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Tidies for 7.6-RC1 test release.

1 nigel 41 News about PCRE releases
2     ------------------------
3    
4 ph10 309 Release 7.6 21-Jan-08
5     ---------------------
6    
7     The main reason for having this release so soon after 7.5 is because it fixes a
8     potential buffer overflow problem in pcre_compile() when run in UTF-8 mode. In
9     addition, the CMake configuration files have been brought up to date.
10    
11    
12 ph10 298 Release 7.5 10-Jan-08
13 ph10 289 ---------------------
14 ph10 122
15 ph10 289 This is mainly a bug-fix release. However the ability to link pcregrep with
16     libz or libbz2 and the ability to link pcretest with libreadline have been
17     added. Also the --line-offsets and --file-offsets options were added to
18     pcregrep.
19    
20    
21 ph10 260 Release 7.4 21-Sep-07
22 ph10 242 ---------------------
23    
24 ph10 243 The only change of specification is the addition of options to control whether
25 ph10 242 \R matches any Unicode line ending (the default) or just CR, LF, and CRLF.
26 ph10 243 Otherwise, the changes are bug fixes and a refactoring to reduce the number of
27 ph10 261 relocations needed in a shared library. There have also been some documentation
28     updates, in particular, some more information about using CMake to build PCRE
29     has been added to the NON-UNIX-USE file.
30 ph10 242
31    
32 ph10 228 Release 7.3 28-Aug-07
33 ph10 212 ---------------------
34    
35     Most changes are bug fixes. Some that are not:
36    
37     1. There is some support for Perl 5.10's experimental "backtracking control
38     verbs" such as (*PRUNE).
39    
40     2. UTF-8 checking is now as per RFC 3629 instead of RFC 2279; this is more
41     restrictive in the strings it accepts.
42    
43     3. Checking for potential integer overflow has been made more dynamic, and as a
44     consequence there is no longer a hard limit on the size of a subpattern that
45     has a limited repeat count.
46 ph10 227
47     4. When CRLF is a valid line-ending sequence, pcre_exec() and pcre_dfa_exec()
48     no longer advance by two characters instead of one when an unanchored match
49     fails at CRLF if there are explicit CR or LF matches within the pattern.
50 ph10 226 This gets rid of some anomalous effects that previously occurred.
51 ph10 212
52 ph10 227 5. Some PCRE-specific settings for varying the newline options at the start of
53     a pattern have been added.
54 ph10 212
55 ph10 227
56 ph10 184 Release 7.2 19-Jun-07
57 ph10 157 ---------------------
58    
59 ph10 172 WARNING: saved patterns that were compiled by earlier versions of PCRE must be
60 ph10 181 recompiled for use with 7.2 (necessitated by the addition of \K, \h, \H, \v,
61     and \V).
62 ph10 168
63 ph10 159 Correction to the notes for 7.1: the note about shared libraries for Windows is
64     wrong. Previously, three libraries were built, but each could function
65     independently. For example, the pcreposix library also included all the
66     functions from the basic pcre library. The change is that the three libraries
67     are no longer independent. They are like the Unix libraries. To use the
68     pcreposix functions, for example, you need to link with both the pcreposix and
69 ph10 157 the basic pcre library.
70    
71 ph10 166 Some more features from Perl 5.10 have been added:
72 ph10 157
73 ph10 166 (?-n) and (?+n) relative references for recursion and subroutines.
74 ph10 172
75     (?(-n) and (?(+n) relative references as conditions.
76 ph10 182
77 ph10 181 \k{name} and \g{name} are synonyms for \k<name>.
78 ph10 172
79 ph10 168 \K to reset the start of the matched string; for example, (foo)\Kbar
80 ph10 175 matches bar preceded by foo, but only sets bar as the matched string.
81 ph10 182
82     (?| introduces a group where the capturing parentheses in each alternative
83     start from the same number; for example, (?|(abc)|(xyz)) sets capturing
84 ph10 175 parentheses number 1 in both cases.
85 ph10 166
86 ph10 182 \h, \H, \v, \V match horizontal and vertical whitespace, respectively.
