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1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
3    
4    Version 6.2 01-Aug-05
5    ---------------------
6    
7     1. There was no test for integer overflow of quantifier values. A construction
8        such as {1111111111111111} would give undefined results. What is worse, if
9        a minimum quantifier for a parenthesized subpattern overflowed and became
10        negative, the calculation of the memory size went wrong. This could have
11        led to memory overwriting.
12    
13     2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
14    
15     3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
16        operating environments where this matters.
17    
18     4. Applied Giuseppe Maxia's patch to add additional features for controlling
19        PCRE options from within the C++ wrapper.
20    
21     5. Named capturing subpatterns were not being correctly counted when a pattern
22        was compiled. This caused two problems: (a) If there were more than 100
23        such subpatterns, the calculation of the memory needed for the whole
24        compiled pattern went wrong, leading to an overflow error. (b) Numerical
25        back references of the form \12, where the number was greater than 9, were
26        not recognized as back references, even though there were sufficient
27        previous subpatterns.
28    
29     6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
30        versions of gcc, e.g. 2.95.4.
31    
32    
33    Version 6.1 21-Jun-05
34    ---------------------
35    
36     1. There was one reference to the variable "posix" in pcretest.c that was not
37        surrounded by "#if !defined NOPOSIX".
38    
39     2. Make it possible to compile pcretest without DFA support, UTF8 support, or
40        the cross-check on the old pcre_info() function, for the benefit of the
41        cut-down version of PCRE that is currently imported into Exim.
42    
43     3. A (silly) pattern starting with (?i)(?-i) caused an internal space
44        allocation error. I've done the easy fix, which wastes 2 bytes for sensible
45        patterns that start (?i) but I don't think that matters. The use of (?i) is
46        just an example; this all applies to the other options as well.
47    
48     4. Since libtool seems to echo the compile commands it is issuing, the output
49        from "make" can be reduced a bit by putting "@" in front of each libtool
50        compile command.
51    
52     5. Patch from the folks at Google for configure.in to be a bit more thorough
53        in checking for a suitable C++ installation before trying to compile the
54        C++ stuff. This should fix a reported problem when a compiler was present,
55        but no suitable headers.
56    
57     6. The man pages all had just "PCRE" as their title. I have changed them to
58        be the relevant file name. I have also arranged that these names are
59        retained in the file doc/pcre.txt, which is a concatenation in text format
60        of all the man pages except the little individual ones for each function.
61    
62     7. The NON-UNIX-USE file had not been updated for the different set of source
63        files that come with release 6. I also added a few comments about the C++
64        wrapper.
65    
66    
67    Version 6.0 07-Jun-05
68    ---------------------
69    
70     1. Some minor internal re-organization to help with my DFA experiments.
71    
72     2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
73        didn't matter for the library itself when fully configured, but did matter
74        when compiling without UCP support, or within Exim, where the ucp files are
75        not imported.
76    
77     3. Refactoring of the library code to split up the various functions into
78        different source modules. The addition of the new DFA matching code (see
79        below) to a single monolithic source would have made it really too
80        unwieldy, quite apart from causing all the code to be include in a
81        statically linked application, when only some functions are used. This is
82        relevant even without the DFA addition now that patterns can be compiled in
83        one application and matched in another.
84    
85        The downside of splitting up is that there have to be some external
86        functions and data tables that are used internally in different modules of
87        the library but which are not part of the API. These have all had their
88        names changed to start with "_pcre_" so that they are unlikely to clash
89        with other external names.
90    
91     4. Added an alternate matching function, pcre_dfa_exec(), which matches using
92        a different (DFA) algorithm. Although it is slower than the original
93        function, it does have some advantages for certain types of matching
94        problem.
95    
96     5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
97        including restarting after a partial match.
98    
99     6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
100        defined when compiling for Windows was sent to me. I have put it into the
101        code, though I have no means of testing or verifying it.
102    
103     7. Added the pcre_refcount() auxiliary function.
104    
105     8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
106        match before or at the first newline in the subject string. In pcretest,
107        the /f option on a pattern can be used to set this.
108    
109     9. A repeated \w when used in UTF-8 mode with characters greater than 256
110        would behave wrongly. This has been present in PCRE since release 4.0.
111    
112    10. A number of changes to the pcregrep command:
113    
114        (a) Refactored how -x works; insert ^(...)$ instead of setting
115            PCRE_ANCHORED and checking the length, in preparation for adding
116            something similar for -w.
117    
118        (b) Added the -w (match as a word) option.
119    
120        (c) Refactored the way lines are read and buffered so as to have more
121            than one at a time available.
122    
123        (d) Implemented a pcregrep test script.
124    
125        (e) Added the -M (multiline match) option. This allows patterns to match
126            over several lines of the subject. The buffering ensures that at least
127            8K, or the rest of the document (whichever is the shorter) is available
128            for matching (and similarly the previous 8K for lookbehind assertions).
129    
130        (f) Changed the --help output so that it now says
131    
132              -w, --word-regex(p)
133    
134            instead of two lines, one with "regex" and the other with "regexp"
135            because that confused at least one person since the short forms are the
136            same. (This required a bit of code, as the output is generated
137            automatically from a table. It wasn't just a text change.)
138    
139        (g) -- can be used to terminate pcregrep options if the next thing isn't an
140            option but starts with a hyphen. Could be a pattern or a path name
141            starting with a hyphen, for instance.
142    
143        (h) "-" can be given as a file name to represent stdin.
144    
145        (i) When file names are being printed, "(standard input)" is used for
146            the standard input, for compatibility with GNU grep. Previously
147            "<stdin>" was used.
148    
149        (j) The option --label=xxx can be used to supply a name to be used for
150            stdin when file names are being printed. There is no short form.
151    
152        (k) Re-factored the options decoding logic because we are going to add
153            two more options that take data. Such options can now be given in four
154            different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
155    
156        (l) Added the -A, -B, and -C options for requesting that lines of context
157            around matches be printed.
158    
159        (m) Added the -L option to print the names of files that do not contain
160            any matching lines, that is, the complement of -l.
161    
162        (n) The return code is 2 if any file cannot be opened, but pcregrep does
163            continue to scan other files.
164    
165        (o) The -s option was incorrectly implemented. For compatibility with other
166            greps, it now suppresses the error message for a non-existent or non-
167            accessible file (but not the return code). There is a new option called
168            -q that suppresses the output of matching lines, which was what -s was
169            previously doing.
