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Revision 355 - (show annotations) (download)
Mon Jul 7 17:45:23 2008 UTC (5 years, 9 months ago) by ph10
File size: 157365 byte(s)
Make pcretest generate a single byte for \x{} escapes in non-UTF-8 mode.

1 ChangeLog for PCRE
2 ------------------
3
4 Version 8.0 02 Jul-08
5 ---------------------
6
7 1. Replaced UCP searching code with optimized version as implemented for Ad
8 Muncher (http://www.admuncher.com/) by Peter Kankowski. This uses a two-
9 stage table and inline lookup instead of a function, giving speed ups of 2
10 to 5 times on some simple patterns that I tested. Permission was given to
11 distribute the MultiStage2.py script that generates the tables (it's not in
12 the tarball, but is in the Subversion repository).
13
14 2. Updated the Unicode datatables to Unicode 5.1.0. This adds yet more
15 scripts.
16
17 3. Change 12 for 7.7 introduced a bug in pcre_study() when a pattern contained
18 a group with a zero qualifier. The result of the study could be incorrect,
19 or the function might crash, depending on the pattern.
20
21 4. Caseless matching was not working for non-ASCII characters in back
22 references. For example, /(\x{de})\1/8i was not matching \x{de}\x{fe}.
23 It now works when Unicode Property Support is available.
24
25 5. In pcretest, an escape such as \x{de} in the data was always generating
26 a UTF-8 string, even in non-UTF-8 mode. Now it generates a single byte in
27 non-UTF-8 mode. If the value is greater than 255, it gives a warning about
28 truncation.
29
30
31 Version 7.7 07-May-08
32 ---------------------
33
34 1. Applied Craig's patch to sort out a long long problem: "If we can't convert
35 a string to a long long, pretend we don't even have a long long." This is
36 done by checking for the strtoq, strtoll, and _strtoi64 functions.
37
38 2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
39 pre-7.6 versions, which defined a global no_arg variable instead of putting
40 it in the RE class. (See also #8 below.)
41
42 3. Remove a line of dead code, identified by coverity and reported by Nuno
43 Lopes.
44
45 4. Fixed two related pcregrep bugs involving -r with --include or --exclude:
46
47 (1) The include/exclude patterns were being applied to the whole pathnames
48 of files, instead of just to the final components.
49
50 (2) If there was more than one level of directory, the subdirectories were
51 skipped unless they satisfied the include/exclude conditions. This is
52 inconsistent with GNU grep (and could even be seen as contrary to the
53 pcregrep specification - which I improved to make it absolutely clear).
54 The action now is always to scan all levels of directory, and just
55 apply the include/exclude patterns to regular files.
56
57 5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used
58 --exclude_dir in the tests to avoid scanning .svn directories.
59
60 6. Applied Craig's patch to the QuoteMeta function so that it escapes the
61 NUL character as backslash + 0 rather than backslash + NUL, because PCRE
62 doesn't support NULs in patterns.
63
64 7. Added some missing "const"s to declarations of static tables in
65 pcre_compile.c and pcre_dfa_exec.c.
66
67 8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
68 caused by fix #2 above. (Subsequently also a second patch to fix the
69 first patch. And a third patch - this was a messy problem.)
70
71 9. Applied Craig's patch to remove the use of push_back().
72
73 10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
74 matching function regexec().
75
76 11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
77 which, however, unlike Perl's \g{...}, are subroutine calls, not back
78 references. PCRE supports relative numbers with this syntax (I don't think
79 Oniguruma does).
80
81 12. Previously, a group with a zero repeat such as (...){0} was completely
82 omitted from the compiled regex. However, this means that if the group
83 was called as a subroutine from elsewhere in the pattern, things went wrong
84 (an internal error was given). Such groups are now left in the compiled
85 pattern, with a new opcode that causes them to be skipped at execution
86 time.
87
88 13. Added the PCRE_JAVASCRIPT_COMPAT option. This makes the following changes
89 to the way PCRE behaves:
90
91 (a) A lone ] character is dis-allowed (Perl treats it as data).
92
93 (b) A back reference to an unmatched subpattern matches an empty string
94 (Perl fails the current match path).
95
96 (c) A data ] in a character class must be notated as \] because if the
97 first data character in a class is ], it defines an empty class. (In
98 Perl it is not possible to have an empty class.) The empty class []
99 never matches; it forces failure and is equivalent to (*FAIL) or (?!).
100 The negative empty class [^] matches any one character, independently
101 of the DOTALL setting.
102
103 14. A pattern such as /(?2)[]a()b](abc)/ which had a forward reference to a
104 non-existent subpattern following a character class starting with ']' and
105 containing () gave an internal compiling error instead of "reference to
106 non-existent subpattern". Fortunately, when the pattern did exist, the
107 compiled code was correct. (When scanning forwards to check for the
108 existencd of the subpattern, it was treating the data ']' as terminating
109 the class, so got the count wrong. When actually compiling, the reference
110 was subsequently set up correctly.)
111
112 15. The "always fail" assertion (?!) is optimzed to (*FAIL) by pcre_compile;
113 it was being rejected as not supported by pcre_dfa_exec(), even though
114 other assertions are supported. I have made pcre_dfa_exec() support
115 (*FAIL).
116
117 16. The implementation of 13c above involved the invention of a new opcode,
118 OP_ALLANY, which is like OP_ANY but doesn't check the /s flag. Since /s
119 cannot be changed at match time, I realized I could make a small
120 improvement to matching performance by compiling OP_ALLANY instead of
121 OP_ANY for "." when DOTALL was set, and then removing the runtime tests
122 on the OP_ANY path.
123
124 17. Compiling pcretest on Windows with readline support failed without the
125 following two fixes: (1) Make the unistd.h include conditional on
126 HAVE_UNISTD_H; (2) #define isatty and fileno as _isatty and _fileno.
127
128 18. Changed CMakeLists.txt and cmake/FindReadline.cmake to arrange for the
129 ncurses library to be included for pcretest when ReadLine support is
130 requested, but also to allow for it to be overridden. This patch came from
131 Daniel Bergström.
132
133 19. There was a typo in the file ucpinternal.h where f0_rangeflag was defined
134 as 0x00f00000 instead of 0x00800000. Luckily, this would not have caused
135 any errors with the current Unicode tables. Thanks to Peter Kankowski for
136 spotting this.
137
138
139 Version 7.6 28-Jan-08
140 ---------------------
141
142 1. A character class containing a very large number of characters with
143 codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
144 overflow.
145
146 2. Patch to cut out the "long long" test in pcrecpp_unittest when
147 HAVE_LONG_LONG is not defined.
148
149 3. Applied Christian Ehrlicher's patch to update the CMake build files to
150 bring them up to date and include new features. This patch includes:
151
152 - Fixed PH's badly added libz and libbz2 support.
153 - Fixed a problem with static linking.
154 - Added pcredemo. [But later removed - see 7 below.]
155 - Fixed dftables problem and added an option.
156 - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
157 HAVE_LONG_LONG.
158 - Added readline support for pcretest.
159 - Added an listing of the option settings after cmake has run.
160
161 4. A user submitted a patch to Makefile that makes it easy to create
162 "pcre.dll" under mingw when using Configure/Make. I added stuff to
163 Makefile.am that cause it to include this special target, without
164 affecting anything else. Note that the same mingw target plus all
165 the other distribution libraries and programs are now supported
166 when configuring with CMake (see 6 below) instead of with
167 Configure/Make.
168
169 5. Applied Craig's patch that moves no_arg into the RE class in the C++ code.
170 This is an attempt to solve the reported problem "pcrecpp::no_arg is not
171 exported in the Windows port". It has not yet been confirmed that the patch
172 solves the problem, but it does no harm.
173
174 6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
175 NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
176 with CMake, and also correct the comment about stack recursion.
177
178 7. Remove the automatic building of pcredemo from the ./configure system and
179 from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
180 of a program that users should build themselves after PCRE is installed, so
181 building it automatically is not really right. What is more, it gave
182 trouble in some build environments.
183
184 8. Further tidies to CMakeLists.txt from Sheri and Christian.
185
186
187 Version 7.5 10-Jan-08
188 ---------------------
189
190 1. Applied a patch from Craig: "This patch makes it possible to 'ignore'
191 values in parens when parsing an RE using the C++ wrapper."
192
193 2. Negative specials like \S did not work in character classes in UTF-8 mode.
194 Characters greater than 255 were excluded from the class instead of being
195 included.
196
197 3. The same bug as (2) above applied to negated POSIX classes such as
198 [:^space:].
199
200 4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
201 defined or documented. It seems to have been a typo for PCRE_STATIC, so
202 I have changed it.
203
204 5. The construct (?&) was not diagnosed as a syntax error (it referenced the
205 first named subpattern) and a construct such as (?&a) would reference the
206 first named subpattern whose name started with "a" (in other words, the
207 length check was missing). Both these problems are fixed. "Subpattern name
208 expected" is now given for (?&) (a zero-length name), and this patch also
209 makes it give the same error for \k'' (previously it complained that that
210 was a reference to a non-existent subpattern).
211
212 6. The erroneous patterns (?+-a) and (?-+a) give different error messages;
213 this is right because (?- can be followed by option settings as well as by
214 digits. I have, however, made the messages clearer.
215
216 7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
217 than the number used in the conditional) now cause a compile-time error.
218 This is actually not compatible with Perl, which accepts such patterns, but
219 treats the conditional as always being FALSE (as PCRE used to), but it
220 seems to me that giving a diagnostic is better.
221
222 8. Change "alphameric" to the more common word "alphanumeric" in comments
223 and messages.
224
225 9. Fix two occurrences of "backslash" in comments that should have been
226 "backspace".
227
228 10. Remove two redundant lines of code that can never be obeyed (their function
229 was moved elsewhere).
230
231 11. The program that makes PCRE's Unicode character property table had a bug
232 which caused it to generate incorrect table entries for sequences of
233 characters that have the same character type, but are in different scripts.
234 It amalgamated them into a single range, with the script of the first of
235 them. In other words, some characters were in the wrong script. There were
236 thirteen such cases, affecting characters in the following ranges:
237
238 U+002b0 - U+002c1
239 U+0060c - U+0060d
240 U+0061e - U+00612
241 U+0064b - U+0065e
242 U+0074d - U+0076d
243 U+01800 - U+01805
244 U+01d00 - U+01d77
245 U+01d9b - U+01dbf
246 U+0200b - U+0200f
247 U+030fc - U+030fe
248 U+03260 - U+0327f
249 U+0fb46 - U+0fbb1
250 U+10450 - U+1049d
251
252 12. The -o option (show only the matching part of a line) for pcregrep was not
253 compatible with GNU grep in that, if there was more than one match in a
254 line, it showed only the first of them. It now behaves in the same way as
255 GNU grep.
256
257 13. If the -o and -v options were combined for pcregrep, it printed a blank
258 line for every non-matching line. GNU grep prints nothing, and pcregrep now
259 does the same. The return code can be used to tell if there were any
260 non-matching lines.
261
262 14. Added --file-offsets and --line-offsets to pcregrep.
263
264 15. The pattern (?=something)(?R) was not being diagnosed as a potentially
265 infinitely looping recursion. The bug was that positive lookaheads were not
266 being skipped when checking for a possible empty match (negative lookaheads
267 and both kinds of lookbehind were skipped).
268
269 16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
270 inclusion of <windows.h> to before rather than after the definition of
271 INVALID_FILE_ATTRIBUTES (patch from David Byron).
272
273 17. Specifying a possessive quantifier with a specific limit for a Unicode
274 character property caused pcre_compile() to compile bad code, which led at
275 runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
276 are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
277 caused the error; without that there was no problem.
278
279 18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
280
281 19. Added --enable-pcretest-libreadline.
282
283 20. In pcrecpp.cc, the variable 'count' was incremented twice in
284 RE::GlobalReplace(). As a result, the number of replacements returned was
285 double what it should be. I removed one of the increments, but Craig sent a
286 later patch that removed the other one (the right fix) and added unit tests
287 that check the return values (which was not done before).
288
289 21. Several CMake things:
290
291 (1) Arranged that, when cmake is used on Unix, the libraries end up with
292 the names libpcre and libpcreposix, not just pcre and pcreposix.
293
294 (2) The above change means that pcretest and pcregrep are now correctly
295 linked with the newly-built libraries, not previously installed ones.
296
297 (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
298
299 22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
300 crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
301 UTF-8 newline character). The key issue is that the pattern starts .*;
302 this means that the match must be either at the beginning, or after a
303 newline. The bug was in the code for advancing after a failed match and
304 checking that the new position followed a newline. It was not taking
305 account of UTF-8 characters correctly.
306
307 23. PCRE was behaving differently from Perl in the way it recognized POSIX
308 character classes. PCRE was not treating the sequence [:...:] as a
309 character class unless the ... were all letters. Perl, however, seems to
310 allow any characters between [: and :], though of course it rejects as
311 unknown any "names" that contain non-letters, because all the known class
312 names consist only of letters. Thus, Perl gives an error for [[:1234:]],
313 for example, whereas PCRE did not - it did not recognize a POSIX character
314 class. This seemed a bit dangerous, so the code has been changed to be
315 closer to Perl. The behaviour is not identical to Perl, because PCRE will
316 diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
317 treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
318 Perl does, and where it didn't before.
319
320 24. Rewrite so as to remove the single use of %n from pcregrep because in some
321 Windows environments %n is disabled by default.
322
323
324 Version 7.4 21-Sep-07
325 ---------------------
326
327 1. Change 7.3/28 was implemented for classes by looking at the bitmap. This
328 means that a class such as [\s] counted as "explicit reference to CR or
329 LF". That isn't really right - the whole point of the change was to try to
330 help when there was an actual mention of one of the two characters. So now
331 the change happens only if \r or \n (or a literal CR or LF) character is
332 encountered.
333
334 2. The 32-bit options word was also used for 6 internal flags, but the numbers
335 of both had grown to the point where there were only 3 bits left.
336 Fortunately, there was spare space in the data structure, and so I have
337 moved the internal flags into a new 16-bit field to free up more option
338 bits.
339
340 3. The appearance of (?J) at the start of a pattern set the DUPNAMES option,
341 but did not set the internal JCHANGED flag - either of these is enough to
342 control the way the "get" function works - but the PCRE_INFO_JCHANGED
343 facility is supposed to tell if (?J) was ever used, so now (?J) at the
344 start sets both bits.
345
346 4. Added options (at build time, compile time, exec time) to change \R from
347 matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
348
349 5. doc/pcresyntax.html was missing from the distribution.
350
351 6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
352 compatibility, even though it is no longer used.
353
354 7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
355 strtoull to pcrecpp.cc to select the available functions in WIN32 when the
356 windows.h file is present (where different names are used). [This was
357 reversed later after testing - see 16 below.]
358
359 8. Changed all #include <config.h> to #include "config.h". There were also
360 some further <pcre.h> cases that I changed to "pcre.h".
361
362 9. When pcregrep was used with the --colour option, it missed the line ending
363 sequence off the lines that it output.
364
365 10. It was pointed out to me that arrays of string pointers cause lots of
366 relocations when a shared library is dynamically loaded. A technique of
367 using a single long string with a table of offsets can drastically reduce
368 these. I have refactored PCRE in four places to do this. The result is
369 dramatic:
370
371 Originally: 290
372 After changing UCP table: 187
373 After changing error message table: 43
374 After changing table of "verbs" 36
375 After changing table of Posix names 22
376
377 Thanks to the folks working on Gregex for glib for this insight.
378
379 11. --disable-stack-for-recursion caused compiling to fail unless -enable-
380 unicode-properties was also set.
381
382 12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
383
384 13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
385 checked only for CRLF.
386
387 14. Added casts to pcretest.c to avoid compiler warnings.
388
389 15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
390
391 16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
392 and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
393 entirely. This removes changes made in 7 above.
394
395 17. The CMake files have been updated, and there is now more information about
396 building with CMake in the NON-UNIX-USE document.
