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Revision 909 - (show annotations)
Sat Feb 4 15:01:47 2012 UTC (9 years, 4 months ago) by ph10
File size: 21796 byte(s)
Final source and document tidies for 8.30.
1 News about PCRE releases
2 ------------------------
4 Release 8.30 04-February-2012
5 -----------------------------
7 Release 8.30 introduces a major new feature: support for 16-bit character
8 strings, compiled as a separate library. There are a few changes to the
9 8-bit library, in addition to some bug fixes.
11 . The pcre_info() function, which has been obsolete for over 10 years, has
12 been removed.
14 . When a compiled pattern was saved to a file and later reloaded on a host
15 with different endianness, PCRE used automatically to swap the bytes in some
16 of the data fields. With the advent of the 16-bit library, where more of this
17 swapping is needed, it is no longer done automatically. Instead, the bad
18 endianness is detected and a specific error is given. The user can then call
19 a new function called pcre_pattern_to_host_byte_order() (or an equivalent
20 16-bit function) to do the swap.
22 . In UTF-8 mode, the values 0xd800 to 0xdfff are not legal Unicode
23 code points and are now faulted. (They are the so-called "surrogates"
24 that are reserved for coding high values in UTF-16.)
27 Release 8.21 12-Dec-2011
28 ------------------------
30 This is almost entirely a bug-fix release. The only new feature is the ability
31 to obtain the size of the memory used by the JIT compiler.
34 Release 8.20 21-Oct-2011
35 ------------------------
37 The main change in this release is the inclusion of Zoltan Herczeg's
38 just-in-time compiler support, which can be accessed by building PCRE with
39 --enable-jit. Large performance benefits can be had in many situations. 8.20
40 also fixes an unfortunate bug that was introduced in 8.13 as well as tidying up
41 a number of infelicities and differences from Perl.
44 Release 8.13 16-Aug-2011
45 ------------------------
47 This is mainly a bug-fix release. There has been a lot of internal refactoring.
48 The Unicode tables have been updated. The only new feature in the library is
49 the passing of *MARK information to callouts. Some additions have been made to
50 pcretest to make testing easier and more comprehensive. There is a new option
51 for pcregrep to adjust its internal buffer size.
54 Release 8.12 15-Jan-2011
55 ------------------------
57 This release fixes some bugs in pcregrep, one of which caused the tests to fail
58 on 64-bit big-endian systems. There are no changes to the code of the library.
61 Release 8.11 10-Dec-2010
62 ------------------------
64 A number of bugs in the library and in pcregrep have been fixed. As always, see
65 ChangeLog for details. The following are the non-bug-fix changes:
67 . Added --match-limit and --recursion-limit to pcregrep.
69 . Added an optional parentheses number to the -o and --only-matching options
70 of pcregrep.
72 . Changed the way PCRE_PARTIAL_HARD affects the matching of $, \z, \Z, \b, and
73 \B.
75 . Added PCRE_ERROR_SHORTUTF8 to make it possible to distinguish between a
76 bad UTF-8 sequence and one that is incomplete when using PCRE_PARTIAL_HARD.
78 . Recognize (*NO_START_OPT) at the start of a pattern to set the PCRE_NO_
79 START_OPTIMIZE option, which is now allowed at compile time
82 Release 8.10 25-Jun-2010
83 ------------------------
85 There are two major additions: support for (*MARK) and friends, and the option
86 PCRE_UCP, which changes the behaviour of \b, \d, \s, and \w (and their
87 opposites) so that they make use of Unicode properties. There are also a number
88 of lesser new features, and several bugs have been fixed. A new option,
89 --line-buffered, has been added to pcregrep, for use when it is connected to
90 pipes.
93 Release 8.02 19-Mar-2010
94 ------------------------
96 Another bug-fix release.
99 Release 8.01 19-Jan-2010
100 ------------------------
102 This is a bug-fix release. Several bugs in the code itself and some bugs and
103 infelicities in the build system have been fixed.
