no harm; it just
1996 caused an unnecessary match attempt.
1998 22. Removed a now-redundant internal flag bit that recorded the fact that case
1999 dependency changed within the pattern. This was once needed for "required
2000 byte" processing, but is no longer used. This recovers a now-scarce options
2001 bit. Also moved the least significant internal flag bit to the most-
2002 significant bit of the word, which was not previously used (hangover from
2003 the days when it was an int rather than a uint) to free up another bit for
2004 the future.
2006 23. Added support for CRLF line endings as well as CR and LF. As well as the
2007 default being selectable at build time, it can now be changed at runtime
2008 via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
2009 specify that it is scanning data with non-default line endings.
2011 24. Changed the definition of CXXLINK to make it agree with the definition of
2012 LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
2014 25. Applied Ian Taylor's patches to avoid using another stack frame for tail
2015 recursions. This makes a big different to stack usage for some patterns.
2017 26. If a subpattern containing a named recursion or subroutine reference such
2018 as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
2019 the space required for the compiled pattern went wrong and gave too small a
2020 value. Depending on the environment, this could lead to "Failed: internal
2021 error: code overflow at offset 49" or "glibc detected double free or
2022 corruption" errors.
2024 27. Applied patches from Google (a) to support the new newline modes and (b) to
2025 advance over multibyte UTF-8 characters in GlobalReplace.
2027 28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
2028 difference for some implementation of PCRE in some Windows version.
2030 29. Added some extra testing facilities to pcretest:
2032 \q<number> in a data line sets the "match limit" value
2033 \Q<number> in a data line sets the "match recursion limt" value
2034 -S <number> sets the stack size, where <number> is in megabytes
2036 The -S option isn't available for Windows.
2039 Version 6.6 06-Feb-06
2040 ---------------------
2042 1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
2043 in pcreposix.h. I have copied the definition from pcre.h.
2045 2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
2046 because pcre.h is no longer a built file.
2048 3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
2049 not normally included in the compiled code.
2052 Version 6.5 01-Feb-06
2053 ---------------------
2055 1. When using the partial match feature with pcre_dfa_exec(), it was not
2056 anchoring the second and subsequent partial matches at the new starting
2057 point. This could lead to incorrect results. For example, with the pattern
2058 /1234/, partially matching against "123" and then "a4" gave a match.
2060 2. Changes to pcregrep:
2062 (a) All non-match returns from pcre_exec() were being treated as failures
2063 to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
2064 error message is output. Some extra information is given for the
2066 probably the only errors that are likely to be caused by users (by
2067 specifying a regex that has nested indefinite repeats, for instance).
2068 If there are more than 20 of these errors, pcregrep is abandoned.
2070 (b) A binary zero was treated as data while matching, but terminated the
2071 output line if it was written out. This has been fixed: binary zeroes
2072 are now no different to any other data bytes.
2074 (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
2075 used to set a locale for matching. The --locale=xxxx long option has
2076 been added (no short equivalent) to specify a locale explicitly on the
2077 pcregrep command, overriding the environment variables.
2079 (d) When -B was used with -n, some line numbers in the output were one less
2080 than they should have been.
2082 (e) Added the -o (--only-matching) option.
2084 (f) If -A or -C was used with -c (count only), some lines of context were
2085 accidentally printed for the final match.
2087 (g) Added the -H (--with-filename) option.
2089 (h) The combination of options -rh failed to suppress file names for files
2090 that were found from directory arguments.
2092 (i) Added the -D (--devices) and -d (--directories) options.
2094 (j) Added the -F (--fixed-strings) option.
2096 (k) Allow "-" to be used as a file name for -f as well as for a data file.
2098 (l) Added the --colo(u)r option.
2100 (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
2101 is not present by default.
2103 3. A nasty bug was discovered in the handling of recursive patterns, that is,
2104 items such as (?R) or (?1), when the recursion could match a number of
2105 alternatives. If it matched one of the alternatives, but subsequently,
2106 outside the recursion, there was a failure, the code tried to back up into
2107 the recursion. However, because of the way PCRE is implemented, this is not
2108 possible, and the result was an incorrect result from the match.
2110 In order to prevent this happening, the specification of recursion has
2111 been changed so that all such subpatterns are automatically treated as
2112 atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
2114 4. I had overlooked the fact that, in some locales, there are characters for
2115 which isalpha() is true but neither isupper() nor islower() are true. In
2116 the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
2117 and ordfeminine) are like this. This affected the treatment of \w and \W
2118 when they appeared in character classes, but not when they appeared outside
2119 a character class. The bit map for "word" characters is now created
2120 separately from the results of isalnum() instead of just taking it from the
2121 upper, lower, and digit maps. (Plus the underscore character, of course.)
2123 5. The above bug also affected the handling of POSIX character classes such as
2124 [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
2125 permanent tables. Instead, the bit maps for such a class were previously
2126 created as the appropriate unions of the upper, lower, and digit bitmaps.
2127 Now they are created by subtraction from the [[:word:]] class, which has
2128 its own bitmap.
2130 6. The [[:blank:]] character class matches horizontal, but not vertical space.
2131 It is created by subtracting the vertical space characters (\x09, \x0a,
2132 \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
2133 subtraction was done in the overall bitmap for a character class, meaning
2134 that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
2135 be recognized. This bug has been fixed.
2137 7. Patches from the folks at Google:
2139 (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
2140 real life, but is still worth protecting against".
2142 (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
2143 regular expressions".
2145 (c) pcre_scanner.cc: avoid use of std::count() because not all systems
2146 have it.
2148 (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
2149 "configure" and the latter not, in order to fix a problem somebody had
2150 with compiling the Arg class on HP-UX.
2152 (e) Improve the error-handling of the C++ wrapper a little bit.
2154 (f) New tests for checking recursion limiting.
2156 8. The pcre_memmove() function, which is used only if the environment does not
2157 have a standard memmove() function (and is therefore rarely compiled),
2158 contained two bugs: (a) use of int instead of size_t, and (b) it was not
2159 returning a result (though PCRE never actually uses the result).
2161 9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
2162 large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
2163 returned instead of calling malloc() with an overflowing number that would
2164 most likely cause subsequent chaos.
2166 10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
2168 11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
2169 with this option is matched, the nmatch and pmatch options of regexec() are
2170 ignored.
2172 12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
2173 provided in case anyone wants to the the POSIX interface with UTF-8
2174 strings.
2176 13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
2177 C++ linking (needed for some HP-UX environments).
2179 14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
2180 (unused parameter) and in the pcre_printint() function (omitted "default"
2181 switch label when the default is to do nothing).
2183 15. Added some code to make it possible, when PCRE is compiled as a C++
2184 library, to replace subject pointers for pcre_exec() with a smart pointer
2185 class, thus making it possible to process discontinuous strings.
2187 16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
2188 much the same function. They were added by different people who were trying
2189 to make PCRE easy to compile on non-Unix systems. It has been suggested
2190 that PCRE_EXPORT be abolished now that there is more automatic apparatus
2191 for compiling on Windows systems. I have therefore replaced it with
2192 PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
2193 defaults to "extern" for C or "extern C" for C++, which works fine on
2194 Unix-like systems. It is now possible to override the value of PCRE_DATA_
2195 SCOPE with something explicit in config.h. In addition:
2197 (a) pcreposix.h still had just "extern" instead of either of these macros;
2198 I have replaced it with PCRE_DATA_SCOPE.
2200 (b) Functions such as _pcre_xclass(), which are internal to the library,
2201 but external in the C sense, all had PCRE_EXPORT in their definitions.
2202 This is apparently wrong for the Windows case, so I have removed it.
2203 (It makes no difference on Unix-like systems.)
2205 17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
2206 of recursive calls to match(). This is different to MATCH_LIMIT because
2207 that limits the total number of calls to match(), not all of which increase
2208 the depth of recursion. Limiting the recursion depth limits the amount of
2209 stack (or heap if NO_RECURSE is set) that is used. The default can be set
2210 when PCRE is compiled, and changed at run time. A patch from Google adds
2211 this functionality to the C++ interface.
2213 18. Changes to the handling of Unicode character properties:
2215 (a) Updated the table to Unicode 4.1.0.
2217 (b) Recognize characters that are not in the table as "Cn" (undefined).
2219 (c) I revised the way the table is implemented to a much improved format
2220 which includes recognition of ranges. It now supports the ranges that
2221 are defined in UnicodeData.txt, and it also amalgamates other
2222 characters into ranges. This has reduced the number of entries in the
2223 table from around 16,000 to around 3,000, thus reducing its size
2224 considerably. I realized I did not need to use a tree structure after
2225 all - a binary chop search is just as efficient. Having reduced the
2226 number of entries, I extended their size from 6 bytes to 8 bytes to
2227 allow for more data.
2229 (d) Added support for Unicode script names via properties such as \p{Han}.
2231 19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
2232 matching that character.
2234 20. When matching a repeated Unicode property with a minimum greater than zero,
2235 (for example \pL{2,}), PCRE could look past the end of the subject if it
2236 reached it while seeking the minimum number of characters. This could
2237 happen only if some of the characters were more than one byte long, because
2238 there is a check for at least the minimum number of bytes.
2240 21. Refactored the implementation of \p and \P so as to be more general, to
2241 allow for more different types of property in future. This has changed the
2242 compiled form incompatibly. Anybody with saved compiled patterns that use
2243 \p or \P will have to recompile them.
2245 22. Added "Any" and "L&" to the supported property types.
2247 23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
2248 but give a compile time error if the value is greater than 0xff.