397
398
399 Version 7.3 28-Aug-07
400 ---------------------
401
402 1. In the rejigging of the build system that eventually resulted in 7.1, the
403 line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
404 brackets there is not right, since it causes compilers to look for an
405 installed pcre.h, not the version that is in the source that is being
406 compiled (which of course may be different). I have changed it back to:
407
408 #include "pcre.h"
409
410 I have a vague recollection that the change was concerned with compiling in
411 different directories, but in the new build system, that is taken care of
412 by the VPATH setting the Makefile.
413
414 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
415 when the subject happened to end in the byte 0x85 (e.g. if the last
416 character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
417 characters but of course it shouldn't be taken as a newline when it is part
418 of another character. The bug was that, for an unlimited repeat of . in
419 not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
420 characters when looking for a newline.
421
422 3. A small performance improvement in the DOTALL UTF-8 mode .* case.
423
424 4. Debugging: adjusted the names of opcodes for different kinds of parentheses
425 in debug output.
426
427 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
428 long printing in the pcrecpp unittest when running under MinGW.
429
430 6. ESC_K was left out of the EBCDIC table.
431
432 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
433 parentheses; I made it 1000, which seemed large enough. Unfortunately, the
434 limit also applies to "virtual nesting" when a pattern is recursive, and in
435 this case 1000 isn't so big. I have been able to remove this limit at the
436 expense of backing off one optimization in certain circumstances. Normally,
437 when pcre_exec() would call its internal match() function recursively and
438 immediately return the result unconditionally, it uses a "tail recursion"
439 feature to save stack. However, when a subpattern that can match an empty
440 string has an unlimited repetition quantifier, it no longer makes this
441 optimization. That gives it a stack frame in which to save the data for
442 checking that an empty string has been matched. Previously this was taken
443 from the 1000-entry workspace that had been reserved. So now there is no
444 explicit limit, but more stack is used.
445
446 8. Applied Daniel's patches to solve problems with the import/export magic
447 syntax that is required for Windows, and which was going wrong for the
448 pcreposix and pcrecpp parts of the library. These were overlooked when this
449 problem was solved for the main library.
450
451 9. There were some crude static tests to avoid integer overflow when computing
452 the size of patterns that contain repeated groups with explicit upper
453 limits. As the maximum quantifier is 65535, the maximum group length was
454 set at 30,000 so that the product of these two numbers did not overflow a
455 32-bit integer. However, it turns out that people want to use groups that
456 are longer than 30,000 bytes (though not repeat them that many times).
457 Change 7.0/17 (the refactoring of the way the pattern size is computed) has
458 made it possible to implement the integer overflow checks in a much more
459 dynamic way, which I have now done. The artificial limitation on group
460 length has been removed - we now have only the limit on the total length of
461 the compiled pattern, which depends on the LINK_SIZE setting.
462
463 10. Fixed a bug in the documentation for get/copy named substring when
464 duplicate names are permitted. If none of the named substrings are set, the
465 functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
466 empty string.
467
468 11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
469 instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
470 because the ] is interpreted as the first data character and the
471 terminating ] is not found. PCRE has been made compatible with Perl in this
472 regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
473 cause memory overwriting.
474
475 10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
476 string has been matched (to stop an infinite loop). It was not recognizing
477 a conditional subpattern that could match an empty string if that
478 subpattern was within another subpattern. For example, it looped when
479 trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the
480 condition was not nested. This bug has been fixed.
481
482 12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
483 past the start of the subject in the presence of bytes with the top bit
484 set, for example "\x8aBCD".
485
486 13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
487 (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
488
489 14. Optimized (?!) to (*FAIL).
490
491 15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
492 This restricts code points to be within the range 0 to 0x10FFFF, excluding
493 the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
494 full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
495 does: it's just the validity check that is more restrictive.
496
497 16. Inserted checks for integer overflows during escape sequence (backslash)
498 processing, and also fixed erroneous offset values for syntax errors during
499 backslash processing.
500
501 17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
502 for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
503
504 18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
505 caused an overrun.
506
507 19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
508 something other than just ASCII characters) inside a group that had an
509 unlimited repeat caused a loop at compile time (while checking to see
510 whether the group could match an empty string).
511
512 20. Debugging a pattern containing \p or \P could cause a crash. For example,
513 [\P{Any}] did so. (Error in the code for printing property names.)
514
515 21. An orphan \E inside a character class could cause a crash.
516
517 22. A repeated capturing bracket such as (A)? could cause a wild memory
518 reference during compilation.
519
520 23. There are several functions in pcre_compile() that scan along a compiled
521 expression for various reasons (e.g. to see if it's fixed length for look
522 behind). There were bugs in these functions when a repeated \p or \P was
523 present in the pattern. These operators have additional parameters compared
524 with \d, etc, and these were not being taken into account when moving along
525 the compiled data. Specifically:
526
527 (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
528 length.
529
530 (b) An item such as \pL+ within a repeated group could cause crashes or
531 loops.
532
533 (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
534 "reference to non-existent subpattern" error.
535
536 (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
537
538 24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
539 characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
540
541 25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
542
543 26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
544 character were causing crashes (broken optimization).
545
546 27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
547 \p or \P) caused a compile-time loop.
548
549 28. More problems have arisen in unanchored patterns when CRLF is a valid line
550 break. For example, the unstudied pattern [\r\n]A does not match the string
551 "\r\nA" because change 7.0/46 below moves the current point on by two
552 characters after failing to match at the start. However, the pattern \nA
553 *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
554 the same is true. There doesn't seem any very clean way out of this, but
555 what I have chosen to do makes the common cases work: PCRE now takes note
556 of whether there can be an explicit match for \r or \n anywhere in the
557 pattern, and if so, 7.0/46 no longer applies. As part of this change,
558 there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
559 pattern has explicit CR or LF references.
560
561 29. Added (*CR) etc for changing newline setting at start of pattern.
562
563
564 Version 7.2 19-Jun-07
565 ---------------------
566
567 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
568 which is apparently normally available under Windows.
569
570 2. Re-jig the pcregrep tests with different newline settings in an attempt
571 to make them independent of the local environment's newline setting.
572
573 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
574
575 4. Some of the "internals" tests were previously cut out when the link size
576 was not 2, because the output contained actual offsets. The recent new
577 "Z" feature of pcretest means that these can be cut out, making the tests
578 usable with all link sizes.
579
580 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
581 stack recursion. This gives a massive performance boost under BSD, but just
582 a small improvement under Linux. However, it saves one field in the frame
583 in all cases.
584
585 6. Added more features from the forthcoming Perl 5.10:
586
587 (a) (?-n) (where n is a string of digits) is a relative subroutine or
588 recursion call. It refers to the nth most recently opened parentheses.
589
590 (b) (?+n) is also a relative subroutine call; it refers to the nth next
591 to be opened parentheses.
592
593 (c) Conditions that refer to capturing parentheses can be specified
594 relatively, for example, (?(-2)... or (?(+3)...
595
596 (d) \K resets the start of the current match so that everything before
597 is not part of it.
598
599 (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
600
601 (f) \g{name} is another synonym - part of Perl 5.10's unification of
602 reference syntax.
603
604 (g) (?| introduces a group in which the numbering of parentheses in each
605 alternative starts with the same number.
606
607 (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
608
609 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
610 PCRE_INFO_JCHANGED.
611
612 8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not
613 terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
614 for detecting groups that can match an empty string.
615
616 9. A pattern with a very large number of alternatives (more than several
617 hundred) was running out of internal workspace during the pre-compile
618 phase, where pcre_compile() figures out how much memory will be needed. A
619 bit of new cunning has reduced the workspace needed for groups with
620 alternatives. The 1000-alternative test pattern now uses 12 bytes of
621 workspace instead of running out of the 4096 that are available.
622
623 10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
624
625 11. Applied patch from Google to remove an optimization that didn't quite work.
626 The report of the bug said:
627
628 pcrecpp::RE("a*").FullMatch("aaa") matches, while
629 pcrecpp::RE("a*?").FullMatch("aaa") does not, and
630 pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
631
632 12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
633 it matched the wrong number of bytes.
634
635
636 Version 7.1 24-Apr-07
637 ---------------------
638
639 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
640 that is more "standard", making use of automake and other Autotools. There
641 is some re-arrangement of the files and adjustment of comments consequent
642 on this.
643
644 2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
645 for recursive directory scanning broke on some systems because the files
646 are not scanned in any specific order and on different systems the order
647 was different. A call to "sort" has been inserted into RunGrepTest for the
648 approprate test as a short-term fix. In the longer term there may be an
649 alternative.
650
651 3. I had an email from Eric Raymond about problems translating some of PCRE's
652 man pages to HTML (despite the fact that I distribute HTML pages, some
653 people do their own conversions for various reasons). The problems
654 concerned the use of low-level troff macros .br and .in. I have therefore
655 removed all such uses from the man pages (some were redundant, some could
656 be replaced by .nf/.fi pairs). The 132html script that I use to generate
657 HTML has been updated to handle .nf/.fi and to complain if it encounters
658 .br or .in.
659
660 4. Updated comments in configure.ac that get placed in config.h.in and also
661 arranged for config.h to be included in the distribution, with the name
662 config.h.generic, for the benefit of those who have to compile without
663 Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
664
665 5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
666 Weber: (1) pcre_internal.h was missing some function renames; (2) updated
667 makevp.bat for the current PCRE, using the additional files
668 makevp_c.txt, makevp_l.txt, and pcregexp.pas.
669
670 6. A Windows user reported a minor discrepancy with test 2, which turned out
671 to be caused by a trailing space on an input line that had got lost in his
672 copy. The trailing space was an accident, so I've just removed it.
673
674 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
675 that is needed.
676
677 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
678 as "const" (a) because they are and (b) because it helps the PHP
679 maintainers who have recently made a script to detect big data structures
680 in the php code that should be moved to the .rodata section. I remembered
681 to update Builducptable as well, so it won't revert if ucptable.h is ever
682 re-created.
683
684 9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
685 pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
686 order to be able to cut out the UTF-8 tables in the latter when UTF-8
687 support is not required. This saves 1.5-2K of code, which is important in
688 some applications.
689
690 Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
691 so as not to refer to the tables, even though these functions will never be
692 called when UTF-8 support is disabled. Otherwise there are problems with a
693 shared library.
694
695 10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
696
697 (a) It was defining its arguments as char * instead of void *.
698
699 (b) It was assuming that all moves were upwards in memory; this was true
700 a long time ago when I wrote it, but is no longer the case.
701
702 The emulated memove() is provided for those environments that have neither
703 memmove() nor bcopy(). I didn't think anyone used it these days, but that
704 is clearly not the case, as these two bugs were recently reported.
705
706 11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
707 and Detrail to create the HTML documentation, the .txt form of the man
708 pages, and it removes trailing spaces from listed files. It also creates
709 pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
710 case, it wraps all the #defines with #ifndefs. This script should be run
711 before "make dist".
712
713 12. Fixed two fairly obscure bugs concerned with quantified caseless matching
714 with Unicode property support.
715
716 (a) For a maximizing quantifier, if the two different cases of the
717 character were of different lengths in their UTF-8 codings (there are
718 some cases like this - I found 11), and the matching function had to
719 back up over a mixture of the two cases, it incorrectly assumed they
720 were both the same length.
721
722 (b) When PCRE was configured to use the heap rather than the stack for
723 recursion during matching, it was not correctly preserving the data for
724 the other case of a UTF-8 character when checking ahead for a match
725 while processing a minimizing repeat. If the check also involved
726 matching a wide character, but failed, corruption could cause an
727 erroneous result when trying to check for a repeat of the original
728 character.
729
730 13. Some tidying changes to the testing mechanism:
731
732 (a) The RunTest script now detects the internal link size and whether there
733 is UTF-8 and UCP support by running ./pcretest -C instead of relying on
734 values substituted by "configure". (The RunGrepTest script already did
735 this for UTF-8.) The configure.ac script no longer substitutes the
736 relevant variables.
737
738 (b) The debugging options /B and /D in pcretest show the compiled bytecode
739 with length and offset values. This means that the output is different
740 for different internal link sizes. Test 2 is skipped for link sizes
741 other than 2 because of this, bypassing the problem. Unfortunately,
742 there was also a test in test 3 (the locale tests) that used /B and
743 failed for link sizes other than 2. Rather than cut the whole test out,
744 I have added a new /Z option to pcretest that replaces the length and
745 offset values with spaces. This is now used to make test 3 independent
746 of link size. (Test 2 will be tidied up later.)
747
748 14. If erroroffset was passed as NULL to pcre_compile, it provoked a
749 segmentation fault instead of returning the appropriate error message.
750
751 15. In multiline mode when the newline sequence was set to "any", the pattern
752 ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
753 This doesn't seem right; it now treats the CRLF combination as the line
754 ending, and so does not match in that case. It's only a pattern such as ^$
755 that would hit this one: something like ^ABC$ would have failed after \r
756 and then tried again after \r\n.
757
758 16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
759 in an attempt to make files that differ only in their line terminators
760 compare equal. This works on Linux.
761
762 17. Under certain error circumstances pcregrep might try to free random memory
763 as it exited. This is now fixed, thanks to valgrind.
764
765 19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
766 "abc\r\n\r\n", it found an unwanted second match after the second \r. This
767 was because its rules for how to advance for /g after matching an empty
768 string at the end of a line did not allow for this case. They now check for
769 it specially.
770
771 20. pcretest is supposed to handle patterns and data of any length, by
772 extending its buffers when necessary. It was getting this wrong when the
773 buffer for a data line had to be extended.
774
775 21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
776 CRLF as a newline sequence.
777
778 22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
779 out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
780 I have nevertheless tidied it up.
781
782 23. Added some casts to kill warnings from HP-UX ia64 compiler.
783
784 24. Added a man page for pcre-config.
785
786
787 Version 7.0 19-Dec-06
788 ---------------------
789
790 1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
791 moving to gcc 4.1.1.
792
793 2. The -S option for pcretest uses setrlimit(); I had omitted to #include
794 sys/time.h, which is documented as needed for this function. It doesn't
795 seem to matter on Linux, but it showed up on some releases of OS X.
796
797 3. It seems that there are systems where bytes whose values are greater than
798 127 match isprint() in the "C" locale. The "C" locale should be the
799 default when a C program starts up. In most systems, only ASCII printing
800 characters match isprint(). This difference caused the output from pcretest
801 to vary, making some of the tests fail. I have changed pcretest so that:
802
803 (a) When it is outputting text in the compiled version of a pattern, bytes
804 other than 32-126 are always shown as hex escapes.
805
806 (b) When it is outputting text that is a matched part of a subject string,
807 it does the same, unless a different locale has been set for the match
808 (using the /L modifier). In this case, it uses isprint() to decide.
809
810 4. Fixed a major bug that caused incorrect computation of the amount of memory
811 required for a compiled pattern when options that changed within the
812 pattern affected the logic of the preliminary scan that determines the
813 length. The relevant options are -x, and -i in UTF-8 mode. The result was
814 that the computed length was too small. The symptoms of this bug were
815 either the PCRE error "internal error: code overflow" from pcre_compile(),
816 or a glibc crash with a message such as "pcretest: free(): invalid next
817 size (fast)". Examples of patterns that provoked this bug (shown in
818 pcretest format) are:
819
820 /(?-x: )/x
821 /(?x)(?-x: \s*#\s*)/
822 /((?i)[\x{c0}])/8
823 /(?i:[\x{c0}])/8
824
825 HOWEVER: Change 17 below makes this fix obsolete as the memory computation
826 is now done differently.
827
828 5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
829 wrapper classes; (b) implement a new function in the C++ scanner that is
830 more efficient than the old way of doing things because it avoids levels of
831 recursion in the regex matching; (c) add a paragraph to the documentation
832 for the FullMatch() function.