106 Release 8.00 19-Oct-09
107 ----------------------
109 Bugs have been fixed in the library and in pcregrep. There are also some
110 enhancements. Restrictions on patterns used for partial matching have been
111 removed, extra information is given for partial matches, the partial matching
112 process has been improved, and an option to make a partial match override a
113 full match is available. The "study" process has been enhanced by finding a
114 lower bound matching length. Groups with duplicate numbers may now have
115 duplicated names without the use of PCRE_DUPNAMES. However, they may not have
116 different names. The documentation has been revised to reflect these changes.
117 The version number has been expanded to 3 digits as it is clear that the rate
118 of change is not slowing down.
121 Release 7.9 11-Apr-09
122 ---------------------
124 Mostly bugfixes and tidies with just a couple of minor functional additions.
127 Release 7.8 05-Sep-08
128 ---------------------
130 More bug fixes, plus a performance improvement in Unicode character property
131 lookup.
134 Release 7.7 07-May-08
135 ---------------------
137 This is once again mainly a bug-fix release, but there are a couple of new
138 features.
141 Release 7.6 28-Jan-08
142 ---------------------
144 The main reason for having this release so soon after 7.5 is because it fixes a
145 potential buffer overflow problem in pcre_compile() when run in UTF-8 mode. In
146 addition, the CMake configuration files have been brought up to date.
149 Release 7.5 10-Jan-08
150 ---------------------
152 This is mainly a bug-fix release. However the ability to link pcregrep with
153 libz or libbz2 and the ability to link pcretest with libreadline have been
154 added. Also the --line-offsets and --file-offsets options were added to
155 pcregrep.
158 Release 7.4 21-Sep-07
159 ---------------------
161 The only change of specification is the addition of options to control whether
162 \R matches any Unicode line ending (the default) or just CR, LF, and CRLF.
163 Otherwise, the changes are bug fixes and a refactoring to reduce the number of
164 relocations needed in a shared library. There have also been some documentation
165 updates, in particular, some more information about using CMake to build PCRE
166 has been added to the NON-UNIX-USE file.
169 Release 7.3 28-Aug-07
170 ---------------------
172 Most changes are bug fixes. Some that are not:
174 1. There is some support for Perl 5.10's experimental "backtracking control
175 verbs" such as (*PRUNE).
177 2. UTF-8 checking is now as per RFC 3629 instead of RFC 2279; this is more
178 restrictive in the strings it accepts.
180 3. Checking for potential integer overflow has been made more dynamic, and as a
181 consequence there is no longer a hard limit on the size of a subpattern that
182 has a limited repeat count.
184 4. When CRLF is a valid line-ending sequence, pcre_exec() and pcre_dfa_exec()
185 no longer advance by two characters instead of one when an unanchored match
186 fails at CRLF if there are explicit CR or LF matches within the pattern.
187 This gets rid of some anomalous effects that previously occurred.
189 5. Some PCRE-specific settings for varying the newline options at the start of
190 a pattern have been added.
193 Release 7.2 19-Jun-07
194 ---------------------
196 WARNING: saved patterns that were compiled by earlier versions of PCRE must be
197 recompiled for use with 7.2 (necessitated by the addition of \K, \h, \H, \v,
198 and \V).
200 Correction to the notes for 7.1: the note about shared libraries for Windows is
201 wrong. Previously, three libraries were built, but each could function
202 independently. For example, the pcreposix library also included all the
203 functions from the basic pcre library. The change is that the three libraries
204 are no longer independent. They are like the Unix libraries. To use the
205 pcreposix functions, for example, you need to link with both the pcreposix and
206 the basic pcre library.
208 Some more features from Perl 5.10 have been added:
210 (?-n) and (?+n) relative references for recursion and subroutines.
212 (?(-n) and (?(+n) relative references as conditions.
214 \k{name} and \g{name} are synonyms for \k<name>.
216 \K to reset the start of the matched string; for example, (foo)\Kbar
217 matches bar preceded by foo, but only sets bar as the matched string.
