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Revision 1611 - (show annotations)
Thu Nov 26 20:29:13 2015 UTC (3 years, 10 months ago) by ph10
File size: 285715 byte(s)
Fix auto-callout (?# comment bug.
1 ChangeLog for PCRE
2 ------------------
4 Note that the PCRE 8.xx series (PCRE1) is now in a bugfix-only state. All
5 development is happening in the PCRE2 10.xx series.
7 Version 8.39 xx-xxxxxx-201x
8 ---------------------------
10 1. If PCRE_AUTO_CALLOUT was set on a pattern that had a (?# comment between
11 an item and its qualifier (for example, A(?#comment)?B) pcre_compile()
12 misbehaved. This bug was found by the LLVM fuzzer.
15 Version 8.38 23-November-2015
16 -----------------------------
18 1. If a group that contained a recursive back reference also contained a
19 forward reference subroutine call followed by a non-forward-reference
20 subroutine call, for example /.((?2)(?R)\1)()/, pcre2_compile() failed to
21 compile correct code, leading to undefined behaviour or an internally
22 detected error. This bug was discovered by the LLVM fuzzer.
24 2. Quantification of certain items (e.g. atomic back references) could cause
25 incorrect code to be compiled when recursive forward references were
26 involved. For example, in this pattern: /(?1)()((((((\1++))\x85)+)|))/.
27 This bug was discovered by the LLVM fuzzer.
29 3. A repeated conditional group whose condition was a reference by name caused
30 a buffer overflow if there was more than one group with the given name.
31 This bug was discovered by the LLVM fuzzer.
33 4. A recursive back reference by name within a group that had the same name as
34 another group caused a buffer overflow. For example:
35 /(?J)(?'d'(?'d'\g{d}))/. This bug was discovered by the LLVM fuzzer.
37 5. A forward reference by name to a group whose number is the same as the
38 current group, for example in this pattern: /(?|(\k'Pm')|(?'Pm'))/, caused
39 a buffer overflow at compile time. This bug was discovered by the LLVM
40 fuzzer.
42 6. A lookbehind assertion within a set of mutually recursive subpatterns could
43 provoke a buffer overflow. This bug was discovered by the LLVM fuzzer.
45 7. Another buffer overflow bug involved duplicate named groups with a
46 reference between their definition, with a group that reset capture
47 numbers, for example: /(?J:(?|(?'R')(\k'R')|((?'R'))))/. This has been
48 fixed by always allowing for more memory, even if not needed. (A proper fix
49 is implemented in PCRE2, but it involves more refactoring.)
51 8. There was no check for integer overflow in subroutine calls such as (?123).
53 9. The table entry for \l in EBCDIC environments was incorrect, leading to its
54 being treated as a literal 'l' instead of causing an error.
56 10. There was a buffer overflow if pcre_exec() was called with an ovector of
57 size 1. This bug was found by american fuzzy lop.
59 11. If a non-capturing group containing a conditional group that could match
60 an empty string was repeated, it was not identified as matching an empty
61 string itself. For example: /^(?:(?(1)x|)+)+$()/.
63 12. In an EBCDIC environment, pcretest was mishandling the escape sequences
64 \a and \e in test subject lines.
66 13. In an EBCDIC environment, \a in a pattern was converted to the ASCII
67 instead of the EBCDIC value.
69 14. The handling of \c in an EBCDIC environment has been revised so that it is
70 now compatible with the specification in Perl's perlebcdic page.
72 15. The EBCDIC character 0x41 is a non-breaking space, equivalent to 0xa0 in
73 ASCII/Unicode. This has now been added to the list of characters that are
74 recognized as white space in EBCDIC.
76 16. When PCRE was compiled without UCP support, the use of \p and \P gave an
77 error (correctly) when used outside a class, but did not give an error
78 within a class.
80 17. \h within a class was incorrectly compiled in EBCDIC environments.
82 18. A pattern with an unmatched closing parenthesis that contained a backward
83 assertion which itself contained a forward reference caused buffer
84 overflow. And example pattern is: /(?=di(?<=(?1))|(?=(.))))/.
86 19. JIT should return with error when the compiled pattern requires more stack
87 space than the maximum.
89 20. A possessively repeated conditional group that could match an empty string,
90 for example, /(?(R))*+/, was incorrectly compiled.
92 21. Fix infinite recursion in the JIT compiler when certain patterns such as
93 /(?:|a|){100}x/ are analysed.
95 22. Some patterns with character classes involving [: and \\ were incorrectly
96 compiled and could cause reading from uninitialized memory or an incorrect
97 error diagnosis.
99 23. Pathological patterns containing many nested occurrences of [: caused
100 pcre_compile() to run for a very long time.
102 24. A conditional group with only one branch has an implicit empty alternative
103 branch and must therefore be treated as potentially matching an empty
104 string.
106 25. If (?R was followed by - or + incorrect behaviour happened instead of a
107 diagnostic.
109 26. Arrange to give up on finding the minimum matching length for overly
110 complex patterns.
112 27. Similar to (4) above: in a pattern with duplicated named groups and an
113 occurrence of (?| it is possible for an apparently non-recursive back
114 reference to become recursive if a later named group with the relevant
115 number is encountered. This could lead to a buffer overflow. Wen Guanxing
116 from Venustech ADLAB discovered this bug.
118 28. If pcregrep was given the -q option with -c or -l, or when handling a
119 binary file, it incorrectly wrote output to stdout.
121 29. The JIT compiler did not restore the control verb head in case of *THEN
122 control verbs. This issue was found by Karl Skomski with a custom LLVM
123 fuzzer.
125 30. Error messages for syntax errors following \g and \k were giving inaccurate
126 offsets in the pattern.
128 31. Added a check for integer overflow in conditions (?(<digits>) and
129 (?(R<digits>). This omission was discovered by Karl Skomski with the LLVM
130 fuzzer.
132 32. Handling recursive references such as (?2) when the reference is to a group
133 later in the pattern uses code that is very hacked about and error-prone.
134 It has been re-written for PCRE2. Here in PCRE1, a check has been added to
135 give an internal error if it is obvious that compiling has gone wrong.
137 33. The JIT compiler should not check repeats after a {0,1} repeat byte code.
138 This issue was found by Karl Skomski with a custom LLVM fuzzer.
140 34. The JIT compiler should restore the control chain for empty possessive
141 repeats. This issue was found by Karl Skomski with a custom LLVM fuzzer.
143 35. Match limit check added to JIT recursion. This issue was found by Karl
144 Skomski with a custom LLVM fuzzer.
146 36. Yet another case similar to 27 above has been circumvented by an
147 unconditional allocation of extra memory. This issue is fixed "properly" in
148 PCRE2 by refactoring the way references are handled. Wen Guanxing
149 from Venustech ADLAB discovered this bug.
151 37. Fix two assertion fails in JIT. These issues were found by Karl Skomski
152 with a custom LLVM fuzzer.
154 38. Fixed a corner case of range optimization in JIT.
156 39. An incorrect error "overran compiling workspace" was given if there were
157 exactly enough group forward references such that the last one extended
158 into the workspace safety margin. The next one would have expanded the
159 workspace. The test for overflow was not including the safety margin.
161 40. A match limit issue is fixed in JIT which was found by Karl Skomski
162 with a custom LLVM fuzzer.
164 41. Remove the use of /dev/null in testdata/testinput2, because it doesn't
165 work under Windows. (Why has it taken so long for anyone to notice?)
167 42. In a character class such as [\W\p{Any}] where both a negative-type escape
168 ("not a word character") and a property escape were present, the property
169 escape was being ignored.
171 43. Fix crash caused by very long (*MARK) or (*THEN) names.
173 44. A sequence such as [[:punct:]b] that is, a POSIX character class followed
174 by a single ASCII character in a class item, was incorrectly compiled in
175 UCP mode. The POSIX class got lost, but only if the single character
176 followed it.
178 45. [:punct:] in UCP mode was matching some characters in the range 128-255
179 that should not have been matched.
181 46. If [:^ascii:] or [:^xdigit:] or [:^cntrl:] are present in a non-negated
182 class, all characters with code points greater than 255 are in the class.
183 When a Unicode property was also in the class (if PCRE_UCP is set, escapes
184 such as \w are turned into Unicode properties), wide characters were not
185 correctly handled, and could fail to match.
188 Version 8.37 28-April-2015
189 --------------------------
191 1. When an (*ACCEPT) is triggered inside capturing parentheses, it arranges
192 for those parentheses to be closed with whatever has been captured so far.
193 However, it was failing to mark any other groups between the hightest
194 capture so far and the currrent group as "unset". Thus, the ovector for
195 those groups contained whatever was previously there. An example is the
196 pattern /(x)|((*ACCEPT))/ when matched against "abcd".
198 2. If an assertion condition was quantified with a minimum of zero (an odd
199 thing to do, but it happened), SIGSEGV or other misbehaviour could occur.
201 3. If a pattern in pcretest input had the P (POSIX) modifier followed by an
202 unrecognized modifier, a crash could occur.
204 4. An attempt to do global matching in pcretest with a zero-length ovector
205 caused a crash.
207 5. Fixed a memory leak during matching that could occur for a subpattern
208 subroutine call (recursive or otherwise) if the number of captured groups
209 that had to be saved was greater than ten.
211 6. Catch a bad opcode during auto-possessification after compiling a bad UTF
212 string with NO_UTF_CHECK. This is a tidyup, not a bug fix, as passing bad
213 UTF with NO_UTF_CHECK is documented as having an undefined outcome.
215 7. A UTF pattern containing a "not" match of a non-ASCII character and a
216 subroutine reference could loop at compile time. Example: /[^\xff]((?1))/.
218 8. When a pattern is compiled, it remembers the highest back reference so that
219 when matching, if the ovector is too small, extra memory can be obtained to
220 use instead. A conditional subpattern whose condition is a check on a
221 capture having happened, such as, for example in the pattern
222 /^(?:(a)|b)(?(1)A|B)/, is another kind of back reference, but it was not
223 setting the highest backreference number. This mattered only if pcre_exec()
224 was called with an ovector that was too small to hold the capture, and there
225 was no other kind of back reference (a situation which is probably quite
226 rare). The effect of the bug was that the condition was always treated as
227 FALSE when the capture could not be consulted, leading to a incorrect
228 behaviour by pcre_exec(). This bug has been fixed.
230 9. A reference to a duplicated named group (either a back reference or a test
231 for being set in a conditional) that occurred in a part of the pattern where
232 PCRE_DUPNAMES was not set caused the amount of memory needed for the pattern
233 to be incorrectly calculated, leading to overwriting.
235 10. A mutually recursive set of back references such as (\2)(\1) caused a
236 segfault at study time (while trying to find the minimum matching length).
237 The infinite loop is now broken (with the minimum length unset, that is,
238 zero).
240 11. If an assertion that was used as a condition was quantified with a minimum
241 of zero, matching went wrong. In particular, if the whole group had
242 unlimited repetition and could match an empty string, a segfault was
243 likely. The pattern (?(?=0)?)+ is an example that caused this. Perl allows
244 assertions to be quantified, but not if they are being used as conditions,
245 so the above pattern is faulted by Perl. PCRE has now been changed so that
246 it also rejects such patterns.
248 12. A possessive capturing group such as (a)*+ with a minimum repeat of zero
249 failed to allow the zero-repeat case if pcre2_exec() was called with an
250 ovector too small to capture the group.
252 13. Fixed two bugs in pcretest that were discovered by fuzzing and reported by
253 Red Hat Product Security:
255 (a) A crash if /K and /F were both set with the option to save the compiled
256 pattern.
258 (b) Another crash if the option to print captured substrings in a callout
259 was combined with setting a null ovector, for example \O\C+ as a subject
260 string.
262 14. A pattern such as "((?2){0,1999}())?", which has a group containing a
263 forward reference repeated a large (but limited) number of times within a
264 repeated outer group that has a zero minimum quantifier, caused incorrect
265 code to be compiled, leading to the error "internal error:
266 previously-checked referenced subpattern not found" when an incorrect
267 memory address was read. This bug was reported as "heap overflow",
268 discovered by Kai Lu of Fortinet's FortiGuard Labs and given the CVE number
269 CVE-2015-2325.
271 23. A pattern such as "((?+1)(\1))/" containing a forward reference subroutine
272 call within a group that also contained a recursive back reference caused
273 incorrect code to be compiled. This bug was reported as "heap overflow",
274 discovered by Kai Lu of Fortinet's FortiGuard Labs, and given the CVE
275 number CVE-2015-2326.
277 24. Computing the size of the JIT read-only data in advance has been a source
278 of various issues, and new ones are still appear unfortunately. To fix
279 existing and future issues, size computation is eliminated from the code,
280 and replaced by on-demand memory allocation.
282 25. A pattern such as /(?i)[A-`]/, where characters in the other case are
283 adjacent to the end of the range, and the range contained characters with
284 more than one other case, caused incorrect behaviour when compiled in UTF
285 mode. In that example, the range a-j was left out of the class.
287 26. Fix JIT compilation of conditional blocks, which assertion
288 is converted to (*FAIL). E.g: /(?(?!))/.
290 27. The pattern /(?(?!)^)/ caused references to random memory. This bug was
291 discovered by the LLVM fuzzer.
293 28. The assertion (?!) is optimized to (*FAIL). This was not handled correctly
294 when this assertion was used as a condition, for example (?(?!)a|b). In
295 pcre2_match() it worked by luck; in pcre2_dfa_match() it gave an incorrect
296 error about an unsupported item.
298 29. For some types of pattern, for example /Z*(|d*){216}/, the auto-
299 possessification code could take exponential time to complete. A recursion
300 depth limit of 1000 has been imposed to limit the resources used by this
301 optimization.
303 30. A pattern such as /(*UTF)[\S\V\H]/, which contains a negated special class
304 such as \S in non-UCP mode, explicit wide characters (> 255) can be ignored
305 because \S ensures they are all in the class. The code for doing this was
306 interacting badly with the code for computing the amount of space needed to
307 compile the pattern, leading to a buffer overflow. This bug was discovered
308 by the LLVM fuzzer.
310 31. A pattern such as /((?2)+)((?1))/ which has mutual recursion nested inside
311 other kinds of group caused stack overflow at compile time. This bug was
312 discovered by the LLVM fuzzer.
314 32. A pattern such as /(?1)(?#?'){8}(a)/ which had a parenthesized comment
315 between a subroutine call and its quantifier was incorrectly compiled,
316 leading to buffer overflow or other errors. This bug was discovered by the
317 LLVM fuzzer.
319 33. The illegal pattern /(?(?<E>.*!.*)?)/ was not being diagnosed as missing an
320 assertion after (?(. The code was failing to check the character after
321 (?(?< for the ! or = that would indicate a lookbehind assertion. This bug
322 was discovered by the LLVM fuzzer.
324 34. A pattern such as /X((?2)()*+){2}+/ which has a possessive quantifier with
325 a fixed maximum following a group that contains a subroutine reference was
326 incorrectly compiled and could trigger buffer overflow. This bug was
327 discovered by the LLVM fuzzer.
329 35. A mutual recursion within a lookbehind assertion such as (?<=((?2))((?1)))
330 caused a stack overflow instead of the diagnosis of a non-fixed length
331 lookbehind assertion. This bug was discovered by the LLVM fuzzer.
333 36. The use of \K in a positive lookbehind assertion in a non-anchored pattern
334 (e.g. /(?<=\Ka)/) could make pcregrep loop.
336 37. There was a similar problem to 36 in pcretest for global matches.
338 38. If a greedy quantified \X was preceded by \C in UTF mode (e.g. \C\X*),
339 and a subsequent item in the pattern caused a non-match, backtracking over
340 the repeated \X did not stop, but carried on past the start of the subject,
341 causing reference to random memory and/or a segfault. There were also some
342 other cases where backtracking after \C could crash. This set of bugs was
343 discovered by the LLVM fuzzer.
345 39. The function for finding the minimum length of a matching string could take
346 a very long time if mutual recursion was present many times in a pattern,
347 for example, /((?2){73}(?2))((?1))/. A better mutual recursion detection
348 method has been implemented. This infelicity was discovered by the LLVM
349 fuzzer.
351 40. Static linking against the PCRE library using the pkg-config module was
352 failing on missing pthread symbols.
355 Version 8.36 26-September-2014
356 ------------------------------
358 1. Got rid of some compiler warnings in the C++ modules that were shown up by
359 -Wmissing-field-initializers and -Wunused-parameter.
361 2. The tests for quantifiers being too big (greater than 65535) were being
362 applied after reading the number, and stupidly assuming that integer
363 overflow would give a negative number. The tests are now applied as the
364 numbers are read.
366 3. Tidy code in pcre_exec.c where two branches that used to be different are
367 now the same.
369 4. The JIT compiler did not generate match limit checks for certain
370 bracketed expressions with quantifiers. This may lead to exponential
371 backtracking, instead of returning with PCRE_ERROR_MATCHLIMIT. This
372 issue should be resolved now.
374 5. Fixed an issue, which occures when nested alternatives are optimized
375 with table jumps.
377 6. Inserted two casts and changed some ints to size_t in the light of some
378 reported 64-bit compiler warnings (Bugzilla 1477).
380 7. Fixed a bug concerned with zero-minimum possessive groups that could match
381 an empty string, which sometimes were behaving incorrectly in the
382 interpreter (though correctly in the JIT matcher). This pcretest input is
383 an example:
385 '\A(?:[^"]++|"(?:[^"]*+|"")*+")++'
388 the interpreter was reporting a match of 'NON QUOTED ' only, whereas the
389 JIT matcher and Perl both matched 'NON QUOTED "QUOT""ED" AFTER '. The test
390 for an empty string was breaking the inner loop and carrying on at a lower
391 level, when possessive repeated groups should always return to a higher
392 level as they have no backtrack points in them. The empty string test now
393 occurs at the outer level.
395 8. Fixed a bug that was incorrectly auto-possessifying \w+ in the pattern
396 ^\w+(?>\s*)(?<=\w) which caused it not to match "test test".
398 9. Give a compile-time error for \o{} (as Perl does) and for \x{} (which Perl
399 doesn't).
401 10. Change 8.34/15 introduced a bug that caused the amount of memory needed
402 to hold a pattern to be incorrectly computed (too small) when there were
403 named back references to duplicated names. This could cause "internal
404 error: code overflow" or "double free or corruption" or other memory
405 handling errors.
407 11. When named subpatterns had the same prefixes, back references could be
408 confused. For example, in this pattern:
410 /(?P<Name>a)?(?P<Name2>b)?(?(<Name>)c|d)*l/
412 the reference to 'Name' was incorrectly treated as a reference to a
413 duplicate name.
415 12. A pattern such as /^s?c/mi8 where the optional character has more than
416 one "other case" was incorrectly compiled such that it would only try to
417 match starting at "c".
419 13. When a pattern starting with \s was studied, VT was not included in the
420 list of possible starting characters; this should have been part of the
421 8.34/18 patch.
423 14. If a character class started [\Qx]... where x is any character, the class
424 was incorrectly terminated at the ].
426 15. If a pattern that started with a caseless match for a character with more
427 than one "other case" was studied, PCRE did not set up the starting code
428 unit bit map for the list of possible characters. Now it does. This is an
429 optimization improvement, not a bug fix.
431 16. The Unicode data tables have been updated to Unicode 7.0.0.
433 17. Fixed a number of memory leaks in pcregrep.
435 18. Avoid a compiler warning (from some compilers) for a function call with
436 a cast that removes "const" from an lvalue by using an intermediate
437 variable (to which the compiler does not object).
439 19. Incorrect code was compiled if a group that contained an internal recursive
440 back reference was optional (had quantifier with a minimum of zero). This
441 example compiled incorrect code: /(((a\2)|(a*)\g<-1>))*/ and other examples
442 caused segmentation faults because of stack overflows at compile time.
444 20. A pattern such as /((?(R)a|(?1)))+/, which contains a recursion within a
445 group that is quantified with an indefinite repeat, caused a compile-time
446 loop which used up all the system stack and provoked a segmentation fault.
447 This was not the same bug as 19 above.
449 21. Add PCRECPP_EXP_DECL declaration to operator<< in pcre_stringpiece.h.
450 Patch by Mike Frysinger.
453 Version 8.35 04-April-2014
454 --------------------------
456 1. A new flag is set, when property checks are present in an XCLASS.
457 When this flag is not set, PCRE can perform certain optimizations
458 such as studying these XCLASS-es.
460 2. The auto-possessification of character sets were improved: a normal
461 and an extended character set can be compared now. Furthermore
462 the JIT compiler optimizes more character set checks.
464 3. Got rid of some compiler warnings for potentially uninitialized variables
465 that show up only when compiled with -O2.
467 4. A pattern such as (?=ab\K) that uses \K in an assertion can set the start
468 of a match later then the end of the match. The pcretest program was not
469 handling the case sensibly - it was outputting from the start to the next
470 binary zero. It now reports this situation in a message, and outputs the
471 text from the end to the start.
473 5. Fast forward search is improved in JIT. Instead of the first three
474 characters, any three characters with fixed position can be searched.
475 Search order: first, last, middle.
477 6. Improve character range checks in JIT. Characters are read by an inprecise
478 function now, which returns with an unknown value if the character code is
479 above a certain threshold (e.g: 256). The only limitation is that the value
480 must be bigger than the threshold as well. This function is useful when
481 the characters above the threshold are handled in the same way.
483 7. The macros whose names start with RAWUCHAR are placeholders for a future
484 mode in which only the bottom 21 bits of 32-bit data items are used. To
485 make this more memorable for those maintaining the code, the names have
486 been changed to start with UCHAR21, and an extensive comment has been added
487 to their definition.
489 8. Add missing (new) files sljitNativeTILEGX.c and sljitNativeTILEGX-encoder.c
490 to the export list in Makefile.am (they were accidentally omitted from the
491 8.34 tarball).
493 9. The informational output from pcretest used the phrase "starting byte set"
494 which is inappropriate for the 16-bit and 32-bit libraries. As the output
495 for "first char" and "need char" really means "non-UTF-char", I've changed
496 "byte" to "char", and slightly reworded the output. The documentation about
497 these values has also been (I hope) clarified.
499 10. Another JIT related optimization: use table jumps for selecting the correct
500 backtracking path, when more than four alternatives are present inside a
501 bracket.
503 11. Empty match is not possible, when the minimum length is greater than zero,
504 and there is no \K in the pattern. JIT should avoid empty match checks in
505 such cases.
507 12. In a caseless character class with UCP support, when a character with more
508 than one alternative case was not the first character of a range, not all
509 the alternative cases were added to the class. For example, s and \x{17f}
510 are both alternative cases for S: the class [RST] was handled correctly,
511 but [R-T] was not.
513 13. The configure.ac file always checked for pthread support when JIT was
514 enabled. This is not used in Windows, so I have put this test inside a
515 check for the presence of windows.h (which was already tested for).
517 14. Improve pattern prefix search by a simplified Boyer-Moore algorithm in JIT.
518 The algorithm provides a way to skip certain starting offsets, and usually
519 faster than linear prefix searches.
521 15. Change 13 for 8.20 updated RunTest to check for the 'fr' locale as well
522 as for 'fr_FR' and 'french'. For some reason, however, it then used the
523 Windows-specific input and output files, which have 'french' screwed in.
524 So this could never have worked. One of the problems with locales is that
525 they aren't always the same. I have now updated RunTest so that it checks
526 the output of the locale test (test 3) against three different output
527 files, and it allows the test to pass if any one of them matches. With luck
528 this should make the test pass on some versions of Solaris where it was
529 failing. Because of the uncertainty, the script did not used to stop if
530 test 3 failed; it now does. If further versions of a French locale ever
531 come to light, they can now easily be added.
533 16. If --with-pcregrep-bufsize was given a non-integer value such as "50K",
534 there was a message during ./configure, but it did not stop. This now
535 provokes an error. The invalid example in README has been corrected.
536 If a value less than the minimum is given, the minimum value has always
537 been used, but now a warning is given.
539 17. If --enable-bsr-anycrlf was set, the special 16/32-bit test failed. This
540 was a bug in the test system, which is now fixed. Also, the list of various
541 configurations that are tested for each release did not have one with both
542 16/32 bits and --enable-bar-anycrlf. It now does.
544 18. pcretest was missing "-C bsr" for displaying the \R default setting.
546 19. Little endian PowerPC systems are supported now by the JIT compiler.
548 20. The fast forward newline mechanism could enter to an infinite loop on
549 certain invalid UTF-8 input. Although we don't support these cases
550 this issue can be fixed by a performance optimization.
552 21. Change 33 of 8.34 is not sufficient to ensure stack safety because it does
553 not take account if existing stack usage. There is now a new global
554 variable called pcre_stack_guard that can be set to point to an external
555 function to check stack availability. It is called at the start of
556 processing every parenthesized group.
558 22. A typo in the code meant that in ungreedy mode the max/min qualifier
559 behaved like a min-possessive qualifier, and, for example, /a{1,3}b/U did
560 not match "ab".
562 23. When UTF was disabled, the JIT program reported some incorrect compile
563 errors. These messages are silenced now.
565 24. Experimental support for ARM-64 and MIPS-64 has been added to the JIT
566 compiler.
568 25. Change all the temporary files used in RunGrepTest to be different to those
569 used by RunTest so that the tests can be run simultaneously, for example by
570 "make -j check".
573 Version 8.34 15-December-2013
574 -----------------------------
576 1. Add pcre[16|32]_jit_free_unused_memory to forcibly free unused JIT
577 executable memory. Patch inspired by Carsten Klein.
579 2. ./configure --enable-coverage defined SUPPORT_GCOV in config.h, although
580 this macro is never tested and has no effect, because the work to support
581 coverage involves only compiling and linking options and special targets in
582 the Makefile. The comment in config.h implied that defining the macro would
583 enable coverage support, which is totally false. There was also support for
584 setting this macro in the CMake files (my fault, I just copied it from
585 configure). SUPPORT_GCOV has now been removed.
587 3. Make a small performance improvement in strlen16() and strlen32() in
588 pcretest.
590 4. Change 36 for 8.33 left some unreachable statements in pcre_exec.c,
591 detected by the Solaris compiler (gcc doesn't seem to be able to diagnose
592 these cases). There was also one in pcretest.c.
594 5. Cleaned up a "may be uninitialized" compiler warning in pcre_exec.c.
596 6. In UTF mode, the code for checking whether a group could match an empty
597 string (which is used for indefinitely repeated groups to allow for
598 breaking an infinite loop) was broken when the group contained a repeated
599 negated single-character class with a character that occupied more than one
600 data item and had a minimum repetition of zero (for example, [^\x{100}]* in
601 UTF-8 mode). The effect was undefined: the group might or might not be
602 deemed as matching an empty string, or the program might have crashed.
604 7. The code for checking whether a group could match an empty string was not
605 recognizing that \h, \H, \v, \V, and \R must match a character.
607 8. Implemented PCRE_INFO_MATCH_EMPTY, which yields 1 if the pattern can match
608 an empty string. If it can, pcretest shows this in its information output.
610 9. Fixed two related bugs that applied to Unicode extended grapheme clusters
611 that were repeated with a maximizing qualifier (e.g. \X* or \X{2,5}) when
612 matched by pcre_exec() without using JIT:
614 (a) If the rest of the pattern did not match after a maximal run of
615 grapheme clusters, the code for backing up to try with fewer of them
616 did not always back up over a full grapheme when characters that do not
617 have the modifier quality were involved, e.g. Hangul syllables.
619 (b) If the match point in a subject started with modifier character, and
620 there was no match, the code could incorrectly back up beyond the match
621 point, and potentially beyond the first character in the subject,
622 leading to a segfault or an incorrect match result.
624 10. A conditional group with an assertion condition could lead to PCRE
625 recording an incorrect first data item for a match if no other first data
626 item was recorded. For example, the pattern (?(?=ab)ab) recorded "a" as a
627 first data item, and therefore matched "ca" after "c" instead of at the
628 start.
630 11. Change 40 for 8.33 (allowing pcregrep to find empty strings) showed up a
631 bug that caused the command "echo a | ./pcregrep -M '|a'" to loop.
633 12. The source of pcregrep now includes z/OS-specific code so that it can be
634 compiled for z/OS as part of the special z/OS distribution.
636 13. Added the -T and -TM options to pcretest.
638 14. The code in pcre_compile.c for creating the table of named capturing groups
639 has been refactored. Instead of creating the table dynamically during the
640 actual compiling pass, the information is remembered during the pre-compile
641 pass (on the stack unless there are more than 20 named groups, in which
642 case malloc() is used) and the whole table is created before the actual
643 compile happens. This has simplified the code (it is now nearly 150 lines
644 shorter) and prepared the way for better handling of references to groups
645 with duplicate names.
647 15. A back reference to a named subpattern when there is more than one of the
648 same name now checks them in the order in which they appear in the pattern.
649 The first one that is set is used for the reference. Previously only the
650 first one was inspected. This change makes PCRE more compatible with Perl.
652 16. Unicode character properties were updated from Unicode 6.3.0.
654 17. The compile-time code for auto-possessification has been refactored, based
655 on a patch by Zoltan Herczeg. It now happens after instead of during
656 compilation. The code is cleaner, and more cases are handled. The option
657 PCRE_NO_AUTO_POSSESS is added for testing purposes, and the -O and /O
658 options in pcretest are provided to set it. It can also be set by
659 (*NO_AUTO_POSSESS) at the start of a pattern.
661 18. The character VT has been added to the default ("C" locale) set of
662 characters that match \s and are generally treated as white space,
663 following this same change in Perl 5.18. There is now no difference between
664 "Perl space" and "POSIX space". Whether VT is treated as white space in
665 other locales depends on the locale.
667 19. The code for checking named groups as conditions, either for being set or
668 for being recursed, has been refactored (this is related to 14 and 15
669 above). Processing unduplicated named groups should now be as fast at
670 numerical groups, and processing duplicated groups should be faster than
671 before.