833
834 6. The escape sequence \n was being treated as whatever was defined as
835 "newline". Not only was this contrary to the documentation, which states
836 that \n is character 10 (hex 0A), but it also went horribly wrong when
837 "newline" was defined as CRLF. This has been fixed.
838
839 7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
840 was being set to -1 for the "end of line" case (supposedly a value that no
841 character can have). Though this value is never used (the check for end of
842 line is "zero bytes in current character"), it caused compiler complaints.
843 I've changed it to 0xffffffff.
844
845 8. In pcre_version.c, the version string was being built by a sequence of
846 C macros that, in the event of PCRE_PRERELEASE being defined as an empty
847 string (as it is for production releases) called a macro with an empty
848 argument. The C standard says the result of this is undefined. The gcc
849 compiler treats it as an empty string (which was what was wanted) but it is
850 reported that Visual C gives an error. The source has been hacked around to
851 avoid this problem.
852
853 9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
854 builds of pcretest, and changed the call to _setmode() to use _O_BINARY
855 instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
856 of them did).
857
858 10. Originally, pcretest opened its input and output without "b"; then I was
859 told that "b" was needed in some environments, so it was added for release
860 5.0 to both the input and output. (It makes no difference on Unix-like
861 systems.) Later I was told that it is wrong for the input on Windows. I've
862 now abstracted the modes into two macros, to make it easier to fiddle with
863 them, and removed "b" from the input mode under Windows.
864
865 11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
866
867 12. Added -help and --help to pcretest as an official way of being reminded
868 of the options.
869
870 13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
871 and pcrecpp.cc because they annoy compilers at high warning levels.
872
873 14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
874
875 15. Fixed an occurrence of == in configure.ac that should have been = (shell
876 scripts are not C programs :-) and which was not noticed because it works
877 on Linux.
878
879 16. pcretest is supposed to handle any length of pattern and data line (as one
880 line or as a continued sequence of lines) by extending its input buffer if
881 necessary. This feature was broken for very long pattern lines, leading to
882 a string of junk being passed to pcre_compile() if the pattern was longer
883 than about 50K.
884
885 17. I have done a major re-factoring of the way pcre_compile() computes the
886 amount of memory needed for a compiled pattern. Previously, there was code
887 that made a preliminary scan of the pattern in order to do this. That was
888 OK when PCRE was new, but as the facilities have expanded, it has become
889 harder and harder to keep it in step with the real compile phase, and there
890 have been a number of bugs (see for example, 4 above). I have now found a
891 cunning way of running the real compile function in a "fake" mode that
892 enables it to compute how much memory it would need, while actually only
893 ever using a few hundred bytes of working memory and without too many
894 tests of the mode. This should make future maintenance and development
895 easier. A side effect of this work is that the limit of 200 on the nesting
896 depth of parentheses has been removed (though this was never a serious
897 limitation, I suspect). However, there is a downside: pcre_compile() now
898 runs more slowly than before (30% or more, depending on the pattern). I
899 hope this isn't a big issue. There is no effect on runtime performance.
900
901 18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
902 newline (only possible for the last line of a file) and it was a
903 pattern that set a locale (followed by /Lsomething), pcretest crashed.
904
905 19. Added additional timing features to pcretest. (1) The -tm option now times
906 matching only, not compiling. (2) Both -t and -tm can be followed, as a
907 separate command line item, by a number that specifies the number of
908 repeats to use when timing. The default is 50000; this gives better
909 precision, but takes uncomfortably long for very large patterns.
910
911 20. Extended pcre_study() to be more clever in cases where a branch of a
912 subpattern has no definite first character. For example, (a*|b*)[cd] would
913 previously give no result from pcre_study(). Now it recognizes that the
914 first character must be a, b, c, or d.
915
916 21. There was an incorrect error "recursive call could loop indefinitely" if
917 a subpattern (or the entire pattern) that was being tested for matching an
918 empty string contained only one non-empty item after a nested subpattern.
919 For example, the pattern (?>\x{100}*)\d(?R) provoked this error
920 incorrectly, because the \d was being skipped in the check.
921
922 22. The pcretest program now has a new pattern option /B and a command line
923 option -b, which is equivalent to adding /B to every pattern. This causes
924 it to show the compiled bytecode, without the additional information that
925 -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
926 is the same as /B/I).
927
928 23. A new optimization is now able automatically to treat some sequences such
929 as a*b as a*+b. More specifically, if something simple (such as a character
930 or a simple class like \d) has an unlimited quantifier, and is followed by
931 something that cannot possibly match the quantified thing, the quantifier
932 is automatically "possessified".
933
934 24. A recursive reference to a subpattern whose number was greater than 39
935 went wrong under certain circumstances in UTF-8 mode. This bug could also
936 have affected the operation of pcre_study().
937
938 25. Realized that a little bit of performance could be had by replacing
939 (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
940
941 26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
942
943 27. Possessive quantifiers such as a++ were previously implemented by turning
944 them into atomic groups such as ($>a+). Now they have their own opcodes,
945 which improves performance. This includes the automatically created ones
946 from 23 above.
947
948 28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
949 lookahead was broken if it was not anchored. PCRE was mistakenly expecting
950 the first matched character to be a colon. This applied both to named and
951 numbered groups.
952
953 29. The ucpinternal.h header file was missing its idempotency #ifdef.
954
955 30. I was sent a "project" file called libpcre.a.dev which I understand makes
956 building PCRE on Windows easier, so I have included it in the distribution.
957
958 31. There is now a check in pcretest against a ridiculously large number being
959 returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
960 loop, the loop is abandoned.
961
962 32. Forward references to subpatterns in conditions such as (?(2)...) where
963 subpattern 2 is defined later cause pcre_compile() to search forwards in
964 the pattern for the relevant set of parentheses. This search went wrong
965 when there were unescaped parentheses in a character class, parentheses
966 escaped with \Q...\E, or parentheses in a #-comment in /x mode.
967
968 33. "Subroutine" calls and backreferences were previously restricted to
969 referencing subpatterns earlier in the regex. This restriction has now
970 been removed.
971
972 34. Added a number of extra features that are going to be in Perl 5.10. On the
973 whole, these are just syntactic alternatives for features that PCRE had
974 previously implemented using the Python syntax or my own invention. The
975 other formats are all retained for compatibility.
976
977 (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
978 as (?P<name>...). The new forms, as well as being in Perl 5.10, are
979 also .NET compatible.
980
981 (b) A recursion or subroutine call to a named group can now be defined as
982 (?&name) as well as (?P>name).
983
984 (c) A backreference to a named group can now be defined as \k<name> or
985 \k'name' as well as (?P=name). The new forms, as well as being in Perl
986 5.10, are also .NET compatible.
987
988 (d) A conditional reference to a named group can now use the syntax
989 (?(<name>) or (?('name') as well as (?(name).
990
991 (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
992 groups (named and numbered) that are never evaluated inline, but can be
993 called as "subroutines" from elsewhere. In effect, the DEFINE condition
994 is always false. There may be only one alternative in such a group.
995
996 (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
997 as the simple (?(R). The condition is true only if the most recent
998 recursion is that of the given number or name. It does not search out
999 through the entire recursion stack.
1000
1001 (g) The escape \gN or \g{N} has been added, where N is a positive or
1002 negative number, specifying an absolute or relative reference.
1003
1004 35. Tidied to get rid of some further signed/unsigned compiler warnings and
1005 some "unreachable code" warnings.
1006
1007 36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
1008 things, this adds five new scripts.
1009
1010 37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
1011 There were also incompatibilities regarding the handling of \Q..\E inside
1012 character classes, for example with patterns like [\Qa\E-\Qz\E] where the
1013 hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
1014
1015 38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
1016 matches an empty string, and forcibly breaks the loop. There were bugs in
1017 this code in non-simple cases. For a pattern such as ^(a()*)* matched
1018 against aaaa the result was just "a" rather than "aaaa", for example. Two
1019 separate and independent bugs (that affected different cases) have been
1020 fixed.
1021
1022 39. Refactored the code to abolish the use of different opcodes for small
1023 capturing bracket numbers. This is a tidy that I avoided doing when I
1024 removed the limit on the number of capturing brackets for 3.5 back in 2001.
1025 The new approach is not only tidier, it makes it possible to reduce the
1026 memory needed to fix the previous bug (38).
1027
1028 40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
1029 sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
1030 processing dot, circumflex, or dollar metacharacters, or #-comments in /x
1031 mode.
1032
1033 41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
1034 report.
1035
1036 42. Applied patch, originally from Ari Pollak, modified by Google, to allow
1037 copy construction and assignment in the C++ wrapper.
1038
1039 43. Updated pcregrep to support "--newline=any". In the process, I fixed a
1040 couple of bugs that could have given wrong results in the "--newline=crlf"
1041 case.
1042
1043 44. Added a number of casts and did some reorganization of signed/unsigned int
1044 variables following suggestions from Dair Grant. Also renamed the variable
1045 "this" as "item" because it is a C++ keyword.
1046
1047 45. Arranged for dftables to add
1048
1049 #include "pcre_internal.h"
1050
1051 to pcre_chartables.c because without it, gcc 4.x may remove the array
1052 definition from the final binary if PCRE is built into a static library and
1053 dead code stripping is activated.
1054
1055 46. For an unanchored pattern, if a match attempt fails at the start of a
1056 newline sequence, and the newline setting is CRLF or ANY, and the next two
1057 characters are CRLF, advance by two characters instead of one.
1058
1059
1060 Version 6.7 04-Jul-06
1061 ---------------------
1062
1063 1. In order to handle tests when input lines are enormously long, pcretest has
1064 been re-factored so that it automatically extends its buffers when
1065 necessary. The code is crude, but this _is_ just a test program. The
1066 default size has been increased from 32K to 50K.
1067
1068 2. The code in pcre_study() was using the value of the re argument before
1069 testing it for NULL. (Of course, in any sensible call of the function, it
1070 won't be NULL.)
1071
1072 3. The memmove() emulation function in pcre_internal.h, which is used on
1073 systems that lack both memmove() and bcopy() - that is, hardly ever -
1074 was missing a "static" storage class specifier.
1075
1076 4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
1077 containing an extended class (one that cannot be represented by a bitmap
1078 because it contains high-valued characters or Unicode property items, e.g.
1079 [\pZ]). Almost always one would set UTF-8 mode when processing such a
1080 pattern, but PCRE should not loop if you do not (it no longer does).
1081 [Detail: two cases were found: (a) a repeated subpattern containing an
1082 extended class; (b) a recursive reference to a subpattern that followed a
1083 previous extended class. It wasn't skipping over the extended class
1084 correctly when UTF-8 mode was not set.]
1085
1086 5. A negated single-character class was not being recognized as fixed-length
1087 in lookbehind assertions such as (?<=[^f]), leading to an incorrect
1088 compile error "lookbehind assertion is not fixed length".
1089
1090 6. The RunPerlTest auxiliary script was showing an unexpected difference
1091 between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
1092 write a Perl script that can interpret lines of an input file either as
1093 byte characters or as UTF-8, which is what "perltest" was being required to
1094 do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
1095 can't do is switch easily at run time between having the "use utf8;" pragma
1096 or not. In the end, I fudged it by using the RunPerlTest script to insert
1097 "use utf8;" explicitly for the UTF-8 tests.
1098
1099 7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
1100 the end of the subject string, contrary to the documentation and to what
1101 Perl does. This was true of both matching functions. Now it matches only at
1102 the start of the subject and immediately after *internal* newlines.
1103
1104 8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
1105 a pointer to an int instead of a pointer to an unsigned long int. This
1106 caused problems on 64-bit systems.
1107
1108 9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
1109 instance of the 'standard' template library not being so standard".
1110
1111 10. There was no check on the number of named subpatterns nor the maximum
1112 length of a subpattern name. The product of these values is used to compute
1113 the size of the memory block for a compiled pattern. By supplying a very
1114 long subpattern name and a large number of named subpatterns, the size
1115 computation could be caused to overflow. This is now prevented by limiting
1116 the length of names to 32 characters, and the number of named subpatterns
1117 to 10,000.
1118
1119 11. Subpatterns that are repeated with specific counts have to be replicated in
1120 the compiled pattern. The size of memory for this was computed from the
1121 length of the subpattern and the repeat count. The latter is limited to
1122 65535, but there was no limit on the former, meaning that integer overflow
1123 could in principle occur. The compiled length of a repeated subpattern is
1124 now limited to 30,000 bytes in order to prevent this.
1125
1126 12. Added the optional facility to have named substrings with the same name.
1127
1128 13. Added the ability to use a named substring as a condition, using the
1129 Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
1130 are numbers (not recommended). Forward references are permitted.
1131
1132 14. Added forward references in named backreferences (if you see what I mean).
1133
1134 15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
1135 pattern could run off the end of the subject. For example, the pattern
1136 "(?s)(.{1,5})"8 did this with the subject "ab".
1137
1138 16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
1139 PCRE_CASELESS was set when matching characters that were quantified with ?
1140 or *.
1141
1142 17. A character class other than a single negated character that had a minimum
1143 but no maximum quantifier - for example [ab]{6,} - was not handled
1144 correctly by pce_dfa_exec(). It would match only one character.
1145
1146 18. A valid (though odd) pattern that looked like a POSIX character
1147 class but used an invalid character after [ (for example [[,abc,]]) caused
1148 pcre_compile() to give the error "Failed: internal error: code overflow" or
1149 in some cases to crash with a glibc free() error. This could even happen if
1150 the pattern terminated after [[ but there just happened to be a sequence of
1151 letters, a binary zero, and a closing ] in the memory that followed.
1152
1153 19. Perl's treatment of octal escapes in the range \400 to \777 has changed
1154 over the years. Originally (before any Unicode support), just the bottom 8
1155 bits were taken. Thus, for example, \500 really meant \100. Nowadays the
1156 output from "man perlunicode" includes this:
1157
1158 The regular expression compiler produces polymorphic opcodes. That
1159 is, the pattern adapts to the data and automatically switches to
1160 the Unicode character scheme when presented with Unicode data--or
1161 instead uses a traditional byte scheme when presented with byte
1162 data.
1163
1164 Sadly, a wide octal escape does not cause a switch, and in a string with
1165 no other multibyte characters, these octal escapes are treated as before.
1166 Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern
1167 /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
1168 Unicode string.
1169
1170 I have not perpetrated such confusion in PCRE. Up till now, it took just
1171 the bottom 8 bits, as in old Perl. I have now made octal escapes with
1172 values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
1173 translate to the appropriate multibyte character.
1174
1175 29. Applied some refactoring to reduce the number of warnings from Microsoft
1176 and Borland compilers. This has included removing the fudge introduced
1177 seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
1178 a warning about an unused variable.
1179
1180 21. PCRE has not included VT (character 0x0b) in the set of whitespace
1181 characters since release 4.0, because Perl (from release 5.004) does not.
1182 [Or at least, is documented not to: some releases seem to be in conflict
1183 with the documentation.] However, when a pattern was studied with
1184 pcre_study() and all its branches started with \s, PCRE still included VT
1185 as a possible starting character. Of course, this did no harm; it just
1186 caused an unnecessary match attempt.
1187
1188 22. Removed a now-redundant internal flag bit that recorded the fact that case
1189 dependency changed within the pattern. This was once needed for "required
1190 byte" processing, but is no longer used. This recovers a now-scarce options
1191 bit. Also moved the least significant internal flag bit to the most-
1192 significant bit of the word, which was not previously used (hangover from
1193 the days when it was an int rather than a uint) to free up another bit for
1194 the future.
1195
1196 23. Added support for CRLF line endings as well as CR and LF. As well as the
1197 default being selectable at build time, it can now be changed at runtime
1198 via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
1199 specify that it is scanning data with non-default line endings.
1200
1201 24. Changed the definition of CXXLINK to make it agree with the definition of
1202 LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
1203
1204 25. Applied Ian Taylor's patches to avoid using another stack frame for tail
1205 recursions. This makes a big different to stack usage for some patterns.