170    
171        (p) Added --include and --exclude options to specify files for inclusion
172            and exclusion when recursing.
173    
174    11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
175        Hopefully, it now does.
176    
177    12. Missing cast in pcre_study().
178    
179    13. Added an "uninstall" target to the makefile.
180    
181    14. Replaced "extern" in the function prototypes in Makefile.in with
182        "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
183        world, but is set differently for Windows.
184    
185    15. Added a second compiling function called pcre_compile2(). The only
186        difference is that it has an extra argument, which is a pointer to an
187        integer error code. When there is a compile-time failure, this is set
188        non-zero, in addition to the error test pointer being set to point to an
189        error message. The new argument may be NULL if no error number is required
190        (but then you may as well call pcre_compile(), which is now just a
191        wrapper). This facility is provided because some applications need a
192        numeric error indication, but it has also enabled me to tidy up the way
193        compile-time errors are handled in the POSIX wrapper.
194    
195    16. Added VPATH=.libs to the makefile; this should help when building with one
196        prefix path and installing with another. (Or so I'm told by someone who
197        knows more about this stuff than I do.)
198    
199    17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
200        passes PCRE_DOTALL to the pcre_compile() function, making the "." character
201        match everything, including newlines. This is not POSIX-compatible, but
202        somebody wanted the feature. From pcretest it can be activated by using
203        both the P and the s flags.
204    
205    18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
206    
207    19. libpcre.pc was being incorrectly installed as executable.
208    
209    20. A couple of places in pcretest check for end-of-line by looking for '\n';
210        it now also looks for '\r' so that it will work unmodified on Windows.
211    
212    21. Added Google's contributed C++ wrapper to the distribution.
213    
214    22. Added some untidy missing memory free() calls in pcretest, to keep
215        Electric Fence happy when testing.
216    
217    
218    
219    Version 5.0 13-Sep-04
220    ---------------------
221    
222     1. Internal change: literal characters are no longer packed up into items
223        containing multiple characters in a single byte-string. Each character
224        is now matched using a separate opcode. However, there may be more than one
225        byte in the character in UTF-8 mode.
226    
227     2. The pcre_callout_block structure has two new fields: pattern_position and
228        next_item_length. These contain the offset in the pattern to the next match
229        item, and its length, respectively.
230    
231     3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
232        insertion of callouts before each pattern item. Added the /C option to
233        pcretest to make use of this.
234    
235     4. On the advice of a Windows user, the lines
236    
237          #if defined(_WIN32) || defined(WIN32)
238          _setmode( _fileno( stdout ), 0x8000 );
239          #endif  /* defined(_WIN32) || defined(WIN32) */
240    
241        have been added to the source of pcretest. This apparently does useful
242        magic in relation to line terminators.
243    
244     5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
245        for the benefit of those environments where the "b" makes a difference.
246    
247     6. The icc compiler has the same options as gcc, but "configure" doesn't seem
248        to know about it. I have put a hack into configure.in that adds in code
249        to set GCC=yes if CC=icc. This seems to end up at a point in the
250        generated configure script that is early enough to affect the setting of
251        compiler options, which is what is needed, but I have no means of testing
252        whether it really works. (The user who reported this had patched the
253        generated configure script, which of course I cannot do.)
254    
255        LATER: After change 22 below (new libtool files), the configure script
256        seems to know about icc (and also ecc). Therefore, I have commented out
257        this hack in configure.in.
258    
259     7. Added support for pkg-config (2 patches were sent in).
260    
261     8. Negated POSIX character classes that used a combination of internal tables
262        were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
263        [[:^ascii]]. Typically, they would match almost any characters. The other
264        POSIX classes were not broken in this way.
265    
266     9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
267        to find the match, as PCRE was deluded into thinking that the match had to
268        start at the start point or following a newline. The same bug applied to
269        patterns with negative forward assertions or any backward assertions
270        preceding ".*" at the start, unless the pattern required a fixed first
271        character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
272    
273    10. In UTF-8 mode, when moving forwards in the subject after a failed match
274        starting at the last subject character, bytes beyond the end of the subject
275        string were read.
276    
277    11. Renamed the variable "class" as "classbits" to make life easier for C++
278        users. (Previously there was a macro definition, but it apparently wasn't
279        enough.)
280    
281    12. Added the new field "tables" to the extra data so that tables can be passed
282        in at exec time, or the internal tables can be re-selected. This allows
283        a compiled regex to be saved and re-used at a later time by a different
284        program that might have everything at different addresses.
285    
286    13. Modified the pcre-config script so that, when run on Solaris, it shows a
287        -R library as well as a -L library.
288    
289    14. The debugging options of pcretest (-d on the command line or D on a
290        pattern) showed incorrect output for anything following an extended class
291        that contained multibyte characters and which was followed by a quantifier.
292    
293    15. Added optional support for general category Unicode character properties
294        via the \p, \P, and \X escapes. Unicode property support implies UTF-8
295        support. It adds about 90K to the size of the library. The meanings of the
296        inbuilt class escapes such as \d and \s have NOT been changed.
297    
298    16. Updated pcredemo.c to include calls to free() to release the memory for the
299        compiled pattern.
300    
301    17. The generated file chartables.c was being created in the source directory
302        instead of in the building directory. This caused the build to fail if the
303        source directory was different from the building directory, and was
304        read-only.
305    
306    18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
307        file. No doubt somebody will tell me if they don't make sense... Also added
308        Dan Mooney's comments about building on OpenVMS.
309    
310    19. Added support for partial matching via the PCRE_PARTIAL option for
311        pcre_exec() and the \P data escape in pcretest.
312    
313    20. Extended pcretest with 3 new pattern features:
314    
315        (i)   A pattern option of the form ">rest-of-line" causes pcretest to
316              write the compiled pattern to the file whose name is "rest-of-line".
317              This is a straight binary dump of the data, with the saved pointer to
318              the character tables forced to be NULL. The study data, if any, is
319              written too. After writing, pcretest reads a new pattern.
320    
321        (ii)  If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
322              compiled pattern from the given file. There must not be any
323              occurrences of "<" in the file name (pretty unlikely); if there are,
324              pcretest will instead treat the initial "<" as a pattern delimiter.
325              After reading in the pattern, pcretest goes on to read data lines as
326              usual.
327    
328        (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
329              and 16-bit fields in a compiled pattern, to simulate a pattern that
330              was compiled on a host of opposite endianness.