2250 24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
2251 accidentally not being installed or uninstalled.
2253 25. The pcre.h file was built from pcre.h.in, but the only changes that were
2254 made were to insert the current release number. This seemed silly, because
2255 it made things harder for people building PCRE on systems that don't run
2256 "configure". I have turned pcre.h into a distributed file, no longer built
2257 by "configure", with the version identification directly included. There is
2258 no longer a pcre.h.in file.
2260 However, this change necessitated a change to the pcre-config script as
2261 well. It is built from pcre-config.in, and one of the substitutions was the
2262 release number. I have updated configure.ac so that ./configure now finds
2263 the release number by grepping pcre.h.
2265 26. Added the ability to run the tests under valgrind.
2268 Version 6.4 05-Sep-05
2269 ---------------------
2271 1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
2272 "--" to be printed when multiple files were scanned, even when none of the
2273 -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
2274 consider it to be a bug, and have restored the previous behaviour.
2276 2. A couple of code tidies to get rid of compiler warnings.
2278 3. The pcretest program used to cheat by referring to symbols in the library
2279 whose names begin with _pcre_. These are internal symbols that are not
2280 really supposed to be visible externally, and in some environments it is
2281 possible to suppress them. The cheating is now confined to including
2282 certain files from the library's source, which is a bit cleaner.
2284 4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
2285 file's purpose clearer.
2287 5. Reorganized pcre_ucp_findchar().
2290 Version 6.3 15-Aug-05
2291 ---------------------
2293 1. The file libpcre.pc.in did not have general read permission in the tarball.
2295 2. There were some problems when building without C++ support:
2297 (a) If C++ support was not built, "make install" and "make test" still
2298 tried to test it.
2300 (b) There were problems when the value of CXX was explicitly set. Some
2301 changes have been made to try to fix these, and ...
2303 (c) --disable-cpp can now be used to explicitly disable C++ support.
2305 (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
2306 backslash in a target when C++ was disabled. This confuses some
2307 versions of "make", apparently. Using an intermediate variable solves
2308 this. (Same for CPP_LOBJ.)
2310 3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
2311 (non-Windows) now includes $(CFLAGS) because these flags are sometimes
2312 necessary on certain architectures.
2314 4. Added a setting of -export-symbols-regex to the link command to remove
2315 those symbols that are exported in the C sense, but actually are local
2316 within the library, and not documented. Their names all begin with
2317 "_pcre_". This is not a perfect job, because (a) we have to except some
2318 symbols that pcretest ("illegally") uses, and (b) the facility isn't always
2319 available (and never for static libraries). I have made a note to try to
2320 find a way round (a) in the future.
2323 Version 6.2 01-Aug-05
2324 ---------------------
2326 1. There was no test for integer overflow of quantifier values. A construction
2327 such as {1111111111111111} would give undefined results. What is worse, if
2328 a minimum quantifier for a parenthesized subpattern overflowed and became
2329 negative, the calculation of the memory size went wrong. This could have
2330 led to memory overwriting.
2332 2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
2334 3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
2335 operating environments where this matters.
2337 4. Applied Giuseppe Maxia's patch to add additional features for controlling
2338 PCRE options from within the C++ wrapper.
2340 5. Named capturing subpatterns were not being correctly counted when a pattern
2341 was compiled. This caused two problems: (a) If there were more than 100
2342 such subpatterns, the calculation of the memory needed for the whole
2343 compiled pattern went wrong, leading to an overflow error. (b) Numerical
2344 back references of the form \12, where the number was greater than 9, were
2345 not recognized as back references, even though there were sufficient
2346 previous subpatterns.
2348 6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
2349 versions of gcc, e.g. 2.95.4.
2352 Version 6.1 21-Jun-05
2353 ---------------------
2355 1. There was one reference to the variable "posix" in pcretest.c that was not
2356 surrounded by "#if !defined NOPOSIX".
2358 2. Make it possible to compile pcretest without DFA support, UTF8 support, or
2359 the cross-check on the old pcre_info() function, for the benefit of the
2360 cut-down version of PCRE that is currently imported into Exim.
2362 3. A (silly) pattern starting with (?i)(?-i) caused an internal space
2363 allocation error. I've done the easy fix, which wastes 2 bytes for sensible
2364 patterns that start (?i) but I don't think that matters. The use of (?i) is
2365 just an example; this all applies to the other options as well.
2367 4. Since libtool seems to echo the compile commands it is issuing, the output
2368 from "make" can be reduced a bit by putting "@" in front of each libtool
2369 compile command.
2371 5. Patch from the folks at Google for configure.in to be a bit more thorough
2372 in checking for a suitable C++ installation before trying to compile the
2373 C++ stuff. This should fix a reported problem when a compiler was present,
2374 but no suitable headers.
2376 6. The man pages all had just "PCRE" as their title. I have changed them to
2377 be the relevant file name. I have also arranged that these names are
2378 retained in the file doc/pcre.txt, which is a concatenation in text format
2379 of all the man pages except the little individual ones for each function.
2381 7. The NON-UNIX-USE file had not been updated for the different set of source
2382 files that come with release 6. I also added a few comments about the C++
2383 wrapper.
2386 Version 6.0 07-Jun-05
2387 ---------------------
2389 1. Some minor internal re-organization to help with my DFA experiments.
2391 2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
2392 didn't matter for the library itself when fully configured, but did matter
2393 when compiling without UCP support, or within Exim, where the ucp files are
2394 not imported.
2396 3. Refactoring of the library code to split up the various functions into
2397 different source modules. The addition of the new DFA matching code (see
2398 below) to a single monolithic source would have made it really too
2399 unwieldy, quite apart from causing all the code to be include in a
2400 statically linked application, when only some functions are used. This is
2401 relevant even without the DFA addition now that patterns can be compiled in
2402 one application and matched in another.
2404 The downside of splitting up is that there have to be some external
2405 functions and data tables that are used internally in different modules of
2406 the library but which are not part of the API. These have all had their
2407 names changed to start with "_pcre_" so that they are unlikely to clash
2408 with other external names.
2410 4. Added an alternate matching function, pcre_dfa_exec(), which matches using
2411 a different (DFA) algorithm. Although it is slower than the original
2412 function, it does have some advantages for certain types of matching
2413 problem.
2415 5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
2416 including restarting after a partial match.
2418 6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
2419 defined when compiling for Windows was sent to me. I have put it into the
2420 code, though I have no means of testing or verifying it.
2422 7. Added the pcre_refcount() auxiliary function.
2424 8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
2425 match before or at the first newline in the subject string. In pcretest,
2426 the /f option on a pattern can be used to set this.
2428 9. A repeated \w when used in UTF-8 mode with characters greater than 256
2429 would behave wrongly. This has been present in PCRE since release 4.0.
2431 10. A number of changes to the pcregrep command:
2433 (a) Refactored how -x works; insert ^(...)$ instead of setting
2434 PCRE_ANCHORED and checking the length, in preparation for adding
2435 something similar for -w.
2437 (b) Added the -w (match as a word) option.
2439 (c) Refactored the way lines are read and buffered so as to have more
2440 than one at a time available.
2442 (d) Implemented a pcregrep test script.
2444 (e) Added the -M (multiline match) option. This allows patterns to match
2445 over several lines of the subject. The buffering ensures that at least
2446 8K, or the rest of the document (whichever is the shorter) is available
2447 for matching (and similarly the previous 8K for lookbehind assertions).
2449 (f) Changed the --help output so that it now says
2451 -w, --word-regex(p)
2453 instead of two lines, one with "regex" and the other with "regexp"
2454 because that confused at least one person since the short forms are the
2455 same. (This required a bit of code, as the output is generated
2456 automatically from a table. It wasn't just a text change.)
2458 (g) -- can be used to terminate pcregrep options if the next thing isn't an
2459 option but starts with a hyphen. Could be a pattern or a path name
2460 starting with a hyphen, for instance.
2462 (h) "-" can be given as a file name to represent stdin.
2464 (i) When file names are being printed, "(standard input)" is used for
2465 the standard input, for compatibility with GNU grep. Previously
2466 "<stdin>" was used.
2468 (j) The option --label=xxx can be used to supply a name to be used for
2469 stdin when file names are being printed. There is no short form.
2471 (k) Re-factored the options decoding logic because we are going to add
2472 two more options that take data. Such options can now be given in four
2473 different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
2475 (l) Added the -A, -B, and -C options for requesting that lines of context
2476 around matches be printed.
2478 (m) Added the -L option to print the names of files that do not contain
2479 any matching lines, that is, the complement of -l.
2481 (n) The return code is 2 if any file cannot be opened, but pcregrep does
2482 continue to scan other files.
2484 (o) The -s option was incorrectly implemented. For compatibility with other
2485 greps, it now suppresses the error message for a non-existent or non-
2486 accessible file (but not the return code). There is a new option called
2487 -q that suppresses the output of matching lines, which was what -s was
2488 previously doing.
2490 (p) Added --include and --exclude options to specify files for inclusion
2491 and exclusion when recursing.
2493 11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
2494 Hopefully, it now does.
2496 12. Missing cast in pcre_study().
2498 13. Added an "uninstall" target to the makefile.
2500 14. Replaced "extern" in the function prototypes in Makefile.in with
2501 "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
2502 world, but is set differently for Windows.
2504 15. Added a second compiling function called pcre_compile2(). The only
2505 difference is that it has an extra argument, which is a pointer to an
2506 integer error code. When there is a compile-time failure, this is set
2507 non-zero, in addition to the error test pointer being set to point to an
2508 error message. The new argument may be NULL if no error number is required
2509 (but then you may as well call pcre_compile(), which is now just a
2510 wrapper). This facility is provided because some applications need a
2511 numeric error indication, but it has also enabled me to tidy up the way
2512 compile-time errors are handled in the POSIX wrapper.