219 (?| introduces a group where the capturing parentheses in each alternative
220 start from the same number; for example, (?|(abc)|(xyz)) sets capturing
221 parentheses number 1 in both cases.
223 \h, \H, \v, \V match horizontal and vertical whitespace, respectively.
226 Release 7.1 24-Apr-07
227 ---------------------
229 There is only one new feature in this release: a linebreak setting of
230 PCRE_NEWLINE_ANYCRLF. It is a cut-down version of PCRE_NEWLINE_ANY, which
231 recognizes only CRLF, CR, and LF as linebreaks.
233 A few bugs are fixed (see ChangeLog for details), but the major change is a
234 complete re-implementation of the build system. This now has full Autotools
235 support and so is now "standard" in some sense. It should help with compiling
236 PCRE in a wide variety of environments.
238 NOTE: when building shared libraries for Windows, three dlls are now built,
239 called libpcre, libpcreposix, and libpcrecpp. Previously, everything was
240 included in a single dll.
242 Another important change is that the dftables auxiliary program is no longer
243 compiled and run at "make" time by default. Instead, a default set of character
244 tables (assuming ASCII coding) is used. If you want to use dftables to generate
245 the character tables as previously, add --enable-rebuild-chartables to the
246 "configure" command. You must do this if you are compiling PCRE to run on a
247 system that uses EBCDIC code.
249 There is a discussion about character tables in the README file. The default is
250 not to use dftables so that that there is no problem when cross-compiling.
253 Release 7.0 19-Dec-06
254 ---------------------
256 This release has a new major number because there have been some internal
257 upheavals to facilitate the addition of new optimizations and other facilities,
258 and to make subsequent maintenance and extension easier. Compilation is likely
259 to be a bit slower, but there should be no major effect on runtime performance.
260 Previously compiled patterns are NOT upwards compatible with this release. If
261 you have saved compiled patterns from a previous release, you will have to
262 re-compile them. Important changes that are visible to users are:
264 1. The Unicode property tables have been updated to Unicode 5.0.0, which adds
265 some more scripts.
267 2. The option PCRE_NEWLINE_ANY causes PCRE to recognize any Unicode newline
268 sequence as a newline.
270 3. The \R escape matches a single Unicode newline sequence as a single unit.
272 4. New features that will appear in Perl 5.10 are now in PCRE. These include
273 alternative Perl syntax for named parentheses, and Perl syntax for
274 recursion.
276 5. The C++ wrapper interface has been extended by the addition of a
277 QuoteMeta function and the ability to allow copy construction and
278 assignment.
280 For a complete list of changes, see the ChangeLog file.
283 Release 6.7 04-Jul-06
284 ---------------------
286 The main additions to this release are the ability to use the same name for
287 multiple sets of parentheses, and support for CRLF line endings in both the
288 library and pcregrep (and in pcretest for testing).
290 Thanks to Ian Taylor, the stack usage for many kinds of pattern has been
291 significantly reduced for certain subject strings.
294 Release 6.5 01-Feb-06
295 ---------------------
297 Important changes in this release:
299 1. A number of new features have been added to pcregrep.
301 2. The Unicode property tables have been updated to Unicode 4.1.0, and the
302 supported properties have been extended with script names such as "Arabic",
303 and the derived properties "Any" and "L&". This has necessitated a change to
304 the interal format of compiled patterns. Any saved compiled patterns that
305 use \p or \P must be recompiled.
307 3. The specification of recursion in patterns has been changed so that all
308 recursive subpatterns are automatically treated as atomic groups. Thus, for
309 example, (?R) is treated as if it were (?>(?R)). This is necessary because
310 otherwise there are situations where recursion does not work.
312 See the ChangeLog for a complete list of changes, which include a number of bug
313 fixes and tidies.
316 Release 6.0 07-Jun-05
317 ---------------------
319 The release number has been increased to 6.0 because of the addition of several
320 major new pieces of functionality.