331    
332    21. The pcre-exec() function can now cope with patterns that were compiled on
333        hosts of opposite endianness, with this restriction:
334    
335          As for any compiled expression that is saved and used later, the tables
336          pointer field cannot be preserved; the extra_data field in the arguments
337          to pcre_exec() should be used to pass in a tables address if a value
338          other than the default internal tables were used at compile time.
339    
340    22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
341        now diagnosed as an error. Previously, most of the time, a negative number
342        would have been treated as zero, but if in addition "ovector" was passed as
343        NULL, a crash could occur.
344    
345    23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
346        new versions from the libtool 1.5 distribution (the last one is a copy of
347        a file called libtool.m4). This seems to have fixed the need to patch
348        "configure" to support Darwin 1.3 (which I used to do). However, I still
349        had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
350        workstation).
351    
352    24. Changed the PCRE licence to be the more standard "BSD" licence.
353    
354    
355    Version 4.5 01-Dec-03
356    ---------------------
357    
358     1. There has been some re-arrangement of the code for the match() function so
359        that it can be compiled in a version that does not call itself recursively.
360        Instead, it keeps those local variables that need separate instances for
361        each "recursion" in a frame on the heap, and gets/frees frames whenever it
362        needs to "recurse". Keeping track of where control must go is done by means
363        of setjmp/longjmp. The whole thing is implemented by a set of macros that
364        hide most of the details from the main code, and operates only if
365        NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
366        "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
367        operating.
368    
369        To make it easier for callers to provide specially tailored get/free
370        functions for this usage, two new functions, pcre_stack_malloc, and
371        pcre_stack_free, are used. They are always called in strict stacking order,
372        and the size of block requested is always the same.
373    
374        The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
375        PCRE has been compiled to use the stack or the heap for recursion. The
376        -C option of pcretest uses this to show which version is compiled.
377    
378        A new data escape \S, is added to pcretest; it causes the amounts of store
379        obtained and freed by both kinds of malloc/free at match time to be added
380        to the output.
381    
382     2. Changed the locale test to use "fr_FR" instead of "fr" because that's
383        what's available on my current Linux desktop machine.
384    
385     3. When matching a UTF-8 string, the test for a valid string at the start has
386        been extended. If start_offset is not zero, PCRE now checks that it points
387        to a byte that is the start of a UTF-8 character. If not, it returns
388        PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
389        this is necessary because there may be backward assertions in the pattern.
390        When matching the same subject several times, it may save resources to use
391        PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
392    
393     4. The code for checking the validity of UTF-8 strings has been tightened so
394        that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
395        containing "overlong sequences".
396    
397     5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
398        I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
399        should have been "&", but it just so happened that all the cases this let
400        through by mistake were picked up later in the function.
401    
402     6. I had used a variable called "isblank" - this is a C99 function, causing
403        some compilers to warn. To avoid this, I renamed it (as "blankclass").
404    
405     7. Cosmetic: (a) only output another newline at the end of pcretest if it is
406        prompting; (b) run "./pcretest /dev/null" at the start of the test script
407        so the version is shown; (c) stop "make test" echoing "./RunTest".
408    
409     8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
410    
411     9. The prototype for memmove() for systems that don't have it was using
412        size_t, but the inclusion of the header that defines size_t was later. I've
413        moved the #includes for the C headers earlier to avoid this.
414    
415    10. Added some adjustments to the code to make it easier to compiler on certain
416        special systems:
417    
418          (a) Some "const" qualifiers were missing.
419          (b) Added the macro EXPORT before all exported functions; by default this
420              is defined to be empty.
421          (c) Changed the dftables auxiliary program (that builds chartables.c) so
422              that it reads its output file name as an argument instead of writing
423              to the standard output and assuming this can be redirected.
424    
425    11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
426        class containing characters with values greater than 255, PCRE compilation
427        went into a loop.
428    
429    12. A recursive reference to a subpattern that was within another subpattern
430        that had a minimum quantifier of zero caused PCRE to crash. For example,
431        (x(y(?2))z)? provoked this bug with a subject that got as far as the
432        recursion. If the recursively-called subpattern itself had a zero repeat,
433        that was OK.
434    
435    13. In pcretest, the buffer for reading a data line was set at 30K, but the
436        buffer into which it was copied (for escape processing) was still set at
437        1024, so long lines caused crashes.
438    
439    14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
440        "internal error: code overflow...". This applied to any character class
441        that was followed by a possessive quantifier.
442    
443    15. Modified the Makefile to add libpcre.la as a prerequisite for
444        libpcreposix.la because I was told this is needed for a parallel build to
445        work.
446    
447    16. If a pattern that contained .* following optional items at the start was
448        studied, the wrong optimizing data was generated, leading to matching
449        errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
450        matching string must start with a or b or c. The correct conclusion for
451        this pattern is that a match can start with any character.
452    
453    
454    Version 4.4 13-Aug-03
455    ---------------------
456    
457     1. In UTF-8 mode, a character class containing characters with values between
458        127 and 255 was not handled correctly if the compiled pattern was studied.
459        In fixing this, I have also improved the studying algorithm for such
460        classes (slightly).
461    
462     2. Three internal functions had redundant arguments passed to them. Removal
463        might give a very teeny performance improvement.
464    
465     3. Documentation bug: the value of the capture_top field in a callout is *one
466        more than* the number of the hightest numbered captured substring.
467    
468     4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
469        in incorrectly linking with a previously installed version. They now link
470        explicitly with libpcre.la.
471    
472     5. configure.in no longer needs to recognize Cygwin specially.
473    
474     6. A problem in pcre.in for Windows platforms is fixed.
475    
476     7. If a pattern was successfully studied, and the -d (or /D) flag was given to
477        pcretest, it used to include the size of the study block as part of its
478        output. Unfortunately, the structure contains a field that has a different
479        size on different hardware architectures. This meant that the tests that
480        showed this size failed. As the block is currently always of a fixed size,
481        this information isn't actually particularly useful in pcretest output, so
482        I have just removed it.
483    
484     8. Three pre-processor statements accidentally did not start in column 1.
485        Sadly, there are *still* compilers around that complain, even though
486        standard C has not required this for well over a decade. Sigh.
487    
488     9. In pcretest, the code for checking callouts passed small integers in the
489        callout_data field, which is a void * field. However, some picky compilers
490        complained about the casts involved for this on 64-bit systems. Now
491        pcretest passes the address of the small integer instead, which should get
492        rid of the warnings.