673 20. Two patches to the CMake build system, by Alexander Barkov:
675 (1) Replace the "source" command by "." in CMakeLists.txt because
676 "source" is a bash-ism.
678 (2) Add missing HAVE_STDINT_H and HAVE_INTTYPES_H to config-cmake.h.in;
679 without these the CMake build does not work on Solaris.
681 21. Perl has changed its handling of \8 and \9. If there is no previously
682 encountered capturing group of those numbers, they are treated as the
683 literal characters 8 and 9 instead of a binary zero followed by the
684 literals. PCRE now does the same.
686 22. Following Perl, added \o{} to specify codepoints in octal, making it
687 possible to specify values greater than 0777 and also making them
688 unambiguous.
690 23. Perl now gives an error for missing closing braces after \x{... instead of
691 treating the string as literal. PCRE now does the same.
693 24. RunTest used to grumble if an inappropriate test was selected explicitly,
694 but just skip it when running all tests. This make it awkward to run ranges
695 of tests when one of them was inappropriate. Now it just skips any
696 inappropriate tests, as it always did when running all tests.
698 25. If PCRE_AUTO_CALLOUT and PCRE_UCP were set for a pattern that contained
699 character types such as \d or \w, too many callouts were inserted, and the
700 data that they returned was rubbish.
702 26. In UCP mode, \s was not matching two of the characters that Perl matches,
703 namely NEL (U+0085) and MONGOLIAN VOWEL SEPARATOR (U+180E), though they
704 were matched by \h. The code has now been refactored so that the lists of
705 the horizontal and vertical whitespace characters used for \h and \v (which
706 are defined only in one place) are now also used for \s.
708 27. Add JIT support for the 64 bit TileGX architecture.
709 Patch by Jiong Wang (Tilera Corporation).
711 28. Possessive quantifiers for classes (both explicit and automatically
712 generated) now use special opcodes instead of wrapping in ONCE brackets.
714 29. Whereas an item such as A{4}+ ignored the possessivenes of the quantifier
715 (because it's meaningless), this was not happening when PCRE_CASELESS was
716 set. Not wrong, but inefficient.
718 30. Updated perltest.pl to add /u (force Unicode mode) when /W (use Unicode
719 properties for \w, \d, etc) is present in a test regex. Otherwise if the
720 test contains no characters greater than 255, Perl doesn't realise it
721 should be using Unicode semantics.
723 31. Upgraded the handling of the POSIX classes [:graph:], [:print:], and
724 [:punct:] when PCRE_UCP is set so as to include the same characters as Perl
725 does in Unicode mode.
727 32. Added the "forbid" facility to pcretest so that putting tests into the
728 wrong test files can sometimes be quickly detected.
730 33. There is now a limit (default 250) on the depth of nesting of parentheses.
731 This limit is imposed to control the amount of system stack used at compile
732 time. It can be changed at build time by --with-parens-nest-limit=xxx or
733 the equivalent in CMake.
735 34. Character classes such as [A-\d] or [a-[:digit:]] now cause compile-time
736 errors. Perl warns for these when in warning mode, but PCRE has no facility
737 for giving warnings.
739 35. Change 34 for 8.13 allowed quantifiers on assertions, because Perl does.
740 However, this was not working for (?!) because it is optimized to (*FAIL),
741 for which PCRE does not allow quantifiers. The optimization is now disabled
742 when a quantifier follows (?!). I can't see any use for this, but it makes
743 things uniform.
745 36. Perl no longer allows group names to start with digits, so I have made this
746 change also in PCRE. It simplifies the code a bit.
748 37. In extended mode, Perl ignores spaces before a + that indicates a
749 possessive quantifier. PCRE allowed a space before the quantifier, but not
750 before the possessive +. It now does.
752 38. The use of \K (reset reported match start) within a repeated possessive
753 group such as (a\Kb)*+ was not working.
755 40. Document that the same character tables must be used at compile time and
756 run time, and that the facility to pass tables to pcre_exec() and
757 pcre_dfa_exec() is for use only with saved/restored patterns.
759 41. Applied Jeff Trawick's patch CMakeLists.txt, which "provides two new
760 features for Builds with MSVC:
762 1. Support pcre.rc and/or pcreposix.rc (as is already done for MinGW
763 builds). The .rc files can be used to set FileDescription and many other
764 attributes.
766 2. Add an option (-DINSTALL_MSVC_PDB) to enable installation of .pdb files.
767 This allows higher-level build scripts which want .pdb files to avoid
768 hard-coding the exact files needed."
770 42. Added support for [[:<:]] and [[:>:]] as used in the BSD POSIX library to
771 mean "start of word" and "end of word", respectively, as a transition aid.
773 43. A minimizing repeat of a class containing codepoints greater than 255 in
774 non-UTF 16-bit or 32-bit modes caused an internal error when PCRE was
775 compiled to use the heap for recursion.
777 44. Got rid of some compiler warnings for unused variables when UTF but not UCP
778 is configured.
781 Version 8.33 28-May-2013
782 ------------------------
784 1. Added 'U' to some constants that are compared to unsigned integers, to
785 avoid compiler signed/unsigned warnings. Added (int) casts to unsigned
786 variables that are added to signed variables, to ensure the result is
787 signed and can be negated.
789 2. Applied patch by Daniel Richard G for quashing MSVC warnings to the
790 CMake config files.
792 3. Revise the creation of config.h.generic so that all boolean macros are
793 #undefined, whereas non-boolean macros are #ifndef/#endif-ed. This makes
794 overriding via -D on the command line possible.
796 4. Changing the definition of the variable "op" in pcre_exec.c from pcre_uchar
797 to unsigned int is reported to make a quite noticeable speed difference in
798 a specific Windows environment. Testing on Linux did also appear to show
799 some benefit (and it is clearly not harmful). Also fixed the definition of
800 Xop which should be unsigned.
802 5. Related to (4), changing the definition of the intermediate variable cc
803 in repeated character loops from pcre_uchar to pcre_uint32 also gave speed
804 improvements.
806 6. Fix forward search in JIT when link size is 3 or greater. Also removed some
807 unnecessary spaces.
809 7. Adjust autogen.sh and configure.ac to lose warnings given by automake 1.12
810 and later.
812 8. Fix two buffer over read issues in 16 and 32 bit modes. Affects JIT only.
814 9. Optimizing fast_forward_start_bits in JIT.
816 10. Adding support for callouts in JIT, and fixing some issues revealed
817 during this work. Namely:
819 (a) Unoptimized capturing brackets incorrectly reset on backtrack.
821 (b) Minimum length was not checked before the matching is started.
823 11. The value of capture_last that is passed to callouts was incorrect in some
824 cases when there was a capture on one path that was subsequently abandoned
825 after a backtrack. Also, the capture_last value is now reset after a
826 recursion, since all captures are also reset in this case.
828 12. The interpreter no longer returns the "too many substrings" error in the
829 case when an overflowing capture is in a branch that is subsequently
830 abandoned after a backtrack.
832 13. In the pathological case when an offset vector of size 2 is used, pcretest
833 now prints out the matched string after a yield of 0 or 1.
835 14. Inlining subpatterns in recursions, when certain conditions are fulfilled.
836 Only supported by the JIT compiler at the moment.
838 15. JIT compiler now supports 32 bit Macs thanks to Lawrence Velazquez.
840 16. Partial matches now set offsets[2] to the "bumpalong" value, that is, the
841 offset of the starting point of the matching process, provided the offsets
842 vector is large enough.
844 17. The \A escape now records a lookbehind value of 1, though its execution
845 does not actually inspect the previous character. This is to ensure that,
846 in partial multi-segment matching, at least one character from the old
847 segment is retained when a new segment is processed. Otherwise, if there
848 are no lookbehinds in the pattern, \A might match incorrectly at the start
849 of a new segment.
851 18. Added some #ifdef __VMS code into pcretest.c to help VMS implementations.
853 19. Redefined some pcre_uchar variables in pcre_exec.c as pcre_uint32; this
854 gives some modest performance improvement in 8-bit mode.
856 20. Added the PCRE-specific property \p{Xuc} for matching characters that can
857 be expressed in certain programming languages using Universal Character
858 Names.
860 21. Unicode validation has been updated in the light of Unicode Corrigendum #9,
861 which points out that "non characters" are not "characters that may not
862 appear in Unicode strings" but rather "characters that are reserved for
863 internal use and have only local meaning".
865 22. When a pattern was compiled with automatic callouts (PCRE_AUTO_CALLOUT) and
866 there was a conditional group that depended on an assertion, if the
867 assertion was false, the callout that immediately followed the alternation
868 in the condition was skipped when pcre_exec() was used for matching.
870 23. Allow an explicit callout to be inserted before an assertion that is the
871 condition for a conditional group, for compatibility with automatic
872 callouts, which always insert a callout at this point.
874 24. In 8.31, (*COMMIT) was confined to within a recursive subpattern. Perl also
875 confines (*SKIP) and (*PRUNE) in the same way, and this has now been done.
877 25. (*PRUNE) is now supported by the JIT compiler.
879 26. Fix infinite loop when /(?<=(*SKIP)ac)a/ is matched against aa.
881 27. Fix the case where there are two or more SKIPs with arguments that may be
882 ignored.
884 28. (*SKIP) is now supported by the JIT compiler.
886 29. (*THEN) is now supported by the JIT compiler.
888 30. Update RunTest with additional test selector options.
890 31. The way PCRE handles backtracking verbs has been changed in two ways.
892 (1) Previously, in something like (*COMMIT)(*SKIP), COMMIT would override
893 SKIP. Now, PCRE acts on whichever backtracking verb is reached first by
894 backtracking. In some cases this makes it more Perl-compatible, but Perl's
895 rather obscure rules do not always do the same thing.
897 (2) Previously, backtracking verbs were confined within assertions. This is
898 no longer the case for positive assertions, except for (*ACCEPT). Again,
899 this sometimes improves Perl compatibility, and sometimes does not.
901 32. A number of tests that were in test 2 because Perl did things differently
902 have been moved to test 1, because either Perl or PCRE has changed, and
903 these tests are now compatible.
905 32. Backtracking control verbs are now handled in the same way in JIT and
906 interpreter.
908 33. An opening parenthesis in a MARK/PRUNE/SKIP/THEN name in a pattern that
909 contained a forward subroutine reference caused a compile error.
911 34. Auto-detect and optimize limited repetitions in JIT.
913 35. Implement PCRE_NEVER_UTF to lock out the use of UTF, in particular,
914 blocking (*UTF) etc.
916 36. In the interpreter, maximizing pattern repetitions for characters and
917 character types now use tail recursion, which reduces stack usage.
919 37. The value of the max lookbehind was not correctly preserved if a compiled
920 and saved regex was reloaded on a host of different endianness.
922 38. Implemented (*LIMIT_MATCH) and (*LIMIT_RECURSION). As part of the extension
923 of the compiled pattern block, expand the flags field from 16 to 32 bits
924 because it was almost full.
926 39. Try madvise first before posix_madvise.
928 40. Change 7 for PCRE 7.9 made it impossible for pcregrep to find empty lines
929 with a pattern such as ^$. It has taken 4 years for anybody to notice! The
930 original change locked out all matches of empty strings. This has been
931 changed so that one match of an empty string per line is recognized.
932 Subsequent searches on the same line (for colouring or for --only-matching,
933 for example) do not recognize empty strings.
935 41. Applied a user patch to fix a number of spelling mistakes in comments.
937 42. Data lines longer than 65536 caused pcretest to crash.
939 43. Clarified the data type for length and startoffset arguments for pcre_exec
940 and pcre_dfa_exec in the function-specific man pages, where they were
941 explicitly stated to be in bytes, never having been updated. I also added
942 some clarification to the pcreapi man page.
944 44. A call to pcre_dfa_exec() with an output vector size less than 2 caused
945 a segmentation fault.
948 Version 8.32 30-November-2012
949 -----------------------------
951 1. Improved JIT compiler optimizations for first character search and single
952 character iterators.
954 2. Supporting IBM XL C compilers for PPC architectures in the JIT compiler.
955 Patch by Daniel Richard G.
957 3. Single character iterator optimizations in the JIT compiler.
959 4. Improved JIT compiler optimizations for character ranges.
961 5. Rename the "leave" variable names to "quit" to improve WinCE compatibility.
962 Reported by Giuseppe D'Angelo.
964 6. The PCRE_STARTLINE bit, indicating that a match can occur only at the start
965 of a line, was being set incorrectly in cases where .* appeared inside
966 atomic brackets at the start of a pattern, or where there was a subsequent
967 *PRUNE or *SKIP.
969 7. Improved instruction cache flush for POWER/PowerPC.
970 Patch by Daniel Richard G.
972 8. Fixed a number of issues in pcregrep, making it more compatible with GNU
973 grep:
975 (a) There is now no limit to the number of patterns to be matched.
977 (b) An error is given if a pattern is too long.
979 (c) Multiple uses of --exclude, --exclude-dir, --include, and --include-dir
980 are now supported.
982 (d) --exclude-from and --include-from (multiple use) have been added.
984 (e) Exclusions and inclusions now apply to all files and directories, not
985 just to those obtained from scanning a directory recursively.
987 (f) Multiple uses of -f and --file-list are now supported.
989 (g) In a Windows environment, the default for -d has been changed from
990 "read" (the GNU grep default) to "skip", because otherwise the presence
991 of a directory in the file list provokes an error.
993 (h) The documentation has been revised and clarified in places.
995 9. Improve the matching speed of capturing brackets.
997 10. Changed the meaning of \X so that it now matches a Unicode extended
998 grapheme cluster.
1000 11. Patch by Daniel Richard G to the autoconf files to add a macro for sorting
1001 out POSIX threads when JIT support is configured.
1003 12. Added support for PCRE_STUDY_EXTRA_NEEDED.
1005 13. In the POSIX wrapper regcomp() function, setting re_nsub field in the preg
1006 structure could go wrong in environments where size_t is not the same size
1007 as int.
1009 14. Applied user-supplied patch to pcrecpp.cc to allow PCRE_NO_UTF8_CHECK to be
1010 set.
1012 15. The EBCDIC support had decayed; later updates to the code had included
1013 explicit references to (e.g.) \x0a instead of CHAR_LF. There has been a
1014 general tidy up of EBCDIC-related issues, and the documentation was also
1015 not quite right. There is now a test that can be run on ASCII systems to
1016 check some of the EBCDIC-related things (but is it not a full test).
1018 16. The new PCRE_STUDY_EXTRA_NEEDED option is now used by pcregrep, resulting
1019 in a small tidy to the code.
1021 17. Fix JIT tests when UTF is disabled and both 8 and 16 bit mode are enabled.
1023 18. If the --only-matching (-o) option in pcregrep is specified multiple
1024 times, each one causes appropriate output. For example, -o1 -o2 outputs the
1025 substrings matched by the 1st and 2nd capturing parentheses. A separating
1026 string can be specified by --om-separator (default empty).
1028 19. Improving the first n character searches.
1030 20. Turn case lists for horizontal and vertical white space into macros so that
1031 they are defined only once.
1033 21. This set of changes together give more compatible Unicode case-folding
1034 behaviour for characters that have more than one other case when UCP
1035 support is available.
1037 (a) The Unicode property table now has offsets into a new table of sets of
1038 three or more characters that are case-equivalent. The MultiStage2.py
1039 script that generates these tables (the pcre_ucd.c file) now scans
1040 CaseFolding.txt instead of UnicodeData.txt for character case
1041 information.
1043 (b) The code for adding characters or ranges of characters to a character
1044 class has been abstracted into a generalized function that also handles
1045 case-independence. In UTF-mode with UCP support, this uses the new data
1046 to handle characters with more than one other case.
1048 (c) A bug that is fixed as a result of (b) is that codepoints less than 256
1049 whose other case is greater than 256 are now correctly matched
1050 caselessly. Previously, the high codepoint matched the low one, but not
1051 vice versa.
1053 (d) The processing of \h, \H, \v, and \ in character classes now makes use
1054 of the new class addition function, using character lists defined as
1055 macros alongside the case definitions of 20 above.
1057 (e) Caseless back references now work with characters that have more than
1058 one other case.
1060 (f) General caseless matching of characters with more than one other case
1061 is supported.
1063 22. Unicode character properties were updated from Unicode 6.2.0
1065 23. Improved CMake support under Windows. Patch by Daniel Richard G.
1067 24. Add support for 32-bit character strings, and UTF-32
1069 25. Major JIT compiler update (code refactoring and bugfixing).
1070 Experimental Sparc 32 support is added.
1072 26. Applied a modified version of Daniel Richard G's patch to create
1073 pcre.h.generic and config.h.generic by "make" instead of in the
1074 PrepareRelease script.
1076 27. Added a definition for CHAR_NULL (helpful for the z/OS port), and use it in
1077 pcre_compile.c when checking for a zero character.
1079 28. Introducing a native interface for JIT. Through this interface, the compiled
1080 machine code can be directly executed. The purpose of this interface is to
1081 provide fast pattern matching, so several sanity checks are not performed.
1082 However, feature tests are still performed. The new interface provides
1083 1.4x speedup compared to the old one.
1085 29. If pcre_exec() or pcre_dfa_exec() was called with a negative value for
1086 the subject string length, the error given was PCRE_ERROR_BADOFFSET, which
1087 was confusing. There is now a new error PCRE_ERROR_BADLENGTH for this case.
1089 30. In 8-bit UTF-8 mode, pcretest failed to give an error for data codepoints
1090 greater than 0x7fffffff (which cannot be represented in UTF-8, even under
1091 the "old" RFC 2279). Instead, it ended up passing a negative length to
1092 pcre_exec().
1094 31. Add support for GCC's visibility feature to hide internal functions.
1096 32. Running "pcretest -C pcre8" or "pcretest -C pcre16" gave a spurious error
1097 "unknown -C option" after outputting 0 or 1.
1099 33. There is now support for generating a code coverage report for the test
1100 suite in environments where gcc is the compiler and lcov is installed. This
1101 is mainly for the benefit of the developers.
1103 34. If PCRE is built with --enable-valgrind, certain memory regions are marked
1104 unaddressable using valgrind annotations, allowing valgrind to detect
1105 invalid memory accesses. This is mainly for the benefit of the developers.
1107 25. (*UTF) can now be used to start a pattern in any of the three libraries.
1109 26. Give configure error if --enable-cpp but no C++ compiler found.
1112 Version 8.31 06-July-2012
1113 -------------------------
1115 1. Fixing a wrong JIT test case and some compiler warnings.
1117 2. Removed a bashism from the RunTest script.
1119 3. Add a cast to pcre_exec.c to fix the warning "unary minus operator applied
1120 to unsigned type, result still unsigned" that was given by an MS compiler
1121 on encountering the code "-sizeof(xxx)".
1123 4. Partial matching support is added to the JIT compiler.
1125 5. Fixed several bugs concerned with partial matching of items that consist
1126 of more than one character:
1128 (a) /^(..)\1/ did not partially match "aba" because checking references was
1129 done on an "all or nothing" basis. This also applied to repeated
1130 references.
1132 (b) \R did not give a hard partial match if \r was found at the end of the
1133 subject.
1135 (c) \X did not give a hard partial match after matching one or more
1136 characters at the end of the subject.
1138 (d) When newline was set to CRLF, a pattern such as /a$/ did not recognize
1139 a partial match for the string "\r".
1141 (e) When newline was set to CRLF, the metacharacter "." did not recognize
1142 a partial match for a CR character at the end of the subject string.
1144 6. If JIT is requested using /S++ or -s++ (instead of just /S+ or -s+) when
1145 running pcretest, the text "(JIT)" added to the output whenever JIT is
1146 actually used to run the match.
1148 7. Individual JIT compile options can be set in pcretest by following -s+[+]
1149 or /S+[+] with a digit between 1 and 7.
1151 8. OP_NOT now supports any UTF character not just single-byte ones.
1153 9. (*MARK) control verb is now supported by the JIT compiler.
1155 10. The command "./RunTest list" lists the available tests without actually
1156 running any of them. (Because I keep forgetting what they all are.)
1160 12. Applied a (slightly modified) user-supplied patch that improves performance
1161 when the heap is used for recursion (compiled with --disable-stack-for-
1162 recursion). Instead of malloc and free for each heap frame each time a
1163 logical recursion happens, frames are retained on a chain and re-used where
1164 possible. This sometimes gives as much as 30% improvement.
1166 13. As documented, (*COMMIT) is now confined to within a recursive subpattern
1167 call.
1169 14. As documented, (*COMMIT) is now confined to within a positive assertion.
1171 15. It is now possible to link pcretest with libedit as an alternative to
1172 libreadline.
1174 16. (*COMMIT) control verb is now supported by the JIT compiler.
1176 17. The Unicode data tables have been updated to Unicode 6.1.0.
1178 18. Added --file-list option to pcregrep.
1180 19. Added binary file support to pcregrep, including the -a, --binary-files,
1181 -I, and --text options.
1183 20. The madvise function is renamed for posix_madvise for QNX compatibility
1184 reasons. Fixed by Giuseppe D'Angelo.
1186 21. Fixed a bug for backward assertions with REVERSE 0 in the JIT compiler.
1188 22. Changed the option for creating symbolic links for 16-bit man pages from
1189 -s to -sf so that re-installing does not cause issues.
1191 23. Support PCRE_NO_START_OPTIMIZE in JIT as (*MARK) support requires it.
1193 24. Fixed a very old bug in pcretest that caused errors with restarted DFA
1194 matches in certain environments (the workspace was not being correctly
1195 retained). Also added to pcre_dfa_exec() a simple plausibility check on
1196 some of the workspace data at the beginning of a restart.
1198 25. \s*\R was auto-possessifying the \s* when it should not, whereas \S*\R
1199 was not doing so when it should - probably a typo introduced by SVN 528
1200 (change 8.10/14).
1202 26. When PCRE_UCP was not set, \w+\x{c4} was incorrectly auto-possessifying the
1203 \w+ when the character tables indicated that \x{c4} was a word character.
1204 There were several related cases, all because the tests for doing a table
1205 lookup were testing for characters less than 127 instead of 255.
1207 27. If a pattern contains capturing parentheses that are not used in a match,
1208 their slots in the ovector are set to -1. For those that are higher than
1209 any matched groups, this happens at the end of processing. In the case when
1210 there were back references that the ovector was too small to contain
1211 (causing temporary malloc'd memory to be used during matching), and the
1212 highest capturing number was not used, memory off the end of the ovector
1213 was incorrectly being set to -1. (It was using the size of the temporary
1214 memory instead of the true size.)
1216 28. To catch bugs like 27 using valgrind, when pcretest is asked to specify an
1217 ovector size, it uses memory at the end of the block that it has got.
1219 29. Check for an overlong MARK name and give an error at compile time. The
1220 limit is 255 for the 8-bit library and 65535 for the 16-bit library.
1222 30. JIT compiler update.
1224 31. JIT is now supported on jailbroken iOS devices. Thanks for Ruiger
1225 Rill for the patch.
1227 32. Put spaces around SLJIT_PRINT_D in the JIT compiler. Required by CXX11.
1229 33. Variable renamings in the PCRE-JIT compiler. No functionality change.
1231 34. Fixed typos in pcregrep: in two places there was SUPPORT_LIBZ2 instead of
1232 SUPPORT_LIBBZ2. This caused a build problem when bzip2 but not gzip (zlib)
1233 was enabled.
1235 35. Improve JIT code generation for greedy plus quantifier.
1237 36. When /((?:a?)*)*c/ or /((?>a?)*)*c/ was matched against "aac", it set group
1238 1 to "aa" instead of to an empty string. The bug affected repeated groups
1239 that could potentially match an empty string.
1241 37. Optimizing single character iterators in JIT.
1243 38. Wide characters specified with \uxxxx in JavaScript mode are now subject to
1244 the same checks as \x{...} characters in non-JavaScript mode. Specifically,
1245 codepoints that are too big for the mode are faulted, and in a UTF mode,
1246 disallowed codepoints are also faulted.
1248 39. If PCRE was compiled with UTF support, in three places in the DFA
1249 matcher there was code that should only have been obeyed in UTF mode, but
1250 was being obeyed unconditionally. In 8-bit mode this could cause incorrect
1251 processing when bytes with values greater than 127 were present. In 16-bit
1252 mode the bug would be provoked by values in the range 0xfc00 to 0xdc00. In
1253 both cases the values are those that cannot be the first data item in a UTF
1254 character. The three items that might have provoked this were recursions,
1255 possessively repeated groups, and atomic groups.
1257 40. Ensure that libpcre is explicitly listed in the link commands for pcretest
1258 and pcregrep, because some OS require shared objects to be explicitly
1259 passed to ld, causing the link step to fail if they are not.
1261 41. There were two incorrect #ifdefs in pcre_study.c, meaning that, in 16-bit
1262 mode, patterns that started with \h* or \R* might be incorrectly matched.
1265 Version 8.30 04-February-2012
1266 -----------------------------
1268 1. Renamed "isnumber" as "is_a_number" because in some Mac environments this
1269 name is defined in ctype.h.
1271 2. Fixed a bug in fixed-length calculation for lookbehinds that would show up
1272 only in quite long subpatterns.
1274 3. Removed the function pcre_info(), which has been obsolete and deprecated
1275 since it was replaced by pcre_fullinfo() in February 2000.
1277 4. For a non-anchored pattern, if (*SKIP) was given with a name that did not
1278 match a (*MARK), and the match failed at the start of the subject, a
1279 reference to memory before the start of the subject could occur. This bug
1280 was introduced by fix 17 of release 8.21.
1282 5. A reference to an unset group with zero minimum repetition was giving
1283 totally wrong answers (in non-JavaScript-compatibility mode). For example,
1284 /(another)?(\1?)test/ matched against "hello world test". This bug was
1285 introduced in release 8.13.
1287 6. Add support for 16-bit character strings (a large amount of work involving
1288 many changes and refactorings).
1290 7. RunGrepTest failed on msys because \r\n was replaced by whitespace when the
1291 command "pattern=`printf 'xxx\r\njkl'`" was run. The pattern is now taken
1292 from a file.
1294 8. Ovector size of 2 is also supported by JIT based pcre_exec (the ovector size
1295 rounding is not applied in this particular case).
1297 9. The invalid Unicode surrogate codepoints U+D800 to U+DFFF are now rejected
1298 if they appear, or are escaped, in patterns.
1300 10. Get rid of a number of -Wunused-but-set-variable warnings.
1302 11. The pattern /(?=(*:x))(q|)/ matches an empty string, and returns the mark
1303 "x". The similar pattern /(?=(*:x))((*:y)q|)/ did not return a mark at all.
1304 Oddly, Perl behaves the same way. PCRE has been fixed so that this pattern
1305 also returns the mark "x". This bug applied to capturing parentheses,
1306 non-capturing parentheses, and atomic parentheses. It also applied to some
1307 assertions.
1309 12. Stephen Kelly's patch to CMakeLists.txt allows it to parse the version
1310 information out of configure.ac instead of relying on pcre.h.generic, which
1311 is not stored in the repository.
1313 13. Applied Dmitry V. Levin's patch for a more portable method for linking with
1314 -lreadline.
1316 14. ZH added PCRE_CONFIG_JITTARGET; added its output to pcretest -C.
1318 15. Applied Graycode's patch to put the top-level frame on the stack rather
1319 than the heap when not using the stack for recursion. This gives a
1320 performance improvement in many cases when recursion is not deep.
1322 16. Experimental code added to "pcretest -C" to output the stack frame size.
1325 Version 8.21 12-Dec-2011
1326 ------------------------
1328 1. Updating the JIT compiler.
1330 2. JIT compiler now supports OP_NCREF, OP_RREF and OP_NRREF. New test cases
1331 are added as well.
1333 3. Fix cache-flush issue on PowerPC (It is still an experimental JIT port).
1334 PCRE_EXTRA_TABLES is not suported by JIT, and should be checked before
1335 calling _pcre_jit_exec. Some extra comments are added.
1337 4. (*MARK) settings inside atomic groups that do not contain any capturing
1338 parentheses, for example, (?>a(*:m)), were not being passed out. This bug
1339 was introduced by change 18 for 8.20.
1341 5. Supporting of \x, \U and \u in JavaScript compatibility mode based on the
1342 ECMA-262 standard.
1344 6. Lookbehinds such as (?<=a{2}b) that contained a fixed repetition were
1345 erroneously being rejected as "not fixed length" if PCRE_CASELESS was set.
1346 This bug was probably introduced by change 9 of 8.13.
1348 7. While fixing 6 above, I noticed that a number of other items were being
1349 incorrectly rejected as "not fixed length". This arose partly because newer
1350 opcodes had not been added to the fixed-length checking code. I have (a)
1351 corrected the bug and added tests for these items, and (b) arranged for an
1352 error to occur if an unknown opcode is encountered while checking for fixed
1353 length instead of just assuming "not fixed length". The items that were
1354 rejected were: (*ACCEPT), (*COMMIT), (*FAIL), (*MARK), (*PRUNE), (*SKIP),
1355 (*THEN), \h, \H, \v, \V, and single character negative classes with fixed
1356 repetitions, e.g. [^a]{3}, with and without PCRE_CASELESS.
1358 8. A possessively repeated conditional subpattern such as (?(?=c)c|d)++ was
1359 being incorrectly compiled and would have given unpredicatble results.
1361 9. A possessively repeated subpattern with minimum repeat count greater than
1362 one behaved incorrectly. For example, (A){2,}+ behaved as if it was
1363 (A)(A)++ which meant that, after a subsequent mismatch, backtracking into
1364 the first (A) could occur when it should not.
1366 10. Add a cast and remove a redundant test from the code.
1368 11. JIT should use pcre_malloc/pcre_free for allocation.
1370 12. Updated pcre-config so that it no longer shows -L/usr/lib, which seems
1371 best practice nowadays, and helps with cross-compiling. (If the exec_prefix
1372 is anything other than /usr, -L is still shown).
1374 13. In non-UTF-8 mode, \C is now supported in lookbehinds and DFA matching.
1376 14. Perl does not support \N without a following name in a [] class; PCRE now
1377 also gives an error.