2514 16. Added VPATH=.libs to the makefile; this should help when building with one
2515 prefix path and installing with another. (Or so I'm told by someone who
2516 knows more about this stuff than I do.)
2518 17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
2519 passes PCRE_DOTALL to the pcre_compile() function, making the "." character
2520 match everything, including newlines. This is not POSIX-compatible, but
2521 somebody wanted the feature. From pcretest it can be activated by using
2522 both the P and the s flags.
2524 18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
2526 19. libpcre.pc was being incorrectly installed as executable.
2528 20. A couple of places in pcretest check for end-of-line by looking for '\n';
2529 it now also looks for '\r' so that it will work unmodified on Windows.
2531 21. Added Google's contributed C++ wrapper to the distribution.
2533 22. Added some untidy missing memory free() calls in pcretest, to keep
2534 Electric Fence happy when testing.
2538 Version 5.0 13-Sep-04
2539 ---------------------
2541 1. Internal change: literal characters are no longer packed up into items
2542 containing multiple characters in a single byte-string. Each character
2543 is now matched using a separate opcode. However, there may be more than one
2544 byte in the character in UTF-8 mode.
2546 2. The pcre_callout_block structure has two new fields: pattern_position and
2547 next_item_length. These contain the offset in the pattern to the next match
2548 item, and its length, respectively.
2550 3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
2551 insertion of callouts before each pattern item. Added the /C option to
2552 pcretest to make use of this.
2554 4. On the advice of a Windows user, the lines
2556 #if defined(_WIN32) || defined(WIN32)
2557 _setmode( _fileno( stdout ), 0x8000 );
2558 #endif /* defined(_WIN32) || defined(WIN32) */
2560 have been added to the source of pcretest. This apparently does useful
2561 magic in relation to line terminators.
2563 5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
2564 for the benefit of those environments where the "b" makes a difference.
2566 6. The icc compiler has the same options as gcc, but "configure" doesn't seem
2567 to know about it. I have put a hack into configure.in that adds in code
2568 to set GCC=yes if CC=icc. This seems to end up at a point in the
2569 generated configure script that is early enough to affect the setting of
2570 compiler options, which is what is needed, but I have no means of testing
2571 whether it really works. (The user who reported this had patched the
2572 generated configure script, which of course I cannot do.)
2574 LATER: After change 22 below (new libtool files), the configure script
2575 seems to know about icc (and also ecc). Therefore, I have commented out
2576 this hack in configure.in.
2578 7. Added support for pkg-config (2 patches were sent in).
2580 8. Negated POSIX character classes that used a combination of internal tables
2581 were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
2582 [[:^ascii]]. Typically, they would match almost any characters. The other
2583 POSIX classes were not broken in this way.
2585 9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
2586 to find the match, as PCRE was deluded into thinking that the match had to
2587 start at the start point or following a newline. The same bug applied to
2588 patterns with negative forward assertions or any backward assertions
2589 preceding ".*" at the start, unless the pattern required a fixed first
2590 character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
2592 10. In UTF-8 mode, when moving forwards in the subject after a failed match
2593 starting at the last subject character, bytes beyond the end of the subject
2594 string were read.
2596 11. Renamed the variable "class" as "classbits" to make life easier for C++
2597 users. (Previously there was a macro definition, but it apparently wasn't
2598 enough.)
2600 12. Added the new field "tables" to the extra data so that tables can be passed
2601 in at exec time, or the internal tables can be re-selected. This allows
2602 a compiled regex to be saved and re-used at a later time by a different
2603 program that might have everything at different addresses.
2605 13. Modified the pcre-config script so that, when run on Solaris, it shows a
2606 -R library as well as a -L library.
2608 14. The debugging options of pcretest (-d on the command line or D on a
2609 pattern) showed incorrect output for anything following an extended class
2610 that contained multibyte characters and which was followed by a quantifier.
2612 15. Added optional support for general category Unicode character properties
2613 via the \p, \P, and \X escapes. Unicode property support implies UTF-8
2614 support. It adds about 90K to the size of the library. The meanings of the
2615 inbuilt class escapes such as \d and \s have NOT been changed.
2617 16. Updated pcredemo.c to include calls to free() to release the memory for the
2618 compiled pattern.
2620 17. The generated file chartables.c was being created in the source directory
2621 instead of in the building directory. This caused the build to fail if the
2622 source directory was different from the building directory, and was
2623 read-only.
2625 18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
2626 file. No doubt somebody will tell me if they don't make sense... Also added
2627 Dan Mooney's comments about building on OpenVMS.
2629 19. Added support for partial matching via the PCRE_PARTIAL option for
2630 pcre_exec() and the \P data escape in pcretest.
2632 20. Extended pcretest with 3 new pattern features:
2634 (i) A pattern option of the form ">rest-of-line" causes pcretest to
2635 write the compiled pattern to the file whose name is "rest-of-line".
2636 This is a straight binary dump of the data, with the saved pointer to
2637 the character tables forced to be NULL. The study data, if any, is
2638 written too. After writing, pcretest reads a new pattern.
2640 (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
2641 compiled pattern from the given file. There must not be any
2642 occurrences of "<" in the file name (pretty unlikely); if there are,
2643 pcretest will instead treat the initial "<" as a pattern delimiter.
2644 After reading in the pattern, pcretest goes on to read data lines as
2645 usual.
2647 (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
2648 and 16-bit fields in a compiled pattern, to simulate a pattern that
2649 was compiled on a host of opposite endianness.
2651 21. The pcre-exec() function can now cope with patterns that were compiled on
2652 hosts of opposite endianness, with this restriction:
2654 As for any compiled expression that is saved and used later, the tables
2655 pointer field cannot be preserved; the extra_data field in the arguments
2656 to pcre_exec() should be used to pass in a tables address if a value
2657 other than the default internal tables were used at compile time.
2659 22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
2660 now diagnosed as an error. Previously, most of the time, a negative number
2661 would have been treated as zero, but if in addition "ovector" was passed as
2662 NULL, a crash could occur.
2664 23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
2665 new versions from the libtool 1.5 distribution (the last one is a copy of
2666 a file called libtool.m4). This seems to have fixed the need to patch
2667 "configure" to support Darwin 1.3 (which I used to do). However, I still
2668 had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
2669 workstation).
2671 24. Changed the PCRE licence to be the more standard "BSD" licence.
2674 Version 4.5 01-Dec-03
2675 ---------------------
2677 1. There has been some re-arrangement of the code for the match() function so
2678 that it can be compiled in a version that does not call itself recursively.
2679 Instead, it keeps those local variables that need separate instances for
2680 each "recursion" in a frame on the heap, and gets/frees frames whenever it
2681 needs to "recurse". Keeping track of where control must go is done by means
2682 of setjmp/longjmp. The whole thing is implemented by a set of macros that
2683 hide most of the details from the main code, and operates only if
2684 NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
2685 "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
2686 operating.
2688 To make it easier for callers to provide specially tailored get/free
2689 functions for this usage, two new functions, pcre_stack_malloc, and
2690 pcre_stack_free, are used. They are always called in strict stacking order,
2691 and the size of block requested is always the same.
2693 The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
2694 PCRE has been compiled to use the stack or the heap for recursion. The
2695 -C option of pcretest uses this to show which version is compiled.
2697 A new data escape \S, is added to pcretest; it causes the amounts of store
2698 obtained and freed by both kinds of malloc/free at match time to be added
2699 to the output.
2701 2. Changed the locale test to use "fr_FR" instead of "fr" because that's
2702 what's available on my current Linux desktop machine.
2704 3. When matching a UTF-8 string, the test for a valid string at the start has
2705 been extended. If start_offset is not zero, PCRE now checks that it points
2706 to a byte that is the start of a UTF-8 character. If not, it returns
2707 PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
2708 this is necessary because there may be backward assertions in the pattern.
2709 When matching the same subject several times, it may save resources to use
2710 PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
2712 4. The code for checking the validity of UTF-8 strings has been tightened so
2713 that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
2714 containing "overlong sequences".
2716 5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
2717 I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
2718 should have been "&", but it just so happened that all the cases this let
2719 through by mistake were picked up later in the function.
2721 6. I had used a variable called "isblank" - this is a C99 function, causing
2722 some compilers to warn. To avoid this, I renamed it (as "blankclass").
2724 7. Cosmetic: (a) only output another newline at the end of pcretest if it is
2725 prompting; (b) run "./pcretest /dev/null" at the start of the test script
2726 so the version is shown; (c) stop "make test" echoing "./RunTest".
2728 8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
2730 9. The prototype for memmove() for systems that don't have it was using
2731 size_t, but the inclusion of the header that defines size_t was later. I've
2732 moved the #includes for the C headers earlier to avoid this.
2734 10. Added some adjustments to the code to make it easier to compiler on certain
2735 special systems:
2737 (a) Some "const" qualifiers were missing.
2738 (b) Added the macro EXPORT before all exported functions; by default this
2739 is defined to be empty.
2740 (c) Changed the dftables auxiliary program (that builds chartables.c) so
2741 that it reads its output file name as an argument instead of writing
2742 to the standard output and assuming this can be redirected.
2744 11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
2745 class containing characters with values greater than 255, PCRE compilation
2746 went into a loop.