493    
494    10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
495        both compile and run time, and gives an error if an invalid UTF-8 sequence
496        is found. There is a option for disabling this check in cases where the
497        string is known to be correct and/or the maximum performance is wanted.
498    
499    11. In response to a bug report, I changed one line in Makefile.in from
500    
501            -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
502        to
503            -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
504    
505        to look similar to other lines, but I have no way of telling whether this
506        is the right thing to do, as I do not use Windows. No doubt I'll get told
507        if it's wrong...
508    
509    
510    Version 4.3 21-May-03
511    ---------------------
512    
513    1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
514       Makefile.
515    
516    2. Some refactoring to improve the quality of the code:
517    
518       (i)   The utf8_table... variables are now declared "const".
519    
520       (ii)  The code for \cx, which used the "case flipping" table to upper case
521             lower case letters, now just substracts 32. This is ASCII-specific,
522             but the whole concept of \cx is ASCII-specific, so it seems
523             reasonable.
524    
525       (iii) PCRE was using its character types table to recognize decimal and
526             hexadecimal digits in the pattern. This is silly, because it handles
527             only 0-9, a-f, and A-F, but the character types table is locale-
528             specific, which means strange things might happen. A private
529             table is now used for this - though it costs 256 bytes, a table is
530             much faster than multiple explicit tests. Of course, the standard
531             character types table is still used for matching digits in subject
532             strings against \d.
533    
534       (iv)  Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
535             ending in _t are). So I've renamed it as ESC_tee.
536    
537    3. The first argument for regexec() in the POSIX wrapper should have been
538       defined as "const".
539    
540    4. Changed pcretest to use malloc() for its buffers so that they can be
541       Electric Fenced for debugging.
542    
543    5. There were several places in the code where, in UTF-8 mode, PCRE would try
544       to read one or more bytes before the start of the subject string. Often this
545       had no effect on PCRE's behaviour, but in some circumstances it could
546       provoke a segmentation fault.
547    
548    6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
549       to try to read one or more bytes before the start of the subject string.
550    
551    7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
552       UTF-8 support could misbehave in various ways if the subject string
553       contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
554       area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
555       back over UTF-8 characters.)
556    
557    
558    Version 4.2 14-Apr-03
559    ---------------------
560    
561    1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
562    
563    2. Changes to the building process, supplied by Ronald Landheer-Cieslak
564         [ON_WINDOWS]: new variable, "#" on non-Windows platforms
565         [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
566         [WIN_PREFIX]: new variable, "cyg" for Cygwin
567         * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
568           and BUILD_EXEEXT
569         Note: automatic setting of the BUILD variables is not yet working
570         set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
571           compile-time but not at link-time
572         [LINK]: use for linking executables only
573         make different versions for Windows and non-Windows
574         [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
575           libraries
576         [LINK_FOR_BUILD]: new variable
577         [OBJEXT]: use throughout
578         [EXEEXT]: use throughout
579         <winshared>: new target
580         <wininstall>: new target
581         <dftables.o>: use native compiler
582         <dftables>: use native linker
583         <install>: handle Windows platform correctly
584         <clean>: ditto
585         <check>: ditto
586         copy DLL to top builddir before testing
587    
588       As part of these changes, -no-undefined was removed again. This was reported
589       to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
590       in any case.
591    
592    3. Some tidies to get rid of compiler warnings:
593    
594       . In the match_data structure, match_limit was an unsigned long int, whereas
595         match_call_count was an int. I've made them both unsigned long ints.
596    
597       . In pcretest the fact that a const uschar * doesn't automatically cast to
598         a void * provoked a warning.
599    
600       . Turning on some more compiler warnings threw up some "shadow" variables
601         and a few more missing casts.
602    
603    4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
604       option, a class that contained a single character with a value between 128
605       and 255 (e.g. /[\xFF]/) caused PCRE to crash.
606    
607    5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
608       option, a class that contained several characters, but with at least one
609       whose value was between 128 and 255 caused PCRE to crash.
610    
611    
612    Version 4.1 12-Mar-03
613    ---------------------
614    
615    1. Compiling with gcc -pedantic found a couple of places where casts were
616    needed, and a string in dftables.c that was longer than standard compilers are
617    required to support.
618    
619    2. Compiling with Sun's compiler found a few more places where the code could
620    be tidied up in order to avoid warnings.
621    
622    3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
623    first of these names is deprecated in the latest Autoconf in favour of the name
624    CC_FOR_BUILD, because "host" is typically used to mean the system on which the
625    compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
626    analogy I have changed it to CFLAGS_FOR_BUILD.
627    
628    4. Added -no-undefined to the linking command in the Makefile, because this is
629    apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
630    linking step for the pcreposix library.
631    
632    5. PCRE was failing to diagnose the case of two named groups with the same
633    name.
634    
635    6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
636    literal character that is needed in the subject for a match, and scans along to
637    ensure that it is present before embarking on the full matching process. This
638    saves time in cases of nested unlimited repeats that are never going to match.
639    Problem: the scan can take a lot of time if the subject is very long (e.g.
640    megabytes), thus penalizing straightforward matches. It is now done only if the
641    amount of subject to be scanned is less than 1000 bytes.
642    
643    7. A lesser problem with the same optimization is that it was recording the
644    first character of an anchored pattern as "needed", thus provoking a search
645    right along the subject, even when the first match of the pattern was going to
646    fail. The "needed" character is now not set for anchored patterns, unless it
647    follows something in the pattern that is of non-fixed length. Thus, it still
648    fulfils its original purpose of finding quick non-matches in cases of nested
649    unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
650    
651    
652    Version 4.0 17-Feb-03
653    ---------------------
654    
655    1. If a comment in an extended regex that started immediately after a meta-item
656    extended to the end of string, PCRE compiled incorrect data. This could lead to
657    all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
658    
659    2. Moved to autoconf 2.53 and libtool 1.4.2.
660    
661    3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
662    the special perltest8 script is no longer needed - all the tests can be run
663    from a single perltest script.
664    
665    4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
666    by \s. It has now been removed in PCRE. This means it isn't recognized as
667    whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
668    class [:space:] *does* include VT, thereby creating a mess.
669    
670    5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
671    space and tab.
672    
673    6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
674    its new features into the main test script, reducing the number of scripts.
