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1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4    Version 7.3 05-Jul-07
5    ---------------------
6    
7     1. In the rejigging of the build system that eventually resulted in 7.1, the
8        line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
9        brackets there is not right, since it causes compilers to look for an
10        installed pcre.h, not the version that is in the source that is being
11        compiled (which of course may be different). I have changed it back to:
12    
13          #include "pcre.h"
14    
15        I have a vague recollection that the change was concerned with compiling in
16        different directories, but in the new build system, that is taken care of
17        by the VPATH setting the Makefile.
18    
19     2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
20        when the subject happened to end in the byte 0x85 (e.g. if the last
21        character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
22        characters but of course it shouldn't be taken as a newline when it is part
23        of another character. The bug was that, for an unlimited repeat of . in
24        not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
25        characters when looking for a newline.
26    
27     3. A small performance improvement in the DOTALL UTF-8 mode .* case.
28    
29     4. Debugging: adjusted the names of opcodes for different kinds of parentheses
30        in debug output.
31    
32     5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
33        long printing in the pcrecpp unittest when running under MinGW.
34    
35     6. ESC_K was left out of the EBCDIC table.
36    
37     7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
38        parentheses; I made it 1000, which seemed large enough. Unfortunately, the
39        limit also applies to "virtual nesting" when a pattern is recursive, and in
40        this case 1000 isn't so big. I have been able to remove this limit at the
41        expense of backing off one optimization in certain circumstances. Normally,
42        when pcre_exec() would call its internal match() function recursively and
43        immediately return the result unconditionally, it uses a "tail recursion"
44        feature to save stack. However, when a subpattern that can match an empty
45        string has an unlimited repetition quantifier, it no longer makes this
46        optimization. That gives it a stack frame in which to save the data for
47        checking that an empty string has been matched. Previously this was taken
48        from the 1000-entry workspace that had been reserved. So now there is no
49        explicit limit, but more stack is used.
50    
51     8. Applied Daniel's patches to solve problems with the import/export magic
52        syntax that is required for Windows, and which was going wrong for the
53        pcreposix and pcrecpp parts of the library. These were overlooked when this
54        problem was solved for the main library.
55    
56     9. There were some crude static tests to avoid integer overflow when computing
57        the size of patterns that contain repeated groups with explicit upper
58        limits. As the maximum quantifier is 65535, the maximum group length was
59        set at 30,000 so that the product of these two numbers did not overflow a
60        32-bit integer. However, it turns out that people want to use groups that
61        are longer than 30,000 bytes (though not repeat them that many times).
62        Change 7.0/17 (the refactoring of the way the pattern size is computed) has
63        made it possible to implement the integer overflow checks in a much more
64        dynamic way, which I have now done. The artificial limitation on group
65        length has been removed - we now have only the limit on the total length of
66        the compiled pattern, which depends on the LINK_SIZE setting.
67    
68    10. Fixed a bug in the documentation for get/copy named substring when
69        duplicate names are permitted. If none of the named substrings are set, the
70        functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
71        empty string.
72    
73    
74    Version 7.2 19-Jun-07
75    ---------------------
76    
77     1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
78        which is apparently normally available under Windows.
79    
80     2. Re-jig the pcregrep tests with different newline settings in an attempt
81        to make them independent of the local environment's newline setting.
82    
83     3. Add code to configure.ac to remove -g from the CFLAGS default settings.
84    
85     4. Some of the "internals" tests were previously cut out when the link size
86        was not 2, because the output contained actual offsets. The recent new
87        "Z" feature of pcretest means that these can be cut out, making the tests
88        usable with all link sizes.
89    
90     5. Implemented Stan Switzer's goto replacement for longjmp() when not using
91        stack recursion. This gives a massive performance boost under BSD, but just
92        a small improvement under Linux. However, it saves one field in the frame
93        in all cases.
94    
95     6. Added more features from the forthcoming Perl 5.10:
96    
97        (a) (?-n) (where n is a string of digits) is a relative subroutine or
98            recursion call. It refers to the nth most recently opened parentheses.
99    
100        (b) (?+n) is also a relative subroutine call; it refers to the nth next
101            to be opened parentheses.
102    
103        (c) Conditions that refer to capturing parentheses can be specified
104            relatively, for example, (?(-2)... or (?(+3)...
105    
106        (d) \K resets the start of the current match so that everything before
107            is not part of it.
108    
109        (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
110    
111        (f) \g{name} is another synonym - part of Perl 5.10's unification of
112            reference syntax.
113    
114        (g) (?| introduces a group in which the numbering of parentheses in each
115            alternative starts with the same number.
116    
117        (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
118    
119     7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
120        PCRE_INFO_JCHANGED.
121    
122     8. A pattern such as  (.*(.)?)*  caused pcre_exec() to fail by either not
123        terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
124        for detecting groups that can match an empty string.
125    
126     9. A pattern with a very large number of alternatives (more than several
127        hundred) was running out of internal workspace during the pre-compile
128        phase, where pcre_compile() figures out how much memory will be needed. A
129        bit of new cunning has reduced the workspace needed for groups with
130        alternatives. The 1000-alternative test pattern now uses 12 bytes of
131        workspace instead of running out of the 4096 that are available.
132    
133    10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
134    
135    11. Applied patch from Google to remove an optimization that didn't quite work.
136        The report of the bug said:
137    
138          pcrecpp::RE("a*").FullMatch("aaa") matches, while
139          pcrecpp::RE("a*?").FullMatch("aaa") does not, and
140          pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
141    
142    12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
143        it matched the wrong number of bytes.
144    
145    
146    Version 7.1 24-Apr-07
147    ---------------------
148    
149     1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
150        that is more "standard", making use of automake and other Autotools. There
151        is some re-arrangement of the files and adjustment of comments consequent
152        on this.
153    
154     2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
155        for recursive directory scanning broke on some systems because the files
156        are not scanned in any specific order and on different systems the order
157        was different. A call to "sort" has been inserted into RunGrepTest for the
158        approprate test as a short-term fix. In the longer term there may be an
159        alternative.
160    
161     3. I had an email from Eric Raymond about problems translating some of PCRE's
162        man pages to HTML (despite the fact that I distribute HTML pages, some
163        people do their own conversions for various reasons). The problems
164        concerned the use of low-level troff macros .br and .in. I have therefore
165        removed all such uses from the man pages (some were redundant, some could
166        be replaced by .nf/.fi pairs). The 132html script that I use to generate
167        HTML has been updated to handle .nf/.fi and to complain if it encounters
168        .br or .in.
169    
170     4. Updated comments in configure.ac that get placed in config.h.in and also
171        arranged for config.h to be included in the distribution, with the name
172        config.h.generic, for the benefit of those who have to compile without
173        Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
174    
175     5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
176        Weber: (1) pcre_internal.h was missing some function renames; (2) updated
177        makevp.bat for the current PCRE, using the additional files
178        makevp_c.txt, makevp_l.txt, and pcregexp.pas.
179    
180     6. A Windows user reported a minor discrepancy with test 2, which turned out
181        to be caused by a trailing space on an input line that had got lost in his
182        copy. The trailing space was an accident, so I've just removed it.
183    
184     7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
185        that is needed.
186    
187     8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
188        as "const" (a) because they are and (b) because it helps the PHP
189        maintainers who have recently made a script to detect big data structures
190        in the php code that should be moved to the .rodata section. I remembered
191        to update Builducptable as well, so it won't revert if ucptable.h is ever
192        re-created.
193    
194     9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
195        pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
196        order to be able to cut out the UTF-8 tables in the latter when UTF-8
197        support is not required. This saves 1.5-2K of code, which is important in
198        some applications.
199    
200        Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
201        so as not to refer to the tables, even though these functions will never be
202        called when UTF-8 support is disabled. Otherwise there are problems with a
203        shared library.
204    
205    10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
206    
207        (a) It was defining its arguments as char * instead of void *.
208    
209        (b) It was assuming that all moves were upwards in memory; this was true
210            a long time ago when I wrote it, but is no longer the case.
211    
212        The emulated memove() is provided for those environments that have neither
213        memmove() nor bcopy(). I didn't think anyone used it these days, but that
214        is clearly not the case, as these two bugs were recently reported.
215    
216    11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
217        and Detrail to create the HTML documentation, the .txt form of the man
218        pages, and it removes trailing spaces from listed files. It also creates
219        pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
220        case, it wraps all the #defines with #ifndefs. This script should be run
221        before "make dist".
222    
223    12. Fixed two fairly obscure bugs concerned with quantified caseless matching
224        with Unicode property support.
225    
226        (a) For a maximizing quantifier, if the two different cases of the
227            character were of different lengths in their UTF-8 codings (there are
228            some cases like this - I found 11), and the matching function had to
229            back up over a mixture of the two cases, it incorrectly assumed they
230            were both the same length.
231    
232        (b) When PCRE was configured to use the heap rather than the stack for
233            recursion during matching, it was not correctly preserving the data for
234            the other case of a UTF-8 character when checking ahead for a match
235            while processing a minimizing repeat. If the check also involved
236            matching a wide character, but failed, corruption could cause an
237            erroneous result when trying to check for a repeat of the original
238            character.
239    
240    13. Some tidying changes to the testing mechanism:
241    
242        (a) The RunTest script now detects the internal link size and whether there
243            is UTF-8 and UCP support by running ./pcretest -C instead of relying on
244            values substituted by "configure". (The RunGrepTest script already did
245            this for UTF-8.) The configure.ac script no longer substitutes the
246            relevant variables.
247    
248        (b) The debugging options /B and /D in pcretest show the compiled bytecode
249            with length and offset values. This means that the output is different
250            for different internal link sizes. Test 2 is skipped for link sizes
251            other than 2 because of this, bypassing the problem. Unfortunately,
252            there was also a test in test 3 (the locale tests) that used /B and
253            failed for link sizes other than 2. Rather than cut the whole test out,
254            I have added a new /Z option to pcretest that replaces the length and
255            offset values with spaces. This is now used to make test 3 independent
256            of link size. (Test 2 will be tidied up later.)
257    
258    14. If erroroffset was passed as NULL to pcre_compile, it provoked a
259        segmentation fault instead of returning the appropriate error message.
260    
261    15. In multiline mode when the newline sequence was set to "any", the pattern
262        ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
263        This doesn't seem right; it now treats the CRLF combination as the line
264        ending, and so does not match in that case. It's only a pattern such as ^$
265        that would hit this one: something like ^ABC$ would have failed after \r
266        and then tried again after \r\n.
267    
268    16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
269        in an attempt to make files that differ only in their line terminators
270        compare equal. This works on Linux.
271    
272    17. Under certain error circumstances pcregrep might try to free random memory
273        as it exited. This is now fixed, thanks to valgrind.
274    
275    19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
276        "abc\r\n\r\n", it found an unwanted second match after the second \r. This
277        was because its rules for how to advance for /g after matching an empty
278        string at the end of a line did not allow for this case. They now check for
279        it specially.
280    
281    20. pcretest is supposed to handle patterns and data of any length, by
282        extending its buffers when necessary. It was getting this wrong when the
283        buffer for a data line had to be extended.
284    
285    21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
286        CRLF as a newline sequence.
287    
288    22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
289        out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
290        I have nevertheless tidied it up.
291    
292    23. Added some casts to kill warnings from HP-UX ia64 compiler.