322 A new function, pcre_dfa_exec(), which implements pattern matching using a DFA
323 algorithm, has been added. This has a number of advantages for certain cases,
324 though it does run more slowly, and lacks the ability to capture substrings. On
325 the other hand, it does find all matches, not just the first, and it works
326 better for partial matching. The pcrematching man page discusses the
327 differences.
329 The pcretest program has been enhanced so that it can make use of the new
330 pcre_dfa_exec() matching function and the extra features it provides.
332 The distribution now includes a C++ wrapper library. This is built
333 automatically if a C++ compiler is found. The pcrecpp man page discusses this
334 interface.
336 The code itself has been re-organized into many more files, one for each
337 function, so it no longer requires everything to be linked in when static
338 linkage is used. As a consequence, some internal functions have had to have
339 their names exposed. These functions all have names starting with _pcre_. They
340 are undocumented, and are not intended for use by outside callers.
342 The pcregrep program has been enhanced with new functionality such as
343 multiline-matching and options for output more matching context. See the
344 ChangeLog for a complete list of changes to the library and the utility
345 programs.
348 Release 5.0 13-Sep-04
349 ---------------------
351 The licence under which PCRE is released has been changed to the more
352 conventional "BSD" licence.
354 In the code, some bugs have been fixed, and there are also some major changes
355 in this release (which is why I've increased the number to 5.0). Some changes
356 are internal rearrangements, and some provide a number of new facilities. The
357 new features are:
359 1. There's an "automatic callout" feature that inserts callouts before every
360 item in the regex, and there's a new callout field that gives the position
361 in the pattern - useful for debugging and tracing.
363 2. The extra_data structure can now be used to pass in a set of character
364 tables at exec time. This is useful if compiled regex are saved and re-used
365 at a later time when the tables may not be at the same address. If the
366 default internal tables are used, the pointer saved with the compiled
367 pattern is now set to NULL, which means that you don't need to do anything
368 special unless you are using custom tables.
370 3. It is possible, with some restrictions on the content of the regex, to
371 request "partial" matching. A special return code is given if all of the
372 subject string matched part of the regex. This could be useful for testing
373 an input field as it is being typed.
375 4. There is now some optional support for Unicode character properties, which
376 means that the patterns items such as \p{Lu} and \X can now be used. Only
377 the general category properties are supported. If PCRE is compiled with this
378 support, an additional 90K data structure is include, which increases the
379 size of the library dramatically.
381 5. There is support for saving compiled patterns and re-using them later.
383 6. There is support for running regular expressions that were compiled on a
384 different host with the opposite endianness.
386 7. The pcretest program has been extended to accommodate the new features.
388 The main internal rearrangement is that sequences of literal characters are no
389 longer handled as strings. Instead, each character is handled on its own. This
390 makes some UTF-8 handling easier, and makes the support of partial matching
391 possible. Compiled patterns containing long literal strings will be larger as a
392 result of this change; I hope that performance will not be much affected.
395 Release 4.5 01-Dec-03
396 ---------------------
398 Again mainly a bug-fix and tidying release, with only a couple of new features:
400 1. It's possible now to compile PCRE so that it does not use recursive
401 function calls when matching. Instead it gets memory from the heap. This slows
402 things down, but may be necessary on systems with limited stacks.
404 2. UTF-8 string checking has been tightened to reject overlong sequences and to
405 check that a starting offset points to the start of a character. Failure of the
406 latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET.
408 3. PCRE can now be compiled for systems that use EBCDIC code.
411 Release 4.4 21-Aug-03
412 ---------------------
414 This is mainly a bug-fix and tidying release. The only new feature is that PCRE
415 checks UTF-8 strings for validity by default. There is an option to suppress
416 this, just in case anybody wants that teeny extra bit of performance.
419 Releases 4.1 - 4.3
420 ------------------
422 Sorry, I forgot about updating the NEWS file for these releases. Please take a
423 look at ChangeLog.
426 Release 4.0 17-Feb-03
427 ---------------------
429 There have been a lot of changes for the 4.0 release, adding additional
430 functionality and mending bugs. Below is a list of the highlights of the new
431 functionality. For full details of these features, please consult the
432 documentation. For a complete list of changes, see the ChangeLog file.
