libraries/spcre/libpcre/pcre/NEWS
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     1 News about PCRE releases
       
     2 ------------------------
       
     3 
       
     4 
       
     5 Release 7.8 05-Sep-08
       
     6 ---------------------
       
     7 
       
     8 More bug fixes, plus a performance improvement in Unicode character property
       
     9 lookup.
       
    10 
       
    11 
       
    12 Release 7.7 07-May-08
       
    13 ---------------------
       
    14 
       
    15 This is once again mainly a bug-fix release, but there are a couple of new
       
    16 features.
       
    17 
       
    18 
       
    19 Release 7.6 28-Jan-08
       
    20 ---------------------
       
    21 
       
    22 The main reason for having this release so soon after 7.5 is because it fixes a
       
    23 potential buffer overflow problem in pcre_compile() when run in UTF-8 mode. In
       
    24 addition, the CMake configuration files have been brought up to date.
       
    25 
       
    26 
       
    27 Release 7.5 10-Jan-08
       
    28 ---------------------
       
    29 
       
    30 This is mainly a bug-fix release. However the ability to link pcregrep with
       
    31 libz or libbz2 and the ability to link pcretest with libreadline have been
       
    32 added. Also the --line-offsets and --file-offsets options were added to
       
    33 pcregrep.
       
    34 
       
    35 
       
    36 Release 7.4 21-Sep-07
       
    37 ---------------------
       
    38 
       
    39 The only change of specification is the addition of options to control whether
       
    40 \R matches any Unicode line ending (the default) or just CR, LF, and CRLF.
       
    41 Otherwise, the changes are bug fixes and a refactoring to reduce the number of
       
    42 relocations needed in a shared library. There have also been some documentation
       
    43 updates, in particular, some more information about using CMake to build PCRE
       
    44 has been added to the NON-UNIX-USE file.
       
    45 
       
    46 
       
    47 Release 7.3 28-Aug-07
       
    48 ---------------------
       
    49 
       
    50 Most changes are bug fixes. Some that are not:
       
    51 
       
    52 1. There is some support for Perl 5.10's experimental "backtracking control
       
    53    verbs" such as (*PRUNE).
       
    54 
       
    55 2. UTF-8 checking is now as per RFC 3629 instead of RFC 2279; this is more
       
    56    restrictive in the strings it accepts.
       
    57 
       
    58 3. Checking for potential integer overflow has been made more dynamic, and as a
       
    59    consequence there is no longer a hard limit on the size of a subpattern that
       
    60    has a limited repeat count.
       
    61 
       
    62 4. When CRLF is a valid line-ending sequence, pcre_exec() and pcre_dfa_exec()
       
    63    no longer advance by two characters instead of one when an unanchored match
       
    64    fails at CRLF if there are explicit CR or LF matches within the pattern.
       
    65    This gets rid of some anomalous effects that previously occurred.
       
    66 
       
    67 5. Some PCRE-specific settings for varying the newline options at the start of
       
    68    a pattern have been added.
       
    69 
       
    70 
       
    71 Release 7.2 19-Jun-07
       
    72 ---------------------
       
    73 
       
    74 WARNING: saved patterns that were compiled by earlier versions of PCRE must be
       
    75 recompiled for use with 7.2 (necessitated by the addition of \K, \h, \H, \v,
       
    76 and \V).
       
    77 
       
    78 Correction to the notes for 7.1: the note about shared libraries for Windows is
       
    79 wrong. Previously, three libraries were built, but each could function
       
    80 independently. For example, the pcreposix library also included all the
       
    81 functions from the basic pcre library. The change is that the three libraries
       
    82 are no longer independent. They are like the Unix libraries. To use the
       
    83 pcreposix functions, for example, you need to link with both the pcreposix and
       
    84 the basic pcre library.
       
    85 
       
    86 Some more features from Perl 5.10 have been added:
       
    87 
       
    88   (?-n) and (?+n) relative references for recursion and subroutines.
       