2748 12. A recursive reference to a subpattern that was within another subpattern
2749 that had a minimum quantifier of zero caused PCRE to crash. For example,
2750 (x(y(?2))z)? provoked this bug with a subject that got as far as the
2751 recursion. If the recursively-called subpattern itself had a zero repeat,
2752 that was OK.
2754 13. In pcretest, the buffer for reading a data line was set at 30K, but the
2755 buffer into which it was copied (for escape processing) was still set at
2756 1024, so long lines caused crashes.
2758 14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
2759 "internal error: code overflow...". This applied to any character class
2760 that was followed by a possessive quantifier.
2762 15. Modified the Makefile to add libpcre.la as a prerequisite for
2763 libpcreposix.la because I was told this is needed for a parallel build to
2764 work.
2766 16. If a pattern that contained .* following optional items at the start was
2767 studied, the wrong optimizing data was generated, leading to matching
2768 errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
2769 matching string must start with a or b or c. The correct conclusion for
2770 this pattern is that a match can start with any character.
2773 Version 4.4 13-Aug-03
2774 ---------------------
2776 1. In UTF-8 mode, a character class containing characters with values between
2777 127 and 255 was not handled correctly if the compiled pattern was studied.
2778 In fixing this, I have also improved the studying algorithm for such
2779 classes (slightly).
2781 2. Three internal functions had redundant arguments passed to them. Removal
2782 might give a very teeny performance improvement.
2784 3. Documentation bug: the value of the capture_top field in a callout is *one
2785 more than* the number of the hightest numbered captured substring.
2787 4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
2788 in incorrectly linking with a previously installed version. They now link
2789 explicitly with libpcre.la.
2791 5. configure.in no longer needs to recognize Cygwin specially.
2793 6. A problem in pcre.in for Windows platforms is fixed.
2795 7. If a pattern was successfully studied, and the -d (or /D) flag was given to
2796 pcretest, it used to include the size of the study block as part of its
2797 output. Unfortunately, the structure contains a field that has a different
2798 size on different hardware architectures. This meant that the tests that
2799 showed this size failed. As the block is currently always of a fixed size,
2800 this information isn't actually particularly useful in pcretest output, so
2801 I have just removed it.
2803 8. Three pre-processor statements accidentally did not start in column 1.
2804 Sadly, there are *still* compilers around that complain, even though
2805 standard C has not required this for well over a decade. Sigh.
2807 9. In pcretest, the code for checking callouts passed small integers in the
2808 callout_data field, which is a void * field. However, some picky compilers
2809 complained about the casts involved for this on 64-bit systems. Now
2810 pcretest passes the address of the small integer instead, which should get
2811 rid of the warnings.
2813 10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
2814 both compile and run time, and gives an error if an invalid UTF-8 sequence
2815 is found. There is a option for disabling this check in cases where the
2816 string is known to be correct and/or the maximum performance is wanted.
2818 11. In response to a bug report, I changed one line in Makefile.in from
2820 -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
2821 to
2822 -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
2824 to look similar to other lines, but I have no way of telling whether this
2825 is the right thing to do, as I do not use Windows. No doubt I'll get told
2826 if it's wrong...
2829 Version 4.3 21-May-03
2830 ---------------------
2832 1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
2833 Makefile.
2835 2. Some refactoring to improve the quality of the code:
2837 (i) The utf8_table... variables are now declared "const".
2839 (ii) The code for \cx, which used the "case flipping" table to upper case
2840 lower case letters, now just substracts 32. This is ASCII-specific,
2841 but the whole concept of \cx is ASCII-specific, so it seems
2842 reasonable.
2844 (iii) PCRE was using its character types table to recognize decimal and
2845 hexadecimal digits in the pattern. This is silly, because it handles
2846 only 0-9, a-f, and A-F, but the character types table is locale-
2847 specific, which means strange things might happen. A private
2848 table is now used for this - though it costs 256 bytes, a table is
2849 much faster than multiple explicit tests. Of course, the standard
2850 character types table is still used for matching digits in subject
2851 strings against \d.
2853 (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
2854 ending in _t are). So I've renamed it as ESC_tee.
2856 3. The first argument for regexec() in the POSIX wrapper should have been
2857 defined as "const".
2859 4. Changed pcretest to use malloc() for its buffers so that they can be
2860 Electric Fenced for debugging.
2862 5. There were several places in the code where, in UTF-8 mode, PCRE would try
2863 to read one or more bytes before the start of the subject string. Often this
2864 had no effect on PCRE's behaviour, but in some circumstances it could
2865 provoke a segmentation fault.
2867 6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
2868 to try to read one or more bytes before the start of the subject string.
2870 7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
2871 UTF-8 support could misbehave in various ways if the subject string
2872 contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
2873 area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
2874 back over UTF-8 characters.)
2877 Version 4.2 14-Apr-03
2878 ---------------------
2880 1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
2882 2. Changes to the building process, supplied by Ronald Landheer-Cieslak
2883 [ON_WINDOWS]: new variable, "#" on non-Windows platforms
2884 [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
2885 [WIN_PREFIX]: new variable, "cyg" for Cygwin
2886 * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
2888 Note: automatic setting of the BUILD variables is not yet working
2889 set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
2890 compile-time but not at link-time
2891 [LINK]: use for linking executables only
2892 make different versions for Windows and non-Windows
2893 [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
2894 libraries
2895 [LINK_FOR_BUILD]: new variable
2896 [OBJEXT]: use throughout
2897 [EXEEXT]: use throughout
2898 <winshared>: new target
2899 <wininstall>: new target
2900 <dftables.o>: use native compiler
2901 <dftables>: use native linker
2902 <install>: handle Windows platform correctly
2903 <clean>: ditto
2904 <check>: ditto
2905 copy DLL to top builddir before testing
2907 As part of these changes, -no-undefined was removed again. This was reported
2908 to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
2909 in any case.
2911 3. Some tidies to get rid of compiler warnings:
2913 . In the match_data structure, match_limit was an unsigned long int, whereas
2914 match_call_count was an int. I've made them both unsigned long ints.
2916 . In pcretest the fact that a const uschar * doesn't automatically cast to
2917 a void * provoked a warning.
2919 . Turning on some more compiler warnings threw up some "shadow" variables
2920 and a few more missing casts.
2922 4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
2923 option, a class that contained a single character with a value between 128
2924 and 255 (e.g. /[\xFF]/) caused PCRE to crash.
2926 5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
2927 option, a class that contained several characters, but with at least one
2928 whose value was between 128 and 255 caused PCRE to crash.
2931 Version 4.1 12-Mar-03
2932 ---------------------
2934 1. Compiling with gcc -pedantic found a couple of places where casts were
2935 needed, and a string in dftables.c that was longer than standard compilers are
2936 required to support.
2938 2. Compiling with Sun's compiler found a few more places where the code could
2939 be tidied up in order to avoid warnings.
2941 3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
2942 first of these names is deprecated in the latest Autoconf in favour of the name
2943 CC_FOR_BUILD, because "host" is typically used to mean the system on which the
2944 compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
2945 analogy I have changed it to CFLAGS_FOR_BUILD.
2947 4. Added -no-undefined to the linking command in the Makefile, because this is
2948 apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
2949 linking step for the pcreposix library.
2951 5. PCRE was failing to diagnose the case of two named groups with the same
2952 name.
2954 6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
2955 literal character that is needed in the subject for a match, and scans along to
2956 ensure that it is present before embarking on the full matching process. This
2957 saves time in cases of nested unlimited repeats that are never going to match.
2958 Problem: the scan can take a lot of time if the subject is very long (e.g.
2959 megabytes), thus penalizing straightforward matches. It is now done only if the
2960 amount of subject to be scanned is less than 1000 bytes.
2962 7. A lesser problem with the same optimization is that it was recording the
2963 first character of an anchored pattern as "needed", thus provoking a search
2964 right along the subject, even when the first match of the pattern was going to
2965 fail. The "needed" character is now not set for anchored patterns, unless it
2966 follows something in the pattern that is of non-fixed length. Thus, it still
2967 fulfils its original purpose of finding quick non-matches in cases of nested
2968 unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
2971 Version 4.0 17-Feb-03
2972 ---------------------
2974 1. If a comment in an extended regex that started immediately after a meta-item
2975 extended to the end of string, PCRE compiled incorrect data. This could lead to
2976 all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
2978 2. Moved to autoconf 2.53 and libtool 1.4.2.
2980 3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
2981 the special perltest8 script is no longer needed - all the tests can be run
2982 from a single perltest script.
2984 4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
2985 by \s. It has now been removed in PCRE. This means it isn't recognized as
2986 whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
2987 class [:space:] *does* include VT, thereby creating a mess.
2989 5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
2990 space and tab.
2992 6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
2993 its new features into the main test script, reducing the number of scripts.
2995 7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
2996 were backward compatible, and made the (?i) apply to the whole pattern, as if
2997 /i were given. Now it behaves more logically, and applies the option setting
2998 only to what follows. PCRE has been changed to follow suit. However, if it
2999 finds options settings right at the start of the pattern, it extracts them into
3000 the global options, as before. Thus, they show up in the info data.
3002 8. Added support for the \Q...\E escape sequence. Characters in between are
3003 treated as literals. This is slightly different from Perl in that $ and @ are
3004 also handled as literals inside the quotes. In Perl, they will cause variable
3005 interpolation. Note the following examples:
3007 Pattern PCRE matches Perl matches
3009 \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
3010 \Qabc\$xyz\E abc\$xyz abc\$xyz
3011 \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
3013 For compatibility with Perl, \Q...\E sequences are recognized inside character
3014 classes as well as outside them.