87 ph10 166
88 ph10 182
89 ph10 155 Release 7.1 24-Apr-07
90 nigel 93 ---------------------
91    
92 ph10 155 There is only one new feature in this release: a linebreak setting of
93     PCRE_NEWLINE_ANYCRLF. It is a cut-down version of PCRE_NEWLINE_ANY, which
94     recognizes only CRLF, CR, and LF as linebreaks.
95 ph10 122
96 ph10 155 A few bugs are fixed (see ChangeLog for details), but the major change is a
97     complete re-implementation of the build system. This now has full Autotools
98     support and so is now "standard" in some sense. It should help with compiling
99     PCRE in a wide variety of environments.
100    
101 ph10 146 NOTE: when building shared libraries for Windows, three dlls are now built,
102     called libpcre, libpcreposix, and libpcrecpp. Previously, everything was
103     included in a single dll.
104    
105     Another important change is that the dftables auxiliary program is no longer
106 ph10 128 compiled and run at "make" time by default. Instead, a default set of character
107     tables (assuming ASCII coding) is used. If you want to use dftables to generate
108     the character tables as previously, add --enable-rebuild-chartables to the
109     "configure" command. You must do this if you are compiling PCRE to run on a
110     system that uses EBCDIC code.
111 ph10 122
112 ph10 128 There is a discussion about character tables in the README file. The default is
113     not to use dftables so that that there is no problem when cross-compiling.
114    
115    
116 ph10 122 Release 7.0 19-Dec-06
117     ---------------------
118    
119 nigel 93 This release has a new major number because there have been some internal
120     upheavals to facilitate the addition of new optimizations and other facilities,
121     and to make subsequent maintenance and extension easier. Compilation is likely
122     to be a bit slower, but there should be no major effect on runtime performance.
123     Previously compiled patterns are NOT upwards compatible with this release. If
124     you have saved compiled patterns from a previous release, you will have to
125     re-compile them. Important changes that are visible to users are:
126    
127     1. The Unicode property tables have been updated to Unicode 5.0.0, which adds
128     some more scripts.
129    
130     2. The option PCRE_NEWLINE_ANY causes PCRE to recognize any Unicode newline
131     sequence as a newline.
132    
133     3. The \R escape matches a single Unicode newline sequence as a single unit.
134    
135     4. New features that will appear in Perl 5.10 are now in PCRE. These include
136     alternative Perl syntax for named parentheses, and Perl syntax for
137     recursion.
138    
139     5. The C++ wrapper interface has been extended by the addition of a
140     QuoteMeta function and the ability to allow copy construction and
141     assignment.
142    
143     For a complete list of changes, see the ChangeLog file.
144    
145    
146 nigel 91 Release 6.7 04-Jul-06
147     ---------------------
148    
149     The main additions to this release are the ability to use the same name for
150     multiple sets of parentheses, and support for CRLF line endings in both the
151     library and pcregrep (and in pcretest for testing).
152    
153     Thanks to Ian Taylor, the stack usage for many kinds of pattern has been
154     significantly reduced for certain subject strings.
155    
156    
157 nigel 87 Release 6.5 01-Feb-06
158     ---------------------
159    
160     Important changes in this release:
161    
162     1. A number of new features have been added to pcregrep.
163    
164     2. The Unicode property tables have been updated to Unicode 4.1.0, and the
165     supported properties have been extended with script names such as "Arabic",
166     and the derived properties "Any" and "L&". This has necessitated a change to
167     the interal format of compiled patterns. Any saved compiled patterns that
168     use \p or \P must be recompiled.
169    
170     3. The specification of recursion in patterns has been changed so that all
171     recursive subpatterns are automatically treated as atomic groups. Thus, for
172     example, (?R) is treated as if it were (?>(?R)). This is necessary because
173     otherwise there are situations where recursion does not work.
174    
175     See the ChangeLog for a complete list of changes, which include a number of bug
176     fixes and tidies.
177    
178    
179 nigel 77 Release 6.0 07-Jun-05
180     ---------------------
181    
182     The release number has been increased to 6.0 because of the addition of several
183     major new pieces of functionality.
184    
185     A new function, pcre_dfa_exec(), which implements pattern matching using a DFA
186     algorithm, has been added. This has a number of advantages for certain cases,
187     though it does run more slowly, and lacks the ability to capture substrings. On
188     the other hand, it does find all matches, not just the first, and it works
189     better for partial matching. The pcrematching man page discusses the
190     differences.