1379 15. If a forward reference was repeated with an upper limit of around 2000,
1380 it caused the error "internal error: overran compiling workspace". The
1381 maximum number of forward references (including repeats) was limited by the
1382 internal workspace, and dependent on the LINK_SIZE. The code has been
1383 rewritten so that the workspace expands (via pcre_malloc) if necessary, and
1384 the default depends on LINK_SIZE. There is a new upper limit (for safety)
1385 of around 200,000 forward references. While doing this, I also speeded up
1386 the filling in of repeated forward references.
1388 16. A repeated forward reference in a pattern such as (a)(?2){2}(.) was
1389 incorrectly expecting the subject to contain another "a" after the start.
1391 17. When (*SKIP:name) is activated without a corresponding (*MARK:name) earlier
1392 in the match, the SKIP should be ignored. This was not happening; instead
1393 the SKIP was being treated as NOMATCH. For patterns such as
1394 /A(*MARK:A)A+(*SKIP:B)Z|AAC/ this meant that the AAC branch was never
1395 tested.
1397 18. The behaviour of (*MARK), (*PRUNE), and (*THEN) has been reworked and is
1398 now much more compatible with Perl, in particular in cases where the result
1399 is a non-match for a non-anchored pattern. For example, if
1400 /b(*:m)f|a(*:n)w/ is matched against "abc", the non-match returns the name
1401 "m", where previously it did not return a name. A side effect of this
1402 change is that for partial matches, the last encountered mark name is
1403 returned, as for non matches. A number of tests that were previously not
1404 Perl-compatible have been moved into the Perl-compatible test files. The
1405 refactoring has had the pleasing side effect of removing one argument from
1406 the match() function, thus reducing its stack requirements.
1408 19. If the /S+ option was used in pcretest to study a pattern using JIT,
1409 subsequent uses of /S (without +) incorrectly behaved like /S+.
1411 21. Retrieve executable code size support for the JIT compiler and fixing
1412 some warnings.
1414 22. A caseless match of a UTF-8 character whose other case uses fewer bytes did
1415 not work when the shorter character appeared right at the end of the
1416 subject string.
1418 23. Added some (int) casts to non-JIT modules to reduce warnings on 64-bit
1419 systems.
1421 24. Added PCRE_INFO_JITSIZE to pass on the value from (21) above, and also
1422 output it when the /M option is used in pcretest.
1424 25. The CheckMan script was not being included in the distribution. Also, added
1425 an explicit "perl" to run Perl scripts from the PrepareRelease script
1426 because this is reportedly needed in Windows.
1428 26. If study data was being save in a file and studying had not found a set of
1429 "starts with" bytes for the pattern, the data written to the file (though
1430 never used) was taken from uninitialized memory and so caused valgrind to
1431 complain.
1433 27. Updated RunTest.bat as provided by Sheri Pierce.
1435 28. Fixed a possible uninitialized memory bug in pcre_jit_compile.c.
1437 29. Computation of memory usage for the table of capturing group names was
1438 giving an unnecessarily large value.
1441 Version 8.20 21-Oct-2011
1442 ------------------------
1444 1. Change 37 of 8.13 broke patterns like [:a]...[b:] because it thought it had
1445 a POSIX class. After further experiments with Perl, which convinced me that
1446 Perl has bugs and confusions, a closing square bracket is no longer allowed
1447 in a POSIX name. This bug also affected patterns with classes that started
1448 with full stops.
1450 2. If a pattern such as /(a)b|ac/ is matched against "ac", there is no
1451 captured substring, but while checking the failing first alternative,
1452 substring 1 is temporarily captured. If the output vector supplied to
1453 pcre_exec() was not big enough for this capture, the yield of the function
1454 was still zero ("insufficient space for captured substrings"). This cannot
1455 be totally fixed without adding another stack variable, which seems a lot
1456 of expense for a edge case. However, I have improved the situation in cases
1457 such as /(a)(b)x|abc/ matched against "abc", where the return code
1458 indicates that fewer than the maximum number of slots in the ovector have
1459 been set.
1461 3. Related to (2) above: when there are more back references in a pattern than
1462 slots in the output vector, pcre_exec() uses temporary memory during
1463 matching, and copies in the captures as far as possible afterwards. It was
1464 using the entire output vector, but this conflicts with the specification
1465 that only 2/3 is used for passing back captured substrings. Now it uses
1466 only the first 2/3, for compatibility. This is, of course, another edge
1467 case.
1469 4. Zoltan Herczeg's just-in-time compiler support has been integrated into the
1470 main code base, and can be used by building with --enable-jit. When this is
1471 done, pcregrep automatically uses it unless --disable-pcregrep-jit or the
1472 runtime --no-jit option is given.
1474 5. When the number of matches in a pcre_dfa_exec() run exactly filled the
1475 ovector, the return from the function was zero, implying that there were
1476 other matches that did not fit. The correct "exactly full" value is now
1477 returned.
1479 6. If a subpattern that was called recursively or as a subroutine contained
1480 (*PRUNE) or any other control that caused it to give a non-standard return,
1481 invalid errors such as "Error -26 (nested recursion at the same subject
1482 position)" or even infinite loops could occur.
1484 7. If a pattern such as /a(*SKIP)c|b(*ACCEPT)|/ was studied, it stopped
1485 computing the minimum length on reaching *ACCEPT, and so ended up with the
1486 wrong value of 1 rather than 0. Further investigation indicates that
1487 computing a minimum subject length in the presence of *ACCEPT is difficult
1488 (think back references, subroutine calls), and so I have changed the code
1489 so that no minimum is registered for a pattern that contains *ACCEPT.
1491 8. If (*THEN) was present in the first (true) branch of a conditional group,
1492 it was not handled as intended. [But see 16 below.]
1494 9. Replaced RunTest.bat and CMakeLists.txt with improved versions provided by
1495 Sheri Pierce.
1497 10. A pathological pattern such as /(*ACCEPT)a/ was miscompiled, thinking that
1498 the first byte in a match must be "a".
1500 11. Change 17 for 8.13 increased the recursion depth for patterns like
1501 /a(?:.)*?a/ drastically. I've improved things by remembering whether a
1502 pattern contains any instances of (*THEN). If it does not, the old
1503 optimizations are restored. It would be nice to do this on a per-group
1504 basis, but at the moment that is not feasible.
1506 12. In some environments, the output of pcretest -C is CRLF terminated. This
1507 broke RunTest's code that checks for the link size. A single white space
1508 character after the value is now allowed for.
1510 13. RunTest now checks for the "fr" locale as well as for "fr_FR" and "french".
1511 For "fr", it uses the Windows-specific input and output files.
1513 14. If (*THEN) appeared in a group that was called recursively or as a
1514 subroutine, it did not work as intended. [But see next item.]
1516 15. Consider the pattern /A (B(*THEN)C) | D/ where A, B, C, and D are complex
1517 pattern fragments (but not containing any | characters). If A and B are
1518 matched, but there is a failure in C so that it backtracks to (*THEN), PCRE
1519 was behaving differently to Perl. PCRE backtracked into A, but Perl goes to
1520 D. In other words, Perl considers parentheses that do not contain any |
1521 characters to be part of a surrounding alternative, whereas PCRE was
1522 treading (B(*THEN)C) the same as (B(*THEN)C|(*FAIL)) -- which Perl handles
1523 differently. PCRE now behaves in the same way as Perl, except in the case
1524 of subroutine/recursion calls such as (?1) which have in any case always
1525 been different (but PCRE had them first :-).
1527 16. Related to 15 above: Perl does not treat the | in a conditional group as
1528 creating alternatives. Such a group is treated in the same way as an
1529 ordinary group without any | characters when processing (*THEN). PCRE has
1530 been changed to match Perl's behaviour.
1532 17. If a user had set PCREGREP_COLO(U)R to something other than 1:31, the
1533 RunGrepTest script failed.
1535 18. Change 22 for version 13 caused atomic groups to use more stack. This is
1536 inevitable for groups that contain captures, but it can lead to a lot of
1537 stack use in large patterns. The old behaviour has been restored for atomic
1538 groups that do not contain any capturing parentheses.
1540 19. If the PCRE_NO_START_OPTIMIZE option was set for pcre_compile(), it did not
1541 suppress the check for a minimum subject length at run time. (If it was
1542 given to pcre_exec() or pcre_dfa_exec() it did work.)
1544 20. Fixed an ASCII-dependent infelicity in pcretest that would have made it
1545 fail to work when decoding hex characters in data strings in EBCDIC
1546 environments.
1548 21. It appears that in at least one Mac OS environment, the isxdigit() function
1549 is implemented as a macro that evaluates to its argument more than once,
1550 contravening the C 90 Standard (I haven't checked a later standard). There
1551 was an instance in pcretest which caused it to go wrong when processing
1552 \x{...} escapes in subject strings. The has been rewritten to avoid using
1553 things like p++ in the argument of isxdigit().
1556 Version 8.13 16-Aug-2011
1557 ------------------------
1559 1. The Unicode data tables have been updated to Unicode 6.0.0.
1561 2. Two minor typos in pcre_internal.h have been fixed.
1563 3. Added #include <string.h> to pcre_scanner_unittest.cc, pcrecpp.cc, and
1564 pcrecpp_unittest.cc. They are needed for strcmp(), memset(), and strchr()
1565 in some environments (e.g. Solaris 10/SPARC using Sun Studio 12U2).
1567 4. There were a number of related bugs in the code for matching backrefences
1568 caselessly in UTF-8 mode when codes for the characters concerned were
1569 different numbers of bytes. For example, U+023A and U+2C65 are an upper
1570 and lower case pair, using 2 and 3 bytes, respectively. The main bugs were:
1571 (a) A reference to 3 copies of a 2-byte code matched only 2 of a 3-byte
1572 code. (b) A reference to 2 copies of a 3-byte code would not match 2 of a
1573 2-byte code at the end of the subject (it thought there wasn't enough data
1574 left).
1576 5. Comprehensive information about what went wrong is now returned by
1577 pcre_exec() and pcre_dfa_exec() when the UTF-8 string check fails, as long
1578 as the output vector has at least 2 elements. The offset of the start of
1579 the failing character and a reason code are placed in the vector.
1581 6. When the UTF-8 string check fails for pcre_compile(), the offset that is
1582 now returned is for the first byte of the failing character, instead of the
1583 last byte inspected. This is an incompatible change, but I hope it is small
1584 enough not to be a problem. It makes the returned offset consistent with
1585 pcre_exec() and pcre_dfa_exec().
1587 7. pcretest now gives a text phrase as well as the error number when
1588 pcre_exec() or pcre_dfa_exec() fails; if the error is a UTF-8 check
1589 failure, the offset and reason code are output.
1591 8. When \R was used with a maximizing quantifier it failed to skip backwards
1592 over a \r\n pair if the subsequent match failed. Instead, it just skipped
1593 back over a single character (\n). This seems wrong (because it treated the
1594 two characters as a single entity when going forwards), conflicts with the
1595 documentation that \R is equivalent to (?>\r\n|\n|...etc), and makes the
1596 behaviour of \R* different to (\R)*, which also seems wrong. The behaviour
1597 has been changed.
1599 9. Some internal refactoring has changed the processing so that the handling
1600 of the PCRE_CASELESS and PCRE_MULTILINE options is done entirely at compile
1601 time (the PCRE_DOTALL option was changed this way some time ago: version
1602 7.7 change 16). This has made it possible to abolish the OP_OPT op code,
1603 which was always a bit of a fudge. It also means that there is one less
1604 argument for the match() function, which reduces its stack requirements
1605 slightly. This change also fixes an incompatibility with Perl: the pattern
1606 (?i:([^b]))(?1) should not match "ab", but previously PCRE gave a match.
1608 10. More internal refactoring has drastically reduced the number of recursive
1609 calls to match() for possessively repeated groups such as (abc)++ when
1610 using pcre_exec().
1612 11. While implementing 10, a number of bugs in the handling of groups were
1613 discovered and fixed:
1615 (?<=(a)+) was not diagnosed as invalid (non-fixed-length lookbehind).
1616 (a|)*(?1) gave a compile-time internal error.
1617 ((a|)+)+ did not notice that the outer group could match an empty string.
1618 (^a|^)+ was not marked as anchored.
1619 (.*a|.*)+ was not marked as matching at start or after a newline.
1621 12. Yet more internal refactoring has removed another argument from the match()
1622 function. Special calls to this function are now indicated by setting a
1623 value in a variable in the "match data" data block.
1625 13. Be more explicit in pcre_study() instead of relying on "default" for
1626 opcodes that mean there is no starting character; this means that when new
1627 ones are added and accidentally left out of pcre_study(), testing should
1628 pick them up.
1630 14. The -s option of pcretest has been documented for ages as being an old
1631 synonym of -m (show memory usage). I have changed it to mean "force study
1632 for every regex", that is, assume /S for every regex. This is similar to -i
1633 and -d etc. It's slightly incompatible, but I'm hoping nobody is still
1634 using it. It makes it easier to run collections of tests with and without
1635 study enabled, and thereby test pcre_study() more easily. All the standard
1636 tests are now run with and without -s (but some patterns can be marked as
1637 "never study" - see 20 below).
1639 15. When (*ACCEPT) was used in a subpattern that was called recursively, the
1640 restoration of the capturing data to the outer values was not happening
1641 correctly.
1643 16. If a recursively called subpattern ended with (*ACCEPT) and matched an
1644 empty string, and PCRE_NOTEMPTY was set, pcre_exec() thought the whole
1645 pattern had matched an empty string, and so incorrectly returned a no
1646 match.
1648 17. There was optimizing code for the last branch of non-capturing parentheses,
1649 and also for the obeyed branch of a conditional subexpression, which used
1650 tail recursion to cut down on stack usage. Unfortunately, now that there is
1651 the possibility of (*THEN) occurring in these branches, tail recursion is
1652 no longer possible because the return has to be checked for (*THEN). These
1653 two optimizations have therefore been removed. [But see 8.20/11 above.]
1655 18. If a pattern containing \R was studied, it was assumed that \R always
1656 matched two bytes, thus causing the minimum subject length to be
1657 incorrectly computed because \R can also match just one byte.
1659 19. If a pattern containing (*ACCEPT) was studied, the minimum subject length
1660 was incorrectly computed.
1662 20. If /S is present twice on a test pattern in pcretest input, it now
1663 *disables* studying, thereby overriding the use of -s on the command line
1664 (see 14 above). This is necessary for one or two tests to keep the output
1665 identical in both cases.
1667 21. When (*ACCEPT) was used in an assertion that matched an empty string and
1668 PCRE_NOTEMPTY was set, PCRE applied the non-empty test to the assertion.
1670 22. When an atomic group that contained a capturing parenthesis was
1671 successfully matched, but the branch in which it appeared failed, the
1672 capturing was not being forgotten if a higher numbered group was later
1673 captured. For example, /(?>(a))b|(a)c/ when matching "ac" set capturing
1674 group 1 to "a", when in fact it should be unset. This applied to multi-
1675 branched capturing and non-capturing groups, repeated or not, and also to
1676 positive assertions (capturing in negative assertions does not happen
1677 in PCRE) and also to nested atomic groups.
1679 23. Add the ++ qualifier feature to pcretest, to show the remainder of the
1680 subject after a captured substring, to make it easier to tell which of a
1681 number of identical substrings has been captured.
1683 24. The way atomic groups are processed by pcre_exec() has been changed so that
1684 if they are repeated, backtracking one repetition now resets captured
1685 values correctly. For example, if ((?>(a+)b)+aabab) is matched against
1686 "aaaabaaabaabab" the value of captured group 2 is now correctly recorded as
1687 "aaa". Previously, it would have been "a". As part of this code
1688 refactoring, the way recursive calls are handled has also been changed.
1690 25. If an assertion condition captured any substrings, they were not passed
1691 back unless some other capturing happened later. For example, if
1692 (?(?=(a))a) was matched against "a", no capturing was returned.
1694 26. When studying a pattern that contained subroutine calls or assertions,
1695 the code for finding the minimum length of a possible match was handling
1696 direct recursions such as (xxx(?1)|yyy) but not mutual recursions (where
1697 group 1 called group 2 while simultaneously a separate group 2 called group
1698 1). A stack overflow occurred in this case. I have fixed this by limiting
1699 the recursion depth to 10.
1701 27. Updated RunTest.bat in the distribution to the version supplied by Tom
1702 Fortmann. This supports explicit test numbers on the command line, and has
1703 argument validation and error reporting.
1705 28. An instance of \X with an unlimited repeat could fail if at any point the
1706 first character it looked at was a mark character.
1708 29. Some minor code refactoring concerning Unicode properties and scripts
1709 should reduce the stack requirement of match() slightly.
1711 30. Added the '=' option to pcretest to check the setting of unused capturing
1712 slots at the end of the pattern, which are documented as being -1, but are
1713 not included in the return count.
1715 31. If \k was not followed by a braced, angle-bracketed, or quoted name, PCRE
1716 compiled something random. Now it gives a compile-time error (as does
1717 Perl).
1719 32. A *MARK encountered during the processing of a positive assertion is now
1720 recorded and passed back (compatible with Perl).
1722 33. If --only-matching or --colour was set on a pcregrep call whose pattern
1723 had alternative anchored branches, the search for a second match in a line
1724 was done as if at the line start. Thus, for example, /^01|^02/ incorrectly
1725 matched the line "0102" twice. The same bug affected patterns that started
1726 with a backwards assertion. For example /\b01|\b02/ also matched "0102"
1727 twice.
1729 34. Previously, PCRE did not allow quantification of assertions. However, Perl
1730 does, and because of capturing effects, quantifying parenthesized
1731 assertions may at times be useful. Quantifiers are now allowed for
1732 parenthesized assertions.
1734 35. A minor code tidy in pcre_compile() when checking options for \R usage.
1736 36. \g was being checked for fancy things in a character class, when it should
1737 just be a literal "g".
1739 37. PCRE was rejecting [:a[:digit:]] whereas Perl was not. It seems that the
1740 appearance of a nested POSIX class supersedes an apparent external class.
1741 For example, [:a[:digit:]b:] matches "a", "b", ":", or a digit. Also,
1742 unescaped square brackets may also appear as part of class names. For
1743 example, [:a[:abc]b:] gives unknown class "[:abc]b:]". PCRE now behaves
1744 more like Perl. (But see 8.20/1 above.)
1746 38. PCRE was giving an error for \N with a braced quantifier such as {1,} (this
1747 was because it thought it was \N{name}, which is not supported).
1749 39. Add minix to OS list not supporting the -S option in pcretest.
1751 40. PCRE tries to detect cases of infinite recursion at compile time, but it
1752 cannot analyze patterns in sufficient detail to catch mutual recursions
1753 such as ((?1))((?2)). There is now a runtime test that gives an error if a
1754 subgroup is called recursively as a subpattern for a second time at the
1755 same position in the subject string. In previous releases this might have
1756 been caught by the recursion limit, or it might have run out of stack.
1758 41. A pattern such as /(?(R)a+|(?R)b)/ is quite safe, as the recursion can
1759 happen only once. PCRE was, however incorrectly giving a compile time error
1760 "recursive call could loop indefinitely" because it cannot analyze the
1761 pattern in sufficient detail. The compile time test no longer happens when
1762 PCRE is compiling a conditional subpattern, but actual runaway loops are
1763 now caught at runtime (see 40 above).
1765 42. It seems that Perl allows any characters other than a closing parenthesis
1766 to be part of the NAME in (*MARK:NAME) and other backtracking verbs. PCRE
1767 has been changed to be the same.
1769 43. Updated configure.ac to put in more quoting round AC_LANG_PROGRAM etc. so
1770 as not to get warnings when autogen.sh is called. Also changed
1771 AC_PROG_LIBTOOL (deprecated) to LT_INIT (the current macro).
1773 44. To help people who use pcregrep to scan files containing exceedingly long
1774 lines, the following changes have been made:
1776 (a) The default value of the buffer size parameter has been increased from
1777 8K to 20K. (The actual buffer used is three times this size.)
1779 (b) The default can be changed by ./configure --with-pcregrep-bufsize when
1780 PCRE is built.
1782 (c) A --buffer-size=n option has been added to pcregrep, to allow the size
1783 to be set at run time.
1785 (d) Numerical values in pcregrep options can be followed by K or M, for
1786 example --buffer-size=50K.
1788 (e) If a line being scanned overflows pcregrep's buffer, an error is now
1789 given and the return code is set to 2.
1791 45. Add a pointer to the latest mark to the callout data block.
1793 46. The pattern /.(*F)/, when applied to "abc" with PCRE_PARTIAL_HARD, gave a
1794 partial match of an empty string instead of no match. This was specific to
1795 the use of ".".
1797 47. The pattern /f.*/8s, when applied to "for" with PCRE_PARTIAL_HARD, gave a
1798 complete match instead of a partial match. This bug was dependent on both
1799 the PCRE_UTF8 and PCRE_DOTALL options being set.
1801 48. For a pattern such as /\babc|\bdef/ pcre_study() was failing to set up the
1802 starting byte set, because \b was not being ignored.
1805 Version 8.12 15-Jan-2011
1806 ------------------------
1808 1. Fixed some typos in the markup of the man pages, and wrote a script that
1809 checks for such things as part of the documentation building process.
1811 2. On a big-endian 64-bit system, pcregrep did not correctly process the
1812 --match-limit and --recursion-limit options (added for 8.11). In
1813 particular, this made one of the standard tests fail. (The integer value
1814 went into the wrong half of a long int.)
1816 3. If the --colour option was given to pcregrep with -v (invert match), it
1817 did strange things, either producing crazy output, or crashing. It should,
1818 of course, ignore a request for colour when reporting lines that do not
1819 match.
1821 4. Another pcregrep bug caused similar problems if --colour was specified with
1822 -M (multiline) and the pattern match finished with a line ending.
1824 5. In pcregrep, when a pattern that ended with a literal newline sequence was
1825 matched in multiline mode, the following line was shown as part of the
1826 match. This seems wrong, so I have changed it.
1828 6. Another pcregrep bug in multiline mode, when --colour was specified, caused
1829 the check for further matches in the same line (so they could be coloured)
1830 to overrun the end of the current line. If another match was found, it was
1831 incorrectly shown (and then shown again when found in the next line).
1833 7. If pcregrep was compiled under Windows, there was a reference to the
1834 function pcregrep_exit() before it was defined. I am assuming this was
1835 the cause of the "error C2371: 'pcregrep_exit' : redefinition;" that was
1836 reported by a user. I've moved the definition above the reference.
1839 Version 8.11 10-Dec-2010
1840 ------------------------
1842 1. (*THEN) was not working properly if there were untried alternatives prior
1843 to it in the current branch. For example, in ((a|b)(*THEN)(*F)|c..) it
1844 backtracked to try for "b" instead of moving to the next alternative branch
1845 at the same level (in this case, to look for "c"). The Perl documentation
1846 is clear that when (*THEN) is backtracked onto, it goes to the "next
1847 alternative in the innermost enclosing group".
1849 2. (*COMMIT) was not overriding (*THEN), as it does in Perl. In a pattern
1850 such as (A(*COMMIT)B(*THEN)C|D) any failure after matching A should
1851 result in overall failure. Similarly, (*COMMIT) now overrides (*PRUNE) and
1852 (*SKIP), (*SKIP) overrides (*PRUNE) and (*THEN), and (*PRUNE) overrides
1853 (*THEN).
1855 3. If \s appeared in a character class, it removed the VT character from
1856 the class, even if it had been included by some previous item, for example
1857 in [\x00-\xff\s]. (This was a bug related to the fact that VT is not part
1858 of \s, but is part of the POSIX "space" class.)
1860 4. A partial match never returns an empty string (because you can always
1861 match an empty string at the end of the subject); however the checking for
1862 an empty string was starting at the "start of match" point. This has been
1863 changed to the "earliest inspected character" point, because the returned
1864 data for a partial match starts at this character. This means that, for
1865 example, /(?<=abc)def/ gives a partial match for the subject "abc"
1866 (previously it gave "no match").
1868 5. Changes have been made to the way PCRE_PARTIAL_HARD affects the matching
1869 of $, \z, \Z, \b, and \B. If the match point is at the end of the string,
1870 previously a full match would be given. However, setting PCRE_PARTIAL_HARD
1871 has an implication that the given string is incomplete (because a partial
1872 match is preferred over a full match). For this reason, these items now
1873 give a partial match in this situation. [Aside: previously, the one case
1874 /t\b/ matched against "cat" with PCRE_PARTIAL_HARD set did return a partial
1875 match rather than a full match, which was wrong by the old rules, but is
1876 now correct.]
1878 6. There was a bug in the handling of #-introduced comments, recognized when
1879 PCRE_EXTENDED is set, when PCRE_NEWLINE_ANY and PCRE_UTF8 were also set.
1880 If a UTF-8 multi-byte character included the byte 0x85 (e.g. +U0445, whose
1881 UTF-8 encoding is 0xd1,0x85), this was misinterpreted as a newline when
1882 scanning for the end of the comment. (*Character* 0x85 is an "any" newline,
1883 but *byte* 0x85 is not, in UTF-8 mode). This bug was present in several
1884 places in pcre_compile().
1886 7. Related to (6) above, when pcre_compile() was skipping #-introduced
1887 comments when looking ahead for named forward references to subpatterns,
1888 the only newline sequence it recognized was NL. It now handles newlines
1889 according to the set newline convention.
1891 8. SunOS4 doesn't have strerror() or strtoul(); pcregrep dealt with the
1892 former, but used strtoul(), whereas pcretest avoided strtoul() but did not
1893 cater for a lack of strerror(). These oversights have been fixed.
1895 9. Added --match-limit and --recursion-limit to pcregrep.
1897 10. Added two casts needed to build with Visual Studio when NO_RECURSE is set.
1899 11. When the -o option was used, pcregrep was setting a return code of 1, even
1900 when matches were found, and --line-buffered was not being honoured.
1902 12. Added an optional parentheses number to the -o and --only-matching options
1903 of pcregrep.
1905 13. Imitating Perl's /g action for multiple matches is tricky when the pattern
1906 can match an empty string. The code to do it in pcretest and pcredemo
1907 needed fixing:
1909 (a) When the newline convention was "crlf", pcretest got it wrong, skipping
1910 only one byte after an empty string match just before CRLF (this case
1911 just got forgotten; "any" and "anycrlf" were OK).
1913 (b) The pcretest code also had a bug, causing it to loop forever in UTF-8
1914 mode when an empty string match preceded an ASCII character followed by
1915 a non-ASCII character. (The code for advancing by one character rather
1916 than one byte was nonsense.)
1918 (c) The pcredemo.c sample program did not have any code at all to handle
1919 the cases when CRLF is a valid newline sequence.
1921 14. Neither pcre_exec() nor pcre_dfa_exec() was checking that the value given
1922 as a starting offset was within the subject string. There is now a new
1923 error, PCRE_ERROR_BADOFFSET, which is returned if the starting offset is
1924 negative or greater than the length of the string. In order to test this,
1925 pcretest is extended to allow the setting of negative starting offsets.
1927 15. In both pcre_exec() and pcre_dfa_exec() the code for checking that the
1928 starting offset points to the beginning of a UTF-8 character was
1929 unnecessarily clumsy. I tidied it up.
1931 16. Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
1932 bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
1934 17. Nobody had reported that the --include_dir option, which was added in
1935 release 7.7 should have been called --include-dir (hyphen, not underscore)
1936 for compatibility with GNU grep. I have changed it to --include-dir, but
1937 left --include_dir as an undocumented synonym, and the same for
1938 --exclude-dir, though that is not available in GNU grep, at least as of
1939 release 2.5.4.
1941 18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
1942 characters from a string of bytes) have been redefined so as not to use
1943 loops, in order to improve performance in some environments. At the same
1944 time, I abstracted some of the common code into auxiliary macros to save
1945 repetition (this should not affect the compiled code).
1947 19. If \c was followed by a multibyte UTF-8 character, bad things happened. A
1948 compile-time error is now given if \c is not followed by an ASCII
1949 character, that is, a byte less than 128. (In EBCDIC mode, the code is
1950 different, and any byte value is allowed.)
1952 20. Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
1953 START_OPTIMIZE option, which is now allowed at compile time - but just
1954 passed through to pcre_exec() or pcre_dfa_exec(). This makes it available
1955 to pcregrep and other applications that have no direct access to PCRE
1956 options. The new /Y option in pcretest sets this option when calling
1957 pcre_compile().
1959 21. Change 18 of release 8.01 broke the use of named subpatterns for recursive
1960 back references. Groups containing recursive back references were forced to
1961 be atomic by that change, but in the case of named groups, the amount of
1962 memory required was incorrectly computed, leading to "Failed: internal
1963 error: code overflow". This has been fixed.
1965 22. Some patches to pcre_stringpiece.h, pcre_stringpiece_unittest.cc, and
1966 pcretest.c, to avoid build problems in some Borland environments.
1969 Version 8.10 25-Jun-2010
1970 ------------------------
1972 1. Added support for (*MARK:ARG) and for ARG additions to PRUNE, SKIP, and
1973 THEN.
1975 2. (*ACCEPT) was not working when inside an atomic group.
1977 3. Inside a character class, \B is treated as a literal by default, but
1978 faulted if PCRE_EXTRA is set. This mimics Perl's behaviour (the -w option
1979 causes the error). The code is unchanged, but I tidied the documentation.
1981 4. Inside a character class, PCRE always treated \R and \X as literals,
1982 whereas Perl faults them if its -w option is set. I have changed PCRE so
1983 that it faults them when PCRE_EXTRA is set.
1985 5. Added support for \N, which always matches any character other than
1986 newline. (It is the same as "." when PCRE_DOTALL is not set.)
1988 6. When compiling pcregrep with newer versions of gcc which may have
1989 FORTIFY_SOURCE set, several warnings "ignoring return value of 'fwrite',
1990 declared with attribute warn_unused_result" were given. Just casting the
1991 result to (void) does not stop the warnings; a more elaborate fudge is
1992 needed. I've used a macro to implement this.