293    
294    24. Added a man page for pcre-config.
295    
296    
297    Version 7.0 19-Dec-06
298    ---------------------
299    
300     1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
301        moving to gcc 4.1.1.
302    
303     2. The -S option for pcretest uses setrlimit(); I had omitted to #include
304        sys/time.h, which is documented as needed for this function. It doesn't
305        seem to matter on Linux, but it showed up on some releases of OS X.
306    
307     3. It seems that there are systems where bytes whose values are greater than
308        127 match isprint() in the "C" locale. The "C" locale should be the
309        default when a C program starts up. In most systems, only ASCII printing
310        characters match isprint(). This difference caused the output from pcretest
311        to vary, making some of the tests fail. I have changed pcretest so that:
312    
313        (a) When it is outputting text in the compiled version of a pattern, bytes
314            other than 32-126 are always shown as hex escapes.
315    
316        (b) When it is outputting text that is a matched part of a subject string,
317            it does the same, unless a different locale has been set for the match
318            (using the /L modifier). In this case, it uses isprint() to decide.
319    
320     4. Fixed a major bug that caused incorrect computation of the amount of memory
321        required for a compiled pattern when options that changed within the
322        pattern affected the logic of the preliminary scan that determines the
323        length. The relevant options are -x, and -i in UTF-8 mode. The result was
324        that the computed length was too small. The symptoms of this bug were
325        either the PCRE error "internal error: code overflow" from pcre_compile(),
326        or a glibc crash with a message such as "pcretest: free(): invalid next
327        size (fast)". Examples of patterns that provoked this bug (shown in
328        pcretest format) are:
329    
330          /(?-x: )/x
331          /(?x)(?-x: \s*#\s*)/
332          /((?i)[\x{c0}])/8
333          /(?i:[\x{c0}])/8
334    
335        HOWEVER: Change 17 below makes this fix obsolete as the memory computation
336        is now done differently.
337    
338     5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
339        wrapper classes; (b) implement a new function in the C++ scanner that is
340        more efficient than the old way of doing things because it avoids levels of
341        recursion in the regex matching; (c) add a paragraph to the documentation
342        for the FullMatch() function.
343    
344     6. The escape sequence \n was being treated as whatever was defined as
345        "newline". Not only was this contrary to the documentation, which states
346        that \n is character 10 (hex 0A), but it also went horribly wrong when
347        "newline" was defined as CRLF. This has been fixed.
348    
349     7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
350        was being set to -1 for the "end of line" case (supposedly a value that no
351        character can have). Though this value is never used (the check for end of
352        line is "zero bytes in current character"), it caused compiler complaints.
353        I've changed it to 0xffffffff.
354    
355     8. In pcre_version.c, the version string was being built by a sequence of
356        C macros that, in the event of PCRE_PRERELEASE being defined as an empty
357        string (as it is for production releases) called a macro with an empty
358        argument. The C standard says the result of this is undefined. The gcc
359        compiler treats it as an empty string (which was what was wanted) but it is
360        reported that Visual C gives an error. The source has been hacked around to
361        avoid this problem.
362    
363     9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
364        builds of pcretest, and changed the call to _setmode() to use _O_BINARY
365        instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
366        of them did).
367    
368    10. Originally, pcretest opened its input and output without "b"; then I was
369        told that "b" was needed in some environments, so it was added for release
370        5.0 to both the input and output. (It makes no difference on Unix-like
371        systems.) Later I was told that it is wrong for the input on Windows. I've
372        now abstracted the modes into two macros, to make it easier to fiddle with
373        them, and removed "b" from the input mode under Windows.
374    
375    11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
376    
377    12. Added -help and --help to pcretest as an official way of being reminded
378        of the options.
379    
380    13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
381        and pcrecpp.cc because they annoy compilers at high warning levels.
382    
383    14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
384    
385    15. Fixed an occurrence of == in configure.ac that should have been = (shell
386        scripts are not C programs :-) and which was not noticed because it works
387        on Linux.
388    
389    16. pcretest is supposed to handle any length of pattern and data line (as one
390        line or as a continued sequence of lines) by extending its input buffer if
391        necessary. This feature was broken for very long pattern lines, leading to
392        a string of junk being passed to pcre_compile() if the pattern was longer
393        than about 50K.
394    
395    17. I have done a major re-factoring of the way pcre_compile() computes the
396        amount of memory needed for a compiled pattern. Previously, there was code
397        that made a preliminary scan of the pattern in order to do this. That was
398        OK when PCRE was new, but as the facilities have expanded, it has become
399        harder and harder to keep it in step with the real compile phase, and there
400        have been a number of bugs (see for example, 4 above). I have now found a
401        cunning way of running the real compile function in a "fake" mode that
402        enables it to compute how much memory it would need, while actually only
403        ever using a few hundred bytes of working memory and without too many
404        tests of the mode. This should make future maintenance and development
405        easier. A side effect of this work is that the limit of 200 on the nesting
406        depth of parentheses has been removed (though this was never a serious
407        limitation, I suspect). However, there is a downside: pcre_compile() now
408        runs more slowly than before (30% or more, depending on the pattern). I
409        hope this isn't a big issue. There is no effect on runtime performance.
410    
411    18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
412        newline (only possible for the last line of a file) and it was a
413        pattern that set a locale (followed by /Lsomething), pcretest crashed.
414    
415    19. Added additional timing features to pcretest. (1) The -tm option now times
416        matching only, not compiling. (2) Both -t and -tm can be followed, as a
417        separate command line item, by a number that specifies the number of
418        repeats to use when timing. The default is 50000; this gives better
419        precision, but takes uncomfortably long for very large patterns.
420    
421    20. Extended pcre_study() to be more clever in cases where a branch of a
422        subpattern has no definite first character. For example, (a*|b*)[cd] would
423        previously give no result from pcre_study(). Now it recognizes that the
424        first character must be a, b, c, or d.
425    
426    21. There was an incorrect error "recursive call could loop indefinitely" if
427        a subpattern (or the entire pattern) that was being tested for matching an
428        empty string contained only one non-empty item after a nested subpattern.
429        For example, the pattern (?>\x{100}*)\d(?R) provoked this error
430        incorrectly, because the \d was being skipped in the check.
431    
432    22. The pcretest program now has a new pattern option /B and a command line
433        option -b, which is equivalent to adding /B to every pattern. This causes
434        it to show the compiled bytecode, without the additional information that
435        -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
436        is the same as /B/I).
437    
438    23. A new optimization is now able automatically to treat some sequences such
439        as a*b as a*+b. More specifically, if something simple (such as a character
440        or a simple class like \d) has an unlimited quantifier, and is followed by
441        something that cannot possibly match the quantified thing, the quantifier
442        is automatically "possessified".
443    
444    24. A recursive reference to a subpattern whose number was greater than 39
445        went wrong under certain circumstances in UTF-8 mode. This bug could also
446        have affected the operation of pcre_study().
447    
448    25. Realized that a little bit of performance could be had by replacing
449        (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
450    
451    26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
452    
453    27. Possessive quantifiers such as a++ were previously implemented by turning
454        them into atomic groups such as ($>a+). Now they have their own opcodes,
455        which improves performance. This includes the automatically created ones
456        from 23 above.
457    
458    28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
459        lookahead was broken if it was not anchored. PCRE was mistakenly expecting
460        the first matched character to be a colon. This applied both to named and
461        numbered groups.
462    
463    29. The ucpinternal.h header file was missing its idempotency #ifdef.
464    
465    30. I was sent a "project" file called libpcre.a.dev which I understand makes
466        building PCRE on Windows easier, so I have included it in the distribution.
467    
468    31. There is now a check in pcretest against a ridiculously large number being
469        returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
470        loop, the loop is abandoned.
471    
472    32. Forward references to subpatterns in conditions such as (?(2)...) where
473        subpattern 2 is defined later cause pcre_compile() to search forwards in
474        the pattern for the relevant set of parentheses. This search went wrong
475        when there were unescaped parentheses in a character class, parentheses
476        escaped with \Q...\E, or parentheses in a #-comment in /x mode.
477    
478    33. "Subroutine" calls and backreferences were previously restricted to
479        referencing subpatterns earlier in the regex. This restriction has now
480        been removed.
481    
482    34. Added a number of extra features that are going to be in Perl 5.10. On the
483        whole, these are just syntactic alternatives for features that PCRE had
484        previously implemented using the Python syntax or my own invention. The
485        other formats are all retained for compatibility.
486    
487        (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
488            as (?P<name>...). The new forms, as well as being in Perl 5.10, are
489            also .NET compatible.
490    
491        (b) A recursion or subroutine call to a named group can now be defined as
492            (?&name) as well as (?P>name).
493    
494        (c) A backreference to a named group can now be defined as \k<name> or
495            \k'name' as well as (?P=name). The new forms, as well as being in Perl
496            5.10, are also .NET compatible.
497    
498        (d) A conditional reference to a named group can now use the syntax
499            (?(<name>) or (?('name') as well as (?(name).
500    
501        (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
502            groups (named and numbered) that are never evaluated inline, but can be
503            called as "subroutines" from elsewhere. In effect, the DEFINE condition
504            is always false. There may be only one alternative in such a group.
505    
506        (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
507            as the simple (?(R). The condition is true only if the most recent
508            recursion is that of the given number or name. It does not search out
509            through the entire recursion stack.
510    
511        (g) The escape \gN or \g{N} has been added, where N is a positive or
512            negative number, specifying an absolute or relative reference.
513    
514    35. Tidied to get rid of some further signed/unsigned compiler warnings and
515        some "unreachable code" warnings.
516    
517    36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
518        things, this adds five new scripts.
519    
520    37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
521        There were also incompatibilities regarding the handling of \Q..\E inside
522        character classes, for example with patterns like [\Qa\E-\Qz\E] where the
523        hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
524    
525    38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
526        matches an empty string, and forcibly breaks the loop. There were bugs in
527        this code in non-simple cases. For a pattern such as  ^(a()*)*  matched
528        against  aaaa  the result was just "a" rather than "aaaa", for example. Two
529        separate and independent bugs (that affected different cases) have been
530        fixed.
531    
532    39. Refactored the code to abolish the use of different opcodes for small
533        capturing bracket numbers. This is a tidy that I avoided doing when I
534        removed the limit on the number of capturing brackets for 3.5 back in 2001.
535        The new approach is not only tidier, it makes it possible to reduce the
536        memory needed to fix the previous bug (38).
537    
538    40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
539        sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
540        processing dot, circumflex, or dollar metacharacters, or #-comments in /x
541        mode.
542    
543    41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
544        report.
545    
546    42. Applied patch, originally from Ari Pollak, modified by Google, to allow
547        copy construction and assignment in the C++ wrapper.
548    
549    43. Updated pcregrep to support "--newline=any". In the process, I fixed a
550        couple of bugs that could have given wrong results in the "--newline=crlf"
551        case.
552    
553    44. Added a number of casts and did some reorganization of signed/unsigned int
554        variables following suggestions from Dair Grant. Also renamed the variable
555        "this" as "item" because it is a C++ keyword.