1206
1207 26. If a subpattern containing a named recursion or subroutine reference such
1208 as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
1209 the space required for the compiled pattern went wrong and gave too small a
1210 value. Depending on the environment, this could lead to "Failed: internal
1211 error: code overflow at offset 49" or "glibc detected double free or
1212 corruption" errors.
1213
1214 27. Applied patches from Google (a) to support the new newline modes and (b) to
1215 advance over multibyte UTF-8 characters in GlobalReplace.
1216
1217 28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
1218 difference for some implementation of PCRE in some Windows version.
1219
1220 29. Added some extra testing facilities to pcretest:
1221
1222 \q<number> in a data line sets the "match limit" value
1223 \Q<number> in a data line sets the "match recursion limt" value
1224 -S <number> sets the stack size, where <number> is in megabytes
1225
1226 The -S option isn't available for Windows.
1227
1228
1229 Version 6.6 06-Feb-06
1230 ---------------------
1231
1232 1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
1233 in pcreposix.h. I have copied the definition from pcre.h.
1234
1235 2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
1236 because pcre.h is no longer a built file.
1237
1238 3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
1239 not normally included in the compiled code.
1240
1241
1242 Version 6.5 01-Feb-06
1243 ---------------------
1244
1245 1. When using the partial match feature with pcre_dfa_exec(), it was not
1246 anchoring the second and subsequent partial matches at the new starting
1247 point. This could lead to incorrect results. For example, with the pattern
1248 /1234/, partially matching against "123" and then "a4" gave a match.
1249
1250 2. Changes to pcregrep:
1251
1252 (a) All non-match returns from pcre_exec() were being treated as failures
1253 to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
1254 error message is output. Some extra information is given for the
1255 PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are
1256 probably the only errors that are likely to be caused by users (by
1257 specifying a regex that has nested indefinite repeats, for instance).
1258 If there are more than 20 of these errors, pcregrep is abandoned.
1259
1260 (b) A binary zero was treated as data while matching, but terminated the
1261 output line if it was written out. This has been fixed: binary zeroes
1262 are now no different to any other data bytes.
1263
1264 (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
1265 used to set a locale for matching. The --locale=xxxx long option has
1266 been added (no short equivalent) to specify a locale explicitly on the
1267 pcregrep command, overriding the environment variables.
1268
1269 (d) When -B was used with -n, some line numbers in the output were one less
1270 than they should have been.
1271
1272 (e) Added the -o (--only-matching) option.
1273
1274 (f) If -A or -C was used with -c (count only), some lines of context were
1275 accidentally printed for the final match.
1276
1277 (g) Added the -H (--with-filename) option.
1278
1279 (h) The combination of options -rh failed to suppress file names for files
1280 that were found from directory arguments.
1281
1282 (i) Added the -D (--devices) and -d (--directories) options.
1283
1284 (j) Added the -F (--fixed-strings) option.
1285
1286 (k) Allow "-" to be used as a file name for -f as well as for a data file.
1287
1288 (l) Added the --colo(u)r option.
1289
1290 (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
1291 is not present by default.
1292
1293 3. A nasty bug was discovered in the handling of recursive patterns, that is,
1294 items such as (?R) or (?1), when the recursion could match a number of
1295 alternatives. If it matched one of the alternatives, but subsequently,
1296 outside the recursion, there was a failure, the code tried to back up into
1297 the recursion. However, because of the way PCRE is implemented, this is not
1298 possible, and the result was an incorrect result from the match.
1299
1300 In order to prevent this happening, the specification of recursion has
1301 been changed so that all such subpatterns are automatically treated as
1302 atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
1303
1304 4. I had overlooked the fact that, in some locales, there are characters for
1305 which isalpha() is true but neither isupper() nor islower() are true. In
1306 the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
1307 and ordfeminine) are like this. This affected the treatment of \w and \W
1308 when they appeared in character classes, but not when they appeared outside
1309 a character class. The bit map for "word" characters is now created
1310 separately from the results of isalnum() instead of just taking it from the
1311 upper, lower, and digit maps. (Plus the underscore character, of course.)
1312
1313 5. The above bug also affected the handling of POSIX character classes such as
1314 [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
1315 permanent tables. Instead, the bit maps for such a class were previously
1316 created as the appropriate unions of the upper, lower, and digit bitmaps.
1317 Now they are created by subtraction from the [[:word:]] class, which has
1318 its own bitmap.
1319
1320 6. The [[:blank:]] character class matches horizontal, but not vertical space.
1321 It is created by subtracting the vertical space characters (\x09, \x0a,
1322 \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
1323 subtraction was done in the overall bitmap for a character class, meaning
1324 that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
1325 be recognized. This bug has been fixed.
1326
1327 7. Patches from the folks at Google:
1328
1329 (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
1330 real life, but is still worth protecting against".
1331
1332 (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
1333 regular expressions".
1334
1335 (c) pcre_scanner.cc: avoid use of std::count() because not all systems
1336 have it.
1337
1338 (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
1339 "configure" and the latter not, in order to fix a problem somebody had
1340 with compiling the Arg class on HP-UX.
1341
1342 (e) Improve the error-handling of the C++ wrapper a little bit.
1343
1344 (f) New tests for checking recursion limiting.
1345
1346 8. The pcre_memmove() function, which is used only if the environment does not
1347 have a standard memmove() function (and is therefore rarely compiled),
1348 contained two bugs: (a) use of int instead of size_t, and (b) it was not
1349 returning a result (though PCRE never actually uses the result).
1350
1351 9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
1352 large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
1353 returned instead of calling malloc() with an overflowing number that would
1354 most likely cause subsequent chaos.
1355
1356 10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
1357
1358 11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
1359 with this option is matched, the nmatch and pmatch options of regexec() are
1360 ignored.
1361
1362 12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
1363 provided in case anyone wants to the the POSIX interface with UTF-8
1364 strings.
1365
1366 13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
1367 C++ linking (needed for some HP-UX environments).
1368
1369 14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
1370 (unused parameter) and in the pcre_printint() function (omitted "default"
1371 switch label when the default is to do nothing).
1372
1373 15. Added some code to make it possible, when PCRE is compiled as a C++
1374 library, to replace subject pointers for pcre_exec() with a smart pointer
1375 class, thus making it possible to process discontinuous strings.
1376
1377 16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
1378 much the same function. They were added by different people who were trying
1379 to make PCRE easy to compile on non-Unix systems. It has been suggested
1380 that PCRE_EXPORT be abolished now that there is more automatic apparatus
1381 for compiling on Windows systems. I have therefore replaced it with
1382 PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
1383 defaults to "extern" for C or "extern C" for C++, which works fine on
1384 Unix-like systems. It is now possible to override the value of PCRE_DATA_
1385 SCOPE with something explicit in config.h. In addition:
1386
1387 (a) pcreposix.h still had just "extern" instead of either of these macros;
1388 I have replaced it with PCRE_DATA_SCOPE.
1389
1390 (b) Functions such as _pcre_xclass(), which are internal to the library,
1391 but external in the C sense, all had PCRE_EXPORT in their definitions.
1392 This is apparently wrong for the Windows case, so I have removed it.
1393 (It makes no difference on Unix-like systems.)
1394
1395 17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
1396 of recursive calls to match(). This is different to MATCH_LIMIT because
1397 that limits the total number of calls to match(), not all of which increase
1398 the depth of recursion. Limiting the recursion depth limits the amount of
1399 stack (or heap if NO_RECURSE is set) that is used. The default can be set
1400 when PCRE is compiled, and changed at run time. A patch from Google adds
1401 this functionality to the C++ interface.
1402
1403 18. Changes to the handling of Unicode character properties:
1404
1405 (a) Updated the table to Unicode 4.1.0.
1406
1407 (b) Recognize characters that are not in the table as "Cn" (undefined).
1408
1409 (c) I revised the way the table is implemented to a much improved format
1410 which includes recognition of ranges. It now supports the ranges that
1411 are defined in UnicodeData.txt, and it also amalgamates other
1412 characters into ranges. This has reduced the number of entries in the
1413 table from around 16,000 to around 3,000, thus reducing its size
1414 considerably. I realized I did not need to use a tree structure after
1415 all - a binary chop search is just as efficient. Having reduced the
1416 number of entries, I extended their size from 6 bytes to 8 bytes to
1417 allow for more data.
1418
1419 (d) Added support for Unicode script names via properties such as \p{Han}.
1420
1421 19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
1422 matching that character.
1423
1424 20. When matching a repeated Unicode property with a minimum greater than zero,
1425 (for example \pL{2,}), PCRE could look past the end of the subject if it
1426 reached it while seeking the minimum number of characters. This could
1427 happen only if some of the characters were more than one byte long, because
1428 there is a check for at least the minimum number of bytes.
1429
1430 21. Refactored the implementation of \p and \P so as to be more general, to
1431 allow for more different types of property in future. This has changed the
1432 compiled form incompatibly. Anybody with saved compiled patterns that use
1433 \p or \P will have to recompile them.
1434
1435 22. Added "Any" and "L&" to the supported property types.
1436
1437 23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
1438 but give a compile time error if the value is greater than 0xff.
1439
1440 24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
1441 accidentally not being installed or uninstalled.
1442
1443 25. The pcre.h file was built from pcre.h.in, but the only changes that were
1444 made were to insert the current release number. This seemed silly, because
1445 it made things harder for people building PCRE on systems that don't run
1446 "configure". I have turned pcre.h into a distributed file, no longer built
1447 by "configure", with the version identification directly included. There is
1448 no longer a pcre.h.in file.
1449
1450 However, this change necessitated a change to the pcre-config script as
1451 well. It is built from pcre-config.in, and one of the substitutions was the
1452 release number. I have updated configure.ac so that ./configure now finds
1453 the release number by grepping pcre.h.
1454
1455 26. Added the ability to run the tests under valgrind.
1456
1457
1458 Version 6.4 05-Sep-05
1459 ---------------------
1460
1461 1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
1462 "--" to be printed when multiple files were scanned, even when none of the
1463 -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
1464 consider it to be a bug, and have restored the previous behaviour.
1465
1466 2. A couple of code tidies to get rid of compiler warnings.
1467
1468 3. The pcretest program used to cheat by referring to symbols in the library
1469 whose names begin with _pcre_. These are internal symbols that are not
1470 really supposed to be visible externally, and in some environments it is
1471 possible to suppress them. The cheating is now confined to including
1472 certain files from the library's source, which is a bit cleaner.
1473
1474 4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
1475 file's purpose clearer.
1476
1477 5. Reorganized pcre_ucp_findchar().
1478
1479
1480 Version 6.3 15-Aug-05
1481 ---------------------
1482
1483 1. The file libpcre.pc.in did not have general read permission in the tarball.
1484
1485 2. There were some problems when building without C++ support:
1486
1487 (a) If C++ support was not built, "make install" and "make test" still
1488 tried to test it.
1489
1490 (b) There were problems when the value of CXX was explicitly set. Some
1491 changes have been made to try to fix these, and ...
1492
1493 (c) --disable-cpp can now be used to explicitly disable C++ support.
1494
1495 (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
1496 backslash in a target when C++ was disabled. This confuses some
1497 versions of "make", apparently. Using an intermediate variable solves
1498 this. (Same for CPP_LOBJ.)
1499
1500 3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
1501 (non-Windows) now includes $(CFLAGS) because these flags are sometimes
1502 necessary on certain architectures.
1503
1504 4. Added a setting of -export-symbols-regex to the link command to remove
1505 those symbols that are exported in the C sense, but actually are local
1506 within the library, and not documented. Their names all begin with
1507 "_pcre_". This is not a perfect job, because (a) we have to except some
1508 symbols that pcretest ("illegally") uses, and (b) the facility isn't always
1509 available (and never for static libraries). I have made a note to try to
1510 find a way round (a) in the future.
1511
1512
1513 Version 6.2 01-Aug-05
1514 ---------------------
1515
1516 1. There was no test for integer overflow of quantifier values. A construction
1517 such as {1111111111111111} would give undefined results. What is worse, if
1518 a minimum quantifier for a parenthesized subpattern overflowed and became
1519 negative, the calculation of the memory size went wrong. This could have
1520 led to memory overwriting.
1521
1522 2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
1523
1524 3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
1525 operating environments where this matters.
1526
1527 4. Applied Giuseppe Maxia's patch to add additional features for controlling
1528 PCRE options from within the C++ wrapper.
1529
1530 5. Named capturing subpatterns were not being correctly counted when a pattern
1531 was compiled. This caused two problems: (a) If there were more than 100
1532 such subpatterns, the calculation of the memory needed for the whole
1533 compiled pattern went wrong, leading to an overflow error. (b) Numerical
1534 back references of the form \12, where the number was greater than 9, were
1535 not recognized as back references, even though there were sufficient
1536 previous subpatterns.
1537
1538 6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
1539 versions of gcc, e.g. 2.95.4.
1540
1541
1542 Version 6.1 21-Jun-05
1543 ---------------------
1544
1545 1. There was one reference to the variable "posix" in pcretest.c that was not
1546 surrounded by "#if !defined NOPOSIX".
1547
1548 2. Make it possible to compile pcretest without DFA support, UTF8 support, or
1549 the cross-check on the old pcre_info() function, for the benefit of the
1550 cut-down version of PCRE that is currently imported into Exim.
1551
1552 3. A (silly) pattern starting with (?i)(?-i) caused an internal space
1553 allocation error. I've done the easy fix, which wastes 2 bytes for sensible
1554 patterns that start (?i) but I don't think that matters. The use of (?i) is
1555 just an example; this all applies to the other options as well.
1556
1557 4. Since libtool seems to echo the compile commands it is issuing, the output
1558 from "make" can be reduced a bit by putting "@" in front of each libtool
1559 compile command.
1560
1561 5. Patch from the folks at Google for configure.in to be a bit more thorough
1562 in checking for a suitable C++ installation before trying to compile the
1563 C++ stuff. This should fix a reported problem when a compiler was present,
1564 but no suitable headers.
1565
1566 6. The man pages all had just "PCRE" as their title. I have changed them to
1567 be the relevant file name. I have also arranged that these names are
1568 retained in the file doc/pcre.txt, which is a concatenation in text format
1569 of all the man pages except the little individual ones for each function.
1570
1571 7. The NON-UNIX-USE file had not been updated for the different set of source
1572 files that come with release 6. I also added a few comments about the C++
1573 wrapper.
1574
1575
1576 Version 6.0 07-Jun-05
1577 ---------------------
1578
1579 1. Some minor internal re-organization to help with my DFA experiments.
1580
1581 2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
1582 didn't matter for the library itself when fully configured, but did matter
1583 when compiling without UCP support, or within Exim, where the ucp files are
1584 not imported.
1585
1586 3. Refactoring of the library code to split up the various functions into
1587 different source modules. The addition of the new DFA matching code (see
1588 below) to a single monolithic source would have made it really too
1589 unwieldy, quite apart from causing all the code to be include in a
1590 statically linked application, when only some functions are used. This is
1591 relevant even without the DFA addition now that patterns can be compiled in
1592 one application and matched in another.
1593
1594 The downside of splitting up is that there have to be some external
1595 functions and data tables that are used internally in different modules of
1596 the library but which are not part of the API. These have all had their
1597 names changed to start with "_pcre_" so that they are unlikely to clash
1598 with other external names.
1599
1600 4. Added an alternate matching function, pcre_dfa_exec(), which matches using
1601 a different (DFA) algorithm. Although it is slower than the original
1602 function, it does have some advantages for certain types of matching
1603 problem.
1604
1605 5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
1606 including restarting after a partial match.
1607
1608 6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
1609 defined when compiling for Windows was sent to me. I have put it into the
1610 code, though I have no means of testing or verifying it.
1611
1612 7. Added the pcre_refcount() auxiliary function.
1613
1614 8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
1615 match before or at the first newline in the subject string. In pcretest,
1616 the /f option on a pattern can be used to set this.