1994 7. Minor change to pcretest.c to avoid a compiler warning.
1996 8. Added four artifical Unicode properties to help with an option to make
1997 \s etc use properties (see next item). The new properties are: Xan
1998 (alphanumeric), Xsp (Perl space), Xps (POSIX space), and Xwd (word).
2000 9. Added PCRE_UCP to make \b, \d, \s, \w, and certain POSIX character classes
2001 use Unicode properties. (*UCP) at the start of a pattern can be used to set
2002 this option. Modified pcretest to add /W to test this facility. Added
2003 REG_UCP to make it available via the POSIX interface.
2005 10. Added --line-buffered to pcregrep.
2007 11. In UTF-8 mode, if a pattern that was compiled with PCRE_CASELESS was
2008 studied, and the match started with a letter with a code point greater than
2009 127 whose first byte was different to the first byte of the other case of
2010 the letter, the other case of this starting letter was not recognized
2011 (#976).
2013 12. If a pattern that was studied started with a repeated Unicode property
2014 test, for example, \p{Nd}+, there was the theoretical possibility of
2015 setting up an incorrect bitmap of starting bytes, but fortunately it could
2016 not have actually happened in practice until change 8 above was made (it
2017 added property types that matched character-matching opcodes).
2019 13. pcre_study() now recognizes \h, \v, and \R when constructing a bit map of
2020 possible starting bytes for non-anchored patterns.
2022 14. Extended the "auto-possessify" feature of pcre_compile(). It now recognizes
2023 \R, and also a number of cases that involve Unicode properties, both
2024 explicit and implicit when PCRE_UCP is set.
2026 15. If a repeated Unicode property match (e.g. \p{Lu}*) was used with non-UTF-8
2027 input, it could crash or give wrong results if characters with values
2028 greater than 0xc0 were present in the subject string. (Detail: it assumed
2029 UTF-8 input when processing these items.)
2031 16. Added a lot of (int) casts to avoid compiler warnings in systems where
2032 size_t is 64-bit (#991).
2034 17. Added a check for running out of memory when PCRE is compiled with
2035 --disable-stack-for-recursion (#990).
2037 18. If the last data line in a file for pcretest does not have a newline on
2038 the end, a newline was missing in the output.
2040 19. The default pcre_chartables.c file recognizes only ASCII characters (values
2041 less than 128) in its various bitmaps. However, there is a facility for
2042 generating tables according to the current locale when PCRE is compiled. It
2043 turns out that in some environments, 0x85 and 0xa0, which are Unicode space
2044 characters, are recognized by isspace() and therefore were getting set in
2045 these tables, and indeed these tables seem to approximate to ISO 8859. This
2046 caused a problem in UTF-8 mode when pcre_study() was used to create a list
2047 of bytes that can start a match. For \s, it was including 0x85 and 0xa0,
2048 which of course cannot start UTF-8 characters. I have changed the code so
2049 that only real ASCII characters (less than 128) and the correct starting
2050 bytes for UTF-8 encodings are set for characters greater than 127 when in
2051 UTF-8 mode. (When PCRE_UCP is set - see 9 above - the code is different
2052 altogether.)
2054 20. Added the /T option to pcretest so as to be able to run tests with non-
2055 standard character tables, thus making it possible to include the tests
2056 used for 19 above in the standard set of tests.
2058 21. A pattern such as (?&t)(?#()(?(DEFINE)(?<t>a)) which has a forward
2059 reference to a subpattern the other side of a comment that contains an
2060 opening parenthesis caused either an internal compiling error, or a
2061 reference to the wrong subpattern.
2064 Version 8.02 19-Mar-2010
2065 ------------------------
2067 1. The Unicode data tables have been updated to Unicode 5.2.0.
2069 2. Added the option --libs-cpp to pcre-config, but only when C++ support is
2070 configured.
2072 3. Updated the licensing terms in the pcregexp.pas file, as agreed with the
2073 original author of that file, following a query about its status.
2075 4. On systems that do not have stdint.h (e.g. Solaris), check for and include
2076 inttypes.h instead. This fixes a bug that was introduced by change 8.01/8.
2078 5. A pattern such as (?&t)*+(?(DEFINE)(?<t>.)) which has a possessive
2079 quantifier applied to a forward-referencing subroutine call, could compile
2080 incorrect code or give the error "internal error: previously-checked
2081 referenced subpattern not found".
2083 6. Both MS Visual Studio and Symbian OS have problems with initializing
2084 variables to point to external functions. For these systems, therefore,
2085 pcre_malloc etc. are now initialized to local functions that call the
2086 relevant global functions.
2088 7. There were two entries missing in the vectors called coptable and poptable
2089 in pcre_dfa_exec.c. This could lead to memory accesses outsize the vectors.
2090 I've fixed the data, and added a kludgy way of testing at compile time that
2091 the lengths are correct (equal to the number of opcodes).
2093 8. Following on from 7, I added a similar kludge to check the length of the
2094 eint vector in pcreposix.c.
2096 9. Error texts for pcre_compile() are held as one long string to avoid too
2097 much relocation at load time. To find a text, the string is searched,
2098 counting zeros. There was no check for running off the end of the string,
2099 which could happen if a new error number was added without updating the
2100 string.
2102 10. \K gave a compile-time error if it appeared in a lookbehind assersion.
2104 11. \K was not working if it appeared in an atomic group or in a group that
2105 was called as a "subroutine", or in an assertion. Perl 5.11 documents that
2106 \K is "not well defined" if used in an assertion. PCRE now accepts it if
2107 the assertion is positive, but not if it is negative.
2109 12. Change 11 fortuitously reduced the size of the stack frame used in the
2110 "match()" function of pcre_exec.c by one pointer. Forthcoming
2111 implementation of support for (*MARK) will need an extra pointer on the
2112 stack; I have reserved it now, so that the stack frame size does not
2113 decrease.
2115 13. A pattern such as (?P<L1>(?P<L2>0)|(?P>L2)(?P>L1)) in which the only other
2116 item in branch that calls a recursion is a subroutine call - as in the
2117 second branch in the above example - was incorrectly given the compile-
2118 time error "recursive call could loop indefinitely" because pcre_compile()
2119 was not correctly checking the subroutine for matching a non-empty string.
2121 14. The checks for overrunning compiling workspace could trigger after an
2122 overrun had occurred. This is a "should never occur" error, but it can be
2123 triggered by pathological patterns such as hundreds of nested parentheses.
2124 The checks now trigger 100 bytes before the end of the workspace.
2126 15. Fix typo in configure.ac: "srtoq" should be "strtoq".
2129 Version 8.01 19-Jan-2010
2130 ------------------------
2132 1. If a pattern contained a conditional subpattern with only one branch (in
2133 particular, this includes all (*DEFINE) patterns), a call to pcre_study()
2134 computed the wrong minimum data length (which is of course zero for such
2135 subpatterns). This could cause incorrect "no match" results.
2137 2. For patterns such as (?i)a(?-i)b|c where an option setting at the start of
2138 the pattern is reset in the first branch, pcre_compile() failed with
2139 "internal error: code overflow at offset...". This happened only when
2140 the reset was to the original external option setting. (An optimization
2141 abstracts leading options settings into an external setting, which was the
2142 cause of this.)
2144 3. A pattern such as ^(?!a(*SKIP)b) where a negative assertion contained one
2145 of the verbs SKIP, PRUNE, or COMMIT, did not work correctly. When the
2146 assertion pattern did not match (meaning that the assertion was true), it
2147 was incorrectly treated as false if the SKIP had been reached during the
2148 matching. This also applied to assertions used as conditions.
2150 4. If an item that is not supported by pcre_dfa_exec() was encountered in an
2151 assertion subpattern, including such a pattern used as a condition,
2152 unpredictable results occurred, instead of the error return
2155 5. The C++ GlobalReplace function was not working like Perl for the special
2156 situation when an empty string is matched. It now does the fancy magic
2157 stuff that is necessary.
2159 6. In pcre_internal.h, obsolete includes to setjmp.h and stdarg.h have been
2160 removed. (These were left over from very, very early versions of PCRE.)
2162 7. Some cosmetic changes to the code to make life easier when compiling it
2163 as part of something else:
2165 (a) Change DEBUG to PCRE_DEBUG.
2167 (b) In pcre_compile(), rename the member of the "branch_chain" structure
2168 called "current" as "current_branch", to prevent a collision with the
2169 Linux macro when compiled as a kernel module.
2171 (c) In pcre_study(), rename the function set_bit() as set_table_bit(), to
2172 prevent a collision with the Linux macro when compiled as a kernel
2173 module.
2175 8. In pcre_compile() there are some checks for integer overflows that used to
2176 cast potentially large values to (double). This has been changed to that
2177 when building, a check for int64_t is made, and if it is found, it is used
2178 instead, thus avoiding the use of floating point arithmetic. (There is no
2179 other use of FP in PCRE.) If int64_t is not found, the fallback is to
2180 double.
2182 9. Added two casts to avoid signed/unsigned warnings from VS Studio Express
2183 2005 (difference between two addresses compared to an unsigned value).
2185 10. Change the standard AC_CHECK_LIB test for libbz2 in configure.ac to a
2186 custom one, because of the following reported problem in Windows:
2188 - libbz2 uses the Pascal calling convention (WINAPI) for the functions
2189 under Win32.
2190 - The standard autoconf AC_CHECK_LIB fails to include "bzlib.h",
2191 therefore missing the function definition.
2192 - The compiler thus generates a "C" signature for the test function.
2193 - The linker fails to find the "C" function.
2194 - PCRE fails to configure if asked to do so against libbz2.
2196 11. When running libtoolize from libtool-2.2.6b as part of autogen.sh, these
2197 messages were output:
2199 Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
2200 rerunning libtoolize, to keep the correct libtool macros in-tree.
2201 Consider adding `-I m4' to ACLOCAL_AMFLAGS in Makefile.am.
2203 I have done both of these things.
2205 12. Although pcre_dfa_exec() does not use nearly as much stack as pcre_exec()
2206 most of the time, it *can* run out if it is given a pattern that contains a
2207 runaway infinite recursion. I updated the discussion in the pcrestack man
2208 page.
2210 13. Now that we have gone to the x.xx style of version numbers, the minor
2211 version may start with zero. Using 08 or 09 is a bad idea because users
2212 might check the value of PCRE_MINOR in their code, and 08 or 09 may be
2213 interpreted as invalid octal numbers. I've updated the previous comment in
2214 configure.ac, and also added a check that gives an error if 08 or 09 are
2215 used.
2217 14. Change 8.00/11 was not quite complete: code had been accidentally omitted,
2218 causing partial matching to fail when the end of the subject matched \W
2219 in a UTF-8 pattern where \W was quantified with a minimum of 3.
2221 15. There were some discrepancies between the declarations in pcre_internal.h
2222 of _pcre_is_newline(), _pcre_was_newline(), and _pcre_valid_utf8() and
2223 their definitions. The declarations used "const uschar *" and the
2224 definitions used USPTR. Even though USPTR is normally defined as "const
2225 unsigned char *" (and uschar is typedeffed as "unsigned char"), it was
2226 reported that: "This difference in casting confuses some C++ compilers, for
2227 example, SunCC recognizes above declarations as different functions and
2228 generates broken code for hbpcre." I have changed the declarations to use
2229 USPTR.
2231 16. GNU libtool is named differently on some systems. The autogen.sh script now
2232 tries several variants such as glibtoolize (MacOSX) and libtoolize1x
2233 (FreeBSD).
2235 17. Applied Craig's patch that fixes an HP aCC compile error in pcre 8.00
2236 (strtoXX undefined when compiling pcrecpp.cc). The patch contains this
2237 comment: "Figure out how to create a longlong from a string: strtoll and
2238 equivalent. It's not enough to call AC_CHECK_FUNCS: hpux has a strtoll, for
2239 instance, but it only takes 2 args instead of 3!"
2241 18. A subtle bug concerned with back references has been fixed by a change of
2242 specification, with a corresponding code fix. A pattern such as
2243 ^(xa|=?\1a)+$ which contains a back reference inside the group to which it
2244 refers, was giving matches when it shouldn't. For example, xa=xaaa would
2245 match that pattern. Interestingly, Perl (at least up to 5.11.3) has the
2246 same bug. Such groups have to be quantified to be useful, or contained
2247 inside another quantified group. (If there's no repetition, the reference
2248 can never match.) The problem arises because, having left the group and
2249 moved on to the rest of the pattern, a later failure that backtracks into
2250 the group uses the captured value from the final iteration of the group
2251 rather than the correct earlier one. I have fixed this in PCRE by forcing
2252 any group that contains a reference to itself to be an atomic group; that
2253 is, there cannot be any backtracking into it once it has completed. This is
2254 similar to recursive and subroutine calls.
2257 Version 8.00 19-Oct-09
2258 ----------------------
2260 1. The table for translating pcre_compile() error codes into POSIX error codes
2261 was out-of-date, and there was no check on the pcre_compile() error code
2262 being within the table. This could lead to an OK return being given in
2263 error.
2265 2. Changed the call to open a subject file in pcregrep from fopen(pathname,
2266 "r") to fopen(pathname, "rb"), which fixed a problem with some of the tests
2267 in a Windows environment.
2269 3. The pcregrep --count option prints the count for each file even when it is
2270 zero, as does GNU grep. However, pcregrep was also printing all files when
2271 --files-with-matches was added. Now, when both options are given, it prints
2272 counts only for those files that have at least one match. (GNU grep just
2273 prints the file name in this circumstance, but including the count seems
2274 more useful - otherwise, why use --count?) Also ensured that the
2275 combination -clh just lists non-zero counts, with no names.
2277 4. The long form of the pcregrep -F option was incorrectly implemented as
2278 --fixed_strings instead of --fixed-strings. This is an incompatible change,
2279 but it seems right to fix it, and I didn't think it was worth preserving
2280 the old behaviour.
2282 5. The command line items --regex=pattern and --regexp=pattern were not
2283 recognized by pcregrep, which required --regex pattern or --regexp pattern
2284 (with a space rather than an '='). The man page documented the '=' forms,
2285 which are compatible with GNU grep; these now work.
2287 6. No libpcreposix.pc file was created for pkg-config; there was just
2288 libpcre.pc and libpcrecpp.pc. The omission has been rectified.
2290 7. Added #ifndef SUPPORT_UCP into the pcre_ucd.c module, to reduce its size
2291 when UCP support is not needed, by modifying the Python script that
2292 generates it from Unicode data files. This should not matter if the module
2293 is correctly used as a library, but I received one complaint about 50K of
2294 unwanted data. My guess is that the person linked everything into his
2295 program rather than using a library. Anyway, it does no harm.
2297 8. A pattern such as /\x{123}{2,2}+/8 was incorrectly compiled; the trigger
2298 was a minimum greater than 1 for a wide character in a possessive
2299 repetition. The same bug could also affect patterns like /(\x{ff}{0,2})*/8
2300 which had an unlimited repeat of a nested, fixed maximum repeat of a wide
2301 character. Chaos in the form of incorrect output or a compiling loop could
2302 result.
2304 9. The restrictions on what a pattern can contain when partial matching is
2305 requested for pcre_exec() have been removed. All patterns can now be
2306 partially matched by this function. In addition, if there are at least two
2307 slots in the offset vector, the offset of the earliest inspected character
2308 for the match and the offset of the end of the subject are set in them when
2309 PCRE_ERROR_PARTIAL is returned.
2311 10. Partial matching has been split into two forms: PCRE_PARTIAL_SOFT, which is
2312 synonymous with PCRE_PARTIAL, for backwards compatibility, and
2313 PCRE_PARTIAL_HARD, which causes a partial match to supersede a full match,
2314 and may be more useful for multi-segment matching.
2316 11. Partial matching with pcre_exec() is now more intuitive. A partial match
2317 used to be given if ever the end of the subject was reached; now it is
2318 given only if matching could not proceed because another character was
2319 needed. This makes a difference in some odd cases such as Z(*FAIL) with the
2320 string "Z", which now yields "no match" instead of "partial match". In the
2321 case of pcre_dfa_exec(), "no match" is given if every matching path for the
2322 final character ended with (*FAIL).
2324 12. Restarting a match using pcre_dfa_exec() after a partial match did not work
2325 if the pattern had a "must contain" character that was already found in the
2326 earlier partial match, unless partial matching was again requested. For
2327 example, with the pattern /dog.(body)?/, the "must contain" character is
2328 "g". If the first part-match was for the string "dog", restarting with
2329 "sbody" failed. This bug has been fixed.
2331 13. The string returned by pcre_dfa_exec() after a partial match has been
2332 changed so that it starts at the first inspected character rather than the
2333 first character of the match. This makes a difference only if the pattern
2334 starts with a lookbehind assertion or \b or \B (\K is not supported by
2335 pcre_dfa_exec()). It's an incompatible change, but it makes the two
2336 matching functions compatible, and I think it's the right thing to do.
2338 14. Added a pcredemo man page, created automatically from the pcredemo.c file,
2339 so that the demonstration program is easily available in environments where
2340 PCRE has not been installed from source.
2342 15. Arranged to add -DPCRE_STATIC to cflags in libpcre.pc, libpcreposix.cp,
2343 libpcrecpp.pc and pcre-config when PCRE is not compiled as a shared
2344 library.
2346 16. Added REG_UNGREEDY to the pcreposix interface, at the request of a user.
2347 It maps to PCRE_UNGREEDY. It is not, of course, POSIX-compatible, but it
2348 is not the first non-POSIX option to be added. Clearly some people find
2349 these options useful.
2351 17. If a caller to the POSIX matching function regexec() passes a non-zero
2352 value for nmatch with a NULL value for pmatch, the value of
2353 nmatch is forced to zero.
2355 18. RunGrepTest did not have a test for the availability of the -u option of
2356 the diff command, as RunTest does. It now checks in the same way as
2357 RunTest, and also checks for the -b option.
2359 19. If an odd number of negated classes containing just a single character
2360 interposed, within parentheses, between a forward reference to a named
2361 subpattern and the definition of the subpattern, compilation crashed with
2362 an internal error, complaining that it could not find the referenced
2363 subpattern. An example of a crashing pattern is /(?&A)(([^m])(?<A>))/.
2364 [The bug was that it was starting one character too far in when skipping
2365 over the character class, thus treating the ] as data rather than
2366 terminating the class. This meant it could skip too much.]
2368 20. Added PCRE_NOTEMPTY_ATSTART in order to be able to correctly implement the
2369 /g option in pcretest when the pattern contains \K, which makes it possible
2370 to have an empty string match not at the start, even when the pattern is
2371 anchored. Updated pcretest and pcredemo to use this option.
2373 21. If the maximum number of capturing subpatterns in a recursion was greater
2374 than the maximum at the outer level, the higher number was returned, but
2375 with unset values at the outer level. The correct (outer level) value is
2376 now given.
2378 22. If (*ACCEPT) appeared inside capturing parentheses, previous releases of
2379 PCRE did not set those parentheses (unlike Perl). I have now found a way to
2380 make it do so. The string so far is captured, making this feature
2381 compatible with Perl.
2383 23. The tests have been re-organized, adding tests 11 and 12, to make it
2384 possible to check the Perl 5.10 features against Perl 5.10.
2386 24. Perl 5.10 allows subroutine calls in lookbehinds, as long as the subroutine
2387 pattern matches a fixed length string. PCRE did not allow this; now it
2388 does. Neither allows recursion.
2390 25. I finally figured out how to implement a request to provide the minimum
2391 length of subject string that was needed in order to match a given pattern.
2392 (It was back references and recursion that I had previously got hung up
2393 on.) This code has now been added to pcre_study(); it finds a lower bound
2394 to the length of subject needed. It is not necessarily the greatest lower
2395 bound, but using it to avoid searching strings that are too short does give
2396 some useful speed-ups. The value is available to calling programs via
2397 pcre_fullinfo().
2399 26. While implementing 25, I discovered to my embarrassment that pcretest had
2400 not been passing the result of pcre_study() to pcre_dfa_exec(), so the
2401 study optimizations had never been tested with that matching function.
2402 Oops. What is worse, even when it was passed study data, there was a bug in
2403 pcre_dfa_exec() that meant it never actually used it. Double oops. There
2404 were also very few tests of studied patterns with pcre_dfa_exec().
2406 27. If (?| is used to create subpatterns with duplicate numbers, they are now
2407 allowed to have the same name, even if PCRE_DUPNAMES is not set. However,
2408 on the other side of the coin, they are no longer allowed to have different
2409 names, because these cannot be distinguished in PCRE, and this has caused
2410 confusion. (This is a difference from Perl.)
2412 28. When duplicate subpattern names are present (necessarily with different
2413 numbers, as required by 27 above), and a test is made by name in a
2414 conditional pattern, either for a subpattern having been matched, or for
2415 recursion in such a pattern, all the associated numbered subpatterns are
2416 tested, and the overall condition is true if the condition is true for any
2417 one of them. This is the way Perl works, and is also more like the way
2418 testing by number works.
2421 Version 7.9 11-Apr-09
2422 ---------------------
2424 1. When building with support for bzlib/zlib (pcregrep) and/or readline
2425 (pcretest), all targets were linked against these libraries. This included
2426 libpcre, libpcreposix, and libpcrecpp, even though they do not use these
2427 libraries. This caused unwanted dependencies to be created. This problem
2428 has been fixed, and now only pcregrep is linked with bzlib/zlib and only
2429 pcretest is linked with readline.
2431 2. The "typedef int BOOL" in pcre_internal.h that was included inside the
2432 "#ifndef FALSE" condition by an earlier change (probably 7.8/18) has been
2433 moved outside it again, because FALSE and TRUE are already defined in AIX,
2434 but BOOL is not.
2436 3. The pcre_config() function was treating the PCRE_MATCH_LIMIT and
2437 PCRE_MATCH_LIMIT_RECURSION values as ints, when they should be long ints.
2439 4. The pcregrep documentation said spaces were inserted as well as colons (or
2440 hyphens) following file names and line numbers when outputting matching
2441 lines. This is not true; no spaces are inserted. I have also clarified the
2442 wording for the --colour (or --color) option.
2444 5. In pcregrep, when --colour was used with -o, the list of matching strings
2445 was not coloured; this is different to GNU grep, so I have changed it to be
2446 the same.
2448 6. When --colo(u)r was used in pcregrep, only the first matching substring in
2449 each matching line was coloured. Now it goes on to look for further matches
2450 of any of the test patterns, which is the same behaviour as GNU grep.
2452 7. A pattern that could match an empty string could cause pcregrep to loop; it
2453 doesn't make sense to accept an empty string match in pcregrep, so I have
2454 locked it out (using PCRE's PCRE_NOTEMPTY option). By experiment, this
2455 seems to be how GNU grep behaves. [But see later change 40 for release
2456 8.33.]
2458 8. The pattern (?(?=.*b)b|^) was incorrectly compiled as "match must be at
2459 start or after a newline", because the conditional assertion was not being
2460 correctly handled. The rule now is that both the assertion and what follows
2461 in the first alternative must satisfy the test.
2463 9. If auto-callout was enabled in a pattern with a conditional group whose
2464 condition was an assertion, PCRE could crash during matching, both with
2465 pcre_exec() and pcre_dfa_exec().
2467 10. The PCRE_DOLLAR_ENDONLY option was not working when pcre_dfa_exec() was
2468 used for matching.
2470 11. Unicode property support in character classes was not working for
2471 characters (bytes) greater than 127 when not in UTF-8 mode.
2473 12. Added the -M command line option to pcretest.
2475 14. Added the non-standard REG_NOTEMPTY option to the POSIX interface.
2477 15. Added the PCRE_NO_START_OPTIMIZE match-time option.
2479 16. Added comments and documentation about mis-use of no_arg in the C++
2480 wrapper.
2482 17. Implemented support for UTF-8 encoding in EBCDIC environments, a patch
2483 from Martin Jerabek that uses macro names for all relevant character and
2484 string constants.
2486 18. Added to pcre_internal.h two configuration checks: (a) If both EBCDIC and
2487 SUPPORT_UTF8 are set, give an error; (b) If SUPPORT_UCP is set without
2488 SUPPORT_UTF8, define SUPPORT_UTF8. The "configure" script handles both of
2489 these, but not everybody uses configure.
2491 19. A conditional group that had only one branch was not being correctly
2492 recognized as an item that could match an empty string. This meant that an
2493 enclosing group might also not be so recognized, causing infinite looping
2494 (and probably a segfault) for patterns such as ^"((?(?=[a])[^"])|b)*"$
2495 with the subject "ab", where knowledge that the repeated group can match
2496 nothing is needed in order to break the loop.
2498 20. If a pattern that was compiled with callouts was matched using pcre_dfa_
2499 exec(), but without supplying a callout function, matching went wrong.
2501 21. If PCRE_ERROR_MATCHLIMIT occurred during a recursion, there was a memory
2502 leak if the size of the offset vector was greater than 30. When the vector
2503 is smaller, the saved offsets during recursion go onto a local stack
2504 vector, but for larger vectors malloc() is used. It was failing to free
2505 when the recursion yielded PCRE_ERROR_MATCH_LIMIT (or any other "abnormal"
2506 error, in fact).
2508 22. There was a missing #ifdef SUPPORT_UTF8 round one of the variables in the
2509 heapframe that is used only when UTF-8 support is enabled. This caused no
2510 problem, but was untidy.
2512 23. Steven Van Ingelgem's patch to CMakeLists.txt to change the name
2513 CMAKE_BINARY_DIR to PROJECT_BINARY_DIR so that it works when PCRE is
2514 included within another project.
2516 24. Steven Van Ingelgem's patches to add more options to the CMake support,
2517 slightly modified by me:
2519 (a) PCRE_BUILD_TESTS can be set OFF not to build the tests, including
2520 not building pcregrep.
2522 (b) PCRE_BUILD_PCREGREP can be see OFF not to build pcregrep, but only
2523 if PCRE_BUILD_TESTS is also set OFF, because the tests use pcregrep.
2525 25. Forward references, both numeric and by name, in patterns that made use of
2526 duplicate group numbers, could behave incorrectly or give incorrect errors,
2527 because when scanning forward to find the reference group, PCRE was not
2528 taking into account the duplicate group numbers. A pattern such as
2529 ^X(?3)(a)(?|(b)|(q))(Y) is an example.
2531 26. Changed a few more instances of "const unsigned char *" to USPTR, making
2532 the feature of a custom pointer more persuasive (as requested by a user).
2534 27. Wrapped the definitions of fileno and isatty for Windows, which appear in
2535 pcretest.c, inside #ifndefs, because it seems they are sometimes already
2536 pre-defined.
2538 28. Added support for (*UTF8) at the start of a pattern.
2540 29. Arrange for flags added by the "release type" setting in CMake to be shown
2541 in the configuration summary.
2544 Version 7.8 05-Sep-08
2545 ---------------------
2547 1. Replaced UCP searching code with optimized version as implemented for Ad
2548 Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
2549 stage table and inline lookup instead of a function, giving speed ups of 2
2550 to 5 times on some simple patterns that I tested. Permission was given to
2551 distribute the MultiStage2.py script that generates the tables (it's not in
2552 the tarball, but is in the Subversion repository).
2554 2. Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
2555 scripts.
2557 3. Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
2558 a group with a zero qualifier. The result of the study could be incorrect,
2559 or the function might crash, depending on the pattern.
2561 4. Caseless matching was not working for non-ASCII characters in back
2562 references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
2563 It now works when Unicode Property Support is available.
2565 5. In pcretest, an escape such as \x{de} in the data was always generating
2566 a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
2567 non-UTF-8 mode. If the value is greater than 255, it gives a warning about
2568 truncation.
2570 6. Minor bugfix in pcrecpp.cc (change "" == ... to NULL == ...).
2572 7. Added two (int) casts to pcregrep when printing the difference of two
2573 pointers, in case they are 64-bit values.
2575 8. Added comments about Mac OS X stack usage to the pcrestack man page and to
2576 test 2 if it fails.
2578 9. Added PCRE_CALL_CONVENTION just before the names of all exported functions,
2579 and a #define of that name to empty if it is not externally set. This is to
2580 allow users of MSVC to set it if necessary.
2582 10. The PCRE_EXP_DEFN macro which precedes exported functions was missing from
2583 the convenience functions in the pcre_get.c source file.
2585 11. An option change at the start of a pattern that had top-level alternatives
2586 could cause overwriting and/or a crash. This command provoked a crash in
2587 some environments:
2589 printf "/(?i)[\xc3\xa9\xc3\xbd]|[\xc3\xa9\xc3\xbdA]/8\n" | pcretest
2591 This potential security problem was recorded as CVE-2008-2371.
2593 12. For a pattern where the match had to start at the beginning or immediately
2594 after a newline (e.g /.*anything/ without the DOTALL flag), pcre_exec() and
2595 pcre_dfa_exec() could read past the end of the passed subject if there was
2596 no match. To help with detecting such bugs (e.g. with valgrind), I modified
2597 pcretest so that it places the subject at the end of its malloc-ed buffer.
2599 13. The change to pcretest in 12 above threw up a couple more cases when pcre_
2600 exec() might read past the end of the data buffer in UTF-8 mode.
2602 14. A similar bug to 7.3/2 existed when the PCRE_FIRSTLINE option was set and
2603 the data contained the byte 0x85 as part of a UTF-8 character within its
2604 first line. This applied both to normal and DFA matching.
2606 15. Lazy qualifiers were not working in some cases in UTF-8 mode. For example,
2607 /^[^d]*?$/8 failed to match "abc".
2609 16. Added a missing copyright notice to pcrecpp_internal.h.
2611 17. Make it more clear in the documentation that values returned from
2612 pcre_exec() in ovector are byte offsets, not character counts.
2614 18. Tidied a few places to stop certain compilers from issuing warnings.
2616 19. Updated the Virtual Pascal + BCC files to compile the latest v7.7, as
2617 supplied by Stefan Weber. I made a further small update for 7.8 because
2618 there is a change of source arrangements: the pcre_searchfuncs.c module is
2619 replaced by pcre_ucd.c.