556    
557    45. Arranged for dftables to add
558    
559          #include "pcre_internal.h"
560    
561        to pcre_chartables.c because without it, gcc 4.x may remove the array
562        definition from the final binary if PCRE is built into a static library and
563        dead code stripping is activated.
564    
565    46. For an unanchored pattern, if a match attempt fails at the start of a
566        newline sequence, and the newline setting is CRLF or ANY, and the next two
567        characters are CRLF, advance by two characters instead of one.
568    
569    
570    Version 6.7 04-Jul-06
571    ---------------------
572    
573     1. In order to handle tests when input lines are enormously long, pcretest has
574        been re-factored so that it automatically extends its buffers when
575        necessary. The code is crude, but this _is_ just a test program. The
576        default size has been increased from 32K to 50K.
577    
578     2. The code in pcre_study() was using the value of the re argument before
579        testing it for NULL. (Of course, in any sensible call of the function, it
580        won't be NULL.)
581    
582     3. The memmove() emulation function in pcre_internal.h, which is used on
583        systems that lack both memmove() and bcopy() - that is, hardly ever -
584        was missing a "static" storage class specifier.
585    
586     4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
587        containing an extended class (one that cannot be represented by a bitmap
588        because it contains high-valued characters or Unicode property items, e.g.
589        [\pZ]). Almost always one would set UTF-8 mode when processing such a
590        pattern, but PCRE should not loop if you do not (it no longer does).
591        [Detail: two cases were found: (a) a repeated subpattern containing an
592        extended class; (b) a recursive reference to a subpattern that followed a
593        previous extended class. It wasn't skipping over the extended class
594        correctly when UTF-8 mode was not set.]
595    
596     5. A negated single-character class was not being recognized as fixed-length
597        in lookbehind assertions such as (?<=[^f]), leading to an incorrect
598        compile error "lookbehind assertion is not fixed length".
599    
600     6. The RunPerlTest auxiliary script was showing an unexpected difference
601        between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
602        write a Perl script that can interpret lines of an input file either as
603        byte characters or as UTF-8, which is what "perltest" was being required to
604        do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
605        can't do is switch easily at run time between having the "use utf8;" pragma
606        or not. In the end, I fudged it by using the RunPerlTest script to insert
607        "use utf8;" explicitly for the UTF-8 tests.
608    
609     7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
610        the end of the subject string, contrary to the documentation and to what
611        Perl does. This was true of both matching functions. Now it matches only at
612        the start of the subject and immediately after *internal* newlines.
613    
614     8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
615        a pointer to an int instead of a pointer to an unsigned long int. This
616        caused problems on 64-bit systems.
617    
618     9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
619        instance of the 'standard' template library not being so standard".
620    
621    10. There was no check on the number of named subpatterns nor the maximum
622        length of a subpattern name. The product of these values is used to compute
623        the size of the memory block for a compiled pattern. By supplying a very
624        long subpattern name and a large number of named subpatterns, the size
625        computation could be caused to overflow. This is now prevented by limiting
626        the length of names to 32 characters, and the number of named subpatterns
627        to 10,000.
628    
629    11. Subpatterns that are repeated with specific counts have to be replicated in
630        the compiled pattern. The size of memory for this was computed from the
631        length of the subpattern and the repeat count. The latter is limited to
632        65535, but there was no limit on the former, meaning that integer overflow
633        could in principle occur. The compiled length of a repeated subpattern is
634        now limited to 30,000 bytes in order to prevent this.
635    
636    12. Added the optional facility to have named substrings with the same name.
637    
638    13. Added the ability to use a named substring as a condition, using the
639        Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
640        are numbers (not recommended). Forward references are permitted.
641    
642    14. Added forward references in named backreferences (if you see what I mean).
643    
644    15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
645        pattern could run off the end of the subject. For example, the pattern
646        "(?s)(.{1,5})"8 did this with the subject "ab".
647    
648    16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
649        PCRE_CASELESS was set when matching characters that were quantified with ?
650        or *.
651    
652    17. A character class other than a single negated character that had a minimum
653        but no maximum quantifier - for example [ab]{6,} - was not handled
654        correctly by pce_dfa_exec(). It would match only one character.
655    
656    18. A valid (though odd) pattern that looked like a POSIX character
657        class but used an invalid character after [ (for example [[,abc,]]) caused
658        pcre_compile() to give the error "Failed: internal error: code overflow" or
659        in some cases to crash with a glibc free() error. This could even happen if
660        the pattern terminated after [[ but there just happened to be a sequence of
661        letters, a binary zero, and a closing ] in the memory that followed.
662    
663    19. Perl's treatment of octal escapes in the range \400 to \777 has changed
664        over the years. Originally (before any Unicode support), just the bottom 8
665        bits were taken. Thus, for example, \500 really meant \100. Nowadays the
666        output from "man perlunicode" includes this:
667    
668          The regular expression compiler produces polymorphic opcodes.  That
669          is, the pattern adapts to the data and automatically switches to
670          the Unicode character scheme when presented with Unicode data--or
671          instead uses a traditional byte scheme when presented with byte
672          data.
673    
674        Sadly, a wide octal escape does not cause a switch, and in a string with
675        no other multibyte characters, these octal escapes are treated as before.
676        Thus, in Perl, the pattern  /\500/ actually matches \100 but the pattern
677        /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
678        Unicode string.
679    
680        I have not perpetrated such confusion in PCRE. Up till now, it took just
681        the bottom 8 bits, as in old Perl. I have now made octal escapes with
682        values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
683        translate to the appropriate multibyte character.
684    
685    29. Applied some refactoring to reduce the number of warnings from Microsoft
686        and Borland compilers. This has included removing the fudge introduced
687        seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
688        a warning about an unused variable.
689    
690    21. PCRE has not included VT (character 0x0b) in the set of whitespace
691        characters since release 4.0, because Perl (from release 5.004) does not.
692        [Or at least, is documented not to: some releases seem to be in conflict
693        with the documentation.] However, when a pattern was studied with
694        pcre_study() and all its branches started with \s, PCRE still included VT
695        as a possible starting character. Of course, this did no harm; it just
696        caused an unnecessary match attempt.
697    
698    22. Removed a now-redundant internal flag bit that recorded the fact that case
699        dependency changed within the pattern. This was once needed for "required
700        byte" processing, but is no longer used. This recovers a now-scarce options
701        bit. Also moved the least significant internal flag bit to the most-
702        significant bit of the word, which was not previously used (hangover from
703        the days when it was an int rather than a uint) to free up another bit for
704        the future.
705    
706    23. Added support for CRLF line endings as well as CR and LF. As well as the
707        default being selectable at build time, it can now be changed at runtime
708        via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
709        specify that it is scanning data with non-default line endings.
710    
711    24. Changed the definition of CXXLINK to make it agree with the definition of
712        LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
713    
714    25. Applied Ian Taylor's patches to avoid using another stack frame for tail
715        recursions. This makes a big different to stack usage for some patterns.
716    
717    26. If a subpattern containing a named recursion or subroutine reference such
718        as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
719        the space required for the compiled pattern went wrong and gave too small a
720        value. Depending on the environment, this could lead to "Failed: internal
721        error: code overflow at offset 49" or "glibc detected double free or
722        corruption" errors.
723    
724    27. Applied patches from Google (a) to support the new newline modes and (b) to
725        advance over multibyte UTF-8 characters in GlobalReplace.
726    
727    28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
728        difference for some implementation of PCRE in some Windows version.
729    
730    29. Added some extra testing facilities to pcretest:
731    
732        \q<number>   in a data line sets the "match limit" value
733        \Q<number>   in a data line sets the "match recursion limt" value
734        -S <number>  sets the stack size, where <number> is in megabytes
735    
736        The -S option isn't available for Windows.
737    
738    
739    Version 6.6 06-Feb-06
740    ---------------------
741    
742     1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
743        in pcreposix.h. I have copied the definition from pcre.h.
744    
745     2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
746        because pcre.h is no longer a built file.
747    
748     3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
749        not normally included in the compiled code.
750    
751    
752    Version 6.5 01-Feb-06
753    ---------------------
754    
755     1. When using the partial match feature with pcre_dfa_exec(), it was not
756        anchoring the second and subsequent partial matches at the new starting
757        point. This could lead to incorrect results. For example, with the pattern
758        /1234/, partially matching against "123" and then "a4" gave a match.
759    
760     2. Changes to pcregrep:
761    
762        (a) All non-match returns from pcre_exec() were being treated as failures
763            to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
764            error message is output. Some extra information is given for the
765            PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are
766            probably the only errors that are likely to be caused by users (by
767            specifying a regex that has nested indefinite repeats, for instance).
768            If there are more than 20 of these errors, pcregrep is abandoned.
769    
770        (b) A binary zero was treated as data while matching, but terminated the
771            output line if it was written out. This has been fixed: binary zeroes
772            are now no different to any other data bytes.
773    
774        (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
775            used to set a locale for matching. The --locale=xxxx long option has
776            been added (no short equivalent) to specify a locale explicitly on the
777            pcregrep command, overriding the environment variables.
778    
779        (d) When -B was used with -n, some line numbers in the output were one less
780            than they should have been.
781    
782        (e) Added the -o (--only-matching) option.
783    
784        (f) If -A or -C was used with -c (count only), some lines of context were
785            accidentally printed for the final match.
786    
787        (g) Added the -H (--with-filename) option.
788    
789        (h) The combination of options -rh failed to suppress file names for files
790            that were found from directory arguments.
791    
792        (i) Added the -D (--devices) and -d (--directories) options.
793    
794        (j) Added the -F (--fixed-strings) option.
795    
796        (k) Allow "-" to be used as a file name for -f as well as for a data file.
797    
798        (l) Added the --colo(u)r option.
799    
800        (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
801            is not present by default.
802    
803     3. A nasty bug was discovered in the handling of recursive patterns, that is,
804        items such as (?R) or (?1), when the recursion could match a number of
805        alternatives. If it matched one of the alternatives, but subsequently,
806        outside the recursion, there was a failure, the code tried to back up into
807        the recursion. However, because of the way PCRE is implemented, this is not
808        possible, and the result was an incorrect result from the match.
809    
810        In order to prevent this happening, the specification of recursion has
811        been changed so that all such subpatterns are automatically treated as
812        atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
813    
814     4. I had overlooked the fact that, in some locales, there are characters for
815        which isalpha() is true but neither isupper() nor islower() are true. In
816        the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
817        and ordfeminine) are like this. This affected the treatment of \w and \W
818        when they appeared in character classes, but not when they appeared outside
819        a character class. The bit map for "word" characters is now created
820        separately from the results of isalnum() instead of just taking it from the
821        upper, lower, and digit maps. (Plus the underscore character, of course.)
822    
823     5. The above bug also affected the handling of POSIX character classes such as
824        [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
825        permanent tables. Instead, the bit maps for such a class were previously
826        created as the appropriate unions of the upper, lower, and digit bitmaps.
827        Now they are created by subtraction from the [[:word:]] class, which has
828        its own bitmap.
829    
830     6. The [[:blank:]] character class matches horizontal, but not vertical space.
831        It is created by subtracting the vertical space characters (\x09, \x0a,
832        \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
833        subtraction was done in the overall bitmap for a character class, meaning
834        that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
835        be recognized. This bug has been fixed.