    89 
       
    90   (?(-n) and (?(+n) relative references as conditions.
       
    91 
       
    92   \k{name} and \g{name} are synonyms for \k<name>.
       
    93 
       
    94   \K to reset the start of the matched string; for example, (foo)\Kbar
       
    95   matches bar preceded by foo, but only sets bar as the matched string.
       
    96 
       
    97   (?| introduces a group where the capturing parentheses in each alternative
       
    98   start from the same number; for example, (?|(abc)|(xyz)) sets capturing
       
    99   parentheses number 1 in both cases.
       
   100 
       
   101   \h, \H, \v, \V match horizontal and vertical whitespace, respectively.
       
   102 
       
   103 
       
   104 Release 7.1 24-Apr-07
       
   105 ---------------------
       
   106 
       
   107 There is only one new feature in this release: a linebreak setting of
       
   108 PCRE_NEWLINE_ANYCRLF. It is a cut-down version of PCRE_NEWLINE_ANY, which
       
   109 recognizes only CRLF, CR, and LF as linebreaks.
       
   110 
       
   111 A few bugs are fixed (see ChangeLog for details), but the major change is a
       
   112 complete re-implementation of the build system. This now has full Autotools
       
   113 support and so is now "standard" in some sense. It should help with compiling
       
   114 PCRE in a wide variety of environments.
       
   115 
       
   116 NOTE: when building shared libraries for Windows, three dlls are now built,
       
   117 called libpcre, libpcreposix, and libpcrecpp. Previously, everything was
       
   118 included in a single dll.
       
   119 
       
   120 Another important change is that the dftables auxiliary program is no longer
       
   121 compiled and run at "make" time by default. Instead, a default set of character
       
   122 tables (assuming ASCII coding) is used. If you want to use dftables to generate
       
   123 the character tables as previously, add --enable-rebuild-chartables to the
       
   124 "configure" command. You must do this if you are compiling PCRE to run on a
       
   125 system that uses EBCDIC code.
       
   126 
       
   127 There is a discussion about character tables in the README file. The default is
       
   128 not to use dftables so that that there is no problem when cross-compiling.
       
   129 
       
   130 
       
   131 Release 7.0 19-Dec-06
       
   132 ---------------------
       
   133 
       
   134 This release has a new major number because there have been some internal
       
   135 upheavals to facilitate the addition of new optimizations and other facilities,
       
   136 and to make subsequent maintenance and extension easier. Compilation is likely
       
   137 to be a bit slower, but there should be no major effect on runtime performance.
       
   138 Previously compiled patterns are NOT upwards compatible with this release. If
       
   139 you have saved compiled patterns from a previous release, you will have to
       
   140 re-compile them. Important changes that are visible to users are:
       
   141 
       
   142 1. The Unicode property tables have been updated to Unicode 5.0.0, which adds
       
   143    some more scripts.
       
   144 
       
   145 2. The option PCRE_NEWLINE_ANY causes PCRE to recognize any Unicode newline
       
   146    sequence as a newline.
       
   147 
       
   148 3. The \R escape matches a single Unicode newline sequence as a single unit.
       
   149 
       
   150 4. New features that will appear in Perl 5.10 are now in PCRE. These include
       
   151    alternative Perl syntax for named parentheses, and Perl syntax for
       
   152    recursion.
       
   153 
       
   154 5. The C++ wrapper interface has been extended by the addition of a
       
   155    QuoteMeta function and the ability to allow copy construction and
       
   156    assignment.
       
   157 
       
   158 For a complete list of changes, see the ChangeLog file.
       
   159 
       
   160 
       
   161 Release 6.7 04-Jul-06
       
   162 ---------------------
       
   163 
       
   164 The main additions to this release are the ability to use the same name for
       
   165 multiple sets of parentheses, and support for CRLF line endings in both the
       
   166 library and pcregrep (and in pcretest for testing).
       
   167 
       
   168 Thanks to Ian Taylor, the stack usage for many kinds of pattern has been
       
   169 significantly reduced for certain subject strings.
       