1617
1618 9. A repeated \w when used in UTF-8 mode with characters greater than 256
1619 would behave wrongly. This has been present in PCRE since release 4.0.
1620
1621 10. A number of changes to the pcregrep command:
1622
1623 (a) Refactored how -x works; insert ^(...)$ instead of setting
1624 PCRE_ANCHORED and checking the length, in preparation for adding
1625 something similar for -w.
1626
1627 (b) Added the -w (match as a word) option.
1628
1629 (c) Refactored the way lines are read and buffered so as to have more
1630 than one at a time available.
1631
1632 (d) Implemented a pcregrep test script.
1633
1634 (e) Added the -M (multiline match) option. This allows patterns to match
1635 over several lines of the subject. The buffering ensures that at least
1636 8K, or the rest of the document (whichever is the shorter) is available
1637 for matching (and similarly the previous 8K for lookbehind assertions).
1638
1639 (f) Changed the --help output so that it now says
1640
1641 -w, --word-regex(p)
1642
1643 instead of two lines, one with "regex" and the other with "regexp"
1644 because that confused at least one person since the short forms are the
1645 same. (This required a bit of code, as the output is generated
1646 automatically from a table. It wasn't just a text change.)
1647
1648 (g) -- can be used to terminate pcregrep options if the next thing isn't an
1649 option but starts with a hyphen. Could be a pattern or a path name
1650 starting with a hyphen, for instance.
1651
1652 (h) "-" can be given as a file name to represent stdin.
1653
1654 (i) When file names are being printed, "(standard input)" is used for
1655 the standard input, for compatibility with GNU grep. Previously
1656 "<stdin>" was used.
1657
1658 (j) The option --label=xxx can be used to supply a name to be used for
1659 stdin when file names are being printed. There is no short form.
1660
1661 (k) Re-factored the options decoding logic because we are going to add
1662 two more options that take data. Such options can now be given in four
1663 different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
1664
1665 (l) Added the -A, -B, and -C options for requesting that lines of context
1666 around matches be printed.
1667
1668 (m) Added the -L option to print the names of files that do not contain
1669 any matching lines, that is, the complement of -l.
1670
1671 (n) The return code is 2 if any file cannot be opened, but pcregrep does
1672 continue to scan other files.
1673
1674 (o) The -s option was incorrectly implemented. For compatibility with other
1675 greps, it now suppresses the error message for a non-existent or non-
1676 accessible file (but not the return code). There is a new option called
1677 -q that suppresses the output of matching lines, which was what -s was
1678 previously doing.
1679
1680 (p) Added --include and --exclude options to specify files for inclusion
1681 and exclusion when recursing.
1682
1683 11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
1684 Hopefully, it now does.
1685
1686 12. Missing cast in pcre_study().
1687
1688 13. Added an "uninstall" target to the makefile.
1689
1690 14. Replaced "extern" in the function prototypes in Makefile.in with
1691 "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
1692 world, but is set differently for Windows.
1693
1694 15. Added a second compiling function called pcre_compile2(). The only
1695 difference is that it has an extra argument, which is a pointer to an
1696 integer error code. When there is a compile-time failure, this is set
1697 non-zero, in addition to the error test pointer being set to point to an
1698 error message. The new argument may be NULL if no error number is required
1699 (but then you may as well call pcre_compile(), which is now just a
1700 wrapper). This facility is provided because some applications need a
1701 numeric error indication, but it has also enabled me to tidy up the way
1702 compile-time errors are handled in the POSIX wrapper.
1703
1704 16. Added VPATH=.libs to the makefile; this should help when building with one
1705 prefix path and installing with another. (Or so I'm told by someone who
1706 knows more about this stuff than I do.)
1707
1708 17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
1709 passes PCRE_DOTALL to the pcre_compile() function, making the "." character
1710 match everything, including newlines. This is not POSIX-compatible, but
1711 somebody wanted the feature. From pcretest it can be activated by using
1712 both the P and the s flags.
1713
1714 18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
1715
1716 19. libpcre.pc was being incorrectly installed as executable.
1717
1718 20. A couple of places in pcretest check for end-of-line by looking for '\n';
1719 it now also looks for '\r' so that it will work unmodified on Windows.
1720
1721 21. Added Google's contributed C++ wrapper to the distribution.
1722
1723 22. Added some untidy missing memory free() calls in pcretest, to keep
1724 Electric Fence happy when testing.
1725
1726
1727
1728 Version 5.0 13-Sep-04
1729 ---------------------
1730
1731 1. Internal change: literal characters are no longer packed up into items
1732 containing multiple characters in a single byte-string. Each character
1733 is now matched using a separate opcode. However, there may be more than one
1734 byte in the character in UTF-8 mode.
1735
1736 2. The pcre_callout_block structure has two new fields: pattern_position and
1737 next_item_length. These contain the offset in the pattern to the next match
1738 item, and its length, respectively.
1739
1740 3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
1741 insertion of callouts before each pattern item. Added the /C option to
1742 pcretest to make use of this.
1743
1744 4. On the advice of a Windows user, the lines
1745
1746 #if defined(_WIN32) || defined(WIN32)
1747 _setmode( _fileno( stdout ), 0x8000 );
1748 #endif /* defined(_WIN32) || defined(WIN32) */
1749
1750 have been added to the source of pcretest. This apparently does useful
1751 magic in relation to line terminators.
1752
1753 5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
1754 for the benefit of those environments where the "b" makes a difference.
1755
1756 6. The icc compiler has the same options as gcc, but "configure" doesn't seem
1757 to know about it. I have put a hack into configure.in that adds in code
1758 to set GCC=yes if CC=icc. This seems to end up at a point in the
1759 generated configure script that is early enough to affect the setting of
1760 compiler options, which is what is needed, but I have no means of testing
1761 whether it really works. (The user who reported this had patched the
1762 generated configure script, which of course I cannot do.)
1763
1764 LATER: After change 22 below (new libtool files), the configure script
1765 seems to know about icc (and also ecc). Therefore, I have commented out
1766 this hack in configure.in.
1767
1768 7. Added support for pkg-config (2 patches were sent in).
1769
1770 8. Negated POSIX character classes that used a combination of internal tables
1771 were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
1772 [[:^ascii]]. Typically, they would match almost any characters. The other
1773 POSIX classes were not broken in this way.
1774
1775 9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
1776 to find the match, as PCRE was deluded into thinking that the match had to
1777 start at the start point or following a newline. The same bug applied to
1778 patterns with negative forward assertions or any backward assertions
1779 preceding ".*" at the start, unless the pattern required a fixed first
1780 character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
1781
1782 10. In UTF-8 mode, when moving forwards in the subject after a failed match
1783 starting at the last subject character, bytes beyond the end of the subject
1784 string were read.
1785
1786 11. Renamed the variable "class" as "classbits" to make life easier for C++
1787 users. (Previously there was a macro definition, but it apparently wasn't
1788 enough.)
1789
1790 12. Added the new field "tables" to the extra data so that tables can be passed
1791 in at exec time, or the internal tables can be re-selected. This allows
1792 a compiled regex to be saved and re-used at a later time by a different
1793 program that might have everything at different addresses.
1794
1795 13. Modified the pcre-config script so that, when run on Solaris, it shows a
1796 -R library as well as a -L library.
1797
1798 14. The debugging options of pcretest (-d on the command line or D on a
1799 pattern) showed incorrect output for anything following an extended class
1800 that contained multibyte characters and which was followed by a quantifier.
1801
1802 15. Added optional support for general category Unicode character properties
1803 via the \p, \P, and \X escapes. Unicode property support implies UTF-8
1804 support. It adds about 90K to the size of the library. The meanings of the
1805 inbuilt class escapes such as \d and \s have NOT been changed.
1806
1807 16. Updated pcredemo.c to include calls to free() to release the memory for the
1808 compiled pattern.
1809
1810 17. The generated file chartables.c was being created in the source directory
1811 instead of in the building directory. This caused the build to fail if the
1812 source directory was different from the building directory, and was
1813 read-only.
1814
1815 18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
1816 file. No doubt somebody will tell me if they don't make sense... Also added
1817 Dan Mooney's comments about building on OpenVMS.
1818
1819 19. Added support for partial matching via the PCRE_PARTIAL option for
1820 pcre_exec() and the \P data escape in pcretest.
1821
1822 20. Extended pcretest with 3 new pattern features:
1823
1824 (i) A pattern option of the form ">rest-of-line" causes pcretest to
1825 write the compiled pattern to the file whose name is "rest-of-line".
1826 This is a straight binary dump of the data, with the saved pointer to
1827 the character tables forced to be NULL. The study data, if any, is
1828 written too. After writing, pcretest reads a new pattern.
1829
1830 (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
1831 compiled pattern from the given file. There must not be any
1832 occurrences of "<" in the file name (pretty unlikely); if there are,
1833 pcretest will instead treat the initial "<" as a pattern delimiter.
1834 After reading in the pattern, pcretest goes on to read data lines as
1835 usual.
1836
1837 (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
1838 and 16-bit fields in a compiled pattern, to simulate a pattern that
1839 was compiled on a host of opposite endianness.
1840
1841 21. The pcre-exec() function can now cope with patterns that were compiled on
1842 hosts of opposite endianness, with this restriction:
1843
1844 As for any compiled expression that is saved and used later, the tables
1845 pointer field cannot be preserved; the extra_data field in the arguments
1846 to pcre_exec() should be used to pass in a tables address if a value
1847 other than the default internal tables were used at compile time.
1848
1849 22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
1850 now diagnosed as an error. Previously, most of the time, a negative number
1851 would have been treated as zero, but if in addition "ovector" was passed as
1852 NULL, a crash could occur.
1853
1854 23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
1855 new versions from the libtool 1.5 distribution (the last one is a copy of
1856 a file called libtool.m4). This seems to have fixed the need to patch
1857 "configure" to support Darwin 1.3 (which I used to do). However, I still
1858 had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
1859 workstation).
1860
1861 24. Changed the PCRE licence to be the more standard "BSD" licence.
1862
1863
1864 Version 4.5 01-Dec-03
1865 ---------------------
1866
1867 1. There has been some re-arrangement of the code for the match() function so
1868 that it can be compiled in a version that does not call itself recursively.
1869 Instead, it keeps those local variables that need separate instances for
1870 each "recursion" in a frame on the heap, and gets/frees frames whenever it
1871 needs to "recurse". Keeping track of where control must go is done by means
1872 of setjmp/longjmp. The whole thing is implemented by a set of macros that
1873 hide most of the details from the main code, and operates only if
1874 NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
1875 "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
1876 operating.
1877
1878 To make it easier for callers to provide specially tailored get/free
1879 functions for this usage, two new functions, pcre_stack_malloc, and
1880 pcre_stack_free, are used. They are always called in strict stacking order,
1881 and the size of block requested is always the same.
1882
1883 The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
1884 PCRE has been compiled to use the stack or the heap for recursion. The
1885 -C option of pcretest uses this to show which version is compiled.
1886
1887 A new data escape \S, is added to pcretest; it causes the amounts of store
1888 obtained and freed by both kinds of malloc/free at match time to be added
1889 to the output.
1890
1891 2. Changed the locale test to use "fr_FR" instead of "fr" because that's
1892 what's available on my current Linux desktop machine.
1893
1894 3. When matching a UTF-8 string, the test for a valid string at the start has
1895 been extended. If start_offset is not zero, PCRE now checks that it points
1896 to a byte that is the start of a UTF-8 character. If not, it returns
1897 PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
1898 this is necessary because there may be backward assertions in the pattern.
1899 When matching the same subject several times, it may save resources to use
1900 PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
1901
1902 4. The code for checking the validity of UTF-8 strings has been tightened so
1903 that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
1904 containing "overlong sequences".
1905
1906 5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
1907 I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
1908 should have been "&", but it just so happened that all the cases this let
1909 through by mistake were picked up later in the function.
1910
1911 6. I had used a variable called "isblank" - this is a C99 function, causing
1912 some compilers to warn. To avoid this, I renamed it (as "blankclass").
1913
1914 7. Cosmetic: (a) only output another newline at the end of pcretest if it is
1915 prompting; (b) run "./pcretest /dev/null" at the start of the test script
1916 so the version is shown; (c) stop "make test" echoing "./RunTest".
1917
1918 8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
1919
1920 9. The prototype for memmove() for systems that don't have it was using
1921 size_t, but the inclusion of the header that defines size_t was later. I've
1922 moved the #includes for the C headers earlier to avoid this.
1923
1924 10. Added some adjustments to the code to make it easier to compiler on certain
1925 special systems:
1926
1927 (a) Some "const" qualifiers were missing.
1928 (b) Added the macro EXPORT before all exported functions; by default this
1929 is defined to be empty.
1930 (c) Changed the dftables auxiliary program (that builds chartables.c) so
1931 that it reads its output file name as an argument instead of writing
1932 to the standard output and assuming this can be redirected.
1933
1934 11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
1935 class containing characters with values greater than 255, PCRE compilation
1936 went into a loop.
1937
1938 12. A recursive reference to a subpattern that was within another subpattern
1939 that had a minimum quantifier of zero caused PCRE to crash. For example,
1940 (x(y(?2))z)? provoked this bug with a subject that got as far as the
1941 recursion. If the recursively-called subpattern itself had a zero repeat,
1942 that was OK.
1943
1944 13. In pcretest, the buffer for reading a data line was set at 30K, but the
1945 buffer into which it was copied (for escape processing) was still set at
1946 1024, so long lines caused crashes.
1947
1948 14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
1949 "internal error: code overflow...". This applied to any character class
1950 that was followed by a possessive quantifier.
1951
1952 15. Modified the Makefile to add libpcre.la as a prerequisite for
1953 libpcreposix.la because I was told this is needed for a parallel build to
1954 work.
1955
1956 16. If a pattern that contained .* following optional items at the start was
1957 studied, the wrong optimizing data was generated, leading to matching
1958 errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
1959 matching string must start with a or b or c. The correct conclusion for
1960 this pattern is that a match can start with any character.
1961
1962
1963 Version 4.4 13-Aug-03
1964 ---------------------
1965
1966 1. In UTF-8 mode, a character class containing characters with values between
1967 127 and 255 was not handled correctly if the compiled pattern was studied.
1968 In fixing this, I have also improved the studying algorithm for such
1969 classes (slightly).
1970
1971 2. Three internal functions had redundant arguments passed to them. Removal
1972 might give a very teeny performance improvement.
1973
1974 3. Documentation bug: the value of the capture_top field in a callout is *one
1975 more than* the number of the hightest numbered captured substring.
1976
1977 4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
1978 in incorrectly linking with a previously installed version. They now link
1979 explicitly with libpcre.la.
1980
1981 5. configure.in no longer needs to recognize Cygwin specially.
1982
1983 6. A problem in pcre.in for Windows platforms is fixed.
1984
1985 7. If a pattern was successfully studied, and the -d (or /D) flag was given to
1986 pcretest, it used to include the size of the study block as part of its
1987 output. Unfortunately, the structure contains a field that has a different
1988 size on different hardware architectures. This meant that the tests that
1989 showed this size failed. As the block is currently always of a fixed size,
1990 this information isn't actually particularly useful in pcretest output, so
1991 I have just removed it.
1992
1993 8. Three pre-processor statements accidentally did not start in column 1.
1994 Sadly, there are *still* compilers around that complain, even though
1995 standard C has not required this for well over a decade. Sigh.
1996
1997 9. In pcretest, the code for checking callouts passed small integers in the
1998 callout_data field, which is a void * field. However, some picky compilers
1999 complained about the casts involved for this on 64-bit systems. Now
2000 pcretest passes the address of the small integer instead, which should get
2001 rid of the warnings.
2002
2003 10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
2004 both compile and run time, and gives an error if an invalid UTF-8 sequence
2005 is found. There is a option for disabling this check in cases where the
2006 string is known to be correct and/or the maximum performance is wanted.