3016 9. Re-organized 3 code statements in pcretest to avoid "overflow in
3017 floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
3018 (size_t) cast to one statement in pcretest and one in pcreposix to avoid
3019 signed/unsigned warnings.
3021 10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
3022 option for pcretest, so I've replaced it by a simple function that does just
3023 that job.
3025 11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
3026 "pcregrep -".
3028 12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
3029 Java package. This provides some syntactic sugar for simple cases of what my
3030 documentation calls "once-only subpatterns". A pattern such as x*+ is the same
3031 as (?>x*). In other words, if what is inside (?>...) is just a single repeated
3032 item, you can use this simplified notation. Note that only makes sense with
3033 greedy quantifiers. Consequently, the use of the possessive quantifier forces
3034 greediness, whatever the setting of the PCRE_UNGREEDY option.
3036 13. A change of greediness default within a pattern was not taking effect at
3037 the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
3038 subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
3039 was abstracted outside.
3041 14. PCRE now supports the \G assertion. It is true when the current matching
3042 position is at the start point of the match. This differs from \A when the
3043 starting offset is non-zero. Used with the /g option of pcretest (or similar
3044 code), it works in the same way as it does for Perl's /g option. If all
3045 alternatives of a regex begin with \G, the expression is anchored to the start
3046 match position, and the "anchored" flag is set in the compiled expression.
3048 15. Some bugs concerning the handling of certain option changes within patterns
3049 have been fixed. These applied to options other than (?ims). For example,
3050 "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
3051 been the other way round. Some of this was related to change 7 above.
3053 16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
3054 features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
3055 and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
3056 POSIX classes only within a class (e.g. /[[:alpha:]]/).
3058 17. Added support for Perl's \C escape. This matches one byte, even in UTF8
3059 mode. Unlike ".", it always matches newline, whatever the setting of
3060 PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
3061 assertions. Perl allows it, but it doesn't (in general) work because it can't
3062 calculate the length of the lookbehind. At least, that's the case for Perl
3063 5.8.0 - I've been told they are going to document that it doesn't work in
3064 future.
3066 18. Added an error diagnosis for escapes that PCRE does not support: these are
3067 \L, \l, \N, \P, \p, \U, \u, and \X.
3069 19. Although correctly diagnosing a missing ']' in a character class, PCRE was
3070 reading past the end of the pattern in cases such as /[abcd/.
3072 20. PCRE was getting more memory than necessary for patterns with classes that
3073 contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
3075 21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
3076 compiling PCRE for use with Virtual Pascal.
3078 22. Small fix to the Makefile to make it work properly if the build is done
3079 outside the source tree.
3081 23. Added a new extension: a condition to go with recursion. If a conditional
3082 subpattern starts with (?(R) the "true" branch is used if recursion has
3083 happened, whereas the "false" branch is used only at the top level.
3085 24. When there was a very long string of literal characters (over 255 bytes
3086 without UTF support, over 250 bytes with UTF support), the computation of how
3087 much memory was required could be incorrect, leading to segfaults or other
3088 strange effects.
3090 25. PCRE was incorrectly assuming anchoring (either to start of subject or to
3091 start of line for a non-DOTALL pattern) when a pattern started with (.*) and
3092 there was a subsequent back reference to those brackets. This meant that, for
3093 example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
3094 possible to check for precisely this case. All we can do is abandon the
3095 optimization if .* occurs inside capturing brackets when there are any back
3096 references whatsoever. (See below for a better fix that came later.)
3098 26. The handling of the optimization for finding the first character of a
3099 non-anchored pattern, and for finding a character that is required later in the
3100 match were failing in some cases. This didn't break the matching; it just
3101 failed to optimize when it could. The way this is done has been re-implemented.
3103 27. Fixed typo in error message for invalid (?R item (it said "(?p").
3105 28. Added a new feature that provides some of the functionality that Perl
3106 provides with (?{...}). The facility is termed a "callout". The way it is done
3107 in PCRE is for the caller to provide an optional function, by setting
3108 pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
3109 global variable. By default it is unset, which disables all calling out. To get
3110 the function called, the regex must include (?C) at appropriate points. This
3111 is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
3112 This provides a means of identifying different callout points. When PCRE
3113 reaches such a point in the regex, if pcre_callout has been set, the external
3114 function is called. It is provided with data in a structure called
3115 pcre_callout_block, which is defined in pcre.h. If the function returns 0,
3116 matching continues; if it returns a non-zero value, the match at the current
3117 point fails. However, backtracking will occur if possible. [This was changed
3118 later and other features added - see item 49 below.]
3120 29. pcretest is upgraded to test the callout functionality. It provides a
3121 callout function that displays information. By default, it shows the start of
3122 the match and the current position in the text. There are some new data escapes
3123 to vary what happens:
3125 \C+ in addition, show current contents of captured substrings
3126 \C- do not supply a callout function
3127 \C!n return 1 when callout number n is reached
3128 \C!n!m return 1 when callout number n is reached for the mth time
3130 30. If pcregrep was called with the -l option and just a single file name, it
3131 output "<stdin>" if a match was found, instead of the file name.
3133 31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
3134 slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
3135 pcre_exec(). This saves a malloc/free per call. The default value of
3136 POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
3137 when configuring.
3139 32. The default maximum size of a compiled pattern is 64K. There have been a
3140 few cases of people hitting this limit. The code now uses macros to handle the
3141 storing of links as offsets within the compiled pattern. It defaults to 2-byte
3142 links, but this can be changed to 3 or 4 bytes by --with-link-size when
3143 configuring. Tests 2 and 5 work only with 2-byte links because they output
3144 debugging information about compiled patterns.
3146 33. Internal code re-arrangements:
3148 (a) Moved the debugging function for printing out a compiled regex into
3149 its own source file (printint.c) and used #include to pull it into
3150 pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
3151 separate copies.
3153 (b) Defined the list of op-code names for debugging as a macro in
3154 internal.h so that it is next to the definition of the opcodes.
3156 (c) Defined a table of op-code lengths for simpler skipping along compiled
3157 code. This is again a macro in internal.h so that it is next to the
3158 definition of the opcodes.
3160 34. Added support for recursive calls to individual subpatterns, along the
3161 lines of Robin Houston's patch (but implemented somewhat differently).
3163 35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
3164 allow it to read and process whole directories in Win32. This code was
3165 contributed by Lionel Fourquaux; it has not been tested by me.
3167 36. Added support for named subpatterns. The Python syntax (?P<name>...) is
3168 used to name a group. Names consist of alphanumerics and underscores, and must
3169 be unique. Back references use the syntax (?P=name) and recursive calls use
3170 (?P>name) which is a PCRE extension to the Python extension. Groups still have
3171 numbers. The function pcre_fullinfo() can be used after compilation to extract
3172 a name/number map. There are three relevant calls:
3174 PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
3175 PCRE_INFO_NAMECOUNT yields the number of entries
3176 PCRE_INFO_NAMETABLE yields a pointer to the map.
3178 The map is a vector of fixed-size entries. The size of each entry depends on
3179 the length of the longest name used. The first two bytes of each entry are the
3180 group number, most significant byte first. There follows the corresponding
3181 name, zero terminated. The names are in alphabetical order.
3183 37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
3184 case instead of 255. Making it the same both with and without UTF-8 support
3185 means that the same test output works with both.
3187 38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
3188 calling malloc() with a zero argument.
3190 39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
3191 optimization. I've improved things by keeping a bitmap of backreferences with
3192 numbers 1-31 so that if .* occurs inside capturing brackets that are not in
3193 fact referenced, the optimization can be applied. It is unlikely that a
3194 relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
3195 the match to follow \n) will appear inside brackets with a number greater than
3196 31, but if it does, any back reference > 31 suppresses the optimization.
3198 40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
3199 of disabling numbered capturing parentheses. Any opening parenthesis that is
3200 not followed by ? behaves as if it were followed by ?: but named parentheses
3201 can still be used for capturing (and they will acquire numbers in the usual
3202 way).
3204 41. Redesigned the return codes from the match() function into yes/no/error so
3205 that errors can be passed back from deep inside the nested calls. A malloc
3206 failure while inside a recursive subpattern call now causes the
3207 PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
3209 42. It is now possible to set a limit on the number of times the match()
3210 function is called in a call to pcre_exec(). This facility makes it possible to
3211 limit the amount of recursion and backtracking, though not in a directly
3212 obvious way, because the match() function is used in a number of different
3213 circumstances. The count starts from zero for each position in the subject
3214 string (for non-anchored patterns). The default limit is, for compatibility, a
3215 large number, namely 10 000 000. You can change this in two ways:
3217 (a) When configuring PCRE before making, you can use --with-match-limit=n
3218 to set a default value for the compiled library.
3220 (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
3221 a different value is set. See 45 below.
3223 If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
3225 43. Added a new function pcre_config(int, void *) to enable run-time extraction
3226 of things that can be changed at compile time. The first argument specifies
3227 what is wanted and the second points to where the information is to be placed.
3228 The current list of available information is:
3232 The output is an integer that is set to one if UTF-8 support is available;
3233 otherwise it is set to zero.
3237 The output is an integer that it set to the value of the code that is used for
3238 newline. It is either LF (10) or CR (13).
3242 The output is an integer that contains the number of bytes used for internal
3243 linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
3247 The output is an integer that contains the threshold above which the POSIX
3248 interface uses malloc() for output vectors. See item 31 above.
3252 The output is an unsigned integer that contains the default limit of the number
3253 of match() calls in a pcre_exec() execution. See 42 above.