191    
192     The pcretest program has been enhanced so that it can make use of the new
193     pcre_dfa_exec() matching function and the extra features it provides.
194    
195     The distribution now includes a C++ wrapper library. This is built
196     automatically if a C++ compiler is found. The pcrecpp man page discusses this
197     interface.
198    
199     The code itself has been re-organized into many more files, one for each
200     function, so it no longer requires everything to be linked in when static
201     linkage is used. As a consequence, some internal functions have had to have
202     their names exposed. These functions all have names starting with _pcre_. They
203     are undocumented, and are not intended for use by outside callers.
204    
205     The pcregrep program has been enhanced with new functionality such as
206     multiline-matching and options for output more matching context. See the
207     ChangeLog for a complete list of changes to the library and the utility
208     programs.
209    
210    
211 nigel 75 Release 5.0 13-Sep-04
212     ---------------------
213    
214     The licence under which PCRE is released has been changed to the more
215     conventional "BSD" licence.
216    
217     In the code, some bugs have been fixed, and there are also some major changes
218     in this release (which is why I've increased the number to 5.0). Some changes
219     are internal rearrangements, and some provide a number of new facilities. The
220     new features are:
221    
222     1. There's an "automatic callout" feature that inserts callouts before every
223     item in the regex, and there's a new callout field that gives the position
224     in the pattern - useful for debugging and tracing.
225    
226     2. The extra_data structure can now be used to pass in a set of character
227     tables at exec time. This is useful if compiled regex are saved and re-used
228     at a later time when the tables may not be at the same address. If the
229     default internal tables are used, the pointer saved with the compiled
230     pattern is now set to NULL, which means that you don't need to do anything
231     special unless you are using custom tables.
232    
233     3. It is possible, with some restrictions on the content of the regex, to
234     request "partial" matching. A special return code is given if all of the
235     subject string matched part of the regex. This could be useful for testing
236     an input field as it is being typed.
237    
238     4. There is now some optional support for Unicode character properties, which
239     means that the patterns items such as \p{Lu} and \X can now be used. Only
240     the general category properties are supported. If PCRE is compiled with this
241     support, an additional 90K data structure is include, which increases the
242     size of the library dramatically.
243    
244     5. There is support for saving compiled patterns and re-using them later.
245    
246     6. There is support for running regular expressions that were compiled on a
247     different host with the opposite endianness.
248    
249     7. The pcretest program has been extended to accommodate the new features.
250    
251     The main internal rearrangement is that sequences of literal characters are no
252     longer handled as strings. Instead, each character is handled on its own. This
253     makes some UTF-8 handling easier, and makes the support of partial matching
254     possible. Compiled patterns containing long literal strings will be larger as a
255     result of this change; I hope that performance will not be much affected.
256    
257    
258 nigel 73 Release 4.5 01-Dec-03
259     ---------------------
260    
261     Again mainly a bug-fix and tidying release, with only a couple of new features:
262    
263     1. It's possible now to compile PCRE so that it does not use recursive
264     function calls when matching. Instead it gets memory from the heap. This slows
265     things down, but may be necessary on systems with limited stacks.
266    
267     2. UTF-8 string checking has been tightened to reject overlong sequences and to
268     check that a starting offset points to the start of a character. Failure of the
269     latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET.
270    
271     3. PCRE can now be compiled for systems that use EBCDIC code.
272    
273    
274 nigel 71 Release 4.4 21-Aug-03
275     ---------------------
276    
277     This is mainly a bug-fix and tidying release. The only new feature is that PCRE
278     checks UTF-8 strings for validity by default. There is an option to suppress
279     this, just in case anybody wants that teeny extra bit of performance.
280    
281    
282     Releases 4.1 - 4.3
283     ------------------
284    
285     Sorry, I forgot about updating the NEWS file for these releases. Please take a
286     look at ChangeLog.
287    
288    
289 nigel 63 Release 4.0 17-Feb-03
290     ---------------------
291    
292     There have been a lot of changes for the 4.0 release, adding additional
293     functionality and mending bugs. Below is a list of the highlights of the new
294     functionality. For full details of these features, please consult the
295     documentation. For a complete list of changes, see the ChangeLog file.
296    
297     1. Support for Perl's \Q...\E escapes.