2007
2008 11. In response to a bug report, I changed one line in Makefile.in from
2009
2010 -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
2011 to
2012 -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
2013
2014 to look similar to other lines, but I have no way of telling whether this
2015 is the right thing to do, as I do not use Windows. No doubt I'll get told
2016 if it's wrong...
2017
2018
2019 Version 4.3 21-May-03
2020 ---------------------
2021
2022 1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
2023 Makefile.
2024
2025 2. Some refactoring to improve the quality of the code:
2026
2027 (i) The utf8_table... variables are now declared "const".
2028
2029 (ii) The code for \cx, which used the "case flipping" table to upper case
2030 lower case letters, now just substracts 32. This is ASCII-specific,
2031 but the whole concept of \cx is ASCII-specific, so it seems
2032 reasonable.
2033
2034 (iii) PCRE was using its character types table to recognize decimal and
2035 hexadecimal digits in the pattern. This is silly, because it handles
2036 only 0-9, a-f, and A-F, but the character types table is locale-
2037 specific, which means strange things might happen. A private
2038 table is now used for this - though it costs 256 bytes, a table is
2039 much faster than multiple explicit tests. Of course, the standard
2040 character types table is still used for matching digits in subject
2041 strings against \d.
2042
2043 (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
2044 ending in _t are). So I've renamed it as ESC_tee.
2045
2046 3. The first argument for regexec() in the POSIX wrapper should have been
2047 defined as "const".
2048
2049 4. Changed pcretest to use malloc() for its buffers so that they can be
2050 Electric Fenced for debugging.
2051
2052 5. There were several places in the code where, in UTF-8 mode, PCRE would try
2053 to read one or more bytes before the start of the subject string. Often this
2054 had no effect on PCRE's behaviour, but in some circumstances it could
2055 provoke a segmentation fault.
2056
2057 6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
2058 to try to read one or more bytes before the start of the subject string.
2059
2060 7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
2061 UTF-8 support could misbehave in various ways if the subject string
2062 contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
2063 area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
2064 back over UTF-8 characters.)
2065
2066
2067 Version 4.2 14-Apr-03
2068 ---------------------
2069
2070 1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
2071
2072 2. Changes to the building process, supplied by Ronald Landheer-Cieslak
2073 [ON_WINDOWS]: new variable, "#" on non-Windows platforms
2074 [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
2075 [WIN_PREFIX]: new variable, "cyg" for Cygwin
2076 * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
2077 and BUILD_EXEEXT
2078 Note: automatic setting of the BUILD variables is not yet working
2079 set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
2080 compile-time but not at link-time
2081 [LINK]: use for linking executables only
2082 make different versions for Windows and non-Windows
2083 [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
2084 libraries
2085 [LINK_FOR_BUILD]: new variable
2086 [OBJEXT]: use throughout
2087 [EXEEXT]: use throughout
2088 <winshared>: new target
2089 <wininstall>: new target
2090 <dftables.o>: use native compiler
2091 <dftables>: use native linker
2092 <install>: handle Windows platform correctly
2093 <clean>: ditto
2094 <check>: ditto
2095 copy DLL to top builddir before testing
2096
2097 As part of these changes, -no-undefined was removed again. This was reported
2098 to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
2099 in any case.
2100
2101 3. Some tidies to get rid of compiler warnings:
2102
2103 . In the match_data structure, match_limit was an unsigned long int, whereas
2104 match_call_count was an int. I've made them both unsigned long ints.
2105
2106 . In pcretest the fact that a const uschar * doesn't automatically cast to
2107 a void * provoked a warning.
2108
2109 . Turning on some more compiler warnings threw up some "shadow" variables
2110 and a few more missing casts.
2111
2112 4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
2113 option, a class that contained a single character with a value between 128
2114 and 255 (e.g. /[\xFF]/) caused PCRE to crash.
2115
2116 5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
2117 option, a class that contained several characters, but with at least one
2118 whose value was between 128 and 255 caused PCRE to crash.
2119
2120
2121 Version 4.1 12-Mar-03
2122 ---------------------
2123
2124 1. Compiling with gcc -pedantic found a couple of places where casts were
2125 needed, and a string in dftables.c that was longer than standard compilers are
2126 required to support.
2127
2128 2. Compiling with Sun's compiler found a few more places where the code could
2129 be tidied up in order to avoid warnings.
2130
2131 3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
2132 first of these names is deprecated in the latest Autoconf in favour of the name
2133 CC_FOR_BUILD, because "host" is typically used to mean the system on which the
2134 compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
2135 analogy I have changed it to CFLAGS_FOR_BUILD.
2136
2137 4. Added -no-undefined to the linking command in the Makefile, because this is
2138 apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
2139 linking step for the pcreposix library.
2140
2141 5. PCRE was failing to diagnose the case of two named groups with the same
2142 name.
2143
2144 6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
2145 literal character that is needed in the subject for a match, and scans along to
2146 ensure that it is present before embarking on the full matching process. This
2147 saves time in cases of nested unlimited repeats that are never going to match.
2148 Problem: the scan can take a lot of time if the subject is very long (e.g.
2149 megabytes), thus penalizing straightforward matches. It is now done only if the
2150 amount of subject to be scanned is less than 1000 bytes.
2151
2152 7. A lesser problem with the same optimization is that it was recording the
2153 first character of an anchored pattern as "needed", thus provoking a search
2154 right along the subject, even when the first match of the pattern was going to
2155 fail. The "needed" character is now not set for anchored patterns, unless it
2156 follows something in the pattern that is of non-fixed length. Thus, it still
2157 fulfils its original purpose of finding quick non-matches in cases of nested
2158 unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
2159
2160
2161 Version 4.0 17-Feb-03
2162 ---------------------
2163
2164 1. If a comment in an extended regex that started immediately after a meta-item
2165 extended to the end of string, PCRE compiled incorrect data. This could lead to
2166 all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
2167
2168 2. Moved to autoconf 2.53 and libtool 1.4.2.
2169
2170 3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
2171 the special perltest8 script is no longer needed - all the tests can be run
2172 from a single perltest script.
2173
2174 4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
2175 by \s. It has now been removed in PCRE. This means it isn't recognized as
2176 whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
2177 class [:space:] *does* include VT, thereby creating a mess.
2178
2179 5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
2180 space and tab.
2181
2182 6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
2183 its new features into the main test script, reducing the number of scripts.
2184
2185 7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
2186 were backward compatible, and made the (?i) apply to the whole pattern, as if
2187 /i were given. Now it behaves more logically, and applies the option setting
2188 only to what follows. PCRE has been changed to follow suit. However, if it
2189 finds options settings right at the start of the pattern, it extracts them into
2190 the global options, as before. Thus, they show up in the info data.
2191
2192 8. Added support for the \Q...\E escape sequence. Characters in between are
2193 treated as literals. This is slightly different from Perl in that $ and @ are
2194 also handled as literals inside the quotes. In Perl, they will cause variable
2195 interpolation. Note the following examples:
2196
2197 Pattern PCRE matches Perl matches
2198
2199 \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
2200 \Qabc\$xyz\E abc\$xyz abc\$xyz
2201 \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
2202
2203 For compatibility with Perl, \Q...\E sequences are recognized inside character
2204 classes as well as outside them.
2205
2206 9. Re-organized 3 code statements in pcretest to avoid "overflow in
2207 floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
2208 (size_t) cast to one statement in pcretest and one in pcreposix to avoid
2209 signed/unsigned warnings.
2210
2211 10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
2212 option for pcretest, so I've replaced it by a simple function that does just
2213 that job.
2214
2215 11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
2216 "pcregrep -".
2217
2218 12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
2219 Java package. This provides some syntactic sugar for simple cases of what my
2220 documentation calls "once-only subpatterns". A pattern such as x*+ is the same
2221 as (?>x*). In other words, if what is inside (?>...) is just a single repeated
2222 item, you can use this simplified notation. Note that only makes sense with
2223 greedy quantifiers. Consequently, the use of the possessive quantifier forces
2224 greediness, whatever the setting of the PCRE_UNGREEDY option.
2225
2226 13. A change of greediness default within a pattern was not taking effect at
2227 the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
2228 subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
2229 was abstracted outside.
2230
2231 14. PCRE now supports the \G assertion. It is true when the current matching
2232 position is at the start point of the match. This differs from \A when the
2233 starting offset is non-zero. Used with the /g option of pcretest (or similar
2234 code), it works in the same way as it does for Perl's /g option. If all
2235 alternatives of a regex begin with \G, the expression is anchored to the start
2236 match position, and the "anchored" flag is set in the compiled expression.
2237
2238 15. Some bugs concerning the handling of certain option changes within patterns
2239 have been fixed. These applied to options other than (?ims). For example,
2240 "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
2241 been the other way round. Some of this was related to change 7 above.
2242
2243 16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
2244 features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
2245 and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
2246 POSIX classes only within a class (e.g. /[[:alpha:]]/).
2247
2248 17. Added support for Perl's \C escape. This matches one byte, even in UTF8
2249 mode. Unlike ".", it always matches newline, whatever the setting of
2250 PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
2251 assertions. Perl allows it, but it doesn't (in general) work because it can't
2252 calculate the length of the lookbehind. At least, that's the case for Perl
2253 5.8.0 - I've been told they are going to document that it doesn't work in
2254 future.
2255
2256 18. Added an error diagnosis for escapes that PCRE does not support: these are
2257 \L, \l, \N, \P, \p, \U, \u, and \X.
2258
2259 19. Although correctly diagnosing a missing ']' in a character class, PCRE was
2260 reading past the end of the pattern in cases such as /[abcd/.
2261
2262 20. PCRE was getting more memory than necessary for patterns with classes that
2263 contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
2264
2265 21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
2266 compiling PCRE for use with Virtual Pascal.
2267
2268 22. Small fix to the Makefile to make it work properly if the build is done
2269 outside the source tree.
2270
2271 23. Added a new extension: a condition to go with recursion. If a conditional
2272 subpattern starts with (?(R) the "true" branch is used if recursion has
2273 happened, whereas the "false" branch is used only at the top level.
2274
2275 24. When there was a very long string of literal characters (over 255 bytes
2276 without UTF support, over 250 bytes with UTF support), the computation of how
2277 much memory was required could be incorrect, leading to segfaults or other
2278 strange effects.
2279
2280 25. PCRE was incorrectly assuming anchoring (either to start of subject or to
2281 start of line for a non-DOTALL pattern) when a pattern started with (.*) and
2282 there was a subsequent back reference to those brackets. This meant that, for
2283 example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
2284 possible to check for precisely this case. All we can do is abandon the
2285 optimization if .* occurs inside capturing brackets when there are any back
2286 references whatsoever. (See below for a better fix that came later.)
2287
2288 26. The handling of the optimization for finding the first character of a
2289 non-anchored pattern, and for finding a character that is required later in the
2290 match were failing in some cases. This didn't break the matching; it just
2291 failed to optimize when it could. The way this is done has been re-implemented.
2292
2293 27. Fixed typo in error message for invalid (?R item (it said "(?p").
2294
2295 28. Added a new feature that provides some of the functionality that Perl
2296 provides with (?{...}). The facility is termed a "callout". The way it is done
2297 in PCRE is for the caller to provide an optional function, by setting
2298 pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
2299 global variable. By default it is unset, which disables all calling out. To get
2300 the function called, the regex must include (?C) at appropriate points. This
2301 is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
2302 This provides a means of identifying different callout points. When PCRE
2303 reaches such a point in the regex, if pcre_callout has been set, the external
2304 function is called. It is provided with data in a structure called
2305 pcre_callout_block, which is defined in pcre.h. If the function returns 0,
2306 matching continues; if it returns a non-zero value, the match at the current
2307 point fails. However, backtracking will occur if possible. [This was changed
2308 later and other features added - see item 49 below.]
2309
2310 29. pcretest is upgraded to test the callout functionality. It provides a
2311 callout function that displays information. By default, it shows the start of
2312 the match and the current position in the text. There are some new data escapes
2313 to vary what happens:
2314
2315 \C+ in addition, show current contents of captured substrings
2316 \C- do not supply a callout function
2317 \C!n return 1 when callout number n is reached
2318 \C!n!m return 1 when callout number n is reached for the mth time
2319
2320 30. If pcregrep was called with the -l option and just a single file name, it
2321 output "<stdin>" if a match was found, instead of the file name.
2322
2323 31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
2324 slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
2325 pcre_exec(). This saves a malloc/free per call. The default value of
2326 POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
2327 when configuring.
2328
2329 32. The default maximum size of a compiled pattern is 64K. There have been a
2330 few cases of people hitting this limit. The code now uses macros to handle the
2331 storing of links as offsets within the compiled pattern. It defaults to 2-byte
2332 links, but this can be changed to 3 or 4 bytes by --with-link-size when
2333 configuring. Tests 2 and 5 work only with 2-byte links because they output
2334 debugging information about compiled patterns.
2335
2336 33. Internal code re-arrangements:
2337
2338 (a) Moved the debugging function for printing out a compiled regex into
2339 its own source file (printint.c) and used #include to pull it into
2340 pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
2341 separate copies.
2342
2343 (b) Defined the list of op-code names for debugging as a macro in
2344 internal.h so that it is next to the definition of the opcodes.
2345
2346 (c) Defined a table of op-code lengths for simpler skipping along compiled
2347 code. This is again a macro in internal.h so that it is next to the
2348 definition of the opcodes.
2349
2350 34. Added support for recursive calls to individual subpatterns, along the
2351 lines of Robin Houston's patch (but implemented somewhat differently).
2352
2353 35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
2354 allow it to read and process whole directories in Win32. This code was
2355 contributed by Lionel Fourquaux; it has not been tested by me.
2356
2357 36. Added support for named subpatterns. The Python syntax (?P<name>...) is
2358 used to name a group. Names consist of alphanumerics and underscores, and must
2359 be unique. Back references use the syntax (?P=name) and recursive calls use
2360 (?P>name) which is a PCRE extension to the Python extension. Groups still have
2361 numbers. The function pcre_fullinfo() can be used after compilation to extract
2362 a name/number map. There are three relevant calls:
2363
2364 PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
2365 PCRE_INFO_NAMECOUNT yields the number of entries
2366 PCRE_INFO_NAMETABLE yields a pointer to the map.
2367
2368 The map is a vector of fixed-size entries. The size of each entry depends on
2369 the length of the longest name used. The first two bytes of each entry are the
2370 group number, most significant byte first. There follows the corresponding
2371 name, zero terminated. The names are in alphabetical order.
2372
2373 37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
2374 case instead of 255. Making it the same both with and without UTF-8 support
2375 means that the same test output works with both.
2376
2377 38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
2378 calling malloc() with a zero argument.
2379
2380 39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
2381 optimization. I've improved things by keeping a bitmap of backreferences with
2382 numbers 1-31 so that if .* occurs inside capturing brackets that are not in
2383 fact referenced, the optimization can be applied. It is unlikely that a
2384 relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
2385 the match to follow \n) will appear inside brackets with a number greater than
2386 31, but if it does, any back reference > 31 suppresses the optimization.
2387
2388 40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
2389 of disabling numbered capturing parentheses. Any opening parenthesis that is
2390 not followed by ? behaves as if it were followed by ?: but named parentheses
2391 can still be used for capturing (and they will acquire numbers in the usual
2392 way).
2393
2394 41. Redesigned the return codes from the match() function into yes/no/error so
2395 that errors can be passed back from deep inside the nested calls. A malloc
2396 failure while inside a recursive subpattern call now causes the
2397 PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
2398
2399 42. It is now possible to set a limit on the number of times the match()
2400 function is called in a call to pcre_exec(). This facility makes it possible to
2401 limit the amount of recursion and backtracking, though not in a directly
2402 obvious way, because the match() function is used in a number of different
2403 circumstances. The count starts from zero for each position in the subject
2404 string (for non-anchored patterns). The default limit is, for compatibility, a
2405 large number, namely 10 000 000. You can change this in two ways:
2406
2407 (a) When configuring PCRE before making, you can use --with-match-limit=n
2408 to set a default value for the compiled library.