675    
676    7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
677    were backward compatible, and made the (?i) apply to the whole pattern, as if
678    /i were given. Now it behaves more logically, and applies the option setting
679    only to what follows. PCRE has been changed to follow suit. However, if it
680    finds options settings right at the start of the pattern, it extracts them into
681    the global options, as before. Thus, they show up in the info data.
682    
683    8. Added support for the \Q...\E escape sequence. Characters in between are
684    treated as literals. This is slightly different from Perl in that $ and @ are
685    also handled as literals inside the quotes. In Perl, they will cause variable
686    interpolation. Note the following examples:
687    
688        Pattern            PCRE matches      Perl matches
689    
690        \Qabc$xyz\E        abc$xyz           abc followed by the contents of $xyz
691        \Qabc\$xyz\E       abc\$xyz          abc\$xyz
692        \Qabc\E\$\Qxyz\E   abc$xyz           abc$xyz
693    
694    For compatibility with Perl, \Q...\E sequences are recognized inside character
695    classes as well as outside them.
696    
697    9. Re-organized 3 code statements in pcretest to avoid "overflow in
698    floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
699    (size_t) cast to one statement in pcretest and one in pcreposix to avoid
700    signed/unsigned warnings.
701    
702    10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
703    option for pcretest, so I've replaced it by a simple function that does just
704    that job.
705    
706    11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
707    "pcregrep -".
708    
709    12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
710    Java package. This provides some syntactic sugar for simple cases of what my
711    documentation calls "once-only subpatterns". A pattern such as x*+ is the same
712    as (?>x*). In other words, if what is inside (?>...) is just a single repeated
713    item, you can use this simplified notation. Note that only makes sense with
714    greedy quantifiers. Consequently, the use of the possessive quantifier forces
715    greediness, whatever the setting of the PCRE_UNGREEDY option.
716    
717    13. A change of greediness default within a pattern was not taking effect at
718    the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
719    subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
720    was abstracted outside.
721    
722    14. PCRE now supports the \G assertion. It is true when the current matching
723    position is at the start point of the match. This differs from \A when the
724    starting offset is non-zero. Used with the /g option of pcretest (or similar
725    code), it works in the same way as it does for Perl's /g option. If all
726    alternatives of a regex begin with \G, the expression is anchored to the start
727    match position, and the "anchored" flag is set in the compiled expression.
728    
729    15. Some bugs concerning the handling of certain option changes within patterns
730    have been fixed. These applied to options other than (?ims). For example,
731    "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
732    been the other way round. Some of this was related to change 7 above.
733    
734    16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
735    features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
736    and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
737    POSIX classes only within a class (e.g. /[[:alpha:]]/).
738    
739    17. Added support for Perl's \C escape. This matches one byte, even in UTF8
740    mode. Unlike ".", it always matches newline, whatever the setting of
741    PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
742    assertions. Perl allows it, but it doesn't (in general) work because it can't
743    calculate the length of the lookbehind. At least, that's the case for Perl
744    5.8.0 - I've been told they are going to document that it doesn't work in
745    future.
746    
747    18. Added an error diagnosis for escapes that PCRE does not support: these are
748    \L, \l, \N, \P, \p, \U, \u, and \X.
749    
750    19. Although correctly diagnosing a missing ']' in a character class, PCRE was
751    reading past the end of the pattern in cases such as /[abcd/.
752    
753    20. PCRE was getting more memory than necessary for patterns with classes that
754    contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
755    
756    21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
757    compiling PCRE for use with Virtual Pascal.
758    
759    22. Small fix to the Makefile to make it work properly if the build is done
760    outside the source tree.
761    
762    23. Added a new extension: a condition to go with recursion. If a conditional
763    subpattern starts with (?(R) the "true" branch is used if recursion has
764    happened, whereas the "false" branch is used only at the top level.
765    
766    24. When there was a very long string of literal characters (over 255 bytes
767    without UTF support, over 250 bytes with UTF support), the computation of how
768    much memory was required could be incorrect, leading to segfaults or other
769    strange effects.
770    
771    25. PCRE was incorrectly assuming anchoring (either to start of subject or to
772    start of line for a non-DOTALL pattern) when a pattern started with (.*) and
773    there was a subsequent back reference to those brackets. This meant that, for
774    example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
775    possible to check for precisely this case. All we can do is abandon the
776    optimization if .* occurs inside capturing brackets when there are any back
777    references whatsoever. (See below for a better fix that came later.)
778    
779    26. The handling of the optimization for finding the first character of a
780    non-anchored pattern, and for finding a character that is required later in the
781    match were failing in some cases. This didn't break the matching; it just
782    failed to optimize when it could. The way this is done has been re-implemented.
783    
784    27. Fixed typo in error message for invalid (?R item (it said "(?p").
785    
786    28. Added a new feature that provides some of the functionality that Perl
787    provides with (?{...}). The facility is termed a "callout". The way it is done
788    in PCRE is for the caller to provide an optional function, by setting
789    pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
790    global variable. By default it is unset, which disables all calling out. To get
791    the function called, the regex must include (?C) at appropriate points. This
792    is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
793    This provides a means of identifying different callout points. When PCRE
794    reaches such a point in the regex, if pcre_callout has been set, the external
795    function is called. It is provided with data in a structure called
796    pcre_callout_block, which is defined in pcre.h. If the function returns 0,
797    matching continues; if it returns a non-zero value, the match at the current
798    point fails. However, backtracking will occur if possible. [This was changed
799    later and other features added - see item 49 below.]
800    
801    29. pcretest is upgraded to test the callout functionality. It provides a
802    callout function that displays information. By default, it shows the start of
803    the match and the current position in the text. There are some new data escapes
804    to vary what happens:
805    
806        \C+         in addition, show current contents of captured substrings
807        \C-         do not supply a callout function
808        \C!n        return 1 when callout number n is reached
809        \C!n!m      return 1 when callout number n is reached for the mth time
810    
811    30. If pcregrep was called with the -l option and just a single file name, it
812    output "<stdin>" if a match was found, instead of the file name.
813    
814    31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
815    slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
816    pcre_exec(). This saves a malloc/free per call. The default value of
817    POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
818    when configuring.
819    
820    32. The default maximum size of a compiled pattern is 64K. There have been a
821    few cases of people hitting this limit. The code now uses macros to handle the
822    storing of links as offsets within the compiled pattern. It defaults to 2-byte
823    links, but this can be changed to 3 or 4 bytes by --with-link-size when
824    configuring. Tests 2 and 5 work only with 2-byte links because they output
825    debugging information about compiled patterns.