836    
837     7. Patches from the folks at Google:
838    
839          (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
840          real life, but is still worth protecting against".
841    
842          (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
843          regular expressions".
844    
845          (c) pcre_scanner.cc: avoid use of std::count() because not all systems
846          have it.
847    
848          (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
849          "configure" and the latter not, in order to fix a problem somebody had
850          with compiling the Arg class on HP-UX.
851    
852          (e) Improve the error-handling of the C++ wrapper a little bit.
853    
854          (f) New tests for checking recursion limiting.
855    
856     8. The pcre_memmove() function, which is used only if the environment does not
857        have a standard memmove() function (and is therefore rarely compiled),
858        contained two bugs: (a) use of int instead of size_t, and (b) it was not
859        returning a result (though PCRE never actually uses the result).
860    
861     9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
862        large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
863        returned instead of calling malloc() with an overflowing number that would
864        most likely cause subsequent chaos.
865    
866    10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
867    
868    11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
869        with this option is matched, the nmatch and pmatch options of regexec() are
870        ignored.
871    
872    12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
873        provided in case anyone wants to the the POSIX interface with UTF-8
874        strings.
875    
876    13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
877        C++ linking (needed for some HP-UX environments).
878    
879    14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
880        (unused parameter) and in the pcre_printint() function (omitted "default"
881        switch label when the default is to do nothing).
882    
883    15. Added some code to make it possible, when PCRE is compiled as a C++
884        library, to replace subject pointers for pcre_exec() with a smart pointer
885        class, thus making it possible to process discontinuous strings.
886    
887    16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
888        much the same function. They were added by different people who were trying
889        to make PCRE easy to compile on non-Unix systems. It has been suggested
890        that PCRE_EXPORT be abolished now that there is more automatic apparatus
891        for compiling on Windows systems. I have therefore replaced it with
892        PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
893        defaults to "extern" for C or "extern C" for C++, which works fine on
894        Unix-like systems. It is now possible to override the value of PCRE_DATA_
895        SCOPE with something explicit in config.h. In addition:
896    
897        (a) pcreposix.h still had just "extern" instead of either of these macros;
898            I have replaced it with PCRE_DATA_SCOPE.
899    
900        (b) Functions such as _pcre_xclass(), which are internal to the library,
901            but external in the C sense, all had PCRE_EXPORT in their definitions.
902            This is apparently wrong for the Windows case, so I have removed it.
903            (It makes no difference on Unix-like systems.)
904    
905    17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
906        of recursive calls to match(). This is different to MATCH_LIMIT because
907        that limits the total number of calls to match(), not all of which increase
908        the depth of recursion. Limiting the recursion depth limits the amount of
909        stack (or heap if NO_RECURSE is set) that is used. The default can be set
910        when PCRE is compiled, and changed at run time. A patch from Google adds
911        this functionality to the C++ interface.
912    
913    18. Changes to the handling of Unicode character properties:
914    
915        (a) Updated the table to Unicode 4.1.0.
916    
917        (b) Recognize characters that are not in the table as "Cn" (undefined).
918    
919        (c) I revised the way the table is implemented to a much improved format
920            which includes recognition of ranges. It now supports the ranges that
921            are defined in UnicodeData.txt, and it also amalgamates other
922            characters into ranges. This has reduced the number of entries in the
923            table from around 16,000 to around 3,000, thus reducing its size
924            considerably. I realized I did not need to use a tree structure after
925            all - a binary chop search is just as efficient. Having reduced the
926            number of entries, I extended their size from 6 bytes to 8 bytes to
927            allow for more data.
928    
929        (d) Added support for Unicode script names via properties such as \p{Han}.
930    
931    19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
932        matching that character.
933    
934    20. When matching a repeated Unicode property with a minimum greater than zero,
935        (for example \pL{2,}), PCRE could look past the end of the subject if it
936        reached it while seeking the minimum number of characters. This could
937        happen only if some of the characters were more than one byte long, because
938        there is a check for at least the minimum number of bytes.
939    
940    21. Refactored the implementation of \p and \P so as to be more general, to
941        allow for more different types of property in future. This has changed the
942        compiled form incompatibly. Anybody with saved compiled patterns that use
943        \p or \P will have to recompile them.
944    
945    22. Added "Any" and "L&" to the supported property types.
946    
947    23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
948        but give a compile time error if the value is greater than 0xff.
949    
950    24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
951        accidentally not being installed or uninstalled.
952    
953    25. The pcre.h file was built from pcre.h.in, but the only changes that were
954        made were to insert the current release number. This seemed silly, because
955        it made things harder for people building PCRE on systems that don't run
956        "configure". I have turned pcre.h into a distributed file, no longer built
957        by "configure", with the version identification directly included. There is
958        no longer a pcre.h.in file.
959    
960        However, this change necessitated a change to the pcre-config script as
961        well. It is built from pcre-config.in, and one of the substitutions was the
962        release number. I have updated configure.ac so that ./configure now finds
963        the release number by grepping pcre.h.
964    
965    26. Added the ability to run the tests under valgrind.
966    
967    
968    Version 6.4 05-Sep-05
969    ---------------------
970    
971     1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
972        "--" to be printed when multiple files were scanned, even when none of the
973        -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
974        consider it to be a bug, and have restored the previous behaviour.
975    
976     2. A couple of code tidies to get rid of compiler warnings.
977    
978     3. The pcretest program used to cheat by referring to symbols in the library
979        whose names begin with _pcre_. These are internal symbols that are not
980        really supposed to be visible externally, and in some environments it is
981        possible to suppress them. The cheating is now confined to including
982        certain files from the library's source, which is a bit cleaner.
983    
984     4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
985        file's purpose clearer.
986    
987     5. Reorganized pcre_ucp_findchar().
988    
989    
990    Version 6.3 15-Aug-05
991    ---------------------
992    
993     1. The file libpcre.pc.in did not have general read permission in the tarball.
994    
995     2. There were some problems when building without C++ support:
996    
997        (a) If C++ support was not built, "make install" and "make test" still
998            tried to test it.
999    
1000        (b) There were problems when the value of CXX was explicitly set. Some
1001            changes have been made to try to fix these, and ...
1002    
1003        (c) --disable-cpp can now be used to explicitly disable C++ support.
1004    
1005        (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
1006            backslash in a target when C++ was disabled. This confuses some
1007            versions of "make", apparently. Using an intermediate variable solves
1008            this. (Same for CPP_LOBJ.)
1009    
1010     3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
1011        (non-Windows) now includes $(CFLAGS) because these flags are sometimes
1012        necessary on certain architectures.
1013    
1014     4. Added a setting of -export-symbols-regex to the link command to remove
1015        those symbols that are exported in the C sense, but actually are local
1016        within the library, and not documented. Their names all begin with
1017        "_pcre_". This is not a perfect job, because (a) we have to except some
1018        symbols that pcretest ("illegally") uses, and (b) the facility isn't always
1019        available (and never for static libraries). I have made a note to try to
1020        find a way round (a) in the future.
1021    
1022    
1023    Version 6.2 01-Aug-05
1024    ---------------------
1025    
1026     1. There was no test for integer overflow of quantifier values. A construction
1027        such as {1111111111111111} would give undefined results. What is worse, if
1028        a minimum quantifier for a parenthesized subpattern overflowed and became
1029        negative, the calculation of the memory size went wrong. This could have
1030        led to memory overwriting.
1031    
1032     2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
1033    
1034     3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
1035        operating environments where this matters.
1036    
1037     4. Applied Giuseppe Maxia's patch to add additional features for controlling
1038        PCRE options from within the C++ wrapper.
1039    
1040     5. Named capturing subpatterns were not being correctly counted when a pattern
1041        was compiled. This caused two problems: (a) If there were more than 100
1042        such subpatterns, the calculation of the memory needed for the whole
1043        compiled pattern went wrong, leading to an overflow error. (b) Numerical
1044        back references of the form \12, where the number was greater than 9, were
1045        not recognized as back references, even though there were sufficient
1046        previous subpatterns.
1047    
1048     6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
1049        versions of gcc, e.g. 2.95.4.
1050    
1051    
1052    Version 6.1 21-Jun-05
1053    ---------------------
1054    
1055     1. There was one reference to the variable "posix" in pcretest.c that was not
1056        surrounded by "#if !defined NOPOSIX".
1057    
1058     2. Make it possible to compile pcretest without DFA support, UTF8 support, or
1059        the cross-check on the old pcre_info() function, for the benefit of the
1060        cut-down version of PCRE that is currently imported into Exim.
1061    
1062     3. A (silly) pattern starting with (?i)(?-i) caused an internal space
1063        allocation error. I've done the easy fix, which wastes 2 bytes for sensible
1064        patterns that start (?i) but I don't think that matters. The use of (?i) is
1065        just an example; this all applies to the other options as well.
1066    
1067     4. Since libtool seems to echo the compile commands it is issuing, the output
1068        from "make" can be reduced a bit by putting "@" in front of each libtool
1069        compile command.
1070    
1071     5. Patch from the folks at Google for configure.in to be a bit more thorough
1072        in checking for a suitable C++ installation before trying to compile the
1073        C++ stuff. This should fix a reported problem when a compiler was present,
1074        but no suitable headers.
1075    
1076     6. The man pages all had just "PCRE" as their title. I have changed them to
1077        be the relevant file name. I have also arranged that these names are
1078        retained in the file doc/pcre.txt, which is a concatenation in text format
1079        of all the man pages except the little individual ones for each function.
1080    
1081     7. The NON-UNIX-USE file had not been updated for the different set of source
1082        files that come with release 6. I also added a few comments about the C++
1083        wrapper.
1084    
1085    
1086    Version 6.0 07-Jun-05
1087    ---------------------
1088    
1089     1. Some minor internal re-organization to help with my DFA experiments.
1090    
1091     2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
1092        didn't matter for the library itself when fully configured, but did matter
1093        when compiling without UCP support, or within Exim, where the ucp files are
1094        not imported.
1095    
1096     3. Refactoring of the library code to split up the various functions into
1097        different source modules. The addition of the new DFA matching code (see
1098        below) to a single monolithic source would have made it really too
1099        unwieldy, quite apart from causing all the code to be include in a
1100        statically linked application, when only some functions are used. This is
1101        relevant even without the DFA addition now that patterns can be compiled in
1102        one application and matched in another.
1103    
1104        The downside of splitting up is that there have to be some external
1105        functions and data tables that are used internally in different modules of
1106        the library but which are not part of the API. These have all had their
1107        names changed to start with "_pcre_" so that they are unlikely to clash
1108        with other external names.
1109    
1110     4. Added an alternate matching function, pcre_dfa_exec(), which matches using
1111        a different (DFA) algorithm. Although it is slower than the original
1112        function, it does have some advantages for certain types of matching
1113        problem.
1114    
1115     5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
1116        including restarting after a partial match.
1117    
1118     6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
1119        defined when compiling for Windows was sent to me. I have put it into the
1120        code, though I have no means of testing or verifying it.
1121    
1122     7. Added the pcre_refcount() auxiliary function.
1123    
1124     8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
1125        match before or at the first newline in the subject string. In pcretest,
1126        the /f option on a pattern can be used to set this.