   170 
       
   171 
       
   172 Release 6.5 01-Feb-06
       
   173 ---------------------
       
   174 
       
   175 Important changes in this release:
       
   176 
       
   177 1. A number of new features have been added to pcregrep.
       
   178 
       
   179 2. The Unicode property tables have been updated to Unicode 4.1.0, and the
       
   180    supported properties have been extended with script names such as "Arabic",
       
   181    and the derived properties "Any" and "L&". This has necessitated a change to
       
   182    the interal format of compiled patterns. Any saved compiled patterns that
       
   183    use \p or \P must be recompiled.
       
   184 
       
   185 3. The specification of recursion in patterns has been changed so that all
       
   186    recursive subpatterns are automatically treated as atomic groups. Thus, for
       
   187    example, (?R) is treated as if it were (?>(?R)). This is necessary because
       
   188    otherwise there are situations where recursion does not work.
       
   189 
       
   190 See the ChangeLog for a complete list of changes, which include a number of bug
       
   191 fixes and tidies.
       
   192 
       
   193 
       
   194 Release 6.0 07-Jun-05
       
   195 ---------------------
       
   196 
       
   197 The release number has been increased to 6.0 because of the addition of several
       
   198 major new pieces of functionality.
       
   199 
       
   200 A new function, pcre_dfa_exec(), which implements pattern matching using a DFA
       
   201 algorithm, has been added. This has a number of advantages for certain cases,
       
   202 though it does run more slowly, and lacks the ability to capture substrings. On
       
   203 the other hand, it does find all matches, not just the first, and it works
       
   204 better for partial matching. The pcrematching man page discusses the
       
   205 differences.
       
   206 
       
   207 The pcretest program has been enhanced so that it can make use of the new
       
   208 pcre_dfa_exec() matching function and the extra features it provides.
       
   209 
       
   210 The distribution now includes a C++ wrapper library. This is built
       
   211 automatically if a C++ compiler is found. The pcrecpp man page discusses this
       
   212 interface.
       
   213 
       
   214 The code itself has been re-organized into many more files, one for each
       
   215 function, so it no longer requires everything to be linked in when static
       
   216 linkage is used. As a consequence, some internal functions have had to have
       
   217 their names exposed. These functions all have names starting with _pcre_. They
       
   218 are undocumented, and are not intended for use by outside callers.
       
   219 
       
   220 The pcregrep program has been enhanced with new functionality such as
       
   221 multiline-matching and options for output more matching context. See the
       
   222 ChangeLog for a complete list of changes to the library and the utility
       
   223 programs.
       
   224 
       
   225 
       
   226 Release 5.0 13-Sep-04
       
   227 ---------------------
       
   228 
       
   229 The licence under which PCRE is released has been changed to the more
       
   230 conventional "BSD" licence.
       
   231 
       
   232 In the code, some bugs have been fixed, and there are also some major changes
       
   233 in this release (which is why I've increased the number to 5.0). Some changes
       
   234 are internal rearrangements, and some provide a number of new facilities. The
       
   235 new features are:
       
   236 
       
   237 1. There's an "automatic callout" feature that inserts callouts before every
       
   238    item in the regex, and there's a new callout field that gives the position
       
   239    in the pattern - useful for debugging and tracing.
       
   240 
       
   241 2. The extra_data structure can now be used to pass in a set of character
       
   242    tables at exec time. This is useful if compiled regex are saved and re-used
       
   243    at a later time when the tables may not be at the same address. If the
       
   244    default internal tables are used, the pointer saved with the compiled
       
   245    pattern is now set to NULL, which means that you don't need to do anything
       
   246    special unless you are using custom tables.
       
   247 
       
   248 3. It is possible, with some restrictions on the content of the regex, to
       
   249    request "partial" matching. A special return code is given if all of the
       
   250    subject string matched part of the regex. This could be useful for testing
       
   251    an input field as it is being typed.
       