826    
827    33. Internal code re-arrangements:
828    
829    (a) Moved the debugging function for printing out a compiled regex into
830        its own source file (printint.c) and used #include to pull it into
831        pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
832        separate copies.
833    
834    (b) Defined the list of op-code names for debugging as a macro in
835        internal.h so that it is next to the definition of the opcodes.
836    
837    (c) Defined a table of op-code lengths for simpler skipping along compiled
838        code. This is again a macro in internal.h so that it is next to the
839        definition of the opcodes.
840    
841    34. Added support for recursive calls to individual subpatterns, along the
842    lines of Robin Houston's patch (but implemented somewhat differently).
843    
844    35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
845    allow it to read and process whole directories in Win32. This code was
846    contributed by Lionel Fourquaux; it has not been tested by me.
847    
848    36. Added support for named subpatterns. The Python syntax (?P<name>...) is
849    used to name a group. Names consist of alphanumerics and underscores, and must
850    be unique. Back references use the syntax (?P=name) and recursive calls use
851    (?P>name) which is a PCRE extension to the Python extension. Groups still have
852    numbers. The function pcre_fullinfo() can be used after compilation to extract
853    a name/number map. There are three relevant calls:
854    
855      PCRE_INFO_NAMEENTRYSIZE        yields the size of each entry in the map
856      PCRE_INFO_NAMECOUNT            yields the number of entries
857      PCRE_INFO_NAMETABLE            yields a pointer to the map.
858    
859    The map is a vector of fixed-size entries. The size of each entry depends on
860    the length of the longest name used. The first two bytes of each entry are the
861    group number, most significant byte first. There follows the corresponding
862    name, zero terminated. The names are in alphabetical order.
863    
864    37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
865    case instead of 255. Making it the same both with and without UTF-8 support
866    means that the same test output works with both.
867    
868    38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
869    calling malloc() with a zero argument.
870    
871    39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
872    optimization. I've improved things by keeping a bitmap of backreferences with
873    numbers 1-31 so that if .* occurs inside capturing brackets that are not in
874    fact referenced, the optimization can be applied. It is unlikely that a
875    relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
876    the match to follow \n) will appear inside brackets with a number greater than
877    31, but if it does, any back reference > 31 suppresses the optimization.
878    
879    40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
880    of disabling numbered capturing parentheses. Any opening parenthesis that is
881    not followed by ? behaves as if it were followed by ?: but named parentheses
882    can still be used for capturing (and they will acquire numbers in the usual
883    way).
884    
885    41. Redesigned the return codes from the match() function into yes/no/error so
886    that errors can be passed back from deep inside the nested calls. A malloc
887    failure while inside a recursive subpattern call now causes the
888    PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
889    
890    42. It is now possible to set a limit on the number of times the match()
891    function is called in a call to pcre_exec(). This facility makes it possible to
892    limit the amount of recursion and backtracking, though not in a directly
893    obvious way, because the match() function is used in a number of different
894    circumstances. The count starts from zero for each position in the subject
895    string (for non-anchored patterns). The default limit is, for compatibility, a
896    large number, namely 10 000 000. You can change this in two ways:
897    
898    (a) When configuring PCRE before making, you can use --with-match-limit=n
899        to set a default value for the compiled library.
900    
901    (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
902        a different value is set. See 45 below.
903    
904    If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
905    
906    43. Added a new function pcre_config(int, void *) to enable run-time extraction
907    of things that can be changed at compile time. The first argument specifies
908    what is wanted and the second points to where the information is to be placed.
909    The current list of available information is:
910    
911      PCRE_CONFIG_UTF8
912    
913    The output is an integer that is set to one if UTF-8 support is available;
914    otherwise it is set to zero.
915    
916      PCRE_CONFIG_NEWLINE
917    
918    The output is an integer that it set to the value of the code that is used for
919    newline. It is either LF (10) or CR (13).
920    
921      PCRE_CONFIG_LINK_SIZE
922    
923    The output is an integer that contains the number of bytes used for internal
924    linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
925    
926      PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
927    
928    The output is an integer that contains the threshold above which the POSIX
929    interface uses malloc() for output vectors. See item 31 above.
930    
931      PCRE_CONFIG_MATCH_LIMIT
932    
933    The output is an unsigned integer that contains the default limit of the number
934    of match() calls in a pcre_exec() execution. See 42 above.
935    
936    44. pcretest has been upgraded by the addition of the -C option. This causes it
937    to extract all the available output from the new pcre_config() function, and to
938    output it. The program then exits immediately.
939    
940    45. A need has arisen to pass over additional data with calls to pcre_exec() in
941    order to support additional features. One way would have been to define
942    pcre_exec2() (for example) with extra arguments, but this would not have been
943    extensible, and would also have required all calls to the original function to
944    be mapped to the new one. Instead, I have chosen to extend the mechanism that
945    is used for passing in "extra" data from pcre_study().
946    
947    The pcre_extra structure is now exposed and defined in pcre.h. It currently
948    contains the following fields:
949    
950      flags         a bitmap indicating which of the following fields are set
951      study_data    opaque data from pcre_study()
952      match_limit   a way of specifying a limit on match() calls for a specific
953                      call to pcre_exec()
954      callout_data  data for callouts (see 49 below)
955    
956    The flag bits are also defined in pcre.h, and are
957    
958      PCRE_EXTRA_STUDY_DATA
959      PCRE_EXTRA_MATCH_LIMIT
960      PCRE_EXTRA_CALLOUT_DATA
961    
962    The pcre_study() function now returns one of these new pcre_extra blocks, with
963    the actual study data pointed to by the study_data field, and the
964    PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
965    before. That is, this change is entirely upwards-compatible and requires no
966    change to existing code.
967    
968    If you want to pass in additional data to pcre_exec(), you can either place it
969    in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
970    block.
971    
972    46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
973    data string contains the escape sequence \M, pcretest calls pcre_exec() several
974    times with different match limits, until it finds the minimum value needed for
975    pcre_exec() to complete. The value is then output. This can be instructive; for
976    most simple matches the number is quite small, but for pathological cases it
977    gets very large very quickly.
978    
979    47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
980    returns the size of the data block pointed to by the study_data field in a
981    pcre_extra block, that is, the value that was passed as the argument to
982    pcre_malloc() when PCRE was getting memory in which to place the information
983    created by pcre_study(). The fourth argument should point to a size_t variable.
984    pcretest has been extended so that this information is shown after a successful
985    pcre_study() call when information about the compiled regex is being displayed.