2622 Version 7.7 07-May-08
2623 ---------------------
2625 1. Applied Craig's patch to sort out a long long problem: "If we can't convert
2626 a string to a long long, pretend we don't even have a long long." This is
2627 done by checking for the strtoq, strtoll, and _strtoi64 functions.
2629 2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
2630 pre-7.6 versions, which defined a global no_arg variable instead of putting
2631 it in the RE class. (See also #8 below.)
2633 3. Remove a line of dead code, identified by coverity and reported by Nuno
2634 Lopes.
2636 4. Fixed two related pcregrep bugs involving -r with --include or --exclude:
2638 (1) The include/exclude patterns were being applied to the whole pathnames
2639 of files, instead of just to the final components.
2641 (2) If there was more than one level of directory, the subdirectories were
2642 skipped unless they satisfied the include/exclude conditions. This is
2643 inconsistent with GNU grep (and could even be seen as contrary to the
2644 pcregrep specification - which I improved to make it absolutely clear).
2645 The action now is always to scan all levels of directory, and just
2646 apply the include/exclude patterns to regular files.
2648 5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used
2649 --exclude_dir in the tests to avoid scanning .svn directories.
2651 6. Applied Craig's patch to the QuoteMeta function so that it escapes the
2652 NUL character as backslash + 0 rather than backslash + NUL, because PCRE
2653 doesn't support NULs in patterns.
2655 7. Added some missing "const"s to declarations of static tables in
2656 pcre_compile.c and pcre_dfa_exec.c.
2658 8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
2659 caused by fix #2 above. (Subsequently also a second patch to fix the
2660 first patch. And a third patch - this was a messy problem.)
2662 9. Applied Craig's patch to remove the use of push_back().
2664 10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
2665 matching function regexec().
2667 11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
2668 which, however, unlike Perl's \g{...}, are subroutine calls, not back
2669 references. PCRE supports relative numbers with this syntax (I don't think
2670 Oniguruma does).
2672 12. Previously, a group with a zero repeat such as (...){0} was completely
2673 omitted from the compiled regex. However, this means that if the group
2674 was called as a subroutine from elsewhere in the pattern, things went wrong
2675 (an internal error was given). Such groups are now left in the compiled
2676 pattern, with a new opcode that causes them to be skipped at execution
2677 time.
2679 13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
2680 to the way PCRE behaves:
2682 (a) A lone ] character is dis-allowed (Perl treats it as data).
2684 (b) A back reference to an unmatched subpattern matches an empty string
2685 (Perl fails the current match path).
2687 (c) A data ] in a character class must be notated as \] because if the
2688 first data character in a class is ], it defines an empty class. (In
2689 Perl it is not possible to have an empty class.) The empty class []
2690 never matches; it forces failure and is equivalent to (*FAIL) or (?!).
2691 The negative empty class [^] matches any one character, independently
2692 of the DOTALL setting.
2694 14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
2695 non-existent subpattern following a character class starting with ']' and
2696 containing () gave an internal compiling error instead of "reference to
2697 non-existent subpattern". Fortunately, when the pattern did exist, the
2698 compiled code was correct. (When scanning forwards to check for the
2699 existence of the subpattern, it was treating the data ']' as terminating
2700 the class, so got the count wrong. When actually compiling, the reference
2701 was subsequently set up correctly.)
2703 15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
2704 it was being rejected as not supported by pcre_dfa_exec(), even though
2705 other assertions are supported. I have made pcre_dfa_exec() support
2706 (*FAIL).
2708 16. The implementation of 13c above involved the invention of a new opcode,
2709 OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
2710 cannot be changed at match time, I realized I could make a small
2711 improvement to matching performance by compiling OP_ALLANY instead of
2712 OP_ANY for "." when DOTALL was set, and then removing the runtime tests
2713 on the OP_ANY path.
2715 17. Compiling pcretest on Windows with readline support failed without the
2716 following two fixes: (1) Make the unistd.h include conditional on
2717 HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
2719 18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
2720 ncurses library to be included for pcretest when ReadLine support is
2721 requested, but also to allow for it to be overridden. This patch came from
2722 Daniel Bergström.
2724 19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
2725 as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
2726 any errors with the current Unicode tables. Thanks to Peter Kankowski for
2727 spotting this.
2730 Version 7.6 28-Jan-08
2731 ---------------------
2733 1. A character class containing a very large number of characters with
2734 codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
2735 overflow.
2737 2. Patch to cut out the "long long" test in pcrecpp_unittest when
2738 HAVE_LONG_LONG is not defined.
2740 3. Applied Christian Ehrlicher's patch to update the CMake build files to
2741 bring them up to date and include new features. This patch includes:
2743 - Fixed PH's badly added libz and libbz2 support.
2744 - Fixed a problem with static linking.
2745 - Added pcredemo. [But later removed - see 7 below.]
2746 - Fixed dftables problem and added an option.
2747 - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
2749 - Added readline support for pcretest.
2750 - Added an listing of the option settings after cmake has run.
2752 4. A user submitted a patch to Makefile that makes it easy to create
2753 "pcre.dll" under mingw when using Configure/Make. I added stuff to
2754 Makefile.am that cause it to include this special target, without
2755 affecting anything else. Note that the same mingw target plus all
2756 the other distribution libraries and programs are now supported
2757 when configuring with CMake (see 6 below) instead of with
2758 Configure/Make.
2760 5. Applied Craig's patch that moves no_arg into the RE class in the C++ code.
2761 This is an attempt to solve the reported problem "pcrecpp::no_arg is not
2762 exported in the Windows port". It has not yet been confirmed that the patch
2763 solves the problem, but it does no harm.
2765 6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
2766 NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
2767 with CMake, and also correct the comment about stack recursion.
2769 7. Remove the automatic building of pcredemo from the ./configure system and
2770 from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
2771 of a program that users should build themselves after PCRE is installed, so
2772 building it automatically is not really right. What is more, it gave
2773 trouble in some build environments.
2775 8. Further tidies to CMakeLists.txt from Sheri and Christian.
2778 Version 7.5 10-Jan-08
2779 ---------------------
2781 1. Applied a patch from Craig: "This patch makes it possible to 'ignore'
2782 values in parens when parsing an RE using the C++ wrapper."
2784 2. Negative specials like \S did not work in character classes in UTF-8 mode.
2785 Characters greater than 255 were excluded from the class instead of being
2786 included.
2788 3. The same bug as (2) above applied to negated POSIX classes such as
2789 [:^space:].
2791 4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
2792 defined or documented. It seems to have been a typo for PCRE_STATIC, so
2793 I have changed it.
2795 5. The construct (?&) was not diagnosed as a syntax error (it referenced the
2796 first named subpattern) and a construct such as (?&a) would reference the
2797 first named subpattern whose name started with "a" (in other words, the
2798 length check was missing). Both these problems are fixed. "Subpattern name
2799 expected" is now given for (?&) (a zero-length name), and this patch also
2800 makes it give the same error for \k'' (previously it complained that that
2801 was a reference to a non-existent subpattern).
2803 6. The erroneous patterns (?+-a) and (?-+a) give different error messages;
2804 this is right because (?- can be followed by option settings as well as by
2805 digits. I have, however, made the messages clearer.
2807 7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
2808 than the number used in the conditional) now cause a compile-time error.
2809 This is actually not compatible with Perl, which accepts such patterns, but
2810 treats the conditional as always being FALSE (as PCRE used to), but it
2811 seems to me that giving a diagnostic is better.
2813 8. Change "alphameric" to the more common word "alphanumeric" in comments
2814 and messages.
2816 9. Fix two occurrences of "backslash" in comments that should have been
2817 "backspace".
2819 10. Remove two redundant lines of code that can never be obeyed (their function
2820 was moved elsewhere).
2822 11. The program that makes PCRE's Unicode character property table had a bug
2823 which caused it to generate incorrect table entries for sequences of
2824 characters that have the same character type, but are in different scripts.
2825 It amalgamated them into a single range, with the script of the first of
2826 them. In other words, some characters were in the wrong script. There were
2827 thirteen such cases, affecting characters in the following ranges:
2829 U+002b0 - U+002c1
2830 U+0060c - U+0060d
2831 U+0061e - U+00612
2832 U+0064b - U+0065e
2833 U+0074d - U+0076d
2834 U+01800 - U+01805
2835 U+01d00 - U+01d77
2836 U+01d9b - U+01dbf
2837 U+0200b - U+0200f
2838 U+030fc - U+030fe
2839 U+03260 - U+0327f
2840 U+0fb46 - U+0fbb1
2841 U+10450 - U+1049d
2843 12. The -o option (show only the matching part of a line) for pcregrep was not
2844 compatible with GNU grep in that, if there was more than one match in a
2845 line, it showed only the first of them. It now behaves in the same way as
2846 GNU grep.
2848 13. If the -o and -v options were combined for pcregrep, it printed a blank
2849 line for every non-matching line. GNU grep prints nothing, and pcregrep now
2850 does the same. The return code can be used to tell if there were any
2851 non-matching lines.
2853 14. Added --file-offsets and --line-offsets to pcregrep.
2855 15. The pattern (?=something)(?R) was not being diagnosed as a potentially
2856 infinitely looping recursion. The bug was that positive lookaheads were not
2857 being skipped when checking for a possible empty match (negative lookaheads
2858 and both kinds of lookbehind were skipped).
2860 16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
2861 inclusion of <windows.h> to before rather than after the definition of
2862 INVALID_FILE_ATTRIBUTES (patch from David Byron).
2864 17. Specifying a possessive quantifier with a specific limit for a Unicode
2865 character property caused pcre_compile() to compile bad code, which led at
2866 runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
2867 are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
2868 caused the error; without that there was no problem.
2870 18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
2872 19. Added --enable-pcretest-libreadline.
2874 20. In pcrecpp.cc, the variable 'count' was incremented twice in
2875 RE::GlobalReplace(). As a result, the number of replacements returned was
2876 double what it should be. I removed one of the increments, but Craig sent a
2877 later patch that removed the other one (the right fix) and added unit tests
2878 that check the return values (which was not done before).
2880 21. Several CMake things:
2882 (1) Arranged that, when cmake is used on Unix, the libraries end up with
2883 the names libpcre and libpcreposix, not just pcre and pcreposix.
2885 (2) The above change means that pcretest and pcregrep are now correctly
2886 linked with the newly-built libraries, not previously installed ones.
2890 22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
2891 crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
2892 UTF-8 newline character). The key issue is that the pattern starts .*;
2893 this means that the match must be either at the beginning, or after a
2894 newline. The bug was in the code for advancing after a failed match and
2895 checking that the new position followed a newline. It was not taking
2896 account of UTF-8 characters correctly.
2898 23. PCRE was behaving differently from Perl in the way it recognized POSIX
2899 character classes. PCRE was not treating the sequence [:...:] as a
2900 character class unless the ... were all letters. Perl, however, seems to
2901 allow any characters between [: and :], though of course it rejects as
2902 unknown any "names" that contain non-letters, because all the known class
2903 names consist only of letters. Thus, Perl gives an error for [[:1234:]],
2904 for example, whereas PCRE did not - it did not recognize a POSIX character
2905 class. This seemed a bit dangerous, so the code has been changed to be
2906 closer to Perl. The behaviour is not identical to Perl, because PCRE will
2907 diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
2908 treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
2909 Perl does, and where it didn't before.
2911 24. Rewrite so as to remove the single use of %n from pcregrep because in some
2912 Windows environments %n is disabled by default.
2915 Version 7.4 21-Sep-07
2916 ---------------------
2918 1. Change 7.3/28 was implemented for classes by looking at the bitmap. This
2919 means that a class such as [\s] counted as "explicit reference to CR or
2920 LF". That isn't really right - the whole point of the change was to try to
2921 help when there was an actual mention of one of the two characters. So now
2922 the change happens only if \r or \n (or a literal CR or LF) character is
2923 encountered.
2925 2. The 32-bit options word was also used for 6 internal flags, but the numbers
2926 of both had grown to the point where there were only 3 bits left.
2927 Fortunately, there was spare space in the data structure, and so I have
2928 moved the internal flags into a new 16-bit field to free up more option
2929 bits.
2931 3. The appearance of (?J) at the start of a pattern set the DUPNAMES option,
2932 but did not set the internal JCHANGED flag - either of these is enough to
2933 control the way the "get" function works - but the PCRE_INFO_JCHANGED
2934 facility is supposed to tell if (?J) was ever used, so now (?J) at the
2935 start sets both bits.
2937 4. Added options (at build time, compile time, exec time) to change \R from
2938 matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
2940 5. doc/pcresyntax.html was missing from the distribution.
2942 6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
2943 compatibility, even though it is no longer used.
2945 7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
2946 strtoull to pcrecpp.cc to select the available functions in WIN32 when the
2947 windows.h file is present (where different names are used). [This was
2948 reversed later after testing - see 16 below.]
2950 8. Changed all #include <config.h> to #include "config.h". There were also
2951 some further <pcre.h> cases that I changed to "pcre.h".
2953 9. When pcregrep was used with the --colour option, it missed the line ending
2954 sequence off the lines that it output.
2956 10. It was pointed out to me that arrays of string pointers cause lots of
2957 relocations when a shared library is dynamically loaded. A technique of
2958 using a single long string with a table of offsets can drastically reduce
2959 these. I have refactored PCRE in four places to do this. The result is
2960 dramatic:
2962 Originally: 290
2963 After changing UCP table: 187
2964 After changing error message table: 43
2965 After changing table of "verbs" 36
2966 After changing table of Posix names 22
2968 Thanks to the folks working on Gregex for glib for this insight.
2970 11. --disable-stack-for-recursion caused compiling to fail unless -enable-
2971 unicode-properties was also set.
2973 12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
2975 13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
2976 checked only for CRLF.
2978 14. Added casts to pcretest.c to avoid compiler warnings.
2980 15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
2982 16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
2983 and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
2984 entirely. This removes changes made in 7 above.
2986 17. The CMake files have been updated, and there is now more information about
2987 building with CMake in the NON-UNIX-USE document.
2990 Version 7.3 28-Aug-07
2991 ---------------------
2993 1. In the rejigging of the build system that eventually resulted in 7.1, the
2994 line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
2995 brackets there is not right, since it causes compilers to look for an
2996 installed pcre.h, not the version that is in the source that is being
2997 compiled (which of course may be different). I have changed it back to:
2999 #include "pcre.h"
3001 I have a vague recollection that the change was concerned with compiling in
3002 different directories, but in the new build system, that is taken care of
3003 by the VPATH setting the Makefile.
3005 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
3006 when the subject happened to end in the byte 0x85 (e.g. if the last
3007 character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
3008 characters but of course it shouldn't be taken as a newline when it is part
3009 of another character. The bug was that, for an unlimited repeat of . in
3010 not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
3011 characters when looking for a newline.
3013 3. A small performance improvement in the DOTALL UTF-8 mode .* case.
3015 4. Debugging: adjusted the names of opcodes for different kinds of parentheses
3016 in debug output.
3018 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
3019 long printing in the pcrecpp unittest when running under MinGW.
3021 6. ESC_K was left out of the EBCDIC table.
3023 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
3024 parentheses; I made it 1000, which seemed large enough. Unfortunately, the
3025 limit also applies to "virtual nesting" when a pattern is recursive, and in
3026 this case 1000 isn't so big. I have been able to remove this limit at the
3027 expense of backing off one optimization in certain circumstances. Normally,
3028 when pcre_exec() would call its internal match() function recursively and
3029 immediately return the result unconditionally, it uses a "tail recursion"
3030 feature to save stack. However, when a subpattern that can match an empty
3031 string has an unlimited repetition quantifier, it no longer makes this
3032 optimization. That gives it a stack frame in which to save the data for
3033 checking that an empty string has been matched. Previously this was taken
3034 from the 1000-entry workspace that had been reserved. So now there is no
3035 explicit limit, but more stack is used.
3037 8. Applied Daniel's patches to solve problems with the import/export magic
3038 syntax that is required for Windows, and which was going wrong for the
3039 pcreposix and pcrecpp parts of the library. These were overlooked when this
3040 problem was solved for the main library.
3042 9. There were some crude static tests to avoid integer overflow when computing
3043 the size of patterns that contain repeated groups with explicit upper
3044 limits. As the maximum quantifier is 65535, the maximum group length was
3045 set at 30,000 so that the product of these two numbers did not overflow a
3046 32-bit integer. However, it turns out that people want to use groups that
3047 are longer than 30,000 bytes (though not repeat them that many times).
3048 Change 7.0/17 (the refactoring of the way the pattern size is computed) has
3049 made it possible to implement the integer overflow checks in a much more
3050 dynamic way, which I have now done. The artificial limitation on group
3051 length has been removed - we now have only the limit on the total length of
3052 the compiled pattern, which depends on the LINK_SIZE setting.
3054 10. Fixed a bug in the documentation for get/copy named substring when
3055 duplicate names are permitted. If none of the named substrings are set, the
3056 functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
3057 empty string.
3059 11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
3060 instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
3061 because the ] is interpreted as the first data character and the
3062 terminating ] is not found. PCRE has been made compatible with Perl in this
3063 regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
3064 cause memory overwriting.
3066 10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
3067 string has been matched (to stop an infinite loop). It was not recognizing
3068 a conditional subpattern that could match an empty string if that
3069 subpattern was within another subpattern. For example, it looped when
3070 trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the
3071 condition was not nested. This bug has been fixed.
3073 12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
3074 past the start of the subject in the presence of bytes with the top bit
3075 set, for example "\x8aBCD".
3077 13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
3078 (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
3080 14. Optimized (?!) to (*FAIL).
3082 15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
3083 This restricts code points to be within the range 0 to 0x10FFFF, excluding
3084 the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
3085 full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
3086 does: it's just the validity check that is more restrictive.
3088 16. Inserted checks for integer overflows during escape sequence (backslash)
3089 processing, and also fixed erroneous offset values for syntax errors during
3090 backslash processing.
3092 17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
3093 for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
3095 18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
3096 caused an overrun.
3098 19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
3099 something other than just ASCII characters) inside a group that had an
3100 unlimited repeat caused a loop at compile time (while checking to see
3101 whether the group could match an empty string).
3103 20. Debugging a pattern containing \p or \P could cause a crash. For example,
3104 [\P{Any}] did so. (Error in the code for printing property names.)
3106 21. An orphan \E inside a character class could cause a crash.
3108 22. A repeated capturing bracket such as (A)? could cause a wild memory
3109 reference during compilation.
3111 23. There are several functions in pcre_compile() that scan along a compiled
3112 expression for various reasons (e.g. to see if it's fixed length for look
3113 behind). There were bugs in these functions when a repeated \p or \P was
3114 present in the pattern. These operators have additional parameters compared
3115 with \d, etc, and these were not being taken into account when moving along
3116 the compiled data. Specifically:
3118 (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
3119 length.
3121 (b) An item such as \pL+ within a repeated group could cause crashes or
3122 loops.
3124 (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
3125 "reference to non-existent subpattern" error.
3127 (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
3129 24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
3130 characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
3132 25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
3134 26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
3135 character were causing crashes (broken optimization).
3137 27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
3138 \p or \P) caused a compile-time loop.
3140 28. More problems have arisen in unanchored patterns when CRLF is a valid line
3141 break. For example, the unstudied pattern [\r\n]A does not match the string
3142 "\r\nA" because change 7.0/46 below moves the current point on by two
3143 characters after failing to match at the start. However, the pattern \nA
3144 *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
3145 the same is true. There doesn't seem any very clean way out of this, but
3146 what I have chosen to do makes the common cases work: PCRE now takes note
3147 of whether there can be an explicit match for \r or \n anywhere in the
3148 pattern, and if so, 7.0/46 no longer applies. As part of this change,
3149 there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
3150 pattern has explicit CR or LF references.
3152 29. Added (*CR) etc for changing newline setting at start of pattern.
3155 Version 7.2 19-Jun-07
3156 ---------------------
3158 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
3159 which is apparently normally available under Windows.
3161 2. Re-jig the pcregrep tests with different newline settings in an attempt
3162 to make them independent of the local environment's newline setting.
3164 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
3166 4. Some of the "internals" tests were previously cut out when the link size
3167 was not 2, because the output contained actual offsets. The recent new
3168 "Z" feature of pcretest means that these can be cut out, making the tests
3169 usable with all link sizes.
3171 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
3172 stack recursion. This gives a massive performance boost under BSD, but just
3173 a small improvement under Linux. However, it saves one field in the frame
3174 in all cases.
3176 6. Added more features from the forthcoming Perl 5.10:
3178 (a) (?-n) (where n is a string of digits) is a relative subroutine or
3179 recursion call. It refers to the nth most recently opened parentheses.
3181 (b) (?+n) is also a relative subroutine call; it refers to the nth next
3182 to be opened parentheses.
3184 (c) Conditions that refer to capturing parentheses can be specified
3185 relatively, for example, (?(-2)... or (?(+3)...
3187 (d) \K resets the start of the current match so that everything before
3188 is not part of it.
3190 (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
3192 (f) \g{name} is another synonym - part of Perl 5.10's unification of
3193 reference syntax.
3195 (g) (?| introduces a group in which the numbering of parentheses in each
3196 alternative starts with the same number.
3198 (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
3200 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
3203 8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not
3204 terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
3205 for detecting groups that can match an empty string.
3207 9. A pattern with a very large number of alternatives (more than several
3208 hundred) was running out of internal workspace during the pre-compile
3209 phase, where pcre_compile() figures out how much memory will be needed. A
3210 bit of new cunning has reduced the workspace needed for groups with
3211 alternatives. The 1000-alternative test pattern now uses 12 bytes of
3212 workspace instead of running out of the 4096 that are available.
3214 10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
3216 11. Applied patch from Google to remove an optimization that didn't quite work.
3217 The report of the bug said:
3219 pcrecpp::RE("a*").FullMatch("aaa") matches, while
3220 pcrecpp::RE("a*?").FullMatch("aaa") does not, and
3221 pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
3223 12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
3224 it matched the wrong number of bytes.
3227 Version 7.1 24-Apr-07
3228 ---------------------
3230 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
3231 that is more "standard", making use of automake and other Autotools. There
3232 is some re-arrangement of the files and adjustment of comments consequent
3233 on this.
3235 2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
3236 for recursive directory scanning broke on some systems because the files
3237 are not scanned in any specific order and on different systems the order
3238 was different. A call to "sort" has been inserted into RunGrepTest for the
3239 approprate test as a short-term fix. In the longer term there may be an
3240 alternative.
3242 3. I had an email from Eric Raymond about problems translating some of PCRE's
3243 man pages to HTML (despite the fact that I distribute HTML pages, some
3244 people do their own conversions for various reasons). The problems
3245 concerned the use of low-level troff macros .br and .in. I have therefore
3246 removed all such uses from the man pages (some were redundant, some could
3247 be replaced by .nf/.fi pairs). The 132html script that I use to generate
3248 HTML has been updated to handle .nf/.fi and to complain if it encounters
3249 .br or .in.
3251 4. Updated comments in configure.ac that get placed in config.h.in and also
3252 arranged for config.h to be included in the distribution, with the name
3253 config.h.generic, for the benefit of those who have to compile without
3254 Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
3256 5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
3257 Weber: (1) pcre_internal.h was missing some function renames; (2) updated
3258 makevp.bat for the current PCRE, using the additional files
3259 makevp_c.txt, makevp_l.txt, and pcregexp.pas.
3261 6. A Windows user reported a minor discrepancy with test 2, which turned out
3262 to be caused by a trailing space on an input line that had got lost in his
3263 copy. The trailing space was an accident, so I've just removed it.
3265 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
3266 that is needed.
3268 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
3269 as "const" (a) because they are and (b) because it helps the PHP
3270 maintainers who have recently made a script to detect big data structures
3271 in the php code that should be moved to the .rodata section. I remembered
3272 to update Builducptable as well, so it won't revert if ucptable.h is ever
3273 re-created.
3275 9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
3276 pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
3277 order to be able to cut out the UTF-8 tables in the latter when UTF-8
3278 support is not required. This saves 1.5-2K of code, which is important in
3279 some applications.
3281 Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
3282 so as not to refer to the tables, even though these functions will never be
3283 called when UTF-8 support is disabled. Otherwise there are problems with a
3284 shared library.
3286 10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
3288 (a) It was defining its arguments as char * instead of void *.
3290 (b) It was assuming that all moves were upwards in memory; this was true
3291 a long time ago when I wrote it, but is no longer the case.
3293 The emulated memove() is provided for those environments that have neither
3294 memmove() nor bcopy(). I didn't think anyone used it these days, but that
3295 is clearly not the case, as these two bugs were recently reported.
3297 11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
3298 and Detrail to create the HTML documentation, the .txt form of the man
3299 pages, and it removes trailing spaces from listed files. It also creates
3300 pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
3301 case, it wraps all the #defines with #ifndefs. This script should be run
3302 before "make dist".
3304 12. Fixed two fairly obscure bugs concerned with quantified caseless matching
3305 with Unicode property support.
3307 (a) For a maximizing quantifier, if the two different cases of the
3308 character were of different lengths in their UTF-8 codings (there are
3309 some cases like this - I found 11), and the matching function had to
3310 back up over a mixture of the two cases, it incorrectly assumed they
3311 were both the same length.
3313 (b) When PCRE was configured to use the heap rather than the stack for
3314 recursion during matching, it was not correctly preserving the data for
3315 the other case of a UTF-8 character when checking ahead for a match
3316 while processing a minimizing repeat. If the check also involved
3317 matching a wide character, but failed, corruption could cause an
3318 erroneous result when trying to check for a repeat of the original
3319 character.
3321 13. Some tidying changes to the testing mechanism:
3323 (a) The RunTest script now detects the internal link size and whether there
3324 is UTF-8 and UCP support by running ./pcretest -C instead of relying on
3325 values substituted by "configure". (The RunGrepTest script already did
3326 this for UTF-8.) The configure.ac script no longer substitutes the
3327 relevant variables.
3329 (b) The debugging options /B and /D in pcretest show the compiled bytecode
3330 with length and offset values. This means that the output is different
3331 for different internal link sizes. Test 2 is skipped for link sizes
3332 other than 2 because of this, bypassing the problem. Unfortunately,
3333 there was also a test in test 3 (the locale tests) that used /B and
3334 failed for link sizes other than 2. Rather than cut the whole test out,
3335 I have added a new /Z option to pcretest that replaces the length and
3336 offset values with spaces. This is now used to make test 3 independent
3337 of link size. (Test 2 will be tidied up later.)
3339 14. If erroroffset was passed as NULL to pcre_compile, it provoked a
3340 segmentation fault instead of returning the appropriate error message.
3342 15. In multiline mode when the newline sequence was set to "any", the pattern
3343 ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
3344 This doesn't seem right; it now treats the CRLF combination as the line
3345 ending, and so does not match in that case. It's only a pattern such as ^$
3346 that would hit this one: something like ^ABC$ would have failed after \r
3347 and then tried again after \r\n.
3349 16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
3350 in an attempt to make files that differ only in their line terminators
3351 compare equal. This works on Linux.
3353 17. Under certain error circumstances pcregrep might try to free random memory
3354 as it exited. This is now fixed, thanks to valgrind.
3356 19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
3357 "abc\r\n\r\n", it found an unwanted second match after the second \r. This
3358 was because its rules for how to advance for /g after matching an empty
3359 string at the end of a line did not allow for this case. They now check for
3360 it specially.
3362 20. pcretest is supposed to handle patterns and data of any length, by
3363 extending its buffers when necessary. It was getting this wrong when the
3364 buffer for a data line had to be extended.
3366 21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
3367 CRLF as a newline sequence.
3369 22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
3370 out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
3371 I have nevertheless tidied it up.
3373 23. Added some casts to kill warnings from HP-UX ia64 compiler.
3375 24. Added a man page for pcre-config.
3378 Version 7.0 19-Dec-06
3379 ---------------------
3381 1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
3382 moving to gcc 4.1.1.
3384 2. The -S option for pcretest uses setrlimit(); I had omitted to #include
3385 sys/time.h, which is documented as needed for this function. It doesn't
3386 seem to matter on Linux, but it showed up on some releases of OS X.
3388 3. It seems that there are systems where bytes whose values are greater than
3389 127 match isprint() in the "C" locale. The "C" locale should be the
3390 default when a C program starts up. In most systems, only ASCII printing
3391 characters match isprint(). This difference caused the output from pcretest
3392 to vary, making some of the tests fail. I have changed pcretest so that:
3394 (a) When it is outputting text in the compiled version of a pattern, bytes
3395 other than 32-126 are always shown as hex escapes.
3397 (b) When it is outputting text that is a matched part of a subject string,
3398 it does the same, unless a different locale has been set for the match
3399 (using the /L modifier). In this case, it uses isprint() to decide.
3401 4. Fixed a major bug that caused incorrect computation of the amount of memory
3402 required for a compiled pattern when options that changed within the
3403 pattern affected the logic of the preliminary scan that determines the
3404 length. The relevant options are -x, and -i in UTF-8 mode. The result was
3405 that the computed length was too small. The symptoms of this bug were
3406 either the PCRE error "internal error: code overflow" from pcre_compile(),
3407 or a glibc crash with a message such as "pcretest: free(): invalid next
3408 size (fast)". Examples of patterns that provoked this bug (shown in
3409 pcretest format) are:
3411 /(?-x: )/x
3412 /(?x)(?-x: \s*#\s*)/
3413 /((?i)[\x{c0}])/8
3414 /(?i:[\x{c0}])/8
3416 HOWEVER: Change 17 below makes this fix obsolete as the memory computation
3417 is now done differently.
3419 5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
3420 wrapper classes; (b) implement a new function in the C++ scanner that is
3421 more efficient than the old way of doing things because it avoids levels of
3422 recursion in the regex matching; (c) add a paragraph to the documentation
3423 for the FullMatch() function.