1127    
1128     9. A repeated \w when used in UTF-8 mode with characters greater than 256
1129        would behave wrongly. This has been present in PCRE since release 4.0.
1130    
1131    10. A number of changes to the pcregrep command:
1132    
1133        (a) Refactored how -x works; insert ^(...)$ instead of setting
1134            PCRE_ANCHORED and checking the length, in preparation for adding
1135            something similar for -w.
1136    
1137        (b) Added the -w (match as a word) option.
1138    
1139        (c) Refactored the way lines are read and buffered so as to have more
1140            than one at a time available.
1141    
1142        (d) Implemented a pcregrep test script.
1143    
1144        (e) Added the -M (multiline match) option. This allows patterns to match
1145            over several lines of the subject. The buffering ensures that at least
1146            8K, or the rest of the document (whichever is the shorter) is available
1147            for matching (and similarly the previous 8K for lookbehind assertions).
1148    
1149        (f) Changed the --help output so that it now says
1150    
1151              -w, --word-regex(p)
1152    
1153            instead of two lines, one with "regex" and the other with "regexp"
1154            because that confused at least one person since the short forms are the
1155            same. (This required a bit of code, as the output is generated
1156            automatically from a table. It wasn't just a text change.)
1157    
1158        (g) -- can be used to terminate pcregrep options if the next thing isn't an
1159            option but starts with a hyphen. Could be a pattern or a path name
1160            starting with a hyphen, for instance.
1161    
1162        (h) "-" can be given as a file name to represent stdin.
1163    
1164        (i) When file names are being printed, "(standard input)" is used for
1165            the standard input, for compatibility with GNU grep. Previously
1166            "<stdin>" was used.
1167    
1168        (j) The option --label=xxx can be used to supply a name to be used for
1169            stdin when file names are being printed. There is no short form.
1170    
1171        (k) Re-factored the options decoding logic because we are going to add
1172            two more options that take data. Such options can now be given in four
1173            different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
1174    
1175        (l) Added the -A, -B, and -C options for requesting that lines of context
1176            around matches be printed.
1177    
1178        (m) Added the -L option to print the names of files that do not contain
1179            any matching lines, that is, the complement of -l.
1180    
1181        (n) The return code is 2 if any file cannot be opened, but pcregrep does
1182            continue to scan other files.
1183    
1184        (o) The -s option was incorrectly implemented. For compatibility with other
1185            greps, it now suppresses the error message for a non-existent or non-
1186            accessible file (but not the return code). There is a new option called
1187            -q that suppresses the output of matching lines, which was what -s was
1188            previously doing.
1189    
1190        (p) Added --include and --exclude options to specify files for inclusion
1191            and exclusion when recursing.
1192    
1193    11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
1194        Hopefully, it now does.
1195    
1196    12. Missing cast in pcre_study().
1197    
1198    13. Added an "uninstall" target to the makefile.
1199    
1200    14. Replaced "extern" in the function prototypes in Makefile.in with
1201        "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
1202        world, but is set differently for Windows.
1203    
1204    15. Added a second compiling function called pcre_compile2(). The only
1205        difference is that it has an extra argument, which is a pointer to an
1206        integer error code. When there is a compile-time failure, this is set
1207        non-zero, in addition to the error test pointer being set to point to an
1208        error message. The new argument may be NULL if no error number is required
1209        (but then you may as well call pcre_compile(), which is now just a
1210        wrapper). This facility is provided because some applications need a
1211        numeric error indication, but it has also enabled me to tidy up the way
1212        compile-time errors are handled in the POSIX wrapper.
1213    
1214    16. Added VPATH=.libs to the makefile; this should help when building with one
1215        prefix path and installing with another. (Or so I'm told by someone who
1216        knows more about this stuff than I do.)
1217    
1218    17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
1219        passes PCRE_DOTALL to the pcre_compile() function, making the "." character
1220        match everything, including newlines. This is not POSIX-compatible, but
1221        somebody wanted the feature. From pcretest it can be activated by using
1222        both the P and the s flags.
1223    
1224    18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
1225    
1226    19. libpcre.pc was being incorrectly installed as executable.
1227    
1228    20. A couple of places in pcretest check for end-of-line by looking for '\n';
1229        it now also looks for '\r' so that it will work unmodified on Windows.
1230    
1231    21. Added Google's contributed C++ wrapper to the distribution.
1232    
1233    22. Added some untidy missing memory free() calls in pcretest, to keep
1234        Electric Fence happy when testing.
1235    
1236    
1237    
1238    Version 5.0 13-Sep-04
1239    ---------------------
1240    
1241     1. Internal change: literal characters are no longer packed up into items
1242        containing multiple characters in a single byte-string. Each character
1243        is now matched using a separate opcode. However, there may be more than one
1244        byte in the character in UTF-8 mode.
1245    
1246     2. The pcre_callout_block structure has two new fields: pattern_position and
1247        next_item_length. These contain the offset in the pattern to the next match
1248        item, and its length, respectively.
1249    
1250     3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
1251        insertion of callouts before each pattern item. Added the /C option to
1252        pcretest to make use of this.
1253    
1254     4. On the advice of a Windows user, the lines
1255    
1256          #if defined(_WIN32) || defined(WIN32)
1257          _setmode( _fileno( stdout ), 0x8000 );
1258          #endif  /* defined(_WIN32) || defined(WIN32) */
1259    
1260        have been added to the source of pcretest. This apparently does useful
1261        magic in relation to line terminators.
1262    
1263     5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
1264        for the benefit of those environments where the "b" makes a difference.
1265    
1266     6. The icc compiler has the same options as gcc, but "configure" doesn't seem
1267        to know about it. I have put a hack into configure.in that adds in code
1268        to set GCC=yes if CC=icc. This seems to end up at a point in the
1269        generated configure script that is early enough to affect the setting of
1270        compiler options, which is what is needed, but I have no means of testing
1271        whether it really works. (The user who reported this had patched the
1272        generated configure script, which of course I cannot do.)
1273    
1274        LATER: After change 22 below (new libtool files), the configure script
1275        seems to know about icc (and also ecc). Therefore, I have commented out
1276        this hack in configure.in.
1277    
1278     7. Added support for pkg-config (2 patches were sent in).
1279    
1280     8. Negated POSIX character classes that used a combination of internal tables
1281        were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
1282        [[:^ascii]]. Typically, they would match almost any characters. The other
1283        POSIX classes were not broken in this way.
1284    
1285     9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
1286        to find the match, as PCRE was deluded into thinking that the match had to
1287        start at the start point or following a newline. The same bug applied to
1288        patterns with negative forward assertions or any backward assertions
1289        preceding ".*" at the start, unless the pattern required a fixed first
1290        character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
1291    
1292    10. In UTF-8 mode, when moving forwards in the subject after a failed match
1293        starting at the last subject character, bytes beyond the end of the subject
1294        string were read.
1295    
1296    11. Renamed the variable "class" as "classbits" to make life easier for C++
1297        users. (Previously there was a macro definition, but it apparently wasn't
1298        enough.)
1299    
1300    12. Added the new field "tables" to the extra data so that tables can be passed
1301        in at exec time, or the internal tables can be re-selected. This allows
1302        a compiled regex to be saved and re-used at a later time by a different
1303        program that might have everything at different addresses.
1304    
1305    13. Modified the pcre-config script so that, when run on Solaris, it shows a
1306        -R library as well as a -L library.
1307    
1308    14. The debugging options of pcretest (-d on the command line or D on a
1309        pattern) showed incorrect output for anything following an extended class
1310        that contained multibyte characters and which was followed by a quantifier.
1311    
1312    15. Added optional support for general category Unicode character properties
1313        via the \p, \P, and \X escapes. Unicode property support implies UTF-8
1314        support. It adds about 90K to the size of the library. The meanings of the
1315        inbuilt class escapes such as \d and \s have NOT been changed.
1316    
1317    16. Updated pcredemo.c to include calls to free() to release the memory for the
1318        compiled pattern.
1319    
1320    17. The generated file chartables.c was being created in the source directory
1321        instead of in the building directory. This caused the build to fail if the
1322        source directory was different from the building directory, and was
1323        read-only.
1324    
1325    18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
1326        file. No doubt somebody will tell me if they don't make sense... Also added
1327        Dan Mooney's comments about building on OpenVMS.
1328    
1329    19. Added support for partial matching via the PCRE_PARTIAL option for
1330        pcre_exec() and the \P data escape in pcretest.
1331    
1332    20. Extended pcretest with 3 new pattern features:
1333    
1334        (i)   A pattern option of the form ">rest-of-line" causes pcretest to
1335              write the compiled pattern to the file whose name is "rest-of-line".
1336              This is a straight binary dump of the data, with the saved pointer to
1337              the character tables forced to be NULL. The study data, if any, is
1338              written too. After writing, pcretest reads a new pattern.
1339    
1340        (ii)  If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
1341              compiled pattern from the given file. There must not be any
1342              occurrences of "<" in the file name (pretty unlikely); if there are,
1343              pcretest will instead treat the initial "<" as a pattern delimiter.
1344              After reading in the pattern, pcretest goes on to read data lines as
1345              usual.
1346    
1347        (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
1348              and 16-bit fields in a compiled pattern, to simulate a pattern that
1349              was compiled on a host of opposite endianness.
1350    
1351    21. The pcre-exec() function can now cope with patterns that were compiled on
1352        hosts of opposite endianness, with this restriction:
1353    
1354          As for any compiled expression that is saved and used later, the tables
1355          pointer field cannot be preserved; the extra_data field in the arguments
1356          to pcre_exec() should be used to pass in a tables address if a value
1357          other than the default internal tables were used at compile time.
1358    
1359    22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
1360        now diagnosed as an error. Previously, most of the time, a negative number
1361        would have been treated as zero, but if in addition "ovector" was passed as
1362        NULL, a crash could occur.
1363    
1364    23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
1365        new versions from the libtool 1.5 distribution (the last one is a copy of
1366        a file called libtool.m4). This seems to have fixed the need to patch
1367        "configure" to support Darwin 1.3 (which I used to do). However, I still
1368        had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
1369        workstation).
1370    
1371    24. Changed the PCRE licence to be the more standard "BSD" licence.
1372    
1373    
1374    Version 4.5 01-Dec-03
1375    ---------------------
1376    
1377     1. There has been some re-arrangement of the code for the match() function so
1378        that it can be compiled in a version that does not call itself recursively.
1379        Instead, it keeps those local variables that need separate instances for
1380        each "recursion" in a frame on the heap, and gets/frees frames whenever it
1381        needs to "recurse". Keeping track of where control must go is done by means
1382        of setjmp/longjmp. The whole thing is implemented by a set of macros that
1383        hide most of the details from the main code, and operates only if
1384        NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
1385        "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
1386        operating.
1387    
1388        To make it easier for callers to provide specially tailored get/free
1389        functions for this usage, two new functions, pcre_stack_malloc, and
1390        pcre_stack_free, are used. They are always called in strict stacking order,
1391        and the size of block requested is always the same.
1392    
1393        The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
1394        PCRE has been compiled to use the stack or the heap for recursion. The
1395        -C option of pcretest uses this to show which version is compiled.
1396    
1397        A new data escape \S, is added to pcretest; it causes the amounts of store
1398        obtained and freed by both kinds of malloc/free at match time to be added
1399        to the output.