986    
987    48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
988    because what follows is always an absolute path. (Later: it turns out that this
989    is more than cosmetic for MinGW, because it doesn't like empty path
990    components.)
991    
992    49. Some changes have been made to the callout feature (see 28 above):
993    
994    (i)  A callout function now has three choices for what it returns:
995    
996           0  =>  success, carry on matching
997         > 0  =>  failure at this point, but backtrack if possible
998         < 0  =>  serious error, return this value from pcre_exec()
999    
1000         Negative values should normally be chosen from the set of PCRE_ERROR_xxx
1001         values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
1002         "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
1003         use by callout functions. It will never be used by PCRE itself.
1004    
1005    (ii) The pcre_extra structure (see 45 above) has a void * field called
1006         callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
1007         pcre_callout_block structure has a field of the same name. The contents of
1008         the field passed in the pcre_extra structure are passed to the callout
1009         function in the corresponding field in the callout block. This makes it
1010         easier to use the same callout-containing regex from multiple threads. For
1011         testing, the pcretest program has a new data escape
1012    
1013           \C*n        pass the number n (may be negative) as callout_data
1014    
1015         If the callout function in pcretest receives a non-zero value as
1016         callout_data, it returns that value.
1017    
1018    50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
1019    there were some redundant $(CFLAGS) in commands that are now specified as
1020    $(LINK), which already includes $(CFLAGS).
1021    
1022    51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
1023    has been compiled with UTF-8 support *and* pcre_compile() has been compiled
1024    with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
1025    one-byte characters throughout. Note that case-insensitive matching applies
1026    only to characters whose values are less than 256. PCRE doesn't support the
1027    notion of cases for higher-valued characters.
1028    
1029    (i)   A character class whose characters are all within 0-255 is handled as
1030          a bit map, and the map is inverted for negative classes. Previously, a
1031          character > 255 always failed to match such a class; however it should
1032          match if the class was a negative one (e.g. [^ab]). This has been fixed.
1033    
1034    (ii)  A negated character class with a single character < 255 is coded as
1035          "not this character" (OP_NOT). This wasn't working properly when the test
1036          character was multibyte, either singly or repeated.
1037    
1038    (iii) Repeats of multibyte characters are now handled correctly in UTF-8
1039          mode, for example: \x{100}{2,3}.
1040    
1041    (iv)  The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
1042          singly or repeated) now correctly test multibyte characters. However,
1043          PCRE doesn't recognize any characters with values greater than 255 as
1044          digits, spaces, or word characters. Such characters always match \D, \S,
1045          and \W, and never match \d, \s, or \w.
1046    
1047    (v)   Classes may now contain characters and character ranges with values
1048          greater than 255. For example: [ab\x{100}-\x{400}].
1049    
1050    (vi)  pcregrep now has a --utf-8 option (synonym -u) which makes it call
1051          PCRE in UTF-8 mode.
1052    
1053    52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
1054    PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
1055    retained for backwards compatibility. (Note that LASTLITERAL is also a byte
1056    value.)
1057    
1058    53. The single man page has become too large. I have therefore split it up into
1059    a number of separate man pages. These also give rise to individual HTML pages;
1060    these are now put in a separate directory, and there is an index.html page that
1061    lists them all. Some hyperlinking between the pages has been installed.
1062    
1063    54. Added convenience functions for handling named capturing parentheses.
1064    
1065    55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
1066    aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
1067    true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
1068    are faulted.
1069    
1070    56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
1071    calling configure. These values are used when compiling the dftables.c program
1072    which is run to generate the source of the default character tables. They
1073    default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
1074    you will need to set these values.
1075    
1076    57. Updated the building process for Windows DLL, as provided by Fred Cox.
1077    
1078    
1079    Version 3.9 02-Jan-02
1080    ---------------------
1081    
1082    1. A bit of extraneous text had somehow crept into the pcregrep documentation.
1083    
1084    2. If --disable-static was given, the building process failed when trying to
1085    build pcretest and pcregrep. (For some reason it was using libtool to compile
1086    them, which is not right, as they aren't part of the library.)
1087    
1088    
1089    Version 3.8 18-Dec-01
1090    ---------------------
1091    
1092    1. The experimental UTF-8 code was completely screwed up. It was packing the
1093    bytes in the wrong order. How dumb can you get?
1094    
1095    
1096    Version 3.7 29-Oct-01
1097    ---------------------
1098    
1099    1. In updating pcretest to check change 1 of version 3.6, I screwed up.
1100    This caused pcretest, when used on the test data, to segfault. Unfortunately,
1101    this didn't happen under Solaris 8, where I normally test things.
1102    
1103    2. The Makefile had to be changed to make it work on BSD systems, where 'make'
1104    doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
1105    isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
1106    this fix an hour or so after the initial 3.7 release.)
1107    
1108    
1109    Version 3.6 23-Oct-01
1110    ---------------------
1111    
1112    1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
1113    offsets passed as NULL with zero offset count.
1114    
1115    2. The config.guess and config.sub files had not been updated when I moved to
1116    the latest autoconf.
1117    
1118    
1119    Version 3.5 15-Aug-01
1120    ---------------------
1121    
1122    1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
1123    had been forgotten.
1124    
1125    2. By using declared but undefined structures, we can avoid using "void"
1126    definitions in pcre.h while keeping the internal definitions of the structures
1127    private.
1128    
1129    3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
1130    user point of view, this means that both static and shared libraries are built
1131    by default, but this can be individually controlled. More of the work of
1132    handling this static/shared cases is now inside libtool instead of PCRE's make
1133    file.
1134    
1135    4. The pcretest utility is now installed along with pcregrep because it is
1136    useful for users (to test regexs) and by doing this, it automatically gets
1137    relinked by libtool. The documentation has been turned into a man page, so
1138    there are now .1, .txt, and .html versions in /doc.
1139    
1140    5. Upgrades to pcregrep:
1141       (i)   Added long-form option names like gnu grep.
1142       (ii)  Added --help to list all options with an explanatory phrase.
1143       (iii) Added -r, --recursive to recurse into sub-directories.
1144       (iv)  Added -f, --file to read patterns from a file.
1145    
1146    6. pcre_exec() was referring to its "code" argument before testing that
1147    argument for NULL (and giving an error if it was NULL).
1148    
1149    7. Upgraded Makefile.in to allow for compiling in a different directory from
1150    the source directory.