3425 6. The escape sequence \n was being treated as whatever was defined as
3426 "newline". Not only was this contrary to the documentation, which states
3427 that \n is character 10 (hex 0A), but it also went horribly wrong when
3428 "newline" was defined as CRLF. This has been fixed.
3430 7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
3431 was being set to -1 for the "end of line" case (supposedly a value that no
3432 character can have). Though this value is never used (the check for end of
3433 line is "zero bytes in current character"), it caused compiler complaints.
3434 I've changed it to 0xffffffff.
3436 8. In pcre_version.c, the version string was being built by a sequence of
3437 C macros that, in the event of PCRE_PRERELEASE being defined as an empty
3438 string (as it is for production releases) called a macro with an empty
3439 argument. The C standard says the result of this is undefined. The gcc
3440 compiler treats it as an empty string (which was what was wanted) but it is
3441 reported that Visual C gives an error. The source has been hacked around to
3442 avoid this problem.
3444 9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
3445 builds of pcretest, and changed the call to _setmode() to use _O_BINARY
3446 instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
3447 of them did).
3449 10. Originally, pcretest opened its input and output without "b"; then I was
3450 told that "b" was needed in some environments, so it was added for release
3451 5.0 to both the input and output. (It makes no difference on Unix-like
3452 systems.) Later I was told that it is wrong for the input on Windows. I've
3453 now abstracted the modes into two macros, to make it easier to fiddle with
3454 them, and removed "b" from the input mode under Windows.
3456 11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
3458 12. Added -help and --help to pcretest as an official way of being reminded
3459 of the options.
3461 13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
3462 and pcrecpp.cc because they annoy compilers at high warning levels.
3464 14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
3466 15. Fixed an occurrence of == in configure.ac that should have been = (shell
3467 scripts are not C programs :-) and which was not noticed because it works
3468 on Linux.
3470 16. pcretest is supposed to handle any length of pattern and data line (as one
3471 line or as a continued sequence of lines) by extending its input buffer if
3472 necessary. This feature was broken for very long pattern lines, leading to
3473 a string of junk being passed to pcre_compile() if the pattern was longer
3474 than about 50K.
3476 17. I have done a major re-factoring of the way pcre_compile() computes the
3477 amount of memory needed for a compiled pattern. Previously, there was code
3478 that made a preliminary scan of the pattern in order to do this. That was
3479 OK when PCRE was new, but as the facilities have expanded, it has become
3480 harder and harder to keep it in step with the real compile phase, and there
3481 have been a number of bugs (see for example, 4 above). I have now found a
3482 cunning way of running the real compile function in a "fake" mode that
3483 enables it to compute how much memory it would need, while actually only
3484 ever using a few hundred bytes of working memory and without too many
3485 tests of the mode. This should make future maintenance and development
3486 easier. A side effect of this work is that the limit of 200 on the nesting
3487 depth of parentheses has been removed (though this was never a serious
3488 limitation, I suspect). However, there is a downside: pcre_compile() now
3489 runs more slowly than before (30% or more, depending on the pattern). I
3490 hope this isn't a big issue. There is no effect on runtime performance.
3492 18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
3493 newline (only possible for the last line of a file) and it was a
3494 pattern that set a locale (followed by /Lsomething), pcretest crashed.
3496 19. Added additional timing features to pcretest. (1) The -tm option now times
3497 matching only, not compiling. (2) Both -t and -tm can be followed, as a
3498 separate command line item, by a number that specifies the number of
3499 repeats to use when timing. The default is 50000; this gives better
3500 precision, but takes uncomfortably long for very large patterns.
3502 20. Extended pcre_study() to be more clever in cases where a branch of a
3503 subpattern has no definite first character. For example, (a*|b*)[cd] would
3504 previously give no result from pcre_study(). Now it recognizes that the
3505 first character must be a, b, c, or d.
3507 21. There was an incorrect error "recursive call could loop indefinitely" if
3508 a subpattern (or the entire pattern) that was being tested for matching an
3509 empty string contained only one non-empty item after a nested subpattern.
3510 For example, the pattern (?>\x{100}*)\d(?R) provoked this error
3511 incorrectly, because the \d was being skipped in the check.
3513 22. The pcretest program now has a new pattern option /B and a command line
3514 option -b, which is equivalent to adding /B to every pattern. This causes
3515 it to show the compiled bytecode, without the additional information that
3516 -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
3517 is the same as /B/I).
3519 23. A new optimization is now able automatically to treat some sequences such
3520 as a*b as a*+b. More specifically, if something simple (such as a character
3521 or a simple class like \d) has an unlimited quantifier, and is followed by
3522 something that cannot possibly match the quantified thing, the quantifier
3523 is automatically "possessified".
3525 24. A recursive reference to a subpattern whose number was greater than 39
3526 went wrong under certain circumstances in UTF-8 mode. This bug could also
3527 have affected the operation of pcre_study().
3529 25. Realized that a little bit of performance could be had by replacing
3530 (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
3532 26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
3534 27. Possessive quantifiers such as a++ were previously implemented by turning
3535 them into atomic groups such as ($>a+). Now they have their own opcodes,
3536 which improves performance. This includes the automatically created ones
3537 from 23 above.
3539 28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
3540 lookahead was broken if it was not anchored. PCRE was mistakenly expecting
3541 the first matched character to be a colon. This applied both to named and
3542 numbered groups.
3544 29. The ucpinternal.h header file was missing its idempotency #ifdef.
3546 30. I was sent a "project" file called libpcre.a.dev which I understand makes
3547 building PCRE on Windows easier, so I have included it in the distribution.
3549 31. There is now a check in pcretest against a ridiculously large number being
3550 returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
3551 loop, the loop is abandoned.
3553 32. Forward references to subpatterns in conditions such as (?(2)...) where
3554 subpattern 2 is defined later cause pcre_compile() to search forwards in
3555 the pattern for the relevant set of parentheses. This search went wrong
3556 when there were unescaped parentheses in a character class, parentheses
3557 escaped with \Q...\E, or parentheses in a #-comment in /x mode.
3559 33. "Subroutine" calls and backreferences were previously restricted to
3560 referencing subpatterns earlier in the regex. This restriction has now
3561 been removed.
3563 34. Added a number of extra features that are going to be in Perl 5.10. On the
3564 whole, these are just syntactic alternatives for features that PCRE had
3565 previously implemented using the Python syntax or my own invention. The
3566 other formats are all retained for compatibility.
3568 (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
3569 as (?P<name>...). The new forms, as well as being in Perl 5.10, are
3570 also .NET compatible.
3572 (b) A recursion or subroutine call to a named group can now be defined as
3573 (?&name) as well as (?P>name).
3575 (c) A backreference to a named group can now be defined as \k<name> or
3576 \k'name' as well as (?P=name). The new forms, as well as being in Perl
3577 5.10, are also .NET compatible.
3579 (d) A conditional reference to a named group can now use the syntax
3580 (?(<name>) or (?('name') as well as (?(name).
3582 (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
3583 groups (named and numbered) that are never evaluated inline, but can be
3584 called as "subroutines" from elsewhere. In effect, the DEFINE condition
3585 is always false. There may be only one alternative in such a group.
3587 (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
3588 as the simple (?(R). The condition is true only if the most recent
3589 recursion is that of the given number or name. It does not search out
3590 through the entire recursion stack.
3592 (g) The escape \gN or \g{N} has been added, where N is a positive or
3593 negative number, specifying an absolute or relative reference.
3595 35. Tidied to get rid of some further signed/unsigned compiler warnings and
3596 some "unreachable code" warnings.
3598 36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
3599 things, this adds five new scripts.
3601 37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
3602 There were also incompatibilities regarding the handling of \Q..\E inside
3603 character classes, for example with patterns like [\Qa\E-\Qz\E] where the
3604 hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
3606 38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
3607 matches an empty string, and forcibly breaks the loop. There were bugs in
3608 this code in non-simple cases. For a pattern such as ^(a()*)* matched
3609 against aaaa the result was just "a" rather than "aaaa", for example. Two
3610 separate and independent bugs (that affected different cases) have been
3611 fixed.
3613 39. Refactored the code to abolish the use of different opcodes for small
3614 capturing bracket numbers. This is a tidy that I avoided doing when I
3615 removed the limit on the number of capturing brackets for 3.5 back in 2001.
3616 The new approach is not only tidier, it makes it possible to reduce the
3617 memory needed to fix the previous bug (38).
3619 40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
3620 sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
3621 processing dot, circumflex, or dollar metacharacters, or #-comments in /x
3622 mode.
3624 41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
3625 report.
3627 42. Applied patch, originally from Ari Pollak, modified by Google, to allow
3628 copy construction and assignment in the C++ wrapper.
3630 43. Updated pcregrep to support "--newline=any". In the process, I fixed a
3631 couple of bugs that could have given wrong results in the "--newline=crlf"
3632 case.
3634 44. Added a number of casts and did some reorganization of signed/unsigned int
3635 variables following suggestions from Dair Grant. Also renamed the variable
3636 "this" as "item" because it is a C++ keyword.
3638 45. Arranged for dftables to add
3640 #include "pcre_internal.h"
3642 to pcre_chartables.c because without it, gcc 4.x may remove the array
3643 definition from the final binary if PCRE is built into a static library and
3644 dead code stripping is activated.
3646 46. For an unanchored pattern, if a match attempt fails at the start of a
3647 newline sequence, and the newline setting is CRLF or ANY, and the next two
3648 characters are CRLF, advance by two characters instead of one.
3651 Version 6.7 04-Jul-06
3652 ---------------------
3654 1. In order to handle tests when input lines are enormously long, pcretest has
3655 been re-factored so that it automatically extends its buffers when
3656 necessary. The code is crude, but this _is_ just a test program. The
3657 default size has been increased from 32K to 50K.
3659 2. The code in pcre_study() was using the value of the re argument before
3660 testing it for NULL. (Of course, in any sensible call of the function, it
3661 won't be NULL.)
3663 3. The memmove() emulation function in pcre_internal.h, which is used on
3664 systems that lack both memmove() and bcopy() - that is, hardly ever -
3665 was missing a "static" storage class specifier.
3667 4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
3668 containing an extended class (one that cannot be represented by a bitmap
3669 because it contains high-valued characters or Unicode property items, e.g.
3670 [\pZ]). Almost always one would set UTF-8 mode when processing such a
3671 pattern, but PCRE should not loop if you do not (it no longer does).
3672 [Detail: two cases were found: (a) a repeated subpattern containing an
3673 extended class; (b) a recursive reference to a subpattern that followed a
3674 previous extended class. It wasn't skipping over the extended class
3675 correctly when UTF-8 mode was not set.]
3677 5. A negated single-character class was not being recognized as fixed-length
3678 in lookbehind assertions such as (?<=[^f]), leading to an incorrect
3679 compile error "lookbehind assertion is not fixed length".
3681 6. The RunPerlTest auxiliary script was showing an unexpected difference
3682 between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
3683 write a Perl script that can interpret lines of an input file either as
3684 byte characters or as UTF-8, which is what "perltest" was being required to
3685 do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
3686 can't do is switch easily at run time between having the "use utf8;" pragma
3687 or not. In the end, I fudged it by using the RunPerlTest script to insert
3688 "use utf8;" explicitly for the UTF-8 tests.
3690 7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
3691 the end of the subject string, contrary to the documentation and to what
3692 Perl does. This was true of both matching functions. Now it matches only at
3693 the start of the subject and immediately after *internal* newlines.
3695 8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
3696 a pointer to an int instead of a pointer to an unsigned long int. This
3697 caused problems on 64-bit systems.
3699 9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
3700 instance of the 'standard' template library not being so standard".
3702 10. There was no check on the number of named subpatterns nor the maximum
3703 length of a subpattern name. The product of these values is used to compute
3704 the size of the memory block for a compiled pattern. By supplying a very
3705 long subpattern name and a large number of named subpatterns, the size
3706 computation could be caused to overflow. This is now prevented by limiting
3707 the length of names to 32 characters, and the number of named subpatterns
3708 to 10,000.
3710 11. Subpatterns that are repeated with specific counts have to be replicated in
3711 the compiled pattern. The size of memory for this was computed from the
3712 length of the subpattern and the repeat count. The latter is limited to
3713 65535, but there was no limit on the former, meaning that integer overflow
3714 could in principle occur. The compiled length of a repeated subpattern is
3715 now limited to 30,000 bytes in order to prevent this.
3717 12. Added the optional facility to have named substrings with the same name.
3719 13. Added the ability to use a named substring as a condition, using the
3720 Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
3721 are numbers (not recommended). Forward references are permitted.
3723 14. Added forward references in named backreferences (if you see what I mean).
3725 15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
3726 pattern could run off the end of the subject. For example, the pattern
3727 "(?s)(.{1,5})"8 did this with the subject "ab".
3729 16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
3730 PCRE_CASELESS was set when matching characters that were quantified with ?
3731 or *.
3733 17. A character class other than a single negated character that had a minimum
3734 but no maximum quantifier - for example [ab]{6,} - was not handled
3735 correctly by pce_dfa_exec(). It would match only one character.
3737 18. A valid (though odd) pattern that looked like a POSIX character
3738 class but used an invalid character after [ (for example [[,abc,]]) caused
3739 pcre_compile() to give the error "Failed: internal error: code overflow" or
3740 in some cases to crash with a glibc free() error. This could even happen if
3741 the pattern terminated after [[ but there just happened to be a sequence of
3742 letters, a binary zero, and a closing ] in the memory that followed.
3744 19. Perl's treatment of octal escapes in the range \400 to \777 has changed
3745 over the years. Originally (before any Unicode support), just the bottom 8
3746 bits were taken. Thus, for example, \500 really meant \100. Nowadays the
3747 output from "man perlunicode" includes this:
3749 The regular expression compiler produces polymorphic opcodes. That
3750 is, the pattern adapts to the data and automatically switches to
3751 the Unicode character scheme when presented with Unicode data--or
3752 instead uses a traditional byte scheme when presented with byte
3753 data.
3755 Sadly, a wide octal escape does not cause a switch, and in a string with
3756 no other multibyte characters, these octal escapes are treated as before.
3757 Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern
3758 /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
3759 Unicode string.
3761 I have not perpetrated such confusion in PCRE. Up till now, it took just
3762 the bottom 8 bits, as in old Perl. I have now made octal escapes with
3763 values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
3764 translate to the appropriate multibyte character.
3766 29. Applied some refactoring to reduce the number of warnings from Microsoft
3767 and Borland compilers. This has included removing the fudge introduced
3768 seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
3769 a warning about an unused variable.
3771 21. PCRE has not included VT (character 0x0b) in the set of whitespace
3772 characters since release 4.0, because Perl (from release 5.004) does not.
3773 [Or at least, is documented not to: some releases seem to be in conflict
3774 with the documentation.] However, when a pattern was studied with
3775 pcre_study() and all its branches started with \s, PCRE still included VT
3776 as a possible starting character. Of course, this did no harm; it just
3777 caused an unnecessary match attempt.
3779 22. Removed a now-redundant internal flag bit that recorded the fact that case
3780 dependency changed within the pattern. This was once needed for "required
3781 byte" processing, but is no longer used. This recovers a now-scarce options
3782 bit. Also moved the least significant internal flag bit to the most-
3783 significant bit of the word, which was not previously used (hangover from
3784 the days when it was an int rather than a uint) to free up another bit for
3785 the future.
3787 23. Added support for CRLF line endings as well as CR and LF. As well as the
3788 default being selectable at build time, it can now be changed at runtime
3789 via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
3790 specify that it is scanning data with non-default line endings.
3792 24. Changed the definition of CXXLINK to make it agree with the definition of
3793 LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
3795 25. Applied Ian Taylor's patches to avoid using another stack frame for tail
3796 recursions. This makes a big different to stack usage for some patterns.
3798 26. If a subpattern containing a named recursion or subroutine reference such
3799 as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
3800 the space required for the compiled pattern went wrong and gave too small a
3801 value. Depending on the environment, this could lead to "Failed: internal
3802 error: code overflow at offset 49" or "glibc detected double free or
3803 corruption" errors.
3805 27. Applied patches from Google (a) to support the new newline modes and (b) to
3806 advance over multibyte UTF-8 characters in GlobalReplace.
3808 28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
3809 difference for some implementation of PCRE in some Windows version.
3811 29. Added some extra testing facilities to pcretest:
3813 \q<number> in a data line sets the "match limit" value
3814 \Q<number> in a data line sets the "match recursion limt" value
3815 -S <number> sets the stack size, where <number> is in megabytes
3817 The -S option isn't available for Windows.
3820 Version 6.6 06-Feb-06
3821 ---------------------
3823 1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
3824 in pcreposix.h. I have copied the definition from pcre.h.
3826 2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
3827 because pcre.h is no longer a built file.
3829 3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
3830 not normally included in the compiled code.
3833 Version 6.5 01-Feb-06
3834 ---------------------
3836 1. When using the partial match feature with pcre_dfa_exec(), it was not
3837 anchoring the second and subsequent partial matches at the new starting
3838 point. This could lead to incorrect results. For example, with the pattern
3839 /1234/, partially matching against "123" and then "a4" gave a match.
3841 2. Changes to pcregrep:
3843 (a) All non-match returns from pcre_exec() were being treated as failures
3844 to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
3845 error message is output. Some extra information is given for the
3847 probably the only errors that are likely to be caused by users (by
3848 specifying a regex that has nested indefinite repeats, for instance).
3849 If there are more than 20 of these errors, pcregrep is abandoned.
3851 (b) A binary zero was treated as data while matching, but terminated the
3852 output line if it was written out. This has been fixed: binary zeroes
3853 are now no different to any other data bytes.
3855 (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
3856 used to set a locale for matching. The --locale=xxxx long option has
3857 been added (no short equivalent) to specify a locale explicitly on the
3858 pcregrep command, overriding the environment variables.
3860 (d) When -B was used with -n, some line numbers in the output were one less
3861 than they should have been.
3863 (e) Added the -o (--only-matching) option.
3865 (f) If -A or -C was used with -c (count only), some lines of context were
3866 accidentally printed for the final match.
3868 (g) Added the -H (--with-filename) option.
3870 (h) The combination of options -rh failed to suppress file names for files
3871 that were found from directory arguments.
3873 (i) Added the -D (--devices) and -d (--directories) options.
3875 (j) Added the -F (--fixed-strings) option.
3877 (k) Allow "-" to be used as a file name for -f as well as for a data file.
3879 (l) Added the --colo(u)r option.
3881 (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
3882 is not present by default.
3884 3. A nasty bug was discovered in the handling of recursive patterns, that is,
3885 items such as (?R) or (?1), when the recursion could match a number of
3886 alternatives. If it matched one of the alternatives, but subsequently,
3887 outside the recursion, there was a failure, the code tried to back up into
3888 the recursion. However, because of the way PCRE is implemented, this is not
3889 possible, and the result was an incorrect result from the match.
3891 In order to prevent this happening, the specification of recursion has
3892 been changed so that all such subpatterns are automatically treated as
3893 atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
3895 4. I had overlooked the fact that, in some locales, there are characters for
3896 which isalpha() is true but neither isupper() nor islower() are true. In
3897 the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
3898 and ordfeminine) are like this. This affected the treatment of \w and \W
3899 when they appeared in character classes, but not when they appeared outside
3900 a character class. The bit map for "word" characters is now created
3901 separately from the results of isalnum() instead of just taking it from the
3902 upper, lower, and digit maps. (Plus the underscore character, of course.)
3904 5. The above bug also affected the handling of POSIX character classes such as
3905 [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
3906 permanent tables. Instead, the bit maps for such a class were previously
3907 created as the appropriate unions of the upper, lower, and digit bitmaps.
3908 Now they are created by subtraction from the [[:word:]] class, which has
3909 its own bitmap.
3911 6. The [[:blank:]] character class matches horizontal, but not vertical space.
3912 It is created by subtracting the vertical space characters (\x09, \x0a,
3913 \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
3914 subtraction was done in the overall bitmap for a character class, meaning
3915 that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
3916 be recognized. This bug has been fixed.
3918 7. Patches from the folks at Google:
3920 (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
3921 real life, but is still worth protecting against".
3923 (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
3924 regular expressions".
3926 (c) pcre_scanner.cc: avoid use of std::count() because not all systems
3927 have it.
3929 (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
3930 "configure" and the latter not, in order to fix a problem somebody had
3931 with compiling the Arg class on HP-UX.
3933 (e) Improve the error-handling of the C++ wrapper a little bit.
3935 (f) New tests for checking recursion limiting.
3937 8. The pcre_memmove() function, which is used only if the environment does not
3938 have a standard memmove() function (and is therefore rarely compiled),
3939 contained two bugs: (a) use of int instead of size_t, and (b) it was not
3940 returning a result (though PCRE never actually uses the result).
3942 9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
3943 large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
3944 returned instead of calling malloc() with an overflowing number that would
3945 most likely cause subsequent chaos.
3947 10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
3949 11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
3950 with this option is matched, the nmatch and pmatch options of regexec() are
3951 ignored.
3953 12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
3954 provided in case anyone wants to the the POSIX interface with UTF-8
3955 strings.
3957 13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
3958 C++ linking (needed for some HP-UX environments).
3960 14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
3961 (unused parameter) and in the pcre_printint() function (omitted "default"
3962 switch label when the default is to do nothing).
3964 15. Added some code to make it possible, when PCRE is compiled as a C++
3965 library, to replace subject pointers for pcre_exec() with a smart pointer
3966 class, thus making it possible to process discontinuous strings.
3968 16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
3969 much the same function. They were added by different people who were trying
3970 to make PCRE easy to compile on non-Unix systems. It has been suggested
3971 that PCRE_EXPORT be abolished now that there is more automatic apparatus
3972 for compiling on Windows systems. I have therefore replaced it with
3973 PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
3974 defaults to "extern" for C or "extern C" for C++, which works fine on
3975 Unix-like systems. It is now possible to override the value of PCRE_DATA_
3976 SCOPE with something explicit in config.h. In addition:
3978 (a) pcreposix.h still had just "extern" instead of either of these macros;
3979 I have replaced it with PCRE_DATA_SCOPE.
3981 (b) Functions such as _pcre_xclass(), which are internal to the library,
3982 but external in the C sense, all had PCRE_EXPORT in their definitions.
3983 This is apparently wrong for the Windows case, so I have removed it.
3984 (It makes no difference on Unix-like systems.)
3986 17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
3987 of recursive calls to match(). This is different to MATCH_LIMIT because
3988 that limits the total number of calls to match(), not all of which increase
3989 the depth of recursion. Limiting the recursion depth limits the amount of
3990 stack (or heap if NO_RECURSE is set) that is used. The default can be set
3991 when PCRE is compiled, and changed at run time. A patch from Google adds
3992 this functionality to the C++ interface.
3994 18. Changes to the handling of Unicode character properties:
3996 (a) Updated the table to Unicode 4.1.0.
3998 (b) Recognize characters that are not in the table as "Cn" (undefined).
4000 (c) I revised the way the table is implemented to a much improved format
4001 which includes recognition of ranges. It now supports the ranges that
4002 are defined in UnicodeData.txt, and it also amalgamates other
4003 characters into ranges. This has reduced the number of entries in the
4004 table from around 16,000 to around 3,000, thus reducing its size
4005 considerably. I realized I did not need to use a tree structure after
4006 all - a binary chop search is just as efficient. Having reduced the
4007 number of entries, I extended their size from 6 bytes to 8 bytes to
4008 allow for more data.
4010 (d) Added support for Unicode script names via properties such as \p{Han}.
4012 19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
4013 matching that character.
4015 20. When matching a repeated Unicode property with a minimum greater than zero,
4016 (for example \pL{2,}), PCRE could look past the end of the subject if it
4017 reached it while seeking the minimum number of characters. This could
4018 happen only if some of the characters were more than one byte long, because
4019 there is a check for at least the minimum number of bytes.
4021 21. Refactored the implementation of \p and \P so as to be more general, to
4022 allow for more different types of property in future. This has changed the
4023 compiled form incompatibly. Anybody with saved compiled patterns that use
4024 \p or \P will have to recompile them.
4026 22. Added "Any" and "L&" to the supported property types.
4028 23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
4029 but give a compile time error if the value is greater than 0xff.
4031 24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
4032 accidentally not being installed or uninstalled.
4034 25. The pcre.h file was built from pcre.h.in, but the only changes that were
4035 made were to insert the current release number. This seemed silly, because
4036 it made things harder for people building PCRE on systems that don't run
4037 "configure". I have turned pcre.h into a distributed file, no longer built
4038 by "configure", with the version identification directly included. There is
4039 no longer a pcre.h.in file.
4041 However, this change necessitated a change to the pcre-config script as
4042 well. It is built from pcre-config.in, and one of the substitutions was the
4043 release number. I have updated configure.ac so that ./configure now finds
4044 the release number by grepping pcre.h.
4046 26. Added the ability to run the tests under valgrind.
4049 Version 6.4 05-Sep-05
4050 ---------------------
4052 1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
4053 "--" to be printed when multiple files were scanned, even when none of the
4054 -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
4055 consider it to be a bug, and have restored the previous behaviour.
4057 2. A couple of code tidies to get rid of compiler warnings.
4059 3. The pcretest program used to cheat by referring to symbols in the library
4060 whose names begin with _pcre_. These are internal symbols that are not
4061 really supposed to be visible externally, and in some environments it is
4062 possible to suppress them. The cheating is now confined to including
4063 certain files from the library's source, which is a bit cleaner.
4065 4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
4066 file's purpose clearer.
4068 5. Reorganized pcre_ucp_findchar().
4071 Version 6.3 15-Aug-05
4072 ---------------------
4074 1. The file libpcre.pc.in did not have general read permission in the tarball.
4076 2. There were some problems when building without C++ support:
4078 (a) If C++ support was not built, "make install" and "make test" still
4079 tried to test it.
4081 (b) There were problems when the value of CXX was explicitly set. Some
4082 changes have been made to try to fix these, and ...
4084 (c) --disable-cpp can now be used to explicitly disable C++ support.
4086 (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
4087 backslash in a target when C++ was disabled. This confuses some
4088 versions of "make", apparently. Using an intermediate variable solves
4089 this. (Same for CPP_LOBJ.)
4091 3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
4092 (non-Windows) now includes $(CFLAGS) because these flags are sometimes
4093 necessary on certain architectures.
4095 4. Added a setting of -export-symbols-regex to the link command to remove
4096 those symbols that are exported in the C sense, but actually are local
4097 within the library, and not documented. Their names all begin with
4098 "_pcre_". This is not a perfect job, because (a) we have to except some
4099 symbols that pcretest ("illegally") uses, and (b) the facility isn't always
4100 available (and never for static libraries). I have made a note to try to
4101 find a way round (a) in the future.
4104 Version 6.2 01-Aug-05
4105 ---------------------
4107 1. There was no test for integer overflow of quantifier values. A construction
4108 such as {1111111111111111} would give undefined results. What is worse, if
4109 a minimum quantifier for a parenthesized subpattern overflowed and became
4110 negative, the calculation of the memory size went wrong. This could have
4111 led to memory overwriting.
4113 2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
4115 3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
4116 operating environments where this matters.
4118 4. Applied Giuseppe Maxia's patch to add additional features for controlling
4119 PCRE options from within the C++ wrapper.
4121 5. Named capturing subpatterns were not being correctly counted when a pattern
4122 was compiled. This caused two problems: (a) If there were more than 100
4123 such subpatterns, the calculation of the memory needed for the whole
4124 compiled pattern went wrong, leading to an overflow error. (b) Numerical
4125 back references of the form \12, where the number was greater than 9, were
4126 not recognized as back references, even though there were sufficient
4127 previous subpatterns.
4129 6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
4130 versions of gcc, e.g. 2.95.4.
4133 Version 6.1 21-Jun-05
4134 ---------------------
4136 1. There was one reference to the variable "posix" in pcretest.c that was not
4137 surrounded by "#if !defined NOPOSIX".
4139 2. Make it possible to compile pcretest without DFA support, UTF8 support, or
4140 the cross-check on the old pcre_info() function, for the benefit of the
4141 cut-down version of PCRE that is currently imported into Exim.
4143 3. A (silly) pattern starting with (?i)(?-i) caused an internal space
4144 allocation error. I've done the easy fix, which wastes 2 bytes for sensible
4145 patterns that start (?i) but I don't think that matters. The use of (?i) is
4146 just an example; this all applies to the other options as well.
4148 4. Since libtool seems to echo the compile commands it is issuing, the output
4149 from "make" can be reduced a bit by putting "@" in front of each libtool
4150 compile command.
4152 5. Patch from the folks at Google for configure.in to be a bit more thorough
4153 in checking for a suitable C++ installation before trying to compile the
4154 C++ stuff. This should fix a reported problem when a compiler was present,
4155 but no suitable headers.
4157 6. The man pages all had just "PCRE" as their title. I have changed them to
4158 be the relevant file name. I have also arranged that these names are
4159 retained in the file doc/pcre.txt, which is a concatenation in text format
4160 of all the man pages except the little individual ones for each function.
4162 7. The NON-UNIX-USE file had not been updated for the different set of source
4163 files that come with release 6. I also added a few comments about the C++
4164 wrapper.
4167 Version 6.0 07-Jun-05
4168 ---------------------
4170 1. Some minor internal re-organization to help with my DFA experiments.
4172 2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
4173 didn't matter for the library itself when fully configured, but did matter
4174 when compiling without UCP support, or within Exim, where the ucp files are
4175 not imported.
4177 3. Refactoring of the library code to split up the various functions into
4178 different source modules. The addition of the new DFA matching code (see
4179 below) to a single monolithic source would have made it really too
4180 unwieldy, quite apart from causing all the code to be include in a
4181 statically linked application, when only some functions are used. This is
4182 relevant even without the DFA addition now that patterns can be compiled in
4183 one application and matched in another.
4185 The downside of splitting up is that there have to be some external
4186 functions and data tables that are used internally in different modules of
4187 the library but which are not part of the API. These have all had their
4188 names changed to start with "_pcre_" so that they are unlikely to clash
4189 with other external names.