1400    
1401     2. Changed the locale test to use "fr_FR" instead of "fr" because that's
1402        what's available on my current Linux desktop machine.
1403    
1404     3. When matching a UTF-8 string, the test for a valid string at the start has
1405        been extended. If start_offset is not zero, PCRE now checks that it points
1406        to a byte that is the start of a UTF-8 character. If not, it returns
1407        PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
1408        this is necessary because there may be backward assertions in the pattern.
1409        When matching the same subject several times, it may save resources to use
1410        PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
1411    
1412     4. The code for checking the validity of UTF-8 strings has been tightened so
1413        that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
1414        containing "overlong sequences".
1415    
1416     5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
1417        I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
1418        should have been "&", but it just so happened that all the cases this let
1419        through by mistake were picked up later in the function.
1420    
1421     6. I had used a variable called "isblank" - this is a C99 function, causing
1422        some compilers to warn. To avoid this, I renamed it (as "blankclass").
1423    
1424     7. Cosmetic: (a) only output another newline at the end of pcretest if it is
1425        prompting; (b) run "./pcretest /dev/null" at the start of the test script
1426        so the version is shown; (c) stop "make test" echoing "./RunTest".
1427    
1428     8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
1429    
1430     9. The prototype for memmove() for systems that don't have it was using
1431        size_t, but the inclusion of the header that defines size_t was later. I've
1432        moved the #includes for the C headers earlier to avoid this.
1433    
1434    10. Added some adjustments to the code to make it easier to compiler on certain
1435        special systems:
1436    
1437          (a) Some "const" qualifiers were missing.
1438          (b) Added the macro EXPORT before all exported functions; by default this
1439              is defined to be empty.
1440          (c) Changed the dftables auxiliary program (that builds chartables.c) so
1441              that it reads its output file name as an argument instead of writing
1442              to the standard output and assuming this can be redirected.
1443    
1444    11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
1445        class containing characters with values greater than 255, PCRE compilation
1446        went into a loop.
1447    
1448    12. A recursive reference to a subpattern that was within another subpattern
1449        that had a minimum quantifier of zero caused PCRE to crash. For example,
1450        (x(y(?2))z)? provoked this bug with a subject that got as far as the
1451        recursion. If the recursively-called subpattern itself had a zero repeat,
1452        that was OK.
1453    
1454    13. In pcretest, the buffer for reading a data line was set at 30K, but the
1455        buffer into which it was copied (for escape processing) was still set at
1456        1024, so long lines caused crashes.
1457    
1458    14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
1459        "internal error: code overflow...". This applied to any character class
1460        that was followed by a possessive quantifier.
1461    
1462    15. Modified the Makefile to add libpcre.la as a prerequisite for
1463        libpcreposix.la because I was told this is needed for a parallel build to
1464        work.
1465    
1466    16. If a pattern that contained .* following optional items at the start was
1467        studied, the wrong optimizing data was generated, leading to matching
1468        errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
1469        matching string must start with a or b or c. The correct conclusion for
1470        this pattern is that a match can start with any character.
1471    
1472    
1473    Version 4.4 13-Aug-03
1474    ---------------------
1475    
1476     1. In UTF-8 mode, a character class containing characters with values between
1477        127 and 255 was not handled correctly if the compiled pattern was studied.
1478        In fixing this, I have also improved the studying algorithm for such
1479        classes (slightly).
1480    
1481     2. Three internal functions had redundant arguments passed to them. Removal
1482        might give a very teeny performance improvement.
1483    
1484     3. Documentation bug: the value of the capture_top field in a callout is *one
1485        more than* the number of the hightest numbered captured substring.
1486    
1487     4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
1488        in incorrectly linking with a previously installed version. They now link
1489        explicitly with libpcre.la.
1490    
1491     5. configure.in no longer needs to recognize Cygwin specially.
1492    
1493     6. A problem in pcre.in for Windows platforms is fixed.
1494    
1495     7. If a pattern was successfully studied, and the -d (or /D) flag was given to
1496        pcretest, it used to include the size of the study block as part of its
1497        output. Unfortunately, the structure contains a field that has a different
1498        size on different hardware architectures. This meant that the tests that
1499        showed this size failed. As the block is currently always of a fixed size,
1500        this information isn't actually particularly useful in pcretest output, so
1501        I have just removed it.
1502    
1503     8. Three pre-processor statements accidentally did not start in column 1.
1504        Sadly, there are *still* compilers around that complain, even though
1505        standard C has not required this for well over a decade. Sigh.
1506    
1507     9. In pcretest, the code for checking callouts passed small integers in the
1508        callout_data field, which is a void * field. However, some picky compilers
1509        complained about the casts involved for this on 64-bit systems. Now
1510        pcretest passes the address of the small integer instead, which should get
1511        rid of the warnings.
1512    
1513    10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
1514        both compile and run time, and gives an error if an invalid UTF-8 sequence
1515        is found. There is a option for disabling this check in cases where the
1516        string is known to be correct and/or the maximum performance is wanted.
1517    
1518    11. In response to a bug report, I changed one line in Makefile.in from
1519    
1520            -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
1521        to
1522            -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
1523    
1524        to look similar to other lines, but I have no way of telling whether this
1525        is the right thing to do, as I do not use Windows. No doubt I'll get told
1526        if it's wrong...
1527    
1528    
1529    Version 4.3 21-May-03
1530    ---------------------
1531    
1532    1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
1533       Makefile.
1534    
1535    2. Some refactoring to improve the quality of the code:
1536    
1537       (i)   The utf8_table... variables are now declared "const".
1538    
1539       (ii)  The code for \cx, which used the "case flipping" table to upper case
1540             lower case letters, now just substracts 32. This is ASCII-specific,
1541             but the whole concept of \cx is ASCII-specific, so it seems
1542             reasonable.
1543    
1544       (iii) PCRE was using its character types table to recognize decimal and
1545             hexadecimal digits in the pattern. This is silly, because it handles
1546             only 0-9, a-f, and A-F, but the character types table is locale-
1547             specific, which means strange things might happen. A private
1548             table is now used for this - though it costs 256 bytes, a table is
1549             much faster than multiple explicit tests. Of course, the standard
1550             character types table is still used for matching digits in subject
1551             strings against \d.
1552    
1553       (iv)  Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
1554             ending in _t are). So I've renamed it as ESC_tee.
1555    
1556    3. The first argument for regexec() in the POSIX wrapper should have been
1557       defined as "const".
1558    
1559    4. Changed pcretest to use malloc() for its buffers so that they can be
1560       Electric Fenced for debugging.
1561    
1562    5. There were several places in the code where, in UTF-8 mode, PCRE would try
1563       to read one or more bytes before the start of the subject string. Often this
1564       had no effect on PCRE's behaviour, but in some circumstances it could
1565       provoke a segmentation fault.
1566    
1567    6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
1568       to try to read one or more bytes before the start of the subject string.
1569    
1570    7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
1571       UTF-8 support could misbehave in various ways if the subject string
1572       contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
1573       area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
1574       back over UTF-8 characters.)
1575    
1576    
1577    Version 4.2 14-Apr-03
1578    ---------------------
1579    
1580    1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
1581    
1582    2. Changes to the building process, supplied by Ronald Landheer-Cieslak
1583         [ON_WINDOWS]: new variable, "#" on non-Windows platforms
1584         [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
1585         [WIN_PREFIX]: new variable, "cyg" for Cygwin
1586         * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
1587           and BUILD_EXEEXT
1588         Note: automatic setting of the BUILD variables is not yet working
1589         set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
1590           compile-time but not at link-time
1591         [LINK]: use for linking executables only
1592         make different versions for Windows and non-Windows
1593         [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
1594           libraries
1595         [LINK_FOR_BUILD]: new variable
1596         [OBJEXT]: use throughout
1597         [EXEEXT]: use throughout
1598         <winshared>: new target
1599         <wininstall>: new target
1600         <dftables.o>: use native compiler
1601         <dftables>: use native linker
1602         <install>: handle Windows platform correctly
1603         <clean>: ditto
1604         <check>: ditto
1605         copy DLL to top builddir before testing
1606    
1607       As part of these changes, -no-undefined was removed again. This was reported
1608       to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
1609       in any case.
1610    
1611    3. Some tidies to get rid of compiler warnings:
1612    
1613       . In the match_data structure, match_limit was an unsigned long int, whereas
1614         match_call_count was an int. I've made them both unsigned long ints.
1615    
1616       . In pcretest the fact that a const uschar * doesn't automatically cast to
1617         a void * provoked a warning.
1618    
1619       . Turning on some more compiler warnings threw up some "shadow" variables
1620         and a few more missing casts.
1621    
1622    4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
1623       option, a class that contained a single character with a value between 128
1624       and 255 (e.g. /[\xFF]/) caused PCRE to crash.
1625    
1626    5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
1627       option, a class that contained several characters, but with at least one
1628       whose value was between 128 and 255 caused PCRE to crash.
1629    
1630    
1631    Version 4.1 12-Mar-03
1632    ---------------------
1633    
1634    1. Compiling with gcc -pedantic found a couple of places where casts were
1635    needed, and a string in dftables.c that was longer than standard compilers are
1636    required to support.
1637    
1638    2. Compiling with Sun's compiler found a few more places where the code could
1639    be tidied up in order to avoid warnings.
1640    
1641    3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
1642    first of these names is deprecated in the latest Autoconf in favour of the name
1643    CC_FOR_BUILD, because "host" is typically used to mean the system on which the
1644    compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
1645    analogy I have changed it to CFLAGS_FOR_BUILD.
1646    
1647    4. Added -no-undefined to the linking command in the Makefile, because this is
1648    apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
1649    linking step for the pcreposix library.
1650    
1651    5. PCRE was failing to diagnose the case of two named groups with the same
1652    name.
1653    
1654    6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
1655    literal character that is needed in the subject for a match, and scans along to
1656    ensure that it is present before embarking on the full matching process. This
1657    saves time in cases of nested unlimited repeats that are never going to match.
1658    Problem: the scan can take a lot of time if the subject is very long (e.g.
1659    megabytes), thus penalizing straightforward matches. It is now done only if the
1660    amount of subject to be scanned is less than 1000 bytes.
1661    
1662    7. A lesser problem with the same optimization is that it was recording the
1663    first character of an anchored pattern as "needed", thus provoking a search
1664    right along the subject, even when the first match of the pattern was going to
1665    fail. The "needed" character is now not set for anchored patterns, unless it
1666    follows something in the pattern that is of non-fixed length. Thus, it still
1667    fulfils its original purpose of finding quick non-matches in cases of nested
1668    unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
1669    
1670    
1671    Version 4.0 17-Feb-03
1672    ---------------------
1673    
1674    1. If a comment in an extended regex that started immediately after a meta-item
1675    extended to the end of string, PCRE compiled incorrect data. This could lead to
1676    all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
1677    
1678    2. Moved to autoconf 2.53 and libtool 1.4.2.
1679    
1680    3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
1681    the special perltest8 script is no longer needed - all the tests can be run
1682    from a single perltest script.
1683    
1684    4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
1685    by \s. It has now been removed in PCRE. This means it isn't recognized as
1686    whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
1687    class [:space:] *does* include VT, thereby creating a mess.