   252 
       
   253 4. There is now some optional support for Unicode character properties, which
       
   254    means that the patterns items such as \p{Lu} and \X can now be used. Only
       
   255    the general category properties are supported. If PCRE is compiled with this
       
   256    support, an additional 90K data structure is include, which increases the
       
   257    size of the library dramatically.
       
   258 
       
   259 5. There is support for saving compiled patterns and re-using them later.
       
   260 
       
   261 6. There is support for running regular expressions that were compiled on a
       
   262    different host with the opposite endianness.
       
   263 
       
   264 7. The pcretest program has been extended to accommodate the new features.
       
   265 
       
   266 The main internal rearrangement is that sequences of literal characters are no
       
   267 longer handled as strings. Instead, each character is handled on its own. This
       
   268 makes some UTF-8 handling easier, and makes the support of partial matching
       
   269 possible. Compiled patterns containing long literal strings will be larger as a
       
   270 result of this change; I hope that performance will not be much affected.
       
   271 
       
   272 
       
   273 Release 4.5 01-Dec-03
       
   274 ---------------------
       
   275 
       
   276 Again mainly a bug-fix and tidying release, with only a couple of new features:
       
   277 
       
   278 1. It's possible now to compile PCRE so that it does not use recursive
       
   279 function calls when matching. Instead it gets memory from the heap. This slows
       
   280 things down, but may be necessary on systems with limited stacks.
       
   281 
       
   282 2. UTF-8 string checking has been tightened to reject overlong sequences and to
       
   283 check that a starting offset points to the start of a character. Failure of the
       
   284 latter returns a new error code: PCRE_ERROR_BADUTF8_OFFSET.
       
   285 
       
   286 3. PCRE can now be compiled for systems that use EBCDIC code.
       
   287 
       
   288 
       
   289 Release 4.4 21-Aug-03
       
   290 ---------------------
       
   291 
       
   292 This is mainly a bug-fix and tidying release. The only new feature is that PCRE
       
   293 checks UTF-8 strings for validity by default. There is an option to suppress
       
   294 this, just in case anybody wants that teeny extra bit of performance.
       
   295 
       
   296 
       
   297 Releases 4.1 - 4.3
       
   298 ------------------
       
   299 
       
   300 Sorry, I forgot about updating the NEWS file for these releases. Please take a
       
   301 look at ChangeLog.
       
   302 
       
   303 
       
   304 Release 4.0 17-Feb-03
       
   305 ---------------------
       
   306 
       
   307 There have been a lot of changes for the 4.0 release, adding additional
       
   308 functionality and mending bugs. Below is a list of the highlights of the new
       
   309 functionality. For full details of these features, please consult the
       
   310 documentation. For a complete list of changes, see the ChangeLog file.
       
   311 
       
   312 1. Support for Perl's \Q...\E escapes.
       
   313 
       
   314 2. "Possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's Java
       
   315 package. They provide some syntactic sugar for simple cases of "atomic
       
   316 grouping".
       
   317 
       
   318 3. Support for the \G assertion. It is true when the current matching position
       
   319 is at the start point of the match.
       
   320 
       
   321 4. A new feature that provides some of the functionality that Perl provides
       
   322 with (?{...}). The facility is termed a "callout". The way it is done in PCRE
       
   323 is for the caller to provide an optional function, by setting pcre_callout to
       
   324 its entry point. To get the function called, the regex must include (?C) at
       
   325 appropriate points.
       
   326 
       
   327 5. Support for recursive calls to individual subpatterns. This makes it really
       
   328 easy to get totally confused.
       
   329 
       
   330 6. Support for named subpatterns. The Python syntax (?P<name>...) is used to
       
   331 name a group.
       
   332 
       
   333 7. Several extensions to UTF-8 support; it is now fairly complete. There is an
       
   334 option for pcregrep to make it operate in UTF-8 mode.
       
   335 
       
   336 8. The single man page has been split into a number of separate man pages.
       
   337 These also give rise to individual HTML pages which are put in a separate
       
   338 directory. There is an index.html page that lists them all. Some hyperlinking
       
   339 between the pages has been installed.
       