4191 4. Added an alternate matching function, pcre_dfa_exec(), which matches using
4192 a different (DFA) algorithm. Although it is slower than the original
4193 function, it does have some advantages for certain types of matching
4194 problem.
4196 5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
4197 including restarting after a partial match.
4199 6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
4200 defined when compiling for Windows was sent to me. I have put it into the
4201 code, though I have no means of testing or verifying it.
4203 7. Added the pcre_refcount() auxiliary function.
4205 8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
4206 match before or at the first newline in the subject string. In pcretest,
4207 the /f option on a pattern can be used to set this.
4209 9. A repeated \w when used in UTF-8 mode with characters greater than 256
4210 would behave wrongly. This has been present in PCRE since release 4.0.
4212 10. A number of changes to the pcregrep command:
4214 (a) Refactored how -x works; insert ^(...)$ instead of setting
4215 PCRE_ANCHORED and checking the length, in preparation for adding
4216 something similar for -w.
4218 (b) Added the -w (match as a word) option.
4220 (c) Refactored the way lines are read and buffered so as to have more
4221 than one at a time available.
4223 (d) Implemented a pcregrep test script.
4225 (e) Added the -M (multiline match) option. This allows patterns to match
4226 over several lines of the subject. The buffering ensures that at least
4227 8K, or the rest of the document (whichever is the shorter) is available
4228 for matching (and similarly the previous 8K for lookbehind assertions).
4230 (f) Changed the --help output so that it now says
4232 -w, --word-regex(p)
4234 instead of two lines, one with "regex" and the other with "regexp"
4235 because that confused at least one person since the short forms are the
4236 same. (This required a bit of code, as the output is generated
4237 automatically from a table. It wasn't just a text change.)
4239 (g) -- can be used to terminate pcregrep options if the next thing isn't an
4240 option but starts with a hyphen. Could be a pattern or a path name
4241 starting with a hyphen, for instance.
4243 (h) "-" can be given as a file name to represent stdin.
4245 (i) When file names are being printed, "(standard input)" is used for
4246 the standard input, for compatibility with GNU grep. Previously
4247 "<stdin>" was used.
4249 (j) The option --label=xxx can be used to supply a name to be used for
4250 stdin when file names are being printed. There is no short form.
4252 (k) Re-factored the options decoding logic because we are going to add
4253 two more options that take data. Such options can now be given in four
4254 different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
4256 (l) Added the -A, -B, and -C options for requesting that lines of context
4257 around matches be printed.
4259 (m) Added the -L option to print the names of files that do not contain
4260 any matching lines, that is, the complement of -l.
4262 (n) The return code is 2 if any file cannot be opened, but pcregrep does
4263 continue to scan other files.
4265 (o) The -s option was incorrectly implemented. For compatibility with other
4266 greps, it now suppresses the error message for a non-existent or non-
4267 accessible file (but not the return code). There is a new option called
4268 -q that suppresses the output of matching lines, which was what -s was
4269 previously doing.
4271 (p) Added --include and --exclude options to specify files for inclusion
4272 and exclusion when recursing.
4274 11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
4275 Hopefully, it now does.
4277 12. Missing cast in pcre_study().
4279 13. Added an "uninstall" target to the makefile.
4281 14. Replaced "extern" in the function prototypes in Makefile.in with
4282 "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
4283 world, but is set differently for Windows.
4285 15. Added a second compiling function called pcre_compile2(). The only
4286 difference is that it has an extra argument, which is a pointer to an
4287 integer error code. When there is a compile-time failure, this is set
4288 non-zero, in addition to the error test pointer being set to point to an
4289 error message. The new argument may be NULL if no error number is required
4290 (but then you may as well call pcre_compile(), which is now just a
4291 wrapper). This facility is provided because some applications need a
4292 numeric error indication, but it has also enabled me to tidy up the way
4293 compile-time errors are handled in the POSIX wrapper.
4295 16. Added VPATH=.libs to the makefile; this should help when building with one
4296 prefix path and installing with another. (Or so I'm told by someone who
4297 knows more about this stuff than I do.)
4299 17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
4300 passes PCRE_DOTALL to the pcre_compile() function, making the "." character
4301 match everything, including newlines. This is not POSIX-compatible, but
4302 somebody wanted the feature. From pcretest it can be activated by using
4303 both the P and the s flags.
4305 18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
4307 19. libpcre.pc was being incorrectly installed as executable.
4309 20. A couple of places in pcretest check for end-of-line by looking for '\n';
4310 it now also looks for '\r' so that it will work unmodified on Windows.
4312 21. Added Google's contributed C++ wrapper to the distribution.
4314 22. Added some untidy missing memory free() calls in pcretest, to keep
4315 Electric Fence happy when testing.
4319 Version 5.0 13-Sep-04
4320 ---------------------
4322 1. Internal change: literal characters are no longer packed up into items
4323 containing multiple characters in a single byte-string. Each character
4324 is now matched using a separate opcode. However, there may be more than one
4325 byte in the character in UTF-8 mode.
4327 2. The pcre_callout_block structure has two new fields: pattern_position and
4328 next_item_length. These contain the offset in the pattern to the next match
4329 item, and its length, respectively.
4331 3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
4332 insertion of callouts before each pattern item. Added the /C option to
4333 pcretest to make use of this.
4335 4. On the advice of a Windows user, the lines
4337 #if defined(_WIN32) || defined(WIN32)
4338 _setmode( _fileno( stdout ), 0x8000 );
4339 #endif /* defined(_WIN32) || defined(WIN32) */
4341 have been added to the source of pcretest. This apparently does useful
4342 magic in relation to line terminators.
4344 5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
4345 for the benefit of those environments where the "b" makes a difference.
4347 6. The icc compiler has the same options as gcc, but "configure" doesn't seem
4348 to know about it. I have put a hack into configure.in that adds in code
4349 to set GCC=yes if CC=icc. This seems to end up at a point in the
4350 generated configure script that is early enough to affect the setting of
4351 compiler options, which is what is needed, but I have no means of testing
4352 whether it really works. (The user who reported this had patched the
4353 generated configure script, which of course I cannot do.)
4355 LATER: After change 22 below (new libtool files), the configure script
4356 seems to know about icc (and also ecc). Therefore, I have commented out
4357 this hack in configure.in.
4359 7. Added support for pkg-config (2 patches were sent in).
4361 8. Negated POSIX character classes that used a combination of internal tables
4362 were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
4363 [[:^ascii]]. Typically, they would match almost any characters. The other
4364 POSIX classes were not broken in this way.
4366 9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
4367 to find the match, as PCRE was deluded into thinking that the match had to
4368 start at the start point or following a newline. The same bug applied to
4369 patterns with negative forward assertions or any backward assertions
4370 preceding ".*" at the start, unless the pattern required a fixed first
4371 character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
4373 10. In UTF-8 mode, when moving forwards in the subject after a failed match
4374 starting at the last subject character, bytes beyond the end of the subject
4375 string were read.
4377 11. Renamed the variable "class" as "classbits" to make life easier for C++
4378 users. (Previously there was a macro definition, but it apparently wasn't
4379 enough.)
4381 12. Added the new field "tables" to the extra data so that tables can be passed
4382 in at exec time, or the internal tables can be re-selected. This allows
4383 a compiled regex to be saved and re-used at a later time by a different
4384 program that might have everything at different addresses.
4386 13. Modified the pcre-config script so that, when run on Solaris, it shows a
4387 -R library as well as a -L library.
4389 14. The debugging options of pcretest (-d on the command line or D on a
4390 pattern) showed incorrect output for anything following an extended class
4391 that contained multibyte characters and which was followed by a quantifier.
4393 15. Added optional support for general category Unicode character properties
4394 via the \p, \P, and \X escapes. Unicode property support implies UTF-8
4395 support. It adds about 90K to the size of the library. The meanings of the
4396 inbuilt class escapes such as \d and \s have NOT been changed.
4398 16. Updated pcredemo.c to include calls to free() to release the memory for the
4399 compiled pattern.
4401 17. The generated file chartables.c was being created in the source directory
4402 instead of in the building directory. This caused the build to fail if the
4403 source directory was different from the building directory, and was
4404 read-only.
4406 18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
4407 file. No doubt somebody will tell me if they don't make sense... Also added
4408 Dan Mooney's comments about building on OpenVMS.
4410 19. Added support for partial matching via the PCRE_PARTIAL option for
4411 pcre_exec() and the \P data escape in pcretest.
4413 20. Extended pcretest with 3 new pattern features:
4415 (i) A pattern option of the form ">rest-of-line" causes pcretest to
4416 write the compiled pattern to the file whose name is "rest-of-line".
4417 This is a straight binary dump of the data, with the saved pointer to
4418 the character tables forced to be NULL. The study data, if any, is
4419 written too. After writing, pcretest reads a new pattern.
4421 (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
4422 compiled pattern from the given file. There must not be any
4423 occurrences of "<" in the file name (pretty unlikely); if there are,
4424 pcretest will instead treat the initial "<" as a pattern delimiter.
4425 After reading in the pattern, pcretest goes on to read data lines as
4426 usual.
4428 (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
4429 and 16-bit fields in a compiled pattern, to simulate a pattern that
4430 was compiled on a host of opposite endianness.
4432 21. The pcre-exec() function can now cope with patterns that were compiled on
4433 hosts of opposite endianness, with this restriction:
4435 As for any compiled expression that is saved and used later, the tables
4436 pointer field cannot be preserved; the extra_data field in the arguments
4437 to pcre_exec() should be used to pass in a tables address if a value
4438 other than the default internal tables were used at compile time.
4440 22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
4441 now diagnosed as an error. Previously, most of the time, a negative number
4442 would have been treated as zero, but if in addition "ovector" was passed as
4443 NULL, a crash could occur.
4445 23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
4446 new versions from the libtool 1.5 distribution (the last one is a copy of
4447 a file called libtool.m4). This seems to have fixed the need to patch
4448 "configure" to support Darwin 1.3 (which I used to do). However, I still
4449 had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
4450 workstation).
4452 24. Changed the PCRE licence to be the more standard "BSD" licence.
4455 Version 4.5 01-Dec-03
4456 ---------------------
4458 1. There has been some re-arrangement of the code for the match() function so
4459 that it can be compiled in a version that does not call itself recursively.
4460 Instead, it keeps those local variables that need separate instances for
4461 each "recursion" in a frame on the heap, and gets/frees frames whenever it
4462 needs to "recurse". Keeping track of where control must go is done by means
4463 of setjmp/longjmp. The whole thing is implemented by a set of macros that
4464 hide most of the details from the main code, and operates only if
4465 NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
4466 "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
4467 operating.
4469 To make it easier for callers to provide specially tailored get/free
4470 functions for this usage, two new functions, pcre_stack_malloc, and
4471 pcre_stack_free, are used. They are always called in strict stacking order,
4472 and the size of block requested is always the same.
4474 The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
4475 PCRE has been compiled to use the stack or the heap for recursion. The
4476 -C option of pcretest uses this to show which version is compiled.
4478 A new data escape \S, is added to pcretest; it causes the amounts of store
4479 obtained and freed by both kinds of malloc/free at match time to be added
4480 to the output.
4482 2. Changed the locale test to use "fr_FR" instead of "fr" because that's
4483 what's available on my current Linux desktop machine.
4485 3. When matching a UTF-8 string, the test for a valid string at the start has
4486 been extended. If start_offset is not zero, PCRE now checks that it points
4487 to a byte that is the start of a UTF-8 character. If not, it returns
4488 PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
4489 this is necessary because there may be backward assertions in the pattern.
4490 When matching the same subject several times, it may save resources to use
4491 PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
4493 4. The code for checking the validity of UTF-8 strings has been tightened so
4494 that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
4495 containing "overlong sequences".
4497 5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
4498 I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
4499 should have been "&", but it just so happened that all the cases this let
4500 through by mistake were picked up later in the function.
4502 6. I had used a variable called "isblank" - this is a C99 function, causing
4503 some compilers to warn. To avoid this, I renamed it (as "blankclass").
4505 7. Cosmetic: (a) only output another newline at the end of pcretest if it is
4506 prompting; (b) run "./pcretest /dev/null" at the start of the test script
4507 so the version is shown; (c) stop "make test" echoing "./RunTest".
4509 8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
4511 9. The prototype for memmove() for systems that don't have it was using
4512 size_t, but the inclusion of the header that defines size_t was later. I've
4513 moved the #includes for the C headers earlier to avoid this.
4515 10. Added some adjustments to the code to make it easier to compiler on certain
4516 special systems:
4518 (a) Some "const" qualifiers were missing.
4519 (b) Added the macro EXPORT before all exported functions; by default this
4520 is defined to be empty.
4521 (c) Changed the dftables auxiliary program (that builds chartables.c) so
4522 that it reads its output file name as an argument instead of writing
4523 to the standard output and assuming this can be redirected.
4525 11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
4526 class containing characters with values greater than 255, PCRE compilation
4527 went into a loop.
4529 12. A recursive reference to a subpattern that was within another subpattern
4530 that had a minimum quantifier of zero caused PCRE to crash. For example,
4531 (x(y(?2))z)? provoked this bug with a subject that got as far as the
4532 recursion. If the recursively-called subpattern itself had a zero repeat,
4533 that was OK.
4535 13. In pcretest, the buffer for reading a data line was set at 30K, but the
4536 buffer into which it was copied (for escape processing) was still set at
4537 1024, so long lines caused crashes.
4539 14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
4540 "internal error: code overflow...". This applied to any character class
4541 that was followed by a possessive quantifier.
4543 15. Modified the Makefile to add libpcre.la as a prerequisite for
4544 libpcreposix.la because I was told this is needed for a parallel build to
4545 work.
4547 16. If a pattern that contained .* following optional items at the start was
4548 studied, the wrong optimizing data was generated, leading to matching
4549 errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
4550 matching string must start with a or b or c. The correct conclusion for
4551 this pattern is that a match can start with any character.
4554 Version 4.4 13-Aug-03
4555 ---------------------
4557 1. In UTF-8 mode, a character class containing characters with values between
4558 127 and 255 was not handled correctly if the compiled pattern was studied.
4559 In fixing this, I have also improved the studying algorithm for such
4560 classes (slightly).
4562 2. Three internal functions had redundant arguments passed to them. Removal
4563 might give a very teeny performance improvement.
4565 3. Documentation bug: the value of the capture_top field in a callout is *one
4566 more than* the number of the hightest numbered captured substring.
4568 4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
4569 in incorrectly linking with a previously installed version. They now link
4570 explicitly with libpcre.la.
4572 5. configure.in no longer needs to recognize Cygwin specially.
4574 6. A problem in pcre.in for Windows platforms is fixed.
4576 7. If a pattern was successfully studied, and the -d (or /D) flag was given to
4577 pcretest, it used to include the size of the study block as part of its
4578 output. Unfortunately, the structure contains a field that has a different
4579 size on different hardware architectures. This meant that the tests that
4580 showed this size failed. As the block is currently always of a fixed size,
4581 this information isn't actually particularly useful in pcretest output, so
4582 I have just removed it.
4584 8. Three pre-processor statements accidentally did not start in column 1.
4585 Sadly, there are *still* compilers around that complain, even though
4586 standard C has not required this for well over a decade. Sigh.
4588 9. In pcretest, the code for checking callouts passed small integers in the
4589 callout_data field, which is a void * field. However, some picky compilers
4590 complained about the casts involved for this on 64-bit systems. Now
4591 pcretest passes the address of the small integer instead, which should get
4592 rid of the warnings.
4594 10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
4595 both compile and run time, and gives an error if an invalid UTF-8 sequence
4596 is found. There is a option for disabling this check in cases where the
4597 string is known to be correct and/or the maximum performance is wanted.
4599 11. In response to a bug report, I changed one line in Makefile.in from
4601 -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
4602 to
4603 -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
4605 to look similar to other lines, but I have no way of telling whether this
4606 is the right thing to do, as I do not use Windows. No doubt I'll get told
4607 if it's wrong...
4610 Version 4.3 21-May-03
4611 ---------------------
4613 1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
4614 Makefile.
4616 2. Some refactoring to improve the quality of the code:
4618 (i) The utf8_table... variables are now declared "const".
4620 (ii) The code for \cx, which used the "case flipping" table to upper case
4621 lower case letters, now just substracts 32. This is ASCII-specific,
4622 but the whole concept of \cx is ASCII-specific, so it seems
4623 reasonable.
4625 (iii) PCRE was using its character types table to recognize decimal and
4626 hexadecimal digits in the pattern. This is silly, because it handles
4627 only 0-9, a-f, and A-F, but the character types table is locale-
4628 specific, which means strange things might happen. A private
4629 table is now used for this - though it costs 256 bytes, a table is
4630 much faster than multiple explicit tests. Of course, the standard
4631 character types table is still used for matching digits in subject
4632 strings against \d.
4634 (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
4635 ending in _t are). So I've renamed it as ESC_tee.
4637 3. The first argument for regexec() in the POSIX wrapper should have been
4638 defined as "const".
4640 4. Changed pcretest to use malloc() for its buffers so that they can be
4641 Electric Fenced for debugging.
4643 5. There were several places in the code where, in UTF-8 mode, PCRE would try
4644 to read one or more bytes before the start of the subject string. Often this
4645 had no effect on PCRE's behaviour, but in some circumstances it could
4646 provoke a segmentation fault.
4648 6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
4649 to try to read one or more bytes before the start of the subject string.
4651 7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
4652 UTF-8 support could misbehave in various ways if the subject string
4653 contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
4654 area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
4655 back over UTF-8 characters.)
4658 Version 4.2 14-Apr-03
4659 ---------------------
4661 1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
4663 2. Changes to the building process, supplied by Ronald Landheer-Cieslak
4664 [ON_WINDOWS]: new variable, "#" on non-Windows platforms
4665 [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
4666 [WIN_PREFIX]: new variable, "cyg" for Cygwin
4667 * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
4669 Note: automatic setting of the BUILD variables is not yet working
4670 set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
4671 compile-time but not at link-time
4672 [LINK]: use for linking executables only
4673 make different versions for Windows and non-Windows
4674 [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
4675 libraries
4676 [LINK_FOR_BUILD]: new variable
4677 [OBJEXT]: use throughout
4678 [EXEEXT]: use throughout
4679 <winshared>: new target
4680 <wininstall>: new target
4681 <dftables.o>: use native compiler
4682 <dftables>: use native linker
4683 <install>: handle Windows platform correctly
4684 <clean>: ditto
4685 <check>: ditto
4686 copy DLL to top builddir before testing
4688 As part of these changes, -no-undefined was removed again. This was reported
4689 to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
4690 in any case.
4692 3. Some tidies to get rid of compiler warnings:
4694 . In the match_data structure, match_limit was an unsigned long int, whereas
4695 match_call_count was an int. I've made them both unsigned long ints.
4697 . In pcretest the fact that a const uschar * doesn't automatically cast to
4698 a void * provoked a warning.
4700 . Turning on some more compiler warnings threw up some "shadow" variables
4701 and a few more missing casts.
4703 4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
4704 option, a class that contained a single character with a value between 128
4705 and 255 (e.g. /[\xFF]/) caused PCRE to crash.
4707 5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
4708 option, a class that contained several characters, but with at least one
4709 whose value was between 128 and 255 caused PCRE to crash.
4712 Version 4.1 12-Mar-03
4713 ---------------------
4715 1. Compiling with gcc -pedantic found a couple of places where casts were
4716 needed, and a string in dftables.c that was longer than standard compilers are
4717 required to support.
4719 2. Compiling with Sun's compiler found a few more places where the code could
4720 be tidied up in order to avoid warnings.
4722 3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
4723 first of these names is deprecated in the latest Autoconf in favour of the name
4724 CC_FOR_BUILD, because "host" is typically used to mean the system on which the
4725 compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
4726 analogy I have changed it to CFLAGS_FOR_BUILD.
4728 4. Added -no-undefined to the linking command in the Makefile, because this is
4729 apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
4730 linking step for the pcreposix library.
4732 5. PCRE was failing to diagnose the case of two named groups with the same
4733 name.
4735 6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
4736 literal character that is needed in the subject for a match, and scans along to
4737 ensure that it is present before embarking on the full matching process. This
4738 saves time in cases of nested unlimited repeats that are never going to match.
4739 Problem: the scan can take a lot of time if the subject is very long (e.g.
4740 megabytes), thus penalizing straightforward matches. It is now done only if the
4741 amount of subject to be scanned is less than 1000 bytes.
4743 7. A lesser problem with the same optimization is that it was recording the
4744 first character of an anchored pattern as "needed", thus provoking a search
4745 right along the subject, even when the first match of the pattern was going to
4746 fail. The "needed" character is now not set for anchored patterns, unless it
4747 follows something in the pattern that is of non-fixed length. Thus, it still
4748 fulfils its original purpose of finding quick non-matches in cases of nested
4749 unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
4752 Version 4.0 17-Feb-03
4753 ---------------------
4755 1. If a comment in an extended regex that started immediately after a meta-item
4756 extended to the end of string, PCRE compiled incorrect data. This could lead to
4757 all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
4759 2. Moved to autoconf 2.53 and libtool 1.4.2.
4761 3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
4762 the special perltest8 script is no longer needed - all the tests can be run
4763 from a single perltest script.
4765 4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
4766 by \s. It has now been removed in PCRE. This means it isn't recognized as
4767 whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
4768 class [:space:] *does* include VT, thereby creating a mess.
4770 5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
4771 space and tab.
4773 6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
4774 its new features into the main test script, reducing the number of scripts.
4776 7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
4777 were backward compatible, and made the (?i) apply to the whole pattern, as if
4778 /i were given. Now it behaves more logically, and applies the option setting
4779 only to what follows. PCRE has been changed to follow suit. However, if it
4780 finds options settings right at the start of the pattern, it extracts them into
4781 the global options, as before. Thus, they show up in the info data.
4783 8. Added support for the \Q...\E escape sequence. Characters in between are
4784 treated as literals. This is slightly different from Perl in that $ and @ are
4785 also handled as literals inside the quotes. In Perl, they will cause variable
4786 interpolation. Note the following examples:
4788 Pattern PCRE matches Perl matches
4790 \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
4791 \Qabc\$xyz\E abc\$xyz abc\$xyz
4792 \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
4794 For compatibility with Perl, \Q...\E sequences are recognized inside character
4795 classes as well as outside them.
4797 9. Re-organized 3 code statements in pcretest to avoid "overflow in
4798 floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
4799 (size_t) cast to one statement in pcretest and one in pcreposix to avoid
4800 signed/unsigned warnings.
4802 10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
4803 option for pcretest, so I've replaced it by a simple function that does just
4804 that job.
4806 11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
4807 "pcregrep -".
4809 12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
4810 Java package. This provides some syntactic sugar for simple cases of what my
4811 documentation calls "once-only subpatterns". A pattern such as x*+ is the same
4812 as (?>x*). In other words, if what is inside (?>...) is just a single repeated
4813 item, you can use this simplified notation. Note that only makes sense with
4814 greedy quantifiers. Consequently, the use of the possessive quantifier forces
4815 greediness, whatever the setting of the PCRE_UNGREEDY option.
4817 13. A change of greediness default within a pattern was not taking effect at
4818 the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
4819 subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
4820 was abstracted outside.
4822 14. PCRE now supports the \G assertion. It is true when the current matching
4823 position is at the start point of the match. This differs from \A when the
4824 starting offset is non-zero. Used with the /g option of pcretest (or similar
4825 code), it works in the same way as it does for Perl's /g option. If all
4826 alternatives of a regex begin with \G, the expression is anchored to the start
4827 match position, and the "anchored" flag is set in the compiled expression.
4829 15. Some bugs concerning the handling of certain option changes within patterns
4830 have been fixed. These applied to options other than (?ims). For example,
4831 "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
4832 been the other way round. Some of this was related to change 7 above.
4834 16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
4835 features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
4836 and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
4837 POSIX classes only within a class (e.g. /[[:alpha:]]/).
4839 17. Added support for Perl's \C escape. This matches one byte, even in UTF8
4840 mode. Unlike ".", it always matches newline, whatever the setting of
4841 PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
4842 assertions. Perl allows it, but it doesn't (in general) work because it can't
4843 calculate the length of the lookbehind. At least, that's the case for Perl
4844 5.8.0 - I've been told they are going to document that it doesn't work in
4845 future.
4847 18. Added an error diagnosis for escapes that PCRE does not support: these are
4848 \L, \l, \N, \P, \p, \U, \u, and \X.
4850 19. Although correctly diagnosing a missing ']' in a character class, PCRE was
4851 reading past the end of the pattern in cases such as /[abcd/.
4853 20. PCRE was getting more memory than necessary for patterns with classes that
4854 contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
4856 21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
4857 compiling PCRE for use with Virtual Pascal.
4859 22. Small fix to the Makefile to make it work properly if the build is done
4860 outside the source tree.
4862 23. Added a new extension: a condition to go with recursion. If a conditional
4863 subpattern starts with (?(R) the "true" branch is used if recursion has
4864 happened, whereas the "false" branch is used only at the top level.
4866 24. When there was a very long string of literal characters (over 255 bytes
4867 without UTF support, over 250 bytes with UTF support), the computation of how
4868 much memory was required could be incorrect, leading to segfaults or other
4869 strange effects.
4871 25. PCRE was incorrectly assuming anchoring (either to start of subject or to
4872 start of line for a non-DOTALL pattern) when a pattern started with (.*) and
4873 there was a subsequent back reference to those brackets. This meant that, for
4874 example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
4875 possible to check for precisely this case. All we can do is abandon the
4876 optimization if .* occurs inside capturing brackets when there are any back
4877 references whatsoever. (See below for a better fix that came later.)
4879 26. The handling of the optimization for finding the first character of a
4880 non-anchored pattern, and for finding a character that is required later in the
4881 match were failing in some cases. This didn't break the matching; it just
4882 failed to optimize when it could. The way this is done has been re-implemented.
4884 27. Fixed typo in error message for invalid (?R item (it said "(?p").
4886 28. Added a new feature that provides some of the functionality that Perl
4887 provides with (?{...}). The facility is termed a "callout". The way it is done
4888 in PCRE is for the caller to provide an optional function, by setting
4889 pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
4890 global variable. By default it is unset, which disables all calling out. To get
4891 the function called, the regex must include (?C) at appropriate points. This
4892 is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
4893 This provides a means of identifying different callout points. When PCRE
4894 reaches such a point in the regex, if pcre_callout has been set, the external
4895 function is called. It is provided with data in a structure called
4896 pcre_callout_block, which is defined in pcre.h. If the function returns 0,
4897 matching continues; if it returns a non-zero value, the match at the current
4898 point fails. However, backtracking will occur if possible. [This was changed
4899 later and other features added - see item 49 below.]
4901 29. pcretest is upgraded to test the callout functionality. It provides a
4902 callout function that displays information. By default, it shows the start of
4903 the match and the current position in the text. There are some new data escapes
4904 to vary what happens:
4906 \C+ in addition, show current contents of captured substrings
4907 \C- do not supply a callout function
4908 \C!n return 1 when callout number n is reached
4909 \C!n!m return 1 when callout number n is reached for the mth time
4911 30. If pcregrep was called with the -l option and just a single file name, it
4912 output "<stdin>" if a match was found, instead of the file name.
4914 31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
4915 slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
4916 pcre_exec(). This saves a malloc/free per call. The default value of
4917 POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
4918 when configuring.
4920 32. The default maximum size of a compiled pattern is 64K. There have been a
4921 few cases of people hitting this limit. The code now uses macros to handle the
4922 storing of links as offsets within the compiled pattern. It defaults to 2-byte
4923 links, but this can be changed to 3 or 4 bytes by --with-link-size when
4924 configuring. Tests 2 and 5 work only with 2-byte links because they output
4925 debugging information about compiled patterns.
4927 33. Internal code re-arrangements:
4929 (a) Moved the debugging function for printing out a compiled regex into
4930 its own source file (printint.c) and used #include to pull it into
4931 pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
4932 separate copies.
4934 (b) Defined the list of op-code names for debugging as a macro in
4935 internal.h so that it is next to the definition of the opcodes.
4937 (c) Defined a table of op-code lengths for simpler skipping along compiled
4938 code. This is again a macro in internal.h so that it is next to the
4939 definition of the opcodes.
4941 34. Added support for recursive calls to individual subpatterns, along the
4942 lines of Robin Houston's patch (but implemented somewhat differently).
4944 35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
4945 allow it to read and process whole directories in Win32. This code was
4946 contributed by Lionel Fourquaux; it has not been tested by me.
4948 36. Added support for named subpatterns. The Python syntax (?P<name>...) is
4949 used to name a group. Names consist of alphanumerics and underscores, and must
4950 be unique. Back references use the syntax (?P=name) and recursive calls use
4951 (?P>name) which is a PCRE extension to the Python extension. Groups still have
4952 numbers. The function pcre_fullinfo() can be used after compilation to extract
4953 a name/number map. There are three relevant calls:
4955 PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
4956 PCRE_INFO_NAMECOUNT yields the number of entries
4957 PCRE_INFO_NAMETABLE yields a pointer to the map.
4959 The map is a vector of fixed-size entries. The size of each entry depends on
4960 the length of the longest name used. The first two bytes of each entry are the
4961 group number, most significant byte first. There follows the corresponding
4962 name, zero terminated. The names are in alphabetical order.
4964 37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
4965 case instead of 255. Making it the same both with and without UTF-8 support
4966 means that the same test output works with both.
4968 38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
4969 calling malloc() with a zero argument.
4971 39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
4972 optimization. I've improved things by keeping a bitmap of backreferences with
4973 numbers 1-31 so that if .* occurs inside capturing brackets that are not in
4974 fact referenced, the optimization can be applied. It is unlikely that a
4975 relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
4976 the match to follow \n) will appear inside brackets with a number greater than
4977 31, but if it does, any back reference > 31 suppresses the optimization.