2409
2410 (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
2411 a different value is set. See 45 below.
2412
2413 If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
2414
2415 43. Added a new function pcre_config(int, void *) to enable run-time extraction
2416 of things that can be changed at compile time. The first argument specifies
2417 what is wanted and the second points to where the information is to be placed.
2418 The current list of available information is:
2419
2420 PCRE_CONFIG_UTF8
2421
2422 The output is an integer that is set to one if UTF-8 support is available;
2423 otherwise it is set to zero.
2424
2425 PCRE_CONFIG_NEWLINE
2426
2427 The output is an integer that it set to the value of the code that is used for
2428 newline. It is either LF (10) or CR (13).
2429
2430 PCRE_CONFIG_LINK_SIZE
2431
2432 The output is an integer that contains the number of bytes used for internal
2433 linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
2434
2435 PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
2436
2437 The output is an integer that contains the threshold above which the POSIX
2438 interface uses malloc() for output vectors. See item 31 above.
2439
2440 PCRE_CONFIG_MATCH_LIMIT
2441
2442 The output is an unsigned integer that contains the default limit of the number
2443 of match() calls in a pcre_exec() execution. See 42 above.
2444
2445 44. pcretest has been upgraded by the addition of the -C option. This causes it
2446 to extract all the available output from the new pcre_config() function, and to
2447 output it. The program then exits immediately.
2448
2449 45. A need has arisen to pass over additional data with calls to pcre_exec() in
2450 order to support additional features. One way would have been to define
2451 pcre_exec2() (for example) with extra arguments, but this would not have been
2452 extensible, and would also have required all calls to the original function to
2453 be mapped to the new one. Instead, I have chosen to extend the mechanism that
2454 is used for passing in "extra" data from pcre_study().
2455
2456 The pcre_extra structure is now exposed and defined in pcre.h. It currently
2457 contains the following fields:
2458
2459 flags a bitmap indicating which of the following fields are set
2460 study_data opaque data from pcre_study()
2461 match_limit a way of specifying a limit on match() calls for a specific
2462 call to pcre_exec()
2463 callout_data data for callouts (see 49 below)
2464
2465 The flag bits are also defined in pcre.h, and are
2466
2467 PCRE_EXTRA_STUDY_DATA
2468 PCRE_EXTRA_MATCH_LIMIT
2469 PCRE_EXTRA_CALLOUT_DATA
2470
2471 The pcre_study() function now returns one of these new pcre_extra blocks, with
2472 the actual study data pointed to by the study_data field, and the
2473 PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
2474 before. That is, this change is entirely upwards-compatible and requires no
2475 change to existing code.
2476
2477 If you want to pass in additional data to pcre_exec(), you can either place it
2478 in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
2479 block.
2480
2481 46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
2482 data string contains the escape sequence \M, pcretest calls pcre_exec() several
2483 times with different match limits, until it finds the minimum value needed for
2484 pcre_exec() to complete. The value is then output. This can be instructive; for
2485 most simple matches the number is quite small, but for pathological cases it
2486 gets very large very quickly.
2487
2488 47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
2489 returns the size of the data block pointed to by the study_data field in a
2490 pcre_extra block, that is, the value that was passed as the argument to
2491 pcre_malloc() when PCRE was getting memory in which to place the information
2492 created by pcre_study(). The fourth argument should point to a size_t variable.
2493 pcretest has been extended so that this information is shown after a successful
2494 pcre_study() call when information about the compiled regex is being displayed.
2495
2496 48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
2497 because what follows is always an absolute path. (Later: it turns out that this
2498 is more than cosmetic for MinGW, because it doesn't like empty path
2499 components.)
2500
2501 49. Some changes have been made to the callout feature (see 28 above):
2502
2503 (i) A callout function now has three choices for what it returns:
2504
2505 0 => success, carry on matching
2506 > 0 => failure at this point, but backtrack if possible
2507 < 0 => serious error, return this value from pcre_exec()
2508
2509 Negative values should normally be chosen from the set of PCRE_ERROR_xxx
2510 values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
2511 "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
2512 use by callout functions. It will never be used by PCRE itself.
2513
2514 (ii) The pcre_extra structure (see 45 above) has a void * field called
2515 callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
2516 pcre_callout_block structure has a field of the same name. The contents of
2517 the field passed in the pcre_extra structure are passed to the callout
2518 function in the corresponding field in the callout block. This makes it
2519 easier to use the same callout-containing regex from multiple threads. For
2520 testing, the pcretest program has a new data escape
2521
2522 \C*n pass the number n (may be negative) as callout_data
2523
2524 If the callout function in pcretest receives a non-zero value as
2525 callout_data, it returns that value.
2526
2527 50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
2528 there were some redundant $(CFLAGS) in commands that are now specified as
2529 $(LINK), which already includes $(CFLAGS).
2530
2531 51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
2532 has been compiled with UTF-8 support *and* pcre_compile() has been compiled
2533 with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
2534 one-byte characters throughout. Note that case-insensitive matching applies
2535 only to characters whose values are less than 256. PCRE doesn't support the
2536 notion of cases for higher-valued characters.
2537
2538 (i) A character class whose characters are all within 0-255 is handled as
2539 a bit map, and the map is inverted for negative classes. Previously, a
2540 character > 255 always failed to match such a class; however it should
2541 match if the class was a negative one (e.g. [^ab]). This has been fixed.
2542
2543 (ii) A negated character class with a single character < 255 is coded as
2544 "not this character" (OP_NOT). This wasn't working properly when the test
2545 character was multibyte, either singly or repeated.
2546
2547 (iii) Repeats of multibyte characters are now handled correctly in UTF-8
2548 mode, for example: \x{100}{2,3}.
2549
2550 (iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
2551 singly or repeated) now correctly test multibyte characters. However,
2552 PCRE doesn't recognize any characters with values greater than 255 as
2553 digits, spaces, or word characters. Such characters always match \D, \S,
2554 and \W, and never match \d, \s, or \w.
2555
2556 (v) Classes may now contain characters and character ranges with values
2557 greater than 255. For example: [ab\x{100}-\x{400}].
2558
2559 (vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
2560 PCRE in UTF-8 mode.
2561
2562 52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
2563 PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
2564 retained for backwards compatibility. (Note that LASTLITERAL is also a byte
2565 value.)
2566
2567 53. The single man page has become too large. I have therefore split it up into
2568 a number of separate man pages. These also give rise to individual HTML pages;
2569 these are now put in a separate directory, and there is an index.html page that
2570 lists them all. Some hyperlinking between the pages has been installed.
2571
2572 54. Added convenience functions for handling named capturing parentheses.
2573
2574 55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
2575 aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
2576 true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
2577 are faulted.
2578
2579 56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
2580 calling configure. These values are used when compiling the dftables.c program
2581 which is run to generate the source of the default character tables. They
2582 default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
2583 you will need to set these values.
2584
2585 57. Updated the building process for Windows DLL, as provided by Fred Cox.
2586
2587
2588 Version 3.9 02-Jan-02
2589 ---------------------
2590
2591 1. A bit of extraneous text had somehow crept into the pcregrep documentation.
2592
2593 2. If --disable-static was given, the building process failed when trying to
2594 build pcretest and pcregrep. (For some reason it was using libtool to compile
2595 them, which is not right, as they aren't part of the library.)
2596
2597
2598 Version 3.8 18-Dec-01
2599 ---------------------
2600
2601 1. The experimental UTF-8 code was completely screwed up. It was packing the
2602 bytes in the wrong order. How dumb can you get?
2603
2604
2605 Version 3.7 29-Oct-01
2606 ---------------------
2607
2608 1. In updating pcretest to check change 1 of version 3.6, I screwed up.
2609 This caused pcretest, when used on the test data, to segfault. Unfortunately,
2610 this didn't happen under Solaris 8, where I normally test things.
2611
2612 2. The Makefile had to be changed to make it work on BSD systems, where 'make'
2613 doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
2614 isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
2615 this fix an hour or so after the initial 3.7 release.)
2616
2617
2618 Version 3.6 23-Oct-01
2619 ---------------------
2620
2621 1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
2622 offsets passed as NULL with zero offset count.
2623
2624 2. The config.guess and config.sub files had not been updated when I moved to
2625 the latest autoconf.
2626
2627
2628 Version 3.5 15-Aug-01
2629 ---------------------
2630
2631 1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
2632 had been forgotten.
2633
2634 2. By using declared but undefined structures, we can avoid using "void"
2635 definitions in pcre.h while keeping the internal definitions of the structures
2636 private.
2637
2638 3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
2639 user point of view, this means that both static and shared libraries are built
2640 by default, but this can be individually controlled. More of the work of
2641 handling this static/shared cases is now inside libtool instead of PCRE's make
2642 file.
2643
2644 4. The pcretest utility is now installed along with pcregrep because it is
2645 useful for users (to test regexs) and by doing this, it automatically gets
2646 relinked by libtool. The documentation has been turned into a man page, so
2647 there are now .1, .txt, and .html versions in /doc.
2648
2649 5. Upgrades to pcregrep:
2650 (i) Added long-form option names like gnu grep.
2651 (ii) Added --help to list all options with an explanatory phrase.
2652 (iii) Added -r, --recursive to recurse into sub-directories.
2653 (iv) Added -f, --file to read patterns from a file.
2654
2655 6. pcre_exec() was referring to its "code" argument before testing that
2656 argument for NULL (and giving an error if it was NULL).
2657
2658 7. Upgraded Makefile.in to allow for compiling in a different directory from
2659 the source directory.
2660
2661 8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
2662 options bits, the pointer it was passed was to an int instead of to an unsigned
2663 long int. This mattered only on 64-bit systems.
2664
2665 9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
2666 generated) instead of pcre.in, which it its source. Also made the same change
2667 in several of the .c files.
2668
2669 10. A new release of gcc defines printf() as a macro, which broke pcretest
2670 because it had an ifdef in the middle of a string argument for printf(). Fixed
2671 by using separate calls to printf().
2672
2673 11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
2674 script, to force use of CR or LF instead of \n in the source. On non-Unix
2675 systems, the value can be set in config.h.
2676
2677 12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
2678 absolute limit. Changed the text of the error message to make this clear, and
2679 likewise updated the man page.
2680
2681 13. The limit of 99 on the number of capturing subpatterns has been removed.
2682 The new limit is 65535, which I hope will not be a "real" limit.
2683
2684
2685 Version 3.4 22-Aug-00
2686 ---------------------
2687
2688 1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
2689
2690 2. Diagnose condition (?(0) as an error instead of crashing on matching.
2691
2692
2693 Version 3.3 01-Aug-00
2694 ---------------------
2695
2696 1. If an octal character was given, but the value was greater than \377, it
2697 was not getting masked to the least significant bits, as documented. This could
2698 lead to crashes in some systems.
2699
2700 2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
2701 the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
2702
2703 3. Added the functions pcre_free_substring() and pcre_free_substring_list().
2704 These just pass their arguments on to (pcre_free)(), but they are provided
2705 because some uses of PCRE bind it to non-C systems that can call its functions,
2706 but cannot call free() or pcre_free() directly.
2707
2708 4. Add "make test" as a synonym for "make check". Corrected some comments in
2709 the Makefile.
2710
2711 5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
2712 Makefile.
2713
2714 6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
2715 command called pgrep for grepping around the active processes.
2716
2717 7. Added the beginnings of support for UTF-8 character strings.
2718
2719 8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
2720 RANLIB to ./ltconfig so that they are used by libtool. I think these are all
2721 the relevant ones. (AR is not passed because ./ltconfig does its own figuring
2722 out for the ar command.)
2723
2724
2725 Version 3.2 12-May-00
2726 ---------------------
2727
2728 This is purely a bug fixing release.
2729
2730 1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
2731 of ZA. This was just one example of several cases that could provoke this bug,
2732 which was introduced by change 9 of version 2.00. The code for breaking
2733 infinite loops after an iteration that matches an empty string was't working
2734 correctly.
2735
2736 2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
2737 when matched against abbab (for example). After matching an empty string, it
2738 wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
2739 caused it to match further down the string than it should.
2740
2741 3. The code contained an inclusion of sys/types.h. It isn't clear why this
2742 was there because it doesn't seem to be needed, and it causes trouble on some
2743 systems, as it is not a Standard C header. It has been removed.
2744
2745 4. Made 4 silly changes to the source to avoid stupid compiler warnings that
2746 were reported on the Macintosh. The changes were from
2747
2748 while ((c = *(++ptr)) != 0 && c != '\n');
2749 to
2750 while ((c = *(++ptr)) != 0 && c != '\n') ;
2751
2752 Totally extraordinary, but if that's what it takes...
2753
2754 5. PCRE is being used in one environment where neither memmove() nor bcopy() is
2755 available. Added HAVE_BCOPY and an autoconf test for it; if neither
2756 HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
2757 assumes the way PCRE uses memmove() (always moving upwards).
2758
2759 6. PCRE is being used in one environment where strchr() is not available. There
2760 was only one use in pcre.c, and writing it out to avoid strchr() probably gives
2761 faster code anyway.
2762
2763
2764 Version 3.1 09-Feb-00
2765 ---------------------
2766
2767 The only change in this release is the fixing of some bugs in Makefile.in for
2768 the "install" target:
2769
2770 (1) It was failing to install pcreposix.h.
2771
2772 (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
2773
2774
2775 Version 3.0 01-Feb-00
2776 ---------------------
2777
2778 1. Add support for the /+ modifier to perltest (to output $` like it does in
2779 pcretest).
2780
2781 2. Add support for the /g modifier to perltest.
2782
2783 3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
2784 matches null strings.
2785
2786 4. Fix perltest so that it doesn't do unwanted things when fed an empty
2787 pattern. Perl treats empty patterns specially - it reuses the most recent
2788 pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
2789 effect.
2790
2791 5. The POSIX interface was broken in that it was just handing over the POSIX
2792 captured string vector to pcre_exec(), but (since release 2.00) PCRE has
2793 required a bigger vector, with some working space on the end. This means that
2794 the POSIX wrapper now has to get and free some memory, and copy the results.
2795
2796 6. Added some simple autoconf support, placing the test data and the
2797 documentation in separate directories, re-organizing some of the
2798 information files, and making it build pcre-config (a GNU standard). Also added
2799 libtool support for building PCRE as a shared library, which is now the
2800 default.
2801
2802 7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
2803 09 are not valid octal constants. Single digits will be used for minor values
2804 less than 10.
2805
2806 8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
2807 existing programs that set these in the POSIX interface can use PCRE without
2808 modification.
2809
2810 9. Added a new function, pcre_fullinfo() with an extensible interface. It can
2811 return all that pcre_info() returns, plus additional data. The pcre_info()
2812 function is retained for compatibility, but is considered to be obsolete.
2813
2814 10. Added experimental recursion feature (?R) to handle one common case that
2815 Perl 5.6 will be able to do with (?p{...}).
2816
2817 11. Added support for POSIX character classes like [:alpha:], which Perl is
2818 adopting.
2819
2820
2821 Version 2.08 31-Aug-99
2822 ----------------------
2823
2824 1. When startoffset was not zero and the pattern began with ".*", PCRE was not
2825 trying to match at the startoffset position, but instead was moving forward to
2826 the next newline as if a previous match had failed.
2827
2828 2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
2829 and could get into a loop if a null string was matched other than at the start
2830 of the subject.
2831
2832 3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
2833 be distinguished at compile time, and for completeness also added PCRE_DATE.
2834
2835 5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
2836 in GnuWin32 environments.
2837
2838
2839 Version 2.07 29-Jul-99
2840 ----------------------
2841
2842 1. The documentation is now supplied in plain text form and HTML as well as in
2843 the form of man page sources.
2844
2845 2. C++ compilers don't like assigning (void *) values to other pointer types.
2846 In particular this affects malloc(). Although there is no problem in Standard
2847 C, I've put in casts to keep C++ compilers happy.
2848
2849 3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
2850 should be (const char *).