1688    
1689    5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
1690    space and tab.
1691    
1692    6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
1693    its new features into the main test script, reducing the number of scripts.
1694    
1695    7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
1696    were backward compatible, and made the (?i) apply to the whole pattern, as if
1697    /i were given. Now it behaves more logically, and applies the option setting
1698    only to what follows. PCRE has been changed to follow suit. However, if it
1699    finds options settings right at the start of the pattern, it extracts them into
1700    the global options, as before. Thus, they show up in the info data.
1701    
1702    8. Added support for the \Q...\E escape sequence. Characters in between are
1703    treated as literals. This is slightly different from Perl in that $ and @ are
1704    also handled as literals inside the quotes. In Perl, they will cause variable
1705    interpolation. Note the following examples:
1706    
1707        Pattern            PCRE matches      Perl matches
1708    
1709        \Qabc$xyz\E        abc$xyz           abc followed by the contents of $xyz
1710        \Qabc\$xyz\E       abc\$xyz          abc\$xyz
1711        \Qabc\E\$\Qxyz\E   abc$xyz           abc$xyz
1712    
1713    For compatibility with Perl, \Q...\E sequences are recognized inside character
1714    classes as well as outside them.
1715    
1716    9. Re-organized 3 code statements in pcretest to avoid "overflow in
1717    floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
1718    (size_t) cast to one statement in pcretest and one in pcreposix to avoid
1719    signed/unsigned warnings.
1720    
1721    10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
1722    option for pcretest, so I've replaced it by a simple function that does just
1723    that job.
1724    
1725    11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
1726    "pcregrep -".
1727    
1728    12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
1729    Java package. This provides some syntactic sugar for simple cases of what my
1730    documentation calls "once-only subpatterns". A pattern such as x*+ is the same
1731    as (?>x*). In other words, if what is inside (?>...) is just a single repeated
1732    item, you can use this simplified notation. Note that only makes sense with
1733    greedy quantifiers. Consequently, the use of the possessive quantifier forces
1734    greediness, whatever the setting of the PCRE_UNGREEDY option.
1735    
1736    13. A change of greediness default within a pattern was not taking effect at
1737    the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
1738    subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
1739    was abstracted outside.
1740    
1741    14. PCRE now supports the \G assertion. It is true when the current matching
1742    position is at the start point of the match. This differs from \A when the
1743    starting offset is non-zero. Used with the /g option of pcretest (or similar
1744    code), it works in the same way as it does for Perl's /g option. If all
1745    alternatives of a regex begin with \G, the expression is anchored to the start
1746    match position, and the "anchored" flag is set in the compiled expression.
1747    
1748    15. Some bugs concerning the handling of certain option changes within patterns
1749    have been fixed. These applied to options other than (?ims). For example,
1750    "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
1751    been the other way round. Some of this was related to change 7 above.
1752    
1753    16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
1754    features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
1755    and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
1756    POSIX classes only within a class (e.g. /[[:alpha:]]/).
1757    
1758    17. Added support for Perl's \C escape. This matches one byte, even in UTF8
1759    mode. Unlike ".", it always matches newline, whatever the setting of
1760    PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
1761    assertions. Perl allows it, but it doesn't (in general) work because it can't
1762    calculate the length of the lookbehind. At least, that's the case for Perl
1763    5.8.0 - I've been told they are going to document that it doesn't work in
1764    future.
1765    
1766    18. Added an error diagnosis for escapes that PCRE does not support: these are
1767    \L, \l, \N, \P, \p, \U, \u, and \X.
1768    
1769    19. Although correctly diagnosing a missing ']' in a character class, PCRE was
1770    reading past the end of the pattern in cases such as /[abcd/.
1771    
1772    20. PCRE was getting more memory than necessary for patterns with classes that
1773    contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
1774    
1775    21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
1776    compiling PCRE for use with Virtual Pascal.
1777    
1778    22. Small fix to the Makefile to make it work properly if the build is done
1779    outside the source tree.
1780    
1781    23. Added a new extension: a condition to go with recursion. If a conditional
1782    subpattern starts with (?(R) the "true" branch is used if recursion has
1783    happened, whereas the "false" branch is used only at the top level.
1784    
1785    24. When there was a very long string of literal characters (over 255 bytes
1786    without UTF support, over 250 bytes with UTF support), the computation of how
1787    much memory was required could be incorrect, leading to segfaults or other
1788    strange effects.
1789    
1790    25. PCRE was incorrectly assuming anchoring (either to start of subject or to
1791    start of line for a non-DOTALL pattern) when a pattern started with (.*) and
1792    there was a subsequent back reference to those brackets. This meant that, for
1793    example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
1794    possible to check for precisely this case. All we can do is abandon the
1795    optimization if .* occurs inside capturing brackets when there are any back
1796    references whatsoever. (See below for a better fix that came later.)
1797    
1798    26. The handling of the optimization for finding the first character of a
1799    non-anchored pattern, and for finding a character that is required later in the
1800    match were failing in some cases. This didn't break the matching; it just
1801    failed to optimize when it could. The way this is done has been re-implemented.
1802    
1803    27. Fixed typo in error message for invalid (?R item (it said "(?p").
1804    
1805    28. Added a new feature that provides some of the functionality that Perl
1806    provides with (?{...}). The facility is termed a "callout". The way it is done
1807    in PCRE is for the caller to provide an optional function, by setting
1808    pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
1809    global variable. By default it is unset, which disables all calling out. To get
1810    the function called, the regex must include (?C) at appropriate points. This
1811    is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
1812    This provides a means of identifying different callout points. When PCRE
1813    reaches such a point in the regex, if pcre_callout has been set, the external
1814    function is called. It is provided with data in a structure called
1815    pcre_callout_block, which is defined in pcre.h. If the function returns 0,
1816    matching continues; if it returns a non-zero value, the match at the current
1817    point fails. However, backtracking will occur if possible. [This was changed
1818    later and other features added - see item 49 below.]
1819    
1820    29. pcretest is upgraded to test the callout functionality. It provides a
1821    callout function that displays information. By default, it shows the start of
1822    the match and the current position in the text. There are some new data escapes
1823    to vary what happens:
1824    
1825        \C+         in addition, show current contents of captured substrings
1826        \C-         do not supply a callout function
1827        \C!n        return 1 when callout number n is reached
1828        \C!n!m      return 1 when callout number n is reached for the mth time
1829    
1830    30. If pcregrep was called with the -l option and just a single file name, it
1831    output "<stdin>" if a match was found, instead of the file name.
1832    
1833    31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
1834    slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
1835    pcre_exec(). This saves a malloc/free per call. The default value of
1836    POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
1837    when configuring.
1838    
1839    32. The default maximum size of a compiled pattern is 64K. There have been a
1840    few cases of people hitting this limit. The code now uses macros to handle the
1841    storing of links as offsets within the compiled pattern. It defaults to 2-byte
1842    links, but this can be changed to 3 or 4 bytes by --with-link-size when
1843    configuring. Tests 2 and 5 work only with 2-byte links because they output
1844    debugging information about compiled patterns.
1845    
1846    33. Internal code re-arrangements:
1847    
1848    (a) Moved the debugging function for printing out a compiled regex into
1849        its own source file (printint.c) and used #include to pull it into
1850        pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
1851        separate copies.
1852    
1853    (b) Defined the list of op-code names for debugging as a macro in
1854        internal.h so that it is next to the definition of the opcodes.
1855    
1856    (c) Defined a table of op-code lengths for simpler skipping along compiled
1857        code. This is again a macro in internal.h so that it is next to the
1858        definition of the opcodes.
1859    
1860    34. Added support for recursive calls to individual subpatterns, along the
1861    lines of Robin Houston's patch (but implemented somewhat differently).
1862    
1863    35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
1864    allow it to read and process whole directories in Win32. This code was
1865    contributed by Lionel Fourquaux; it has not been tested by me.
1866    
1867    36. Added support for named subpatterns. The Python syntax (?P<name>...) is
1868    used to name a group. Names consist of alphanumerics and underscores, and must
1869    be unique. Back references use the syntax (?P=name) and recursive calls use
1870    (?P>name) which is a PCRE extension to the Python extension. Groups still have
1871    numbers. The function pcre_fullinfo() can be used after compilation to extract
1872    a name/number map. There are three relevant calls:
1873    
1874      PCRE_INFO_NAMEENTRYSIZE        yields the size of each entry in the map
1875      PCRE_INFO_NAMECOUNT            yields the number of entries
1876      PCRE_INFO_NAMETABLE            yields a pointer to the map.
1877    
1878    The map is a vector of fixed-size entries. The size of each entry depends on
1879    the length of the longest name used. The first two bytes of each entry are the
1880    group number, most significant byte first. There follows the corresponding
1881    name, zero terminated. The names are in alphabetical order.
1882    
1883    37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
1884    case instead of 255. Making it the same both with and without UTF-8 support
1885    means that the same test output works with both.
1886    
1887    38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
1888    calling malloc() with a zero argument.
1889    
1890    39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
1891    optimization. I've improved things by keeping a bitmap of backreferences with
1892    numbers 1-31 so that if .* occurs inside capturing brackets that are not in
1893    fact referenced, the optimization can be applied. It is unlikely that a
1894    relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
1895    the match to follow \n) will appear inside brackets with a number greater than
1896    31, but if it does, any back reference > 31 suppresses the optimization.
1897    
1898    40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
1899    of disabling numbered capturing parentheses. Any opening parenthesis that is
1900    not followed by ? behaves as if it were followed by ?: but named parentheses
1901    can still be used for capturing (and they will acquire numbers in the usual
1902    way).
1903    
1904    41. Redesigned the return codes from the match() function into yes/no/error so
1905    that errors can be passed back from deep inside the nested calls. A malloc
1906    failure while inside a recursive subpattern call now causes the
1907    PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
1908    
1909    42. It is now possible to set a limit on the number of times the match()
1910    function is called in a call to pcre_exec(). This facility makes it possible to
1911    limit the amount of recursion and backtracking, though not in a directly
1912    obvious way, because the match() function is used in a number of different
1913    circumstances. The count starts from zero for each position in the subject
1914    string (for non-anchored patterns). The default limit is, for compatibility, a
1915    large number, namely 10 000 000. You can change this in two ways:
1916    
1917    (a) When configuring PCRE before making, you can use --with-match-limit=n
1918        to set a default value for the compiled library.
1919    
1920    (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
1921        a different value is set. See 45 below.
1922    
1923    If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
1924    
1925    43. Added a new function pcre_config(int, void *) to enable run-time extraction
1926    of things that can be changed at compile time. The first argument specifies
1927    what is wanted and the second points to where the information is to be placed.
1928    The current list of available information is:
1929    
1930      PCRE_CONFIG_UTF8
1931    
1932    The output is an integer that is set to one if UTF-8 support is available;
1933    otherwise it is set to zero.
1934    
1935      PCRE_CONFIG_NEWLINE
1936    
1937    The output is an integer that it set to the value of the code that is used for
1938    newline. It is either LF (10) or CR (13).
1939    
1940      PCRE_CONFIG_LINK_SIZE
1941    
1942    The output is an integer that contains the number of bytes used for internal
1943    linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
1944    
1945      PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
1946    
1947    The output is an integer that contains the threshold above which the POSIX
1948    interface uses malloc() for output vectors. See item 31 above.