4979 40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
4980 of disabling numbered capturing parentheses. Any opening parenthesis that is
4981 not followed by ? behaves as if it were followed by ?: but named parentheses
4982 can still be used for capturing (and they will acquire numbers in the usual
4983 way).
4985 41. Redesigned the return codes from the match() function into yes/no/error so
4986 that errors can be passed back from deep inside the nested calls. A malloc
4987 failure while inside a recursive subpattern call now causes the
4988 PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
4990 42. It is now possible to set a limit on the number of times the match()
4991 function is called in a call to pcre_exec(). This facility makes it possible to
4992 limit the amount of recursion and backtracking, though not in a directly
4993 obvious way, because the match() function is used in a number of different
4994 circumstances. The count starts from zero for each position in the subject
4995 string (for non-anchored patterns). The default limit is, for compatibility, a
4996 large number, namely 10 000 000. You can change this in two ways:
4998 (a) When configuring PCRE before making, you can use --with-match-limit=n
4999 to set a default value for the compiled library.
5001 (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
5002 a different value is set. See 45 below.
5004 If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
5006 43. Added a new function pcre_config(int, void *) to enable run-time extraction
5007 of things that can be changed at compile time. The first argument specifies
5008 what is wanted and the second points to where the information is to be placed.
5009 The current list of available information is:
5013 The output is an integer that is set to one if UTF-8 support is available;
5014 otherwise it is set to zero.
5018 The output is an integer that it set to the value of the code that is used for
5019 newline. It is either LF (10) or CR (13).
5023 The output is an integer that contains the number of bytes used for internal
5024 linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
5028 The output is an integer that contains the threshold above which the POSIX
5029 interface uses malloc() for output vectors. See item 31 above.
5033 The output is an unsigned integer that contains the default limit of the number
5034 of match() calls in a pcre_exec() execution. See 42 above.
5036 44. pcretest has been upgraded by the addition of the -C option. This causes it
5037 to extract all the available output from the new pcre_config() function, and to
5038 output it. The program then exits immediately.
5040 45. A need has arisen to pass over additional data with calls to pcre_exec() in
5041 order to support additional features. One way would have been to define
5042 pcre_exec2() (for example) with extra arguments, but this would not have been
5043 extensible, and would also have required all calls to the original function to
5044 be mapped to the new one. Instead, I have chosen to extend the mechanism that
5045 is used for passing in "extra" data from pcre_study().
5047 The pcre_extra structure is now exposed and defined in pcre.h. It currently
5048 contains the following fields:
5050 flags a bitmap indicating which of the following fields are set
5051 study_data opaque data from pcre_study()
5052 match_limit a way of specifying a limit on match() calls for a specific
5053 call to pcre_exec()
5054 callout_data data for callouts (see 49 below)
5056 The flag bits are also defined in pcre.h, and are
5062 The pcre_study() function now returns one of these new pcre_extra blocks, with
5063 the actual study data pointed to by the study_data field, and the
5064 PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
5065 before. That is, this change is entirely upwards-compatible and requires no
5066 change to existing code.
5068 If you want to pass in additional data to pcre_exec(), you can either place it
5069 in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
5070 block.
5072 46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
5073 data string contains the escape sequence \M, pcretest calls pcre_exec() several
5074 times with different match limits, until it finds the minimum value needed for
5075 pcre_exec() to complete. The value is then output. This can be instructive; for
5076 most simple matches the number is quite small, but for pathological cases it
5077 gets very large very quickly.
5079 47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
5080 returns the size of the data block pointed to by the study_data field in a
5081 pcre_extra block, that is, the value that was passed as the argument to
5082 pcre_malloc() when PCRE was getting memory in which to place the information
5083 created by pcre_study(). The fourth argument should point to a size_t variable.
5084 pcretest has been extended so that this information is shown after a successful
5085 pcre_study() call when information about the compiled regex is being displayed.
5087 48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
5088 because what follows is always an absolute path. (Later: it turns out that this
5089 is more than cosmetic for MinGW, because it doesn't like empty path
5090 components.)
5092 49. Some changes have been made to the callout feature (see 28 above):
5094 (i) A callout function now has three choices for what it returns:
5096 0 => success, carry on matching
5097 > 0 => failure at this point, but backtrack if possible
5098 < 0 => serious error, return this value from pcre_exec()
5100 Negative values should normally be chosen from the set of PCRE_ERROR_xxx
5101 values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
5102 "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
5103 use by callout functions. It will never be used by PCRE itself.
5105 (ii) The pcre_extra structure (see 45 above) has a void * field called
5106 callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
5107 pcre_callout_block structure has a field of the same name. The contents of
5108 the field passed in the pcre_extra structure are passed to the callout
5109 function in the corresponding field in the callout block. This makes it
5110 easier to use the same callout-containing regex from multiple threads. For
5111 testing, the pcretest program has a new data escape
5113 \C*n pass the number n (may be negative) as callout_data
5115 If the callout function in pcretest receives a non-zero value as
5116 callout_data, it returns that value.
5118 50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
5119 there were some redundant $(CFLAGS) in commands that are now specified as
5120 $(LINK), which already includes $(CFLAGS).
5122 51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
5123 has been compiled with UTF-8 support *and* pcre_compile() has been compiled
5124 with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
5125 one-byte characters throughout. Note that case-insensitive matching applies
5126 only to characters whose values are less than 256. PCRE doesn't support the
5127 notion of cases for higher-valued characters.
5129 (i) A character class whose characters are all within 0-255 is handled as
5130 a bit map, and the map is inverted for negative classes. Previously, a
5131 character > 255 always failed to match such a class; however it should
5132 match if the class was a negative one (e.g. [^ab]). This has been fixed.
5134 (ii) A negated character class with a single character < 255 is coded as
5135 "not this character" (OP_NOT). This wasn't working properly when the test
5136 character was multibyte, either singly or repeated.
5138 (iii) Repeats of multibyte characters are now handled correctly in UTF-8
5139 mode, for example: \x{100}{2,3}.
5141 (iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
5142 singly or repeated) now correctly test multibyte characters. However,
5143 PCRE doesn't recognize any characters with values greater than 255 as
5144 digits, spaces, or word characters. Such characters always match \D, \S,
5145 and \W, and never match \d, \s, or \w.
5147 (v) Classes may now contain characters and character ranges with values
5148 greater than 255. For example: [ab\x{100}-\x{400}].
5150 (vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
5151 PCRE in UTF-8 mode.
5153 52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
5154 PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
5155 retained for backwards compatibility. (Note that LASTLITERAL is also a byte
5156 value.)
5158 53. The single man page has become too large. I have therefore split it up into
5159 a number of separate man pages. These also give rise to individual HTML pages;
5160 these are now put in a separate directory, and there is an index.html page that
5161 lists them all. Some hyperlinking between the pages has been installed.
5163 54. Added convenience functions for handling named capturing parentheses.
5165 55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
5166 aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
5167 true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
5168 are faulted.
5170 56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
5171 calling configure. These values are used when compiling the dftables.c program
5172 which is run to generate the source of the default character tables. They
5173 default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
5174 you will need to set these values.
5176 57. Updated the building process for Windows DLL, as provided by Fred Cox.
5179 Version 3.9 02-Jan-02
5180 ---------------------
5182 1. A bit of extraneous text had somehow crept into the pcregrep documentation.
5184 2. If --disable-static was given, the building process failed when trying to
5185 build pcretest and pcregrep. (For some reason it was using libtool to compile
5186 them, which is not right, as they aren't part of the library.)
5189 Version 3.8 18-Dec-01
5190 ---------------------
5192 1. The experimental UTF-8 code was completely screwed up. It was packing the
5193 bytes in the wrong order. How dumb can you get?
5196 Version 3.7 29-Oct-01
5197 ---------------------
5199 1. In updating pcretest to check change 1 of version 3.6, I screwed up.
5200 This caused pcretest, when used on the test data, to segfault. Unfortunately,
5201 this didn't happen under Solaris 8, where I normally test things.
5203 2. The Makefile had to be changed to make it work on BSD systems, where 'make'
5204 doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
5205 isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
5206 this fix an hour or so after the initial 3.7 release.)
5209 Version 3.6 23-Oct-01
5210 ---------------------
5212 1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
5213 offsets passed as NULL with zero offset count.
5215 2. The config.guess and config.sub files had not been updated when I moved to
5216 the latest autoconf.
5219 Version 3.5 15-Aug-01
5220 ---------------------
5222 1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
5223 had been forgotten.
5225 2. By using declared but undefined structures, we can avoid using "void"
5226 definitions in pcre.h while keeping the internal definitions of the structures
5227 private.
5229 3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
5230 user point of view, this means that both static and shared libraries are built
5231 by default, but this can be individually controlled. More of the work of
5232 handling this static/shared cases is now inside libtool instead of PCRE's make
5233 file.
5235 4. The pcretest utility is now installed along with pcregrep because it is
5236 useful for users (to test regexs) and by doing this, it automatically gets
5237 relinked by libtool. The documentation has been turned into a man page, so
5238 there are now .1, .txt, and .html versions in /doc.
5240 5. Upgrades to pcregrep:
5241 (i) Added long-form option names like gnu grep.
5242 (ii) Added --help to list all options with an explanatory phrase.
5243 (iii) Added -r, --recursive to recurse into sub-directories.
5244 (iv) Added -f, --file to read patterns from a file.
5246 6. pcre_exec() was referring to its "code" argument before testing that
5247 argument for NULL (and giving an error if it was NULL).
5249 7. Upgraded Makefile.in to allow for compiling in a different directory from
5250 the source directory.
5252 8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
5253 options bits, the pointer it was passed was to an int instead of to an unsigned
5254 long int. This mattered only on 64-bit systems.
5256 9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
5257 generated) instead of pcre.in, which it its source. Also made the same change
5258 in several of the .c files.
5260 10. A new release of gcc defines printf() as a macro, which broke pcretest
5261 because it had an ifdef in the middle of a string argument for printf(). Fixed
5262 by using separate calls to printf().
5264 11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
5265 script, to force use of CR or LF instead of \n in the source. On non-Unix
5266 systems, the value can be set in config.h.
5268 12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
5269 absolute limit. Changed the text of the error message to make this clear, and
5270 likewise updated the man page.
5272 13. The limit of 99 on the number of capturing subpatterns has been removed.
5273 The new limit is 65535, which I hope will not be a "real" limit.
5276 Version 3.4 22-Aug-00
5277 ---------------------
5279 1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
5281 2. Diagnose condition (?(0) as an error instead of crashing on matching.
5284 Version 3.3 01-Aug-00
5285 ---------------------
5287 1. If an octal character was given, but the value was greater than \377, it
5288 was not getting masked to the least significant bits, as documented. This could
5289 lead to crashes in some systems.
5291 2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
5292 the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
5294 3. Added the functions pcre_free_substring() and pcre_free_substring_list().
5295 These just pass their arguments on to (pcre_free)(), but they are provided
5296 because some uses of PCRE bind it to non-C systems that can call its functions,
5297 but cannot call free() or pcre_free() directly.
5299 4. Add "make test" as a synonym for "make check". Corrected some comments in
5300 the Makefile.
5302 5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
5303 Makefile.
5305 6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
5306 command called pgrep for grepping around the active processes.
5308 7. Added the beginnings of support for UTF-8 character strings.
5310 8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
5311 RANLIB to ./ltconfig so that they are used by libtool. I think these are all
5312 the relevant ones. (AR is not passed because ./ltconfig does its own figuring
5313 out for the ar command.)
5316 Version 3.2 12-May-00
5317 ---------------------
5319 This is purely a bug fixing release.
5321 1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
5322 of ZA. This was just one example of several cases that could provoke this bug,
5323 which was introduced by change 9 of version 2.00. The code for breaking
5324 infinite loops after an iteration that matches an empty string was't working
5325 correctly.
5327 2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
5328 when matched against abbab (for example). After matching an empty string, it
5329 wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
5330 caused it to match further down the string than it should.
5332 3. The code contained an inclusion of sys/types.h. It isn't clear why this
5333 was there because it doesn't seem to be needed, and it causes trouble on some
5334 systems, as it is not a Standard C header. It has been removed.
5336 4. Made 4 silly changes to the source to avoid stupid compiler warnings that
5337 were reported on the Macintosh. The changes were from
5339 while ((c = *(++ptr)) != 0 && c != '\n');
5340 to
5341 while ((c = *(++ptr)) != 0 && c != '\n') ;
5343 Totally extraordinary, but if that's what it takes...
5345 5. PCRE is being used in one environment where neither memmove() nor bcopy() is
5346 available. Added HAVE_BCOPY and an autoconf test for it; if neither
5347 HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
5348 assumes the way PCRE uses memmove() (always moving upwards).
5350 6. PCRE is being used in one environment where strchr() is not available. There
5351 was only one use in pcre.c, and writing it out to avoid strchr() probably gives
5352 faster code anyway.
5355 Version 3.1 09-Feb-00
5356 ---------------------
5358 The only change in this release is the fixing of some bugs in Makefile.in for
5359 the "install" target:
5361 (1) It was failing to install pcreposix.h.
5363 (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
5366 Version 3.0 01-Feb-00
5367 ---------------------
5369 1. Add support for the /+ modifier to perltest (to output $` like it does in
5370 pcretest).
5372 2. Add support for the /g modifier to perltest.
5374 3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
5375 matches null strings.
5377 4. Fix perltest so that it doesn't do unwanted things when fed an empty
5378 pattern. Perl treats empty patterns specially - it reuses the most recent
5379 pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
5380 effect.
5382 5. The POSIX interface was broken in that it was just handing over the POSIX
5383 captured string vector to pcre_exec(), but (since release 2.00) PCRE has
5384 required a bigger vector, with some working space on the end. This means that
5385 the POSIX wrapper now has to get and free some memory, and copy the results.
5387 6. Added some simple autoconf support, placing the test data and the
5388 documentation in separate directories, re-organizing some of the
5389 information files, and making it build pcre-config (a GNU standard). Also added
5390 libtool support for building PCRE as a shared library, which is now the
5391 default.
5393 7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
5394 09 are not valid octal constants. Single digits will be used for minor values
5395 less than 10.
5397 8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
5398 existing programs that set these in the POSIX interface can use PCRE without
5399 modification.
5401 9. Added a new function, pcre_fullinfo() with an extensible interface. It can
5402 return all that pcre_info() returns, plus additional data. The pcre_info()
5403 function is retained for compatibility, but is considered to be obsolete.
5405 10. Added experimental recursion feature (?R) to handle one common case that
5406 Perl 5.6 will be able to do with (?p{...}).
5408 11. Added support for POSIX character classes like [:alpha:], which Perl is
5409 adopting.
5412 Version 2.08 31-Aug-99
5413 ----------------------
5415 1. When startoffset was not zero and the pattern began with ".*", PCRE was not
5416 trying to match at the startoffset position, but instead was moving forward to
5417 the next newline as if a previous match had failed.
5419 2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
5420 and could get into a loop if a null string was matched other than at the start
5421 of the subject.
5423 3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
5424 be distinguished at compile time, and for completeness also added PCRE_DATE.
5426 5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
5427 in GnuWin32 environments.
5430 Version 2.07 29-Jul-99
5431 ----------------------
5433 1. The documentation is now supplied in plain text form and HTML as well as in
5434 the form of man page sources.
5436 2. C++ compilers don't like assigning (void *) values to other pointer types.
5437 In particular this affects malloc(). Although there is no problem in Standard
5438 C, I've put in casts to keep C++ compilers happy.
5440 3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
5441 should be (const char *).
5443 4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
5444 be useful for non-Unix systems who don't want to bother with the POSIX stuff.
5445 However, I haven't made this a standard facility. The documentation doesn't
5446 mention it, and the Makefile doesn't support it.
5448 5. The Makefile now contains an "install" target, with editable destinations at
5449 the top of the file. The pcretest program is not installed.
5451 6. pgrep -V now gives the PCRE version number and date.
5453 7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
5454 causing the entire string to be ignored, instead of just the last character.
5456 8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
5457 non-matching string, it can take a very, very long time, even for strings of
5458 quite modest length, because of the nested recursion. PCRE now does better in
5459 some of these cases. It does this by remembering the last required literal
5460 character in the pattern, and pre-searching the subject to ensure it is present
5461 before running the real match. In other words, it applies a heuristic to detect
5462 some types of certain failure quickly, and in the above example, if presented
5463 with a string that has no trailing " it gives "no match" very quickly.
5465 9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
5466 other alternatives are tried instead.
5469 Version 2.06 09-Jun-99
5470 ----------------------
5472 1. Change pcretest's output for amount of store used to show just the code
5473 space, because the remainder (the data block) varies in size between 32-bit and
5474 64-bit systems.
5476 2. Added an extra argument to pcre_exec() to supply an offset in the subject to
5477 start matching at. This allows lookbehinds to work when searching for multiple
5478 occurrences in a string.
5480 3. Added additional options to pcretest for testing multiple occurrences:
5482 /+ outputs the rest of the string that follows a match
5483 /g loops for multiple occurrences, using the new startoffset argument
5484 /G loops for multiple occurrences by passing an incremented pointer
5486 4. PCRE wasn't doing the "first character" optimization for patterns starting
5487 with \b or \B, though it was doing it for other lookbehind assertions. That is,
5488 it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
5489 the letter 'x'. On long subject strings, this gives a significant speed-up.
5492 Version 2.05 21-Apr-99
5493 ----------------------
5495 1. Changed the type of magic_number from int to long int so that it works
5496 properly on 16-bit systems.
5498 2. Fixed a bug which caused patterns starting with .* not to work correctly
5499 when the subject string contained newline characters. PCRE was assuming
5500 anchoring for such patterns in all cases, which is not correct because .* will
5501 not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
5502 DOTALL is set at top level; otherwise it knows that patterns starting with .*
5503 must be retried after every newline in the subject.
5506 Version 2.04 18-Feb-99
5507 ----------------------
5509 1. For parenthesized subpatterns with repeats whose minimum was zero, the
5510 computation of the store needed to hold the pattern was incorrect (too large).
5511 If such patterns were nested a few deep, this could multiply and become a real
5512 problem.
5514 2. Added /M option to pcretest to show the memory requirement of a specific
5515 pattern. Made -m a synonym of -s (which does this globally) for compatibility.
5517 3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
5518 compiled in such a way that the backtracking after subsequent failure was
5519 pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
5520 ((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
5523 Version 2.03 02-Feb-99
5524 ----------------------
5526 1. Fixed typo and small mistake in man page.
5528 2. Added 4th condition (GPL supersedes if conflict) and created separate
5529 LICENCE file containing the conditions.
5531 3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
5532 Perl, that is the internal \ allows the delimiter to be included in the
5533 pattern. Locked out the use of \ as a delimiter. If \ immediately follows
5534 the final delimiter, add \ to the end of the pattern (to test the error).
5536 4. Added the convenience functions for extracting substrings after a successful
5537 match. Updated pcretest to make it able to test these functions.
5540 Version 2.02 14-Jan-99
5541 ----------------------
5543 1. Initialized the working variables associated with each extraction so that
5544 their saving and restoring doesn't refer to uninitialized store.
5546 2. Put dummy code into study.c in order to trick the optimizer of the IBM C
5547 compiler for OS/2 into generating correct code. Apparently IBM isn't going to
5548 fix the problem.
5550 3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
5551 calls, and wasn't printing the correct value for compiling calls. Increased the
5552 default value of LOOPREPEAT, and the number of significant figures in the
5553 times.
5555 4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
5557 5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
5558 a building problem on Windows NT with a FAT file system.
5561 Version 2.01 21-Oct-98
5562 ----------------------
5564 1. Changed the API for pcre_compile() to allow for the provision of a pointer
5565 to character tables built by pcre_maketables() in the current locale. If NULL
5566 is passed, the default tables are used.
5569 Version 2.00 24-Sep-98
5570 ----------------------
5572 1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
5573 it any more.
5575 2. Allow quantification of (?>) groups, and make it work correctly.
5577 3. The first character computation wasn't working for (?>) groups.
5579 4. Correct the implementation of \Z (it is permitted to match on the \n at the
5580 end of the subject) and add 5.005's \z, which really does match only at the
5581 very end of the subject.
5583 5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
5585 6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
5586 DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
5587 localized options. All options to pcre_study() were also removed.
5589 7. Add other new features from 5.005:
5591 $(?<= positive lookbehind
5592 $(?<! negative lookbehind
5593 (?imsx-imsx) added the unsetting capability
5594 such a setting is global if at outer level; local otherwise
5595 (?imsx-imsx:) non-capturing groups with option setting
5596 (?(cond)re|re) conditional pattern matching
5598 A backreference to itself in a repeated group matches the previous
5599 captured string.
5601 8. General tidying up of studying (both automatic and via "study")
5602 consequential on the addition of new assertions.
5604 9. As in 5.005, unlimited repeated groups that could match an empty substring
5605 are no longer faulted at compile time. Instead, the loop is forcibly broken at
5606 runtime if any iteration does actually match an empty substring.
5608 10. Include the RunTest script in the distribution.
5610 11. Added tests from the Perl 5.005_02 distribution. This showed up a few
5611 discrepancies, some of which were old and were also with respect to 5.004. They
5612 have now been fixed.
5615 Version 1.09 28-Apr-98
5616 ----------------------
5618 1. A negated single character class followed by a quantifier with a minimum
5619 value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
5620 program crashes, or just wrong answers. This did not apply to negated classes
5621 containing more than one character, or to minima other than one.
5624 Version 1.08 27-Mar-98
5625 ----------------------
5627 1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
5629 2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
5630 latter must appear before anything that relies on it in the pattern.
5633 Version 1.07 16-Feb-98
5634 ----------------------
5636 1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
5637 repeat of a potentially empty string).
5640 Version 1.06 23-Jan-98
5641 ----------------------
5643 1. Added Markus Oberhumer's little patches for C++.
5645 2. Literal strings longer than 255 characters were broken.
5648 Version 1.05 23-Dec-97
5649 ----------------------
5651 1. Negated character classes containing more than one character were failing if
5652 PCRE_CASELESS was set at run time.
5655 Version 1.04 19-Dec-97
5656 ----------------------
5658 1. Corrected the man page, where some "const" qualifiers had been omitted.
5660 2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
5661 input syntax.
5663 3. Fixed memory leak which occurred when a regex with back references was
5664 matched with an offsets vector that wasn't big enough. The temporary memory
5665 that is used in this case wasn't being freed if the match failed.
5667 4. Tidied pcretest to ensure it frees memory that it gets.
5669 5. Temporary memory was being obtained in the case where the passed offsets
5670 vector was exactly big enough.
5672 6. Corrected definition of offsetof() from change 5 below.
5674 7. I had screwed up change 6 below and broken the rules for the use of
5675 setjmp(). Now fixed.
5678 Version 1.03 18-Dec-97
5679 ----------------------
5681 1. A erroneous regex with a missing opening parenthesis was correctly
5682 diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
5683 on some systems.
5685 2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
5686 it was reported that one broken compiler failed on the former because "code" is
5687 also an independent variable.
5689 3. The erroneous regex a[]b caused an array overrun reference.
5691 4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
5692 fail on data ending with that character. (It was going on too far, and checking
5693 the next character, typically a binary zero.) This was specific to the
5694 optimized code for single-character negative classes.
5696 5. Added a contributed patch from the TIN world which does the following:
5698 + Add an undef for memmove, in case the the system defines a macro for it.
5700 + Add a definition of offsetof(), in case there isn't one. (I don't know
5701 the reason behind this - offsetof() is part of the ANSI standard - but
5702 it does no harm).
5704 + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
5705 most of the places where whitespace preceded '#'. I have given up and
5706 allowed the remaining 2 cases to be at the margin.
5708 + Rename some variables in pcre to eliminate shadowing. This seems very
5709 pedantic, but does no harm, of course.
5711 6. Moved the call to setjmp() into its own function, to get rid of warnings
5712 from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
5714 7. Constructs such as \d{8,} were compiling into the equivalent of
5715 \d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
5716 outcome, but in this particular case used more store than had been allocated,
5717 which caused the bug to be discovered because it threw up an internal error.
5719 8. The debugging code in both pcre and pcretest for outputting the compiled
5720 form of a regex was going wrong in the case of back references followed by
5721 curly-bracketed repeats.
5724 Version 1.02 12-Dec-97
5725 ----------------------
5727 1. Typos in pcre.3 and comments in the source fixed.
5729 2. Applied a contributed patch to get rid of places where it used to remove
5730 'const' from variables, and fixed some signed/unsigned and uninitialized
5731 variable warnings.
5733 3. Added the "runtest" target to Makefile.
5735 4. Set default compiler flag to -O2 rather than just -O.
5738 Version 1.01 19-Nov-97
5739 ----------------------
5741 1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
5742 like /([ab]*)*/, that is, for classes with more than one character in them.
5744 2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
5745 as /((?>a*))*/ (a PCRE_EXTRA facility).
5748 Version 1.00 18-Nov-97
5749 ----------------------
5751 1. Added compile-time macros to support systems such as SunOS4 which don't have
5752 memmove() or strerror() but have other things that can be used instead.
5754 2. Arranged that "make clean" removes the executables.
5757 Version 0.99 27-Oct-97
5758 ----------------------
5760 1. Fixed bug in code for optimizing classes with only one character. It was
5761 initializing a 32-byte map regardless, which could cause it to run off the end
5762 of the memory it had got.
5764 2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
5767 Version 0.98 22-Oct-97
5768 ----------------------
5770 1. Fixed bug in code for handling temporary memory usage when there are more
5771 back references than supplied space in the ovector. This could cause segfaults.
5774 Version 0.97 21-Oct-97
5775 ----------------------
5777 1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
5779 2. Optimized negated single characters not to use a bit map.
5781 3. Brought error texts together as macro definitions; clarified some of them;
5782 fixed one that was wrong - it said "range out of order" when it meant "invalid
5783 escape sequence".
5785 4. Changed some char * arguments to const char *.
5787 5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
5789 6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
5790 pcretest.
5793 Version 0.96 16-Oct-97
5794 ----------------------
5796 1. Added a simple "pgrep" utility to the distribution.
5798 2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
5799 unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
5800 where "ddd" means "one or more decimal digits".
5802 3. Fixed serious bug. If a pattern had a back reference, but the call to
5803 pcre_exec() didn't supply a large enough ovector to record the related
5804 identifying subpattern, the match always failed. PCRE now remembers the number
5805 of the largest back reference, and gets some temporary memory in which to save
5806 the offsets during matching if necessary, in order to ensure that
5807 backreferences always work.
5809 4. Increased the compatibility with Perl in a number of ways:
5811 (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
5812 to request this handling. The option can be set at compile or exec time.
5814 (b) $ matches before a terminating newline by default; an option
5815 PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
5816 mode). The option can be set at compile or exec time.
5818 (c) The handling of \ followed by a digit other than 0 is now supposed to be
5819 the same as Perl's. If the decimal number it represents is less than 10
5820 or there aren't that many previous left capturing parentheses, an octal
5821 escape is read. Inside a character class, it's always an octal escape,
5822 even if it is a single digit.
5824 (d) An escaped but undefined alphabetic character is taken as a literal,
5825 unless PCRE_EXTRA is set. Currently this just reserves the remaining
5826 escapes.
5828 (e) {0} is now permitted. (The previous item is removed from the compiled
5829 pattern).
5831 5. Changed all the names of code files so that the basic parts are no longer
5832 than 10 characters, and abolished the teeny "globals.c" file.
5834 6. Changed the handling of character classes; they are now done with a 32-byte
5835 bit map always.
5837 7. Added the -d and /D options to pcretest to make it possible to look at the
5838 internals of compilation without having to recompile pcre.
5841 Version 0.95 23-Sep-97
5842 ----------------------
5844 1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
5845 \x20 at the start of a run of normal characters. These were being treated as
5846 real characters, instead of the source characters being re-checked.
5849 Version 0.94 18-Sep-97
5850 ----------------------
5852 1. The functions are now thread-safe, with the caveat that the global variables
5853 containing pointers to malloc() and free() or alternative functions are the
5854 same for all threads.
5856 2. Get pcre_study() to generate a bitmap of initial characters for non-
5857 anchored patterns when this is possible, and use it if passed to pcre_exec().
5860 Version 0.93 15-Sep-97
5861 ----------------------
5863 1. /(b)|(:+)/ was computing an incorrect first character.
5865 2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
5866 but not actually doing anything yet.
5868 3. Treat "-" characters in classes that cannot be part of ranges as literals,
5869 as Perl does (e.g. [-az] or [az-]).
5871 4. Set the anchored flag if a branch starts with .* or .*? because that tests
5872 all possible positions.
5874 5. Split up into different modules to avoid including unneeded functions in a
5875 compiled binary. However, compile and exec are still in one module. The "study"
5876 function is split off.
5878 6. The character tables are now in a separate module whose source is generated
5879 by an auxiliary program - but can then be edited by hand if required. There are
5880 now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
5881 toupper() in the code.
5883 7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
5884 make them global. Abolish the function for setting them, as the caller can now
5885 set them directly.
5888 Version 0.92 11-Sep-97
5889 ----------------------
5891 1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
5892 (e.g. /a{1,3}/) was broken (I mis-optimized it).
5894 2. Caseless matching was not working in character classes if the characters in
5895 the pattern were in upper case.
5897 3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
5899 4. Make PCRE_ANCHORED public and accept as a compile option.
5901 5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
5902 PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
5903 pass them.
5905 6. Give an error if bad option bits passed at compile or run time.
5907 7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
5908 pcretest to cause it to pass that flag.
5910 8. Add pcre_info(), to get the number of identifying subpatterns, the stored
5911 options, and the first character, if set.
5913 9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
5916 Version 0.91 10-Sep-97
5917 ----------------------
5919 1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
5920 match the empty string as in /(a*)*/. It was looping and ultimately crashing.
5922 2. PCRE was looping on encountering an indefinitely repeated back reference to
5923 a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
5924 Perl does - treats the match as successful.
5926 ****


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