3255 44. pcretest has been upgraded by the addition of the -C option. This causes it
3256 to extract all the available output from the new pcre_config() function, and to
3257 output it. The program then exits immediately.
3259 45. A need has arisen to pass over additional data with calls to pcre_exec() in
3260 order to support additional features. One way would have been to define
3261 pcre_exec2() (for example) with extra arguments, but this would not have been
3262 extensible, and would also have required all calls to the original function to
3263 be mapped to the new one. Instead, I have chosen to extend the mechanism that
3264 is used for passing in "extra" data from pcre_study().
3266 The pcre_extra structure is now exposed and defined in pcre.h. It currently
3267 contains the following fields:
3269 flags a bitmap indicating which of the following fields are set
3270 study_data opaque data from pcre_study()
3271 match_limit a way of specifying a limit on match() calls for a specific
3272 call to pcre_exec()
3273 callout_data data for callouts (see 49 below)
3275 The flag bits are also defined in pcre.h, and are
3281 The pcre_study() function now returns one of these new pcre_extra blocks, with
3282 the actual study data pointed to by the study_data field, and the
3283 PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
3284 before. That is, this change is entirely upwards-compatible and requires no
3285 change to existing code.
3287 If you want to pass in additional data to pcre_exec(), you can either place it
3288 in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
3289 block.
3291 46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
3292 data string contains the escape sequence \M, pcretest calls pcre_exec() several
3293 times with different match limits, until it finds the minimum value needed for
3294 pcre_exec() to complete. The value is then output. This can be instructive; for
3295 most simple matches the number is quite small, but for pathological cases it
3296 gets very large very quickly.
3298 47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
3299 returns the size of the data block pointed to by the study_data field in a
3300 pcre_extra block, that is, the value that was passed as the argument to
3301 pcre_malloc() when PCRE was getting memory in which to place the information
3302 created by pcre_study(). The fourth argument should point to a size_t variable.
3303 pcretest has been extended so that this information is shown after a successful
3304 pcre_study() call when information about the compiled regex is being displayed.
3306 48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
3307 because what follows is always an absolute path. (Later: it turns out that this
3308 is more than cosmetic for MinGW, because it doesn't like empty path
3309 components.)
3311 49. Some changes have been made to the callout feature (see 28 above):
3313 (i) A callout function now has three choices for what it returns:
3315 0 => success, carry on matching
3316 > 0 => failure at this point, but backtrack if possible
3317 < 0 => serious error, return this value from pcre_exec()
3319 Negative values should normally be chosen from the set of PCRE_ERROR_xxx
3320 values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
3321 "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
3322 use by callout functions. It will never be used by PCRE itself.
3324 (ii) The pcre_extra structure (see 45 above) has a void * field called
3325 callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
3326 pcre_callout_block structure has a field of the same name. The contents of
3327 the field passed in the pcre_extra structure are passed to the callout
3328 function in the corresponding field in the callout block. This makes it
3329 easier to use the same callout-containing regex from multiple threads. For
3330 testing, the pcretest program has a new data escape
3332 \C*n pass the number n (may be negative) as callout_data
3334 If the callout function in pcretest receives a non-zero value as
3335 callout_data, it returns that value.
3337 50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
3338 there were some redundant $(CFLAGS) in commands that are now specified as
3339 $(LINK), which already includes $(CFLAGS).
3341 51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
3342 has been compiled with UTF-8 support *and* pcre_compile() has been compiled
3343 with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
3344 one-byte characters throughout. Note that case-insensitive matching applies
3345 only to characters whose values are less than 256. PCRE doesn't support the
3346 notion of cases for higher-valued characters.
3348 (i) A character class whose characters are all within 0-255 is handled as
3349 a bit map, and the map is inverted for negative classes. Previously, a
3350 character > 255 always failed to match such a class; however it should
3351 match if the class was a negative one (e.g. [^ab]). This has been fixed.
3353 (ii) A negated character class with a single character < 255 is coded as
3354 "not this character" (OP_NOT). This wasn't working properly when the test
3355 character was multibyte, either singly or repeated.
3357 (iii) Repeats of multibyte characters are now handled correctly in UTF-8
3358 mode, for example: \x{100}{2,3}.
3360 (iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
3361 singly or repeated) now correctly test multibyte characters. However,
3362 PCRE doesn't recognize any characters with values greater than 255 as
3363 digits, spaces, or word characters. Such characters always match \D, \S,
3364 and \W, and never match \d, \s, or \w.
3366 (v) Classes may now contain characters and character ranges with values
3367 greater than 255. For example: [ab\x{100}-\x{400}].
3369 (vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
3370 PCRE in UTF-8 mode.
3372 52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
3373 PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
3374 retained for backwards compatibility. (Note that LASTLITERAL is also a byte
3375 value.)
3377 53. The single man page has become too large. I have therefore split it up into
3378 a number of separate man pages. These also give rise to individual HTML pages;
3379 these are now put in a separate directory, and there is an index.html page that
3380 lists them all. Some hyperlinking between the pages has been installed.
3382 54. Added convenience functions for handling named capturing parentheses.
3384 55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
3385 aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
3386 true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
3387 are faulted.
3389 56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
3390 calling configure. These values are used when compiling the dftables.c program
3391 which is run to generate the source of the default character tables. They
3392 default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
3393 you will need to set these values.
3395 57. Updated the building process for Windows DLL, as provided by Fred Cox.
3398 Version 3.9 02-Jan-02
3399 ---------------------
3401 1. A bit of extraneous text had somehow crept into the pcregrep documentation.
3403 2. If --disable-static was given, the building process failed when trying to
3404 build pcretest and pcregrep. (For some reason it was using libtool to compile
3405 them, which is not right, as they aren't part of the library.)
3408 Version 3.8 18-Dec-01
3409 ---------------------
3411 1. The experimental UTF-8 code was completely screwed up. It was packing the
3412 bytes in the wrong order. How dumb can you get?
3415 Version 3.7 29-Oct-01
3416 ---------------------
3418 1. In updating pcretest to check change 1 of version 3.6, I screwed up.
3419 This caused pcretest, when used on the test data, to segfault. Unfortunately,
3420 this didn't happen under Solaris 8, where I normally test things.
3422 2. The Makefile had to be changed to make it work on BSD systems, where 'make'
3423 doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
3424 isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
3425 this fix an hour or so after the initial 3.7 release.)
3428 Version 3.6 23-Oct-01
3429 ---------------------
3431 1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
3432 offsets passed as NULL with zero offset count.
3434 2. The config.guess and config.sub files had not been updated when I moved to
3435 the latest autoconf.
3438 Version 3.5 15-Aug-01
3439 ---------------------
3441 1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
3442 had been forgotten.
3444 2. By using declared but undefined structures, we can avoid using "void"
3445 definitions in pcre.h while keeping the internal definitions of the structures
3446 private.
3448 3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
3449 user point of view, this means that both static and shared libraries are built
3450 by default, but this can be individually controlled. More of the work of
3451 handling this static/shared cases is now inside libtool instead of PCRE's make
3452 file.
3454 4. The pcretest utility is now installed along with pcregrep because it is
3455 useful for users (to test regexs) and by doing this, it automatically gets
3456 relinked by libtool. The documentation has been turned into a man page, so
3457 there are now .1, .txt, and .html versions in /doc.
3459 5. Upgrades to pcregrep:
3460 (i) Added long-form option names like gnu grep.
3461 (ii) Added --help to list all options with an explanatory phrase.
3462 (iii) Added -r, --recursive to recurse into sub-directories.
3463 (iv) Added -f, --file to read patterns from a file.
3465 6. pcre_exec() was referring to its "code" argument before testing that
3466 argument for NULL (and giving an error if it was NULL).
3468 7. Upgraded Makefile.in to allow for compiling in a different directory from
3469 the source directory.
3471 8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
3472 options bits, the pointer it was passed was to an int instead of to an unsigned
3473 long int. This mattered only on 64-bit systems.
3475 9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
3476 generated) instead of pcre.in, which it its source. Also made the same change
3477 in several of the .c files.
3479 10. A new release of gcc defines printf() as a macro, which broke pcretest
3480 because it had an ifdef in the middle of a string argument for printf(). Fixed
3481 by using separate calls to printf().
3483 11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
3484 script, to force use of CR or LF instead of \n in the source. On non-Unix
3485 systems, the value can be set in config.h.
3487 12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
3488 absolute limit. Changed the text of the error message to make this clear, and
3489 likewise updated the man page.
3491 13. The limit of 99 on the number of capturing subpatterns has been removed.
3492 The new limit is 65535, which I hope will not be a "real" limit.
3495 Version 3.4 22-Aug-00
3496 ---------------------
3498 1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
3500 2. Diagnose condition (?(0) as an error instead of crashing on matching.
3503 Version 3.3 01-Aug-00
3504 ---------------------
3506 1. If an octal character was given, but the value was greater than \377, it
3507 was not getting masked to the least significant bits, as documented. This could
3508 lead to crashes in some systems.
3510 2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
3511 the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
3513 3. Added the functions pcre_free_substring() and pcre_free_substring_list().
3514 These just pass their arguments on to (pcre_free)(), but they are provided
3515 because some uses of PCRE bind it to non-C systems that can call its functions,
3516 but cannot call free() or pcre_free() directly.
3518 4. Add "make test" as a synonym for "make check". Corrected some comments in
3519 the Makefile.
3521 5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
3522 Makefile.
3524 6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
3525 command called pgrep for grepping around the active processes.
3527 7. Added the beginnings of support for UTF-8 character strings.