2851
2852 4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
2853 be useful for non-Unix systems who don't want to bother with the POSIX stuff.
2854 However, I haven't made this a standard facility. The documentation doesn't
2855 mention it, and the Makefile doesn't support it.
2856
2857 5. The Makefile now contains an "install" target, with editable destinations at
2858 the top of the file. The pcretest program is not installed.
2859
2860 6. pgrep -V now gives the PCRE version number and date.
2861
2862 7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
2863 causing the entire string to be ignored, instead of just the last character.
2864
2865 8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
2866 non-matching string, it can take a very, very long time, even for strings of
2867 quite modest length, because of the nested recursion. PCRE now does better in
2868 some of these cases. It does this by remembering the last required literal
2869 character in the pattern, and pre-searching the subject to ensure it is present
2870 before running the real match. In other words, it applies a heuristic to detect
2871 some types of certain failure quickly, and in the above example, if presented
2872 with a string that has no trailing " it gives "no match" very quickly.
2873
2874 9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
2875 other alternatives are tried instead.
2876
2877
2878 Version 2.06 09-Jun-99
2879 ----------------------
2880
2881 1. Change pcretest's output for amount of store used to show just the code
2882 space, because the remainder (the data block) varies in size between 32-bit and
2883 64-bit systems.
2884
2885 2. Added an extra argument to pcre_exec() to supply an offset in the subject to
2886 start matching at. This allows lookbehinds to work when searching for multiple
2887 occurrences in a string.
2888
2889 3. Added additional options to pcretest for testing multiple occurrences:
2890
2891 /+ outputs the rest of the string that follows a match
2892 /g loops for multiple occurrences, using the new startoffset argument
2893 /G loops for multiple occurrences by passing an incremented pointer
2894
2895 4. PCRE wasn't doing the "first character" optimization for patterns starting
2896 with \b or \B, though it was doing it for other lookbehind assertions. That is,
2897 it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
2898 the letter 'x'. On long subject strings, this gives a significant speed-up.
2899
2900
2901 Version 2.05 21-Apr-99
2902 ----------------------
2903
2904 1. Changed the type of magic_number from int to long int so that it works
2905 properly on 16-bit systems.
2906
2907 2. Fixed a bug which caused patterns starting with .* not to work correctly
2908 when the subject string contained newline characters. PCRE was assuming
2909 anchoring for such patterns in all cases, which is not correct because .* will
2910 not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
2911 DOTALL is set at top level; otherwise it knows that patterns starting with .*
2912 must be retried after every newline in the subject.
2913
2914
2915 Version 2.04 18-Feb-99
2916 ----------------------
2917
2918 1. For parenthesized subpatterns with repeats whose minimum was zero, the
2919 computation of the store needed to hold the pattern was incorrect (too large).
2920 If such patterns were nested a few deep, this could multiply and become a real
2921 problem.
2922
2923 2. Added /M option to pcretest to show the memory requirement of a specific
2924 pattern. Made -m a synonym of -s (which does this globally) for compatibility.
2925
2926 3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
2927 compiled in such a way that the backtracking after subsequent failure was
2928 pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
2929 ((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
2930
2931
2932 Version 2.03 02-Feb-99
2933 ----------------------
2934
2935 1. Fixed typo and small mistake in man page.
2936
2937 2. Added 4th condition (GPL supersedes if conflict) and created separate
2938 LICENCE file containing the conditions.
2939
2940 3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
2941 Perl, that is the internal \ allows the delimiter to be included in the
2942 pattern. Locked out the use of \ as a delimiter. If \ immediately follows
2943 the final delimiter, add \ to the end of the pattern (to test the error).
2944
2945 4. Added the convenience functions for extracting substrings after a successful
2946 match. Updated pcretest to make it able to test these functions.
2947
2948
2949 Version 2.02 14-Jan-99
2950 ----------------------
2951
2952 1. Initialized the working variables associated with each extraction so that
2953 their saving and restoring doesn't refer to uninitialized store.
2954
2955 2. Put dummy code into study.c in order to trick the optimizer of the IBM C
2956 compiler for OS/2 into generating correct code. Apparently IBM isn't going to
2957 fix the problem.
2958
2959 3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
2960 calls, and wasn't printing the correct value for compiling calls. Increased the
2961 default value of LOOPREPEAT, and the number of significant figures in the
2962 times.
2963
2964 4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
2965
2966 5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
2967 a building problem on Windows NT with a FAT file system.
2968
2969
2970 Version 2.01 21-Oct-98
2971 ----------------------
2972
2973 1. Changed the API for pcre_compile() to allow for the provision of a pointer
2974 to character tables built by pcre_maketables() in the current locale. If NULL
2975 is passed, the default tables are used.
2976
2977
2978 Version 2.00 24-Sep-98
2979 ----------------------
2980
2981 1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
2982 it any more.
2983
2984 2. Allow quantification of (?>) groups, and make it work correctly.
2985
2986 3. The first character computation wasn't working for (?>) groups.
2987
2988 4. Correct the implementation of \Z (it is permitted to match on the \n at the
2989 end of the subject) and add 5.005's \z, which really does match only at the
2990 very end of the subject.
2991
2992 5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
2993
2994 6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
2995 DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
2996 localized options. All options to pcre_study() were also removed.
2997
2998 7. Add other new features from 5.005:
2999
3000 $(?<= positive lookbehind
3001 $(?<! negative lookbehind
3002 (?imsx-imsx) added the unsetting capability
3003 such a setting is global if at outer level; local otherwise
3004 (?imsx-imsx:) non-capturing groups with option setting
3005 (?(cond)re|re) conditional pattern matching
3006
3007 A backreference to itself in a repeated group matches the previous
3008 captured string.
3009
3010 8. General tidying up of studying (both automatic and via "study")
3011 consequential on the addition of new assertions.
3012
3013 9. As in 5.005, unlimited repeated groups that could match an empty substring
3014 are no longer faulted at compile time. Instead, the loop is forcibly broken at
3015 runtime if any iteration does actually match an empty substring.
3016
3017 10. Include the RunTest script in the distribution.
3018
3019 11. Added tests from the Perl 5.005_02 distribution. This showed up a few
3020 discrepancies, some of which were old and were also with respect to 5.004. They
3021 have now been fixed.
3022
3023
3024 Version 1.09 28-Apr-98
3025 ----------------------
3026
3027 1. A negated single character class followed by a quantifier with a minimum
3028 value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
3029 program crashes, or just wrong answers. This did not apply to negated classes
3030 containing more than one character, or to minima other than one.
3031
3032
3033 Version 1.08 27-Mar-98
3034 ----------------------
3035
3036 1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
3037
3038 2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
3039 latter must appear before anything that relies on it in the pattern.
3040
3041
3042 Version 1.07 16-Feb-98
3043 ----------------------
3044
3045 1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
3046 repeat of a potentially empty string).
3047
3048
3049 Version 1.06 23-Jan-98
3050 ----------------------
3051
3052 1. Added Markus Oberhumer's little patches for C++.
3053
3054 2. Literal strings longer than 255 characters were broken.
3055
3056
3057 Version 1.05 23-Dec-97
3058 ----------------------
3059
3060 1. Negated character classes containing more than one character were failing if
3061 PCRE_CASELESS was set at run time.
3062
3063
3064 Version 1.04 19-Dec-97
3065 ----------------------
3066
3067 1. Corrected the man page, where some "const" qualifiers had been omitted.
3068
3069 2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
3070 input syntax.
3071
3072 3. Fixed memory leak which occurred when a regex with back references was
3073 matched with an offsets vector that wasn't big enough. The temporary memory
3074 that is used in this case wasn't being freed if the match failed.
3075
3076 4. Tidied pcretest to ensure it frees memory that it gets.
3077
3078 5. Temporary memory was being obtained in the case where the passed offsets
3079 vector was exactly big enough.
3080
3081 6. Corrected definition of offsetof() from change 5 below.
3082
3083 7. I had screwed up change 6 below and broken the rules for the use of
3084 setjmp(). Now fixed.
3085
3086
3087 Version 1.03 18-Dec-97
3088 ----------------------
3089
3090 1. A erroneous regex with a missing opening parenthesis was correctly
3091 diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
3092 on some systems.
3093
3094 2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
3095 it was reported that one broken compiler failed on the former because "code" is
3096 also an independent variable.
3097
3098 3. The erroneous regex a[]b caused an array overrun reference.
3099
3100 4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
3101 fail on data ending with that character. (It was going on too far, and checking
3102 the next character, typically a binary zero.) This was specific to the
3103 optimized code for single-character negative classes.
3104
3105 5. Added a contributed patch from the TIN world which does the following:
3106
3107 + Add an undef for memmove, in case the the system defines a macro for it.
3108
3109 + Add a definition of offsetof(), in case there isn't one. (I don't know
3110 the reason behind this - offsetof() is part of the ANSI standard - but
3111 it does no harm).
3112
3113 + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
3114 most of the places where whitespace preceded '#'. I have given up and
3115 allowed the remaining 2 cases to be at the margin.
3116
3117 + Rename some variables in pcre to eliminate shadowing. This seems very
3118 pedantic, but does no harm, of course.
3119
3120 6. Moved the call to setjmp() into its own function, to get rid of warnings
3121 from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
3122
3123 7. Constructs such as \d{8,} were compiling into the equivalent of
3124 \d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
3125 outcome, but in this particular case used more store than had been allocated,
3126 which caused the bug to be discovered because it threw up an internal error.
3127
3128 8. The debugging code in both pcre and pcretest for outputting the compiled
3129 form of a regex was going wrong in the case of back references followed by
3130 curly-bracketed repeats.
3131
3132
3133 Version 1.02 12-Dec-97
3134 ----------------------
3135
3136 1. Typos in pcre.3 and comments in the source fixed.
3137
3138 2. Applied a contributed patch to get rid of places where it used to remove
3139 'const' from variables, and fixed some signed/unsigned and uninitialized
3140 variable warnings.
3141
3142 3. Added the "runtest" target to Makefile.
3143
3144 4. Set default compiler flag to -O2 rather than just -O.
3145
3146
3147 Version 1.01 19-Nov-97
3148 ----------------------
3149
3150 1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
3151 like /([ab]*)*/, that is, for classes with more than one character in them.
3152
3153 2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
3154 as /((?>a*))*/ (a PCRE_EXTRA facility).
3155
3156
3157 Version 1.00 18-Nov-97
3158 ----------------------
3159
3160 1. Added compile-time macros to support systems such as SunOS4 which don't have
3161 memmove() or strerror() but have other things that can be used instead.
3162
3163 2. Arranged that "make clean" removes the executables.
3164
3165
3166 Version 0.99 27-Oct-97
3167 ----------------------
3168
3169 1. Fixed bug in code for optimizing classes with only one character. It was
3170 initializing a 32-byte map regardless, which could cause it to run off the end
3171 of the memory it had got.
3172
3173 2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
3174
3175
3176 Version 0.98 22-Oct-97
3177 ----------------------
3178
3179 1. Fixed bug in code for handling temporary memory usage when there are more
3180 back references than supplied space in the ovector. This could cause segfaults.
3181
3182
3183 Version 0.97 21-Oct-97
3184 ----------------------
3185
3186 1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
3187
3188 2. Optimized negated single characters not to use a bit map.
3189
3190 3. Brought error texts together as macro definitions; clarified some of them;
3191 fixed one that was wrong - it said "range out of order" when it meant "invalid
3192 escape sequence".
3193
3194 4. Changed some char * arguments to const char *.
3195
3196 5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
3197
3198 6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
3199 pcretest.
3200
3201
3202 Version 0.96 16-Oct-97
3203 ----------------------
3204
3205 1. Added a simple "pgrep" utility to the distribution.
3206
3207 2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
3208 unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
3209 where "ddd" means "one or more decimal digits".
3210
3211 3. Fixed serious bug. If a pattern had a back reference, but the call to
3212 pcre_exec() didn't supply a large enough ovector to record the related
3213 identifying subpattern, the match always failed. PCRE now remembers the number
3214 of the largest back reference, and gets some temporary memory in which to save
3215 the offsets during matching if necessary, in order to ensure that
3216 backreferences always work.
3217
3218 4. Increased the compatibility with Perl in a number of ways:
3219
3220 (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
3221 to request this handling. The option can be set at compile or exec time.
3222
3223 (b) $ matches before a terminating newline by default; an option
3224 PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
3225 mode). The option can be set at compile or exec time.
3226
3227 (c) The handling of \ followed by a digit other than 0 is now supposed to be
3228 the same as Perl's. If the decimal number it represents is less than 10
3229 or there aren't that many previous left capturing parentheses, an octal
3230 escape is read. Inside a character class, it's always an octal escape,
3231 even if it is a single digit.
3232
3233 (d) An escaped but undefined alphabetic character is taken as a literal,
3234 unless PCRE_EXTRA is set. Currently this just reserves the remaining
3235 escapes.
3236
3237 (e) {0} is now permitted. (The previous item is removed from the compiled
3238 pattern).
3239
3240 5. Changed all the names of code files so that the basic parts are no longer
3241 than 10 characters, and abolished the teeny "globals.c" file.
3242
3243 6. Changed the handling of character classes; they are now done with a 32-byte
3244 bit map always.
3245
3246 7. Added the -d and /D options to pcretest to make it possible to look at the
3247 internals of compilation without having to recompile pcre.
3248
3249
3250 Version 0.95 23-Sep-97
3251 ----------------------
3252
3253 1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
3254 \x20 at the start of a run of normal characters. These were being treated as
3255 real characters, instead of the source characters being re-checked.
3256
3257
3258 Version 0.94 18-Sep-97
3259 ----------------------
3260
3261 1. The functions are now thread-safe, with the caveat that the global variables
3262 containing pointers to malloc() and free() or alternative functions are the
3263 same for all threads.
3264
3265 2. Get pcre_study() to generate a bitmap of initial characters for non-
3266 anchored patterns when this is possible, and use it if passed to pcre_exec().
3267
3268
3269 Version 0.93 15-Sep-97
3270 ----------------------
3271
3272 1. /(b)|(:+)/ was computing an incorrect first character.
3273
3274 2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
3275 but not actually doing anything yet.
3276
3277 3. Treat "-" characters in classes that cannot be part of ranges as literals,
3278 as Perl does (e.g. [-az] or [az-]).
3279
3280 4. Set the anchored flag if a branch starts with .* or .*? because that tests
3281 all possible positions.
3282
3283 5. Split up into different modules to avoid including unneeded functions in a
3284 compiled binary. However, compile and exec are still in one module. The "study"
3285 function is split off.
3286
3287 6. The character tables are now in a separate module whose source is generated
3288 by an auxiliary program - but can then be edited by hand if required. There are
3289 now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
3290 toupper() in the code.
3291
3292 7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
3293 make them global. Abolish the function for setting them, as the caller can now
3294 set them directly.
3295
3296
3297 Version 0.92 11-Sep-97
3298 ----------------------
3299
3300 1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
3301 (e.g. /a{1,3}/) was broken (I mis-optimized it).
3302
3303 2. Caseless matching was not working in character classes if the characters in
3304 the pattern were in upper case.
3305
3306 3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
3307
3308 4. Make PCRE_ANCHORED public and accept as a compile option.
3309
3310 5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
3311 PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
3312 pass them.
3313
3314 6. Give an error if bad option bits passed at compile or run time.
3315
3316 7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
3317 pcretest to cause it to pass that flag.
3318
3319 8. Add pcre_info(), to get the number of identifying subpatterns, the stored
3320 options, and the first character, if set.
3321
3322 9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
3323
3324
3325 Version 0.91 10-Sep-97
3326 ----------------------
3327
3328 1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
3329 match the empty string as in /(a*)*/. It was looping and ultimately crashing.
3330
3331 2. PCRE was looping on encountering an indefinitely repeated back reference to
3332 a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
3333 Perl does - treats the match as successful.
3334
3335 ****

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