298    
299     2. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java
300     package. They provide some syntactic sugar for simple cases of "atomic
301     grouping".
302    
303     3. Support for the \G assertion. It is true when the current matching position
304     is at the start point of the match.
305    
306     4. A new feature that provides some of the functionality that Perl provides
307     with (?{...}). The facility is termed a "callout". The way it is done in PCRE
308     is for the caller to provide an optional function, by setting pcre_callout to
309     its entry point. To get the function called, the regex must include (?C) at
310     appropriate points.
311    
312     5. Support for recursive calls to individual subpatterns. This makes it really
313     easy to get totally confused.
314    
315     6. Support for named subpatterns. The Python syntax (?P<name>...) is used to
316     name a group.
317    
318     7. Several extensions to UTF-8 support; it is now fairly complete. There is an
319     option for pcregrep to make it operate in UTF-8 mode.
320    
321     8. The single man page has been split into a number of separate man pages.
322     These also give rise to individual HTML pages which are put in a separate
323     directory. There is an index.html page that lists them all. Some hyperlinking
324     between the pages has been installed.
325    
326    
327 nigel 53 Release 3.5 15-Aug-01
328     ---------------------
329    
330     1. The configuring system has been upgraded to use later versions of autoconf
331     and libtool. By default it builds both a shared and a static library if the OS
332     supports it. You can use --disable-shared or --disable-static on the configure
333     command if you want only one of them.
334    
335     2. The pcretest utility is now installed along with pcregrep because it is
336     useful for users (to test regexs) and by doing this, it automatically gets
337     relinked by libtool. The documentation has been turned into a man page, so
338     there are now .1, .txt, and .html versions in /doc.
339    
340     3. Upgrades to pcregrep:
341     (i) Added long-form option names like gnu grep.
342     (ii) Added --help to list all options with an explanatory phrase.
343     (iii) Added -r, --recursive to recurse into sub-directories.
344     (iv) Added -f, --file to read patterns from a file.
345    
346     4. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
347     script, to force use of CR or LF instead of \n in the source. On non-Unix
348     systems, the value can be set in config.h.
349    
350     5. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
351     absolute limit. Changed the text of the error message to make this clear, and
352     likewise updated the man page.
353    
354     6. The limit of 99 on the number of capturing subpatterns has been removed.
355     The new limit is 65535, which I hope will not be a "real" limit.
356    
357    
358 nigel 49 Release 3.3 01-Aug-00
359     ---------------------
360    
361     There is some support for UTF-8 character strings. This is incomplete and
362     experimental. The documentation describes what is and what is not implemented.
363     Otherwise, this is just a bug-fixing release.
364    
365    
366 nigel 43 Release 3.0 01-Feb-00
367     ---------------------
368 nigel 41
369 nigel 43 1. A "configure" script is now used to configure PCRE for Unix systems. It
370     builds a Makefile, a config.h file, and the pcre-config script.
371    
372     2. PCRE is built as a shared library by default.
373    
374     3. There is support for POSIX classes such as [:alpha:].
375    
376     5. There is an experimental recursion feature.
377    
378 nigel 41 ----------------------------------------------------------------------------
379     IMPORTANT FOR THOSE UPGRADING FROM VERSIONS BEFORE 2.00
380    
381     Please note that there has been a change in the API such that a larger
382     ovector is required at matching time, to provide some additional workspace.
383     The new man page has details. This change was necessary in order to support
384     some of the new functionality in Perl 5.005.
385    
386     IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.00
387    
388     Another (I hope this is the last!) change has been made to the API for the
389     pcre_compile() function. An additional argument has been added to make it
390     possible to pass over a pointer to character tables built in the current
391     locale by pcre_maketables(). To use the default tables, this new arguement
392     should be passed as NULL.
393    
394     IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.05
395    
396     Yet another (and again I hope this really is the last) change has been made
397     to the API for the pcre_exec() function. An additional argument has been
398     added to make it possible to start the match other than at the start of the
399     subject string. This is important if there are lookbehinds. The new man
400     page has the details, but you just want to convert existing programs, all
401     you need to do is to stick in a new fifth argument to pcre_exec(), with a
402     value of zero. For example, change
403    
404     pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize)
405     to
406     pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize)
407    
408     ****

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