1949    
1950      PCRE_CONFIG_MATCH_LIMIT
1951    
1952    The output is an unsigned integer that contains the default limit of the number
1953    of match() calls in a pcre_exec() execution. See 42 above.
1954    
1955    44. pcretest has been upgraded by the addition of the -C option. This causes it
1956    to extract all the available output from the new pcre_config() function, and to
1957    output it. The program then exits immediately.
1958    
1959    45. A need has arisen to pass over additional data with calls to pcre_exec() in
1960    order to support additional features. One way would have been to define
1961    pcre_exec2() (for example) with extra arguments, but this would not have been
1962    extensible, and would also have required all calls to the original function to
1963    be mapped to the new one. Instead, I have chosen to extend the mechanism that
1964    is used for passing in "extra" data from pcre_study().
1965    
1966    The pcre_extra structure is now exposed and defined in pcre.h. It currently
1967    contains the following fields:
1968    
1969      flags         a bitmap indicating which of the following fields are set
1970      study_data    opaque data from pcre_study()
1971      match_limit   a way of specifying a limit on match() calls for a specific
1972                      call to pcre_exec()
1973      callout_data  data for callouts (see 49 below)
1974    
1975    The flag bits are also defined in pcre.h, and are
1976    
1977      PCRE_EXTRA_STUDY_DATA
1978      PCRE_EXTRA_MATCH_LIMIT
1979      PCRE_EXTRA_CALLOUT_DATA
1980    
1981    The pcre_study() function now returns one of these new pcre_extra blocks, with
1982    the actual study data pointed to by the study_data field, and the
1983    PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
1984    before. That is, this change is entirely upwards-compatible and requires no
1985    change to existing code.
1986    
1987    If you want to pass in additional data to pcre_exec(), you can either place it
1988    in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
1989    block.
1990    
1991    46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
1992    data string contains the escape sequence \M, pcretest calls pcre_exec() several
1993    times with different match limits, until it finds the minimum value needed for
1994    pcre_exec() to complete. The value is then output. This can be instructive; for
1995    most simple matches the number is quite small, but for pathological cases it
1996    gets very large very quickly.
1997    
1998    47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
1999    returns the size of the data block pointed to by the study_data field in a
2000    pcre_extra block, that is, the value that was passed as the argument to
2001    pcre_malloc() when PCRE was getting memory in which to place the information
2002    created by pcre_study(). The fourth argument should point to a size_t variable.
2003    pcretest has been extended so that this information is shown after a successful
2004    pcre_study() call when information about the compiled regex is being displayed.
2005    
2006    48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
2007    because what follows is always an absolute path. (Later: it turns out that this
2008    is more than cosmetic for MinGW, because it doesn't like empty path
2009    components.)
2010    
2011    49. Some changes have been made to the callout feature (see 28 above):
2012    
2013    (i)  A callout function now has three choices for what it returns:
2014    
2015           0  =>  success, carry on matching
2016         > 0  =>  failure at this point, but backtrack if possible
2017         < 0  =>  serious error, return this value from pcre_exec()
2018    
2019         Negative values should normally be chosen from the set of PCRE_ERROR_xxx
2020         values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
2021         "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
2022         use by callout functions. It will never be used by PCRE itself.
2023    
2024    (ii) The pcre_extra structure (see 45 above) has a void * field called
2025         callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
2026         pcre_callout_block structure has a field of the same name. The contents of
2027         the field passed in the pcre_extra structure are passed to the callout
2028         function in the corresponding field in the callout block. This makes it
2029         easier to use the same callout-containing regex from multiple threads. For
2030         testing, the pcretest program has a new data escape
2031    
2032           \C*n        pass the number n (may be negative) as callout_data
2033    
2034         If the callout function in pcretest receives a non-zero value as
2035         callout_data, it returns that value.
2036    
2037    50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
2038    there were some redundant $(CFLAGS) in commands that are now specified as
2039    $(LINK), which already includes $(CFLAGS).
2040    
2041    51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
2042    has been compiled with UTF-8 support *and* pcre_compile() has been compiled
2043    with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
2044    one-byte characters throughout. Note that case-insensitive matching applies
2045    only to characters whose values are less than 256. PCRE doesn't support the
2046    notion of cases for higher-valued characters.
2047    
2048    (i)   A character class whose characters are all within 0-255 is handled as
2049          a bit map, and the map is inverted for negative classes. Previously, a
2050          character > 255 always failed to match such a class; however it should
2051          match if the class was a negative one (e.g. [^ab]). This has been fixed.
2052    
2053    (ii)  A negated character class with a single character < 255 is coded as
2054          "not this character" (OP_NOT). This wasn't working properly when the test
2055          character was multibyte, either singly or repeated.
2056    
2057    (iii) Repeats of multibyte characters are now handled correctly in UTF-8
2058          mode, for example: \x{100}{2,3}.
2059    
2060    (iv)  The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
2061          singly or repeated) now correctly test multibyte characters. However,
2062          PCRE doesn't recognize any characters with values greater than 255 as
2063          digits, spaces, or word characters. Such characters always match \D, \S,
2064          and \W, and never match \d, \s, or \w.
2065    
2066    (v)   Classes may now contain characters and character ranges with values
2067          greater than 255. For example: [ab\x{100}-\x{400}].
2068    
2069    (vi)  pcregrep now has a --utf-8 option (synonym -u) which makes it call
2070          PCRE in UTF-8 mode.
2071    
2072    52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
2073    PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
2074    retained for backwards compatibility. (Note that LASTLITERAL is also a byte
2075    value.)
2076    
2077    53. The single man page has become too large. I have therefore split it up into
2078    a number of separate man pages. These also give rise to individual HTML pages;
2079    these are now put in a separate directory, and there is an index.html page that
2080    lists them all. Some hyperlinking between the pages has been installed.
2081    
2082    54. Added convenience functions for handling named capturing parentheses.
2083    
2084    55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
2085    aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
2086    true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
2087    are faulted.
2088    
2089    56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
2090    calling configure. These values are used when compiling the dftables.c program
2091    which is run to generate the source of the default character tables. They
2092    default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
2093    you will need to set these values.
2094    
2095    57. Updated the building process for Windows DLL, as provided by Fred Cox.
2096    
2097    
2098    Version 3.9 02-Jan-02
2099    ---------------------
2100    
2101    1. A bit of extraneous text had somehow crept into the pcregrep documentation.
2102    
2103    2. If --disable-static was given, the building process failed when trying to
2104    build pcretest and pcregrep. (For some reason it was using libtool to compile
2105    them, which is not right, as they aren't part of the library.)
2106    
2107    
2108    Version 3.8 18-Dec-01
2109    ---------------------
2110    
2111    1. The experimental UTF-8 code was completely screwed up. It was packing the
2112    bytes in the wrong order. How dumb can you get?
2113    
2114    
2115    Version 3.7 29-Oct-01
2116    ---------------------
2117    
2118    1. In updating pcretest to check change 1 of version 3.6, I screwed up.
2119    This caused pcretest, when used on the test data, to segfault. Unfortunately,
2120    this didn't happen under Solaris 8, where I normally test things.
2121    
2122    2. The Makefile had to be changed to make it work on BSD systems, where 'make'
2123    doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
2124    isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
2125    this fix an hour or so after the initial 3.7 release.)
2126    
2127    
2128    Version 3.6 23-Oct-01
2129    ---------------------
2130    
2131    1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
2132    offsets passed as NULL with zero offset count.
2133    
2134    2. The config.guess and config.sub files had not been updated when I moved to
2135    the latest autoconf.
2136    
2137    
2138    Version 3.5 15-Aug-01
2139    ---------------------
2140    
2141    1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
2142    had been forgotten.
2143    
2144    2. By using declared but undefined structures, we can avoid using "void"
2145    definitions in pcre.h while keeping the internal definitions of the structures
2146    private.
2147    
2148    3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
2149    user point of view, this means that both static and shared libraries are built
2150    by default, but this can be individually controlled. More of the work of
2151    handling this static/shared cases is now inside libtool instead of PCRE's make
2152    file.
2153    
2154    4. The pcretest utility is now installed along with pcregrep because it is
2155    useful for users (to test regexs) and by doing this, it automatically gets
2156    relinked by libtool. The documentation has been turned into a man page, so
2157    there are now .1, .txt, and .html versions in /doc.
2158    
2159    5. Upgrades to pcregrep:
2160       (i)   Added long-form option names like gnu grep.
2161       (ii)  Added --help to list all options with an explanatory phrase.
2162       (iii) Added -r, --recursive to recurse into sub-directories.
2163       (iv)  Added -f, --file to read patterns from a file.
2164    
2165    6. pcre_exec() was referring to its "code" argument before testing that
2166    argument for NULL (and giving an error if it was NULL).
2167    
2168    7. Upgraded Makefile.in to allow for compiling in a different directory from
2169    the source directory.
2170    
2171    8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
2172    options bits, the pointer it was passed was to an int instead of to an unsigned
2173    long int. This mattered only on 64-bit systems.
2174    
2175    9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
2176    generated) instead of pcre.in, which it its source. Also made the same change
2177    in several of the .c files.
2178    
2179    10. A new release of gcc defines printf() as a macro, which broke pcretest
2180    because it had an ifdef in the middle of a string argument for printf(). Fixed
2181    by using separate calls to printf().
2182    
2183    11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
2184    script, to force use of CR or LF instead of \n in the source. On non-Unix
2185    systems, the value can be set in config.h.
2186    
2187    12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
2188    absolute limit. Changed the text of the error message to make this clear, and
2189    likewise updated the man page.
2190    
2191    13. The limit of 99 on the number of capturing subpatterns has been removed.
2192    The new limit is 65535, which I hope will not be a "real" limit.
2193    
2194    
2195    Version 3.4 22-Aug-00
2196    ---------------------
2197    
2198    1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
2199    
2200    2. Diagnose condition (?(0) as an error instead of crashing on matching.
2201    
2202    
2203    Version 3.3 01-Aug-00
2204    ---------------------
2205    
2206    1. If an octal character was given, but the value was greater than \377, it
2207    was not getting masked to the least significant bits, as documented. This could
2208    lead to crashes in some systems.
2209    
2210    2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
2211    the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
2212    
2213    3. Added the functions pcre_free_substring() and pcre_free_substring_list().
2214    These just pass their arguments on to (pcre_free)(), but they are provided
2215    because some uses of PCRE bind it to non-C systems that can call its functions,
2216    but cannot call free() or pcre_free() directly.
2217    
2218    4. Add "make test" as a synonym for "make check". Corrected some comments in
2219    the Makefile.
2220    
2221    5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
2222    Makefile.
2223    
2224    6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
2225    command called pgrep for grepping around the active processes.
2226    
2227    7. Added the beginnings of support for UTF-8 character strings.
2228    
2229    8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
2230    RANLIB to ./ltconfig so that they are used by libtool. I think these are all
2231    the relevant ones. (AR is not passed because ./ltconfig does its own figuring
2232    out for the ar command.)
2233    
2234    
2235  Version 3.2 12-May-00  Version 3.2 12-May-00
2236  ---------------------  ---------------------

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