   340 
       
   341 
       
   342 Release 3.5 15-Aug-01
       
   343 ---------------------
       
   344 
       
   345 1. The configuring system has been upgraded to use later versions of autoconf
       
   346 and libtool. By default it builds both a shared and a static library if the OS
       
   347 supports it. You can use --disable-shared or --disable-static on the configure
       
   348 command if you want only one of them.
       
   349 
       
   350 2. The pcretest utility is now installed along with pcregrep because it is
       
   351 useful for users (to test regexs) and by doing this, it automatically gets
       
   352 relinked by libtool. The documentation has been turned into a man page, so
       
   353 there are now .1, .txt, and .html versions in /doc.
       
   354 
       
   355 3. Upgrades to pcregrep:
       
   356    (i)   Added long-form option names like gnu grep.
       
   357    (ii)  Added --help to list all options with an explanatory phrase.
       
   358    (iii) Added -r, --recursive to recurse into sub-directories.
       
   359    (iv)  Added -f, --file to read patterns from a file.
       
   360 
       
   361 4. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
       
   362 script, to force use of CR or LF instead of \n in the source. On non-Unix
       
   363 systems, the value can be set in config.h.
       
   364 
       
   365 5. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
       
   366 absolute limit. Changed the text of the error message to make this clear, and
       
   367 likewise updated the man page.
       
   368 
       
   369 6. The limit of 99 on the number of capturing subpatterns has been removed.
       
   370 The new limit is 65535, which I hope will not be a "real" limit.
       
   371 
       
   372 
       
   373 Release 3.3 01-Aug-00
       
   374 ---------------------
       
   375 
       
   376 There is some support for UTF-8 character strings. This is incomplete and
       
   377 experimental. The documentation describes what is and what is not implemented.
       
   378 Otherwise, this is just a bug-fixing release.
       
   379 
       
   380 
       
   381 Release 3.0 01-Feb-00
       
   382 ---------------------
       
   383 
       
   384 1. A "configure" script is now used to configure PCRE for Unix systems. It
       
   385 builds a Makefile, a config.h file, and the pcre-config script.
       
   386 
       
   387 2. PCRE is built as a shared library by default.
       
   388 
       
   389 3. There is support for POSIX classes such as [:alpha:].
       
   390 
       
   391 5. There is an experimental recursion feature.
       
   392 
       
   393 ----------------------------------------------------------------------------
       
   394           IMPORTANT FOR THOSE UPGRADING FROM VERSIONS BEFORE 2.00
       
   395 
       
   396 Please note that there has been a change in the API such that a larger
       
   397 ovector is required at matching time, to provide some additional workspace.
       
   398 The new man page has details. This change was necessary in order to support
       
   399 some of the new functionality in Perl 5.005.
       
   400 
       
   401           IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.00
       
   402 
       
   403 Another (I hope this is the last!) change has been made to the API for the
       
   404 pcre_compile() function. An additional argument has been added to make it
       
   405 possible to pass over a pointer to character tables built in the current
       
   406 locale by pcre_maketables(). To use the default tables, this new arguement
       
   407 should be passed as NULL.
       
   408 
       
   409           IMPORTANT FOR THOSE UPGRADING FROM VERSION 2.05
       
   410 
       
   411 Yet another (and again I hope this really is the last) change has been made
       
   412 to the API for the pcre_exec() function. An additional argument has been
       
   413 added to make it possible to start the match other than at the start of the
       
   414 subject string. This is important if there are lookbehinds. The new man
       
   415 page has the details, but you just want to convert existing programs, all
       
   416 you need to do is to stick in a new fifth argument to pcre_exec(), with a
       
   417 value of zero. For example, change
       
   418 
       
   419   pcre_exec(pattern, extra, subject, length, options, ovec, ovecsize)
       
   420 to
       
   421   pcre_exec(pattern, extra, subject, length, 0, options, ovec, ovecsize)
       
   422 
       
   423 ****