3529 8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
3530 RANLIB to ./ltconfig so that they are used by libtool. I think these are all
3531 the relevant ones. (AR is not passed because ./ltconfig does its own figuring
3532 out for the ar command.)
3535 Version 3.2 12-May-00
3536 ---------------------
3538 This is purely a bug fixing release.
3540 1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
3541 of ZA. This was just one example of several cases that could provoke this bug,
3542 which was introduced by change 9 of version 2.00. The code for breaking
3543 infinite loops after an iteration that matches an empty string was't working
3544 correctly.
3546 2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
3547 when matched against abbab (for example). After matching an empty string, it
3548 wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
3549 caused it to match further down the string than it should.
3551 3. The code contained an inclusion of sys/types.h. It isn't clear why this
3552 was there because it doesn't seem to be needed, and it causes trouble on some
3553 systems, as it is not a Standard C header. It has been removed.
3555 4. Made 4 silly changes to the source to avoid stupid compiler warnings that
3556 were reported on the Macintosh. The changes were from
3558 while ((c = *(++ptr)) != 0 && c != '\n');
3559 to
3560 while ((c = *(++ptr)) != 0 && c != '\n') ;
3562 Totally extraordinary, but if that's what it takes...
3564 5. PCRE is being used in one environment where neither memmove() nor bcopy() is
3565 available. Added HAVE_BCOPY and an autoconf test for it; if neither
3566 HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
3567 assumes the way PCRE uses memmove() (always moving upwards).
3569 6. PCRE is being used in one environment where strchr() is not available. There
3570 was only one use in pcre.c, and writing it out to avoid strchr() probably gives
3571 faster code anyway.
3574 Version 3.1 09-Feb-00
3575 ---------------------
3577 The only change in this release is the fixing of some bugs in Makefile.in for
3578 the "install" target:
3580 (1) It was failing to install pcreposix.h.
3582 (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
3585 Version 3.0 01-Feb-00
3586 ---------------------
3588 1. Add support for the /+ modifier to perltest (to output $` like it does in
3589 pcretest).
3591 2. Add support for the /g modifier to perltest.
3593 3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
3594 matches null strings.
3596 4. Fix perltest so that it doesn't do unwanted things when fed an empty
3597 pattern. Perl treats empty patterns specially - it reuses the most recent
3598 pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
3599 effect.
3601 5. The POSIX interface was broken in that it was just handing over the POSIX
3602 captured string vector to pcre_exec(), but (since release 2.00) PCRE has
3603 required a bigger vector, with some working space on the end. This means that
3604 the POSIX wrapper now has to get and free some memory, and copy the results.
3606 6. Added some simple autoconf support, placing the test data and the
3607 documentation in separate directories, re-organizing some of the
3608 information files, and making it build pcre-config (a GNU standard). Also added
3609 libtool support for building PCRE as a shared library, which is now the
3610 default.
3612 7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
3613 09 are not valid octal constants. Single digits will be used for minor values
3614 less than 10.
3616 8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
3617 existing programs that set these in the POSIX interface can use PCRE without
3618 modification.
3620 9. Added a new function, pcre_fullinfo() with an extensible interface. It can
3621 return all that pcre_info() returns, plus additional data. The pcre_info()
3622 function is retained for compatibility, but is considered to be obsolete.
3624 10. Added experimental recursion feature (?R) to handle one common case that
3625 Perl 5.6 will be able to do with (?p{...}).
3627 11. Added support for POSIX character classes like [:alpha:], which Perl is
3628 adopting.
3631 Version 2.08 31-Aug-99
3632 ----------------------
3634 1. When startoffset was not zero and the pattern began with ".*", PCRE was not
3635 trying to match at the startoffset position, but instead was moving forward to
3636 the next newline as if a previous match had failed.
3638 2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
3639 and could get into a loop if a null string was matched other than at the start
3640 of the subject.
3642 3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
3643 be distinguished at compile time, and for completeness also added PCRE_DATE.
3645 5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
3646 in GnuWin32 environments.
3649 Version 2.07 29-Jul-99
3650 ----------------------
3652 1. The documentation is now supplied in plain text form and HTML as well as in
3653 the form of man page sources.
3655 2. C++ compilers don't like assigning (void *) values to other pointer types.
3656 In particular this affects malloc(). Although there is no problem in Standard
3657 C, I've put in casts to keep C++ compilers happy.
3659 3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
3660 should be (const char *).
3662 4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
3663 be useful for non-Unix systems who don't want to bother with the POSIX stuff.
3664 However, I haven't made this a standard facility. The documentation doesn't
3665 mention it, and the Makefile doesn't support it.
3667 5. The Makefile now contains an "install" target, with editable destinations at
3668 the top of the file. The pcretest program is not installed.
3670 6. pgrep -V now gives the PCRE version number and date.
3672 7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
3673 causing the entire string to be ignored, instead of just the last character.
3675 8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
3676 non-matching string, it can take a very, very long time, even for strings of
3677 quite modest length, because of the nested recursion. PCRE now does better in
3678 some of these cases. It does this by remembering the last required literal
3679 character in the pattern, and pre-searching the subject to ensure it is present
3680 before running the real match. In other words, it applies a heuristic to detect
3681 some types of certain failure quickly, and in the above example, if presented
3682 with a string that has no trailing " it gives "no match" very quickly.
3684 9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
3685 other alternatives are tried instead.
3688 Version 2.06 09-Jun-99
3689 ----------------------
3691 1. Change pcretest's output for amount of store used to show just the code
3692 space, because the remainder (the data block) varies in size between 32-bit and
3693 64-bit systems.
3695 2. Added an extra argument to pcre_exec() to supply an offset in the subject to
3696 start matching at. This allows lookbehinds to work when searching for multiple
3697 occurrences in a string.
3699 3. Added additional options to pcretest for testing multiple occurrences:
3701 /+ outputs the rest of the string that follows a match
3702 /g loops for multiple occurrences, using the new startoffset argument
3703 /G loops for multiple occurrences by passing an incremented pointer
3705 4. PCRE wasn't doing the "first character" optimization for patterns starting
3706 with \b or \B, though it was doing it for other lookbehind assertions. That is,
3707 it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
3708 the letter 'x'. On long subject strings, this gives a significant speed-up.
3711 Version 2.05 21-Apr-99
3712 ----------------------
3714 1. Changed the type of magic_number from int to long int so that it works
3715 properly on 16-bit systems.
3717 2. Fixed a bug which caused patterns starting with .* not to work correctly
3718 when the subject string contained newline characters. PCRE was assuming
3719 anchoring for such patterns in all cases, which is not correct because .* will
3720 not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
3721 DOTALL is set at top level; otherwise it knows that patterns starting with .*
3722 must be retried after every newline in the subject.
3725 Version 2.04 18-Feb-99
3726 ----------------------
3728 1. For parenthesized subpatterns with repeats whose minimum was zero, the
3729 computation of the store needed to hold the pattern was incorrect (too large).
3730 If such patterns were nested a few deep, this could multiply and become a real
3731 problem.
3733 2. Added /M option to pcretest to show the memory requirement of a specific
3734 pattern. Made -m a synonym of -s (which does this globally) for compatibility.
3736 3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
3737 compiled in such a way that the backtracking after subsequent failure was
3738 pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
3739 ((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
3742 Version 2.03 02-Feb-99
3743 ----------------------
3745 1. Fixed typo and small mistake in man page.
3747 2. Added 4th condition (GPL supersedes if conflict) and created separate
3748 LICENCE file containing the conditions.
3750 3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
3751 Perl, that is the internal \ allows the delimiter to be included in the
3752 pattern. Locked out the use of \ as a delimiter. If \ immediately follows
3753 the final delimiter, add \ to the end of the pattern (to test the error).
3755 4. Added the convenience functions for extracting substrings after a successful
3756 match. Updated pcretest to make it able to test these functions.
3759 Version 2.02 14-Jan-99
3760 ----------------------
3762 1. Initialized the working variables associated with each extraction so that
3763 their saving and restoring doesn't refer to uninitialized store.
3765 2. Put dummy code into study.c in order to trick the optimizer of the IBM C
3766 compiler for OS/2 into generating correct code. Apparently IBM isn't going to
3767 fix the problem.
3769 3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
3770 calls, and wasn't printing the correct value for compiling calls. Increased the
3771 default value of LOOPREPEAT, and the number of significant figures in the
3772 times.
3774 4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
3776 5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
3777 a building problem on Windows NT with a FAT file system.
3780 Version 2.01 21-Oct-98
3781 ----------------------
3783 1. Changed the API for pcre_compile() to allow for the provision of a pointer
3784 to character tables built by pcre_maketables() in the current locale. If NULL
3785 is passed, the default tables are used.
3788 Version 2.00 24-Sep-98
3789 ----------------------
3791 1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
3792 it any more.
3794 2. Allow quantification of (?>) groups, and make it work correctly.
3796 3. The first character computation wasn't working for (?>) groups.
3798 4. Correct the implementation of \Z (it is permitted to match on the \n at the
3799 end of the subject) and add 5.005's \z, which really does match only at the
3800 very end of the subject.
3802 5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
3804 6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
3805 DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
3806 localized options. All options to pcre_study() were also removed.
3808 7. Add other new features from 5.005:
3810 $(?<= positive lookbehind
3811 $(?<! negative lookbehind
3812 (?imsx-imsx) added the unsetting capability
3813 such a setting is global if at outer level; local otherwise
3814 (?imsx-imsx:) non-capturing groups with option setting
3815 (?(cond)re|re) conditional pattern matching
3817 A backreference to itself in a repeated group matches the previous
3818 captured string.