1151    
1152    8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
1153    options bits, the pointer it was passed was to an int instead of to an unsigned
1154    long int. This mattered only on 64-bit systems.
1155    
1156    9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
1157    generated) instead of pcre.in, which it its source. Also made the same change
1158    in several of the .c files.
1159    
1160    10. A new release of gcc defines printf() as a macro, which broke pcretest
1161    because it had an ifdef in the middle of a string argument for printf(). Fixed
1162    by using separate calls to printf().
1163    
1164    11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
1165    script, to force use of CR or LF instead of \n in the source. On non-Unix
1166    systems, the value can be set in config.h.
1167    
1168    12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
1169    absolute limit. Changed the text of the error message to make this clear, and
1170    likewise updated the man page.
1171    
1172    13. The limit of 99 on the number of capturing subpatterns has been removed.
1173    The new limit is 65535, which I hope will not be a "real" limit.
1174    
1175    
1176    Version 3.4 22-Aug-00
1177    ---------------------
1178    
1179    1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
1180    
1181    2. Diagnose condition (?(0) as an error instead of crashing on matching.
1182    
1183    
1184    Version 3.3 01-Aug-00
1185    ---------------------
1186    
1187    1. If an octal character was given, but the value was greater than \377, it
1188    was not getting masked to the least significant bits, as documented. This could
1189    lead to crashes in some systems.
1190    
1191    2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
1192    the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
1193    
1194    3. Added the functions pcre_free_substring() and pcre_free_substring_list().
1195    These just pass their arguments on to (pcre_free)(), but they are provided
1196    because some uses of PCRE bind it to non-C systems that can call its functions,
1197    but cannot call free() or pcre_free() directly.
1198    
1199    4. Add "make test" as a synonym for "make check". Corrected some comments in
1200    the Makefile.
1201    
1202    5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
1203    Makefile.
1204    
1205    6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
1206    command called pgrep for grepping around the active processes.
1207    
1208    7. Added the beginnings of support for UTF-8 character strings.
1209    
1210    8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
1211    RANLIB to ./ltconfig so that they are used by libtool. I think these are all
1212    the relevant ones. (AR is not passed because ./ltconfig does its own figuring
1213    out for the ar command.)
1214    
1215    
1216    Version 3.2 12-May-00
1217    ---------------------
1218    
1219    This is purely a bug fixing release.
1220    
1221    1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
1222    of ZA. This was just one example of several cases that could provoke this bug,
1223    which was introduced by change 9 of version 2.00. The code for breaking
1224    infinite loops after an iteration that matches an empty string was't working
1225    correctly.
1226    
1227    2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
1228    when matched against abbab (for example). After matching an empty string, it
1229    wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
1230    caused it to match further down the string than it should.
1231    
1232    3. The code contained an inclusion of sys/types.h. It isn't clear why this
1233    was there because it doesn't seem to be needed, and it causes trouble on some
1234    systems, as it is not a Standard C header. It has been removed.
1235    
1236    4. Made 4 silly changes to the source to avoid stupid compiler warnings that
1237    were reported on the Macintosh. The changes were from
1238    
1239      while ((c = *(++ptr)) != 0 && c != '\n');
1240    to
1241      while ((c = *(++ptr)) != 0 && c != '\n') ;
1242    
1243    Totally extraordinary, but if that's what it takes...
1244    
1245    5. PCRE is being used in one environment where neither memmove() nor bcopy() is
1246    available. Added HAVE_BCOPY and an autoconf test for it; if neither
1247    HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
1248    assumes the way PCRE uses memmove() (always moving upwards).
1249    
1250    6. PCRE is being used in one environment where strchr() is not available. There
1251    was only one use in pcre.c, and writing it out to avoid strchr() probably gives
1252    faster code anyway.
1253    
1254    
1255    Version 3.1 09-Feb-00
1256    ---------------------
1257    
1258    The only change in this release is the fixing of some bugs in Makefile.in for
1259    the "install" target:
1260    
1261    (1) It was failing to install pcreposix.h.
1262    
1263    (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
1264    
1265    
1266    Version 3.0 01-Feb-00
1267    ---------------------
1268    
1269    1. Add support for the /+ modifier to perltest (to output $` like it does in
1270    pcretest).
1271    
1272    2. Add support for the /g modifier to perltest.
1273    
1274    3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
1275    matches null strings.
1276    
1277    4. Fix perltest so that it doesn't do unwanted things when fed an empty
1278    pattern. Perl treats empty patterns specially - it reuses the most recent
1279    pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
1280    effect.
1281    
1282    5. The POSIX interface was broken in that it was just handing over the POSIX
1283    captured string vector to pcre_exec(), but (since release 2.00) PCRE has
1284    required a bigger vector, with some working space on the end. This means that
1285    the POSIX wrapper now has to get and free some memory, and copy the results.
1286    
1287    6. Added some simple autoconf support, placing the test data and the
1288    documentation in separate directories, re-organizing some of the
1289    information files, and making it build pcre-config (a GNU standard). Also added
1290    libtool support for building PCRE as a shared library, which is now the
1291    default.
1292    
1293    7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
1294    09 are not valid octal constants. Single digits will be used for minor values
1295    less than 10.
1296    
1297    8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
1298    existing programs that set these in the POSIX interface can use PCRE without
1299    modification.
1300    
1301    9. Added a new function, pcre_fullinfo() with an extensible interface. It can
1302    return all that pcre_info() returns, plus additional data. The pcre_info()
1303    function is retained for compatibility, but is considered to be obsolete.
1304    
1305    10. Added experimental recursion feature (?R) to handle one common case that
1306    Perl 5.6 will be able to do with (?p{...}).
1307    
1308    11. Added support for POSIX character classes like [:alpha:], which Perl is
1309    adopting.
1310    
1311    
1312    Version 2.08 31-Aug-99
1313    ----------------------
1314    
1315    1. When startoffset was not zero and the pattern began with ".*", PCRE was not
1316    trying to match at the startoffset position, but instead was moving forward to
1317    the next newline as if a previous match had failed.
1318    
1319    2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
1320    and could get into a loop if a null string was matched other than at the start
1321    of the subject.
1322    
1323    3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
1324    be distinguished at compile time, and for completeness also added PCRE_DATE.
1325    
1326    5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
1327    in GnuWin32 environments.
1328    
1329    
1330  Version 2.07 29-Jul-99  Version 2.07 29-Jul-99
1331  ----------------------  ----------------------

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