434 1. Support for Perl's \Q...\E escapes.
436 2. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java
437 package. They provide some syntactic sugar for simple cases of "atomic
438 grouping".
440 3. Support for the \G assertion. It is true when the current matching position
441 is at the start point of the match.
443 4. A new feature that provides some of the functionality that Perl provides
444 with (?{...}). The facility is termed a "callout". The way it is done in PCRE
445 is for the caller to provide an optional function, by setting pcre_callout to
446 its entry point. To get the function called, the regex must include (?C) at
447 appropriate points.
449 5. Support for recursive calls to individual subpatterns. This makes it really
450 easy to get totally confused.
452 6. Support for named subpatterns. The Python syntax (?P<name>...) is used to
453 name a group.
455 7. Several extensions to UTF-8 support; it is now fairly complete. There is an
456 option for pcregrep to make it operate in UTF-8 mode.
458 8. The single man page has been split into a number of separate man pages.
459 These also give rise to individual HTML pages which are put in a separate
460 directory. There is an index.html page that lists them all. Some hyperlinking
461 between the pages has been installed.
464 Release 3.5 15-Aug-01
465 ---------------------
467 1. The configuring system has been upgraded to use later versions of autoconf
468 and libtool. By default it builds both a shared and a static library if the OS
469 supports it. You can use --disable-shared or --disable-static on the configure
470 command if you want only one of them.
472 2. The pcretest utility is now installed along with pcregrep because it is
473 useful for users (to test regexs) and by doing this, it automatically gets
474 relinked by libtool. The documentation has been turned into a man page, so
475 there are now .1, .txt, and .html versions in /doc.
477 3. Upgrades to pcregrep:
478 (i) Added long-form option names like gnu grep.
479 (ii) Added --help to list all options with an explanatory phrase.
480 (iii) Added -r, --recursive to recurse into sub-directories.
481 (iv) Added -f, --file to read patterns from a file.
483 4. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
484 script, to force use of CR or LF instead of \n in the source. On non-Unix
485 systems, the value can be set in config.h.
487 5. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
488 absolute limit. Changed the text of the error message to make this clear, and
489 likewise updated the man page.
491 6. The limit of 99 on the number of capturing subpatterns has been removed.
492 The new limit is 65535, which I hope will not be a "real" limit.
495 Release 3.3 01-Aug-00
496 ---------------------
498 There is some support for UTF-8 character strings. This is incomplete and
499 experimental. The documentation describes what is and what is not implemented.
500 Otherwise, this is just a bug-fixing release.
503 Release 3.0 01-Feb-00
504 ---------------------
506 1. A "configure" script is now used to configure PCRE for Unix systems. It
507 builds a Makefile, a config.h file, and the pcre-config script.
509 2. PCRE is built as a shared library by default.
511 3. There is support for POSIX classes such as [:alpha:].
513 5. There is an experimental recursion feature.
515 ----------------------------------------------------------------------------
518 Please note that there has been a change in the API such that a larger
519 ovector is required at matching time, to provide some additional workspace.
520 The new man page has details. This change was necessary in order to support
521 some of the new functionality in Perl 5.005.
525 Another (I hope this is the last!) change has been made to the API for the
526 pcre_compile() function. An additional argument has been added to make it
527 possible to pass over a pointer to character tables built in the current
528 locale by pcre_maketables(). To use the default tables, this new arguement
529 should be passed as NULL.
533 Yet another (and again I hope this really is the last) change has been made
534 to the API for the pcre_exec() function. An additional argument has been
535 added to make it possible to start the match other than at the start of the
536 subject string. This is important if there are lookbehinds. The new man
537 page has the details, but you just want to convert existing programs, all
538 you need to do is to stick in a new fifth argument to pcre_exec(), with a
539 value of zero. For example, change
541 pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize)
542 to
543 pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize)
545 ****


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