3820 8. General tidying up of studying (both automatic and via "study")
3821 consequential on the addition of new assertions.
3823 9. As in 5.005, unlimited repeated groups that could match an empty substring
3824 are no longer faulted at compile time. Instead, the loop is forcibly broken at
3825 runtime if any iteration does actually match an empty substring.
3827 10. Include the RunTest script in the distribution.
3829 11. Added tests from the Perl 5.005_02 distribution. This showed up a few
3830 discrepancies, some of which were old and were also with respect to 5.004. They
3831 have now been fixed.
3834 Version 1.09 28-Apr-98
3835 ----------------------
3837 1. A negated single character class followed by a quantifier with a minimum
3838 value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
3839 program crashes, or just wrong answers. This did not apply to negated classes
3840 containing more than one character, or to minima other than one.
3843 Version 1.08 27-Mar-98
3844 ----------------------
3846 1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
3848 2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
3849 latter must appear before anything that relies on it in the pattern.
3852 Version 1.07 16-Feb-98
3853 ----------------------
3855 1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
3856 repeat of a potentially empty string).
3859 Version 1.06 23-Jan-98
3860 ----------------------
3862 1. Added Markus Oberhumer's little patches for C++.
3864 2. Literal strings longer than 255 characters were broken.
3867 Version 1.05 23-Dec-97
3868 ----------------------
3870 1. Negated character classes containing more than one character were failing if
3871 PCRE_CASELESS was set at run time.
3874 Version 1.04 19-Dec-97
3875 ----------------------
3877 1. Corrected the man page, where some "const" qualifiers had been omitted.
3879 2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
3880 input syntax.
3882 3. Fixed memory leak which occurred when a regex with back references was
3883 matched with an offsets vector that wasn't big enough. The temporary memory
3884 that is used in this case wasn't being freed if the match failed.
3886 4. Tidied pcretest to ensure it frees memory that it gets.
3888 5. Temporary memory was being obtained in the case where the passed offsets
3889 vector was exactly big enough.
3891 6. Corrected definition of offsetof() from change 5 below.
3893 7. I had screwed up change 6 below and broken the rules for the use of
3894 setjmp(). Now fixed.
3897 Version 1.03 18-Dec-97
3898 ----------------------
3900 1. A erroneous regex with a missing opening parenthesis was correctly
3901 diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
3902 on some systems.
3904 2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
3905 it was reported that one broken compiler failed on the former because "code" is
3906 also an independent variable.
3908 3. The erroneous regex a[]b caused an array overrun reference.
3910 4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
3911 fail on data ending with that character. (It was going on too far, and checking
3912 the next character, typically a binary zero.) This was specific to the
3913 optimized code for single-character negative classes.
3915 5. Added a contributed patch from the TIN world which does the following:
3917 + Add an undef for memmove, in case the the system defines a macro for it.
3919 + Add a definition of offsetof(), in case there isn't one. (I don't know
3920 the reason behind this - offsetof() is part of the ANSI standard - but
3921 it does no harm).
3923 + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
3924 most of the places where whitespace preceded '#'. I have given up and
3925 allowed the remaining 2 cases to be at the margin.
3927 + Rename some variables in pcre to eliminate shadowing. This seems very
3928 pedantic, but does no harm, of course.
3930 6. Moved the call to setjmp() into its own function, to get rid of warnings
3931 from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
3933 7. Constructs such as \d{8,} were compiling into the equivalent of
3934 \d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
3935 outcome, but in this particular case used more store than had been allocated,
3936 which caused the bug to be discovered because it threw up an internal error.
3938 8. The debugging code in both pcre and pcretest for outputting the compiled
3939 form of a regex was going wrong in the case of back references followed by
3940 curly-bracketed repeats.
3943 Version 1.02 12-Dec-97
3944 ----------------------
3946 1. Typos in pcre.3 and comments in the source fixed.
3948 2. Applied a contributed patch to get rid of places where it used to remove
3949 'const' from variables, and fixed some signed/unsigned and uninitialized
3950 variable warnings.
3952 3. Added the "runtest" target to Makefile.
3954 4. Set default compiler flag to -O2 rather than just -O.
3957 Version 1.01 19-Nov-97
3958 ----------------------
3960 1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
3961 like /([ab]*)*/, that is, for classes with more than one character in them.
3963 2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
3964 as /((?>a*))*/ (a PCRE_EXTRA facility).
3967 Version 1.00 18-Nov-97
3968 ----------------------
3970 1. Added compile-time macros to support systems such as SunOS4 which don't have
3971 memmove() or strerror() but have other things that can be used instead.
3973 2. Arranged that "make clean" removes the executables.
3976 Version 0.99 27-Oct-97
3977 ----------------------
3979 1. Fixed bug in code for optimizing classes with only one character. It was
3980 initializing a 32-byte map regardless, which could cause it to run off the end
3981 of the memory it had got.
3983 2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
3986 Version 0.98 22-Oct-97
3987 ----------------------
3989 1. Fixed bug in code for handling temporary memory usage when there are more
3990 back references than supplied space in the ovector. This could cause segfaults.
3993 Version 0.97 21-Oct-97
3994 ----------------------
3996 1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
3998 2. Optimized negated single characters not to use a bit map.
4000 3. Brought error texts together as macro definitions; clarified some of them;
4001 fixed one that was wrong - it said "range out of order" when it meant "invalid
4002 escape sequence".
4004 4. Changed some char * arguments to const char *.
4006 5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
4008 6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
4009 pcretest.
4012 Version 0.96 16-Oct-97
4013 ----------------------
4015 1. Added a simple "pgrep" utility to the distribution.
4017 2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
4018 unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
4019 where "ddd" means "one or more decimal digits".
4021 3. Fixed serious bug. If a pattern had a back reference, but the call to
4022 pcre_exec() didn't supply a large enough ovector to record the related
4023 identifying subpattern, the match always failed. PCRE now remembers the number
4024 of the largest back reference, and gets some temporary memory in which to save
4025 the offsets during matching if necessary, in order to ensure that
4026 backreferences always work.
4028 4. Increased the compatibility with Perl in a number of ways:
4030 (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
4031 to request this handling. The option can be set at compile or exec time.
4033 (b) $ matches before a terminating newline by default; an option
4034 PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
4035 mode). The option can be set at compile or exec time.
4037 (c) The handling of \ followed by a digit other than 0 is now supposed to be
4038 the same as Perl's. If the decimal number it represents is less than 10
4039 or there aren't that many previous left capturing parentheses, an octal
4040 escape is read. Inside a character class, it's always an octal escape,
4041 even if it is a single digit.
4043 (d) An escaped but undefined alphabetic character is taken as a literal,
4044 unless PCRE_EXTRA is set. Currently this just reserves the remaining
4045 escapes.
4047 (e) {0} is now permitted. (The previous item is removed from the compiled
4048 pattern).
4050 5. Changed all the names of code files so that the basic parts are no longer
4051 than 10 characters, and abolished the teeny "globals.c" file.
4053 6. Changed the handling of character classes; they are now done with a 32-byte
4054 bit map always.
4056 7. Added the -d and /D options to pcretest to make it possible to look at the
4057 internals of compilation without having to recompile pcre.
4060 Version 0.95 23-Sep-97
4061 ----------------------
4063 1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
4064 \x20 at the start of a run of normal characters. These were being treated as
4065 real characters, instead of the source characters being re-checked.
4068 Version 0.94 18-Sep-97
4069 ----------------------
4071 1. The functions are now thread-safe, with the caveat that the global variables
4072 containing pointers to malloc() and free() or alternative functions are the
4073 same for all threads.
4075 2. Get pcre_study() to generate a bitmap of initial characters for non-
4076 anchored patterns when this is possible, and use it if passed to pcre_exec().
4079 Version 0.93 15-Sep-97
4080 ----------------------
4082 1. /(b)|(:+)/ was computing an incorrect first character.
4084 2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
4085 but not actually doing anything yet.
4087 3. Treat "-" characters in classes that cannot be part of ranges as literals,
4088 as Perl does (e.g. [-az] or [az-]).
4090 4. Set the anchored flag if a branch starts with .* or .*? because that tests
4091 all possible positions.
4093 5. Split up into different modules to avoid including unneeded functions in a
4094 compiled binary. However, compile and exec are still in one module. The "study"
4095 function is split off.
4097 6. The character tables are now in a separate module whose source is generated
4098 by an auxiliary program - but can then be edited by hand if required. There are
4099 now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
4100 toupper() in the code.
4102 7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
4103 make them global. Abolish the function for setting them, as the caller can now
4104 set them directly.
4107 Version 0.92 11-Sep-97
4108 ----------------------
4110 1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
4111 (e.g. /a{1,3}/) was broken (I mis-optimized it).
4113 2. Caseless matching was not working in character classes if the characters in
4114 the pattern were in upper case.
4116 3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
4118 4. Make PCRE_ANCHORED public and accept as a compile option.
4120 5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
4121 PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
4122 pass them.
4124 6. Give an error if bad option bits passed at compile or run time.
4126 7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
4127 pcretest to cause it to pass that flag.
4129 8. Add pcre_info(), to get the number of identifying subpatterns, the stored
4130 options, and the first character, if set.
4132 9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
4135 Version 0.91 10-Sep-97
4136 ----------------------
4138 1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
4139 match the empty string as in /(a*)*/. It was looping and ultimately crashing.
4141 2. PCRE was looping on encountering an indefinitely repeated back reference to
4142 a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
4143 Perl does - treats the match as successful.
4145 ****


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