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Revision 333 - (hide annotations) (download)
Thu Apr 10 19:55:57 2008 UTC (6 years, 3 months ago) by ph10
File size: 153110 byte(s)
Add Oniguruma syntax \g<...> and \g'...' for subroutine calls.

1 nigel 3 ChangeLog for PCRE
2     ------------------
3    
4 ph10 321 Version 7.7 05-Mar-08
5     ---------------------
6    
7     1. Applied Craig's patch to sort out a long long problem: "If we can't convert
8     a string to a long long, pretend we don't even have a long long." This is
9     done by checking for the strtoq, strtoll, and _strtoi64 functions.
10 ph10 322
11     2. Applied Craig's patch to pcrecpp.cc to restore ABI compatibility with
12     pre-7.6 versions, which defined a global no_arg variable instead of putting
13 ph10 332 it in the RE class. (See also #8 below.)
14 ph10 323
15     3. Remove a line of dead code, identified by coverity and reported by Nuno
16     Lopes.
17 ph10 324
18     4. Fixed two related pcregrep bugs involving -r with --include or --exclude:
19 ph10 321
20 ph10 324 (1) The include/exclude patterns were being applied to the whole pathnames
21     of files, instead of just to the final components.
22    
23     (2) If there was more than one level of directory, the subdirectories were
24     skipped unless they satisfied the include/exclude conditions. This is
25     inconsistent with GNU grep (and could even be seen as contrary to the
26     pcregrep specification - which I improved to make it absolutely clear).
27     The action now is always to scan all levels of directory, and just
28     apply the include/exclude patterns to regular files.
29 ph10 325
30     5. Added the --include_dir and --exclude_dir patterns to pcregrep, and used
31     --exclude_dir in the tests to avoid scanning .svn directories.
32 ph10 326
33     6. Applied Craig's patch to the QuoteMeta function so that it escapes the
34     NUL character as backslash + 0 rather than backslash + NUL, because PCRE
35     doesn't support NULs in patterns.
36 ph10 327
37     7. Added some missing "const"s to declarations of static tables in
38     pcre_compile.c and pcre_dfa_exec.c.
39 ph10 328
40     8. Applied Craig's patch to pcrecpp.cc to fix a problem in OS X that was
41 ph10 329 caused by fix #2 above. (Subsequently also a second patch to fix the
42 ph10 330 first patch. And a third patch - this was a messy problem.)
43 ph10 331
44     9. Applied Craig's patch to remove the use of push_back().
45 ph10 321
46 ph10 332 10. Applied Alan Lehotsky's patch to add REG_STARTEND support to the POSIX
47     matching function regexec().
48 ph10 333
49     11. Added support for the Oniguruma syntax \g<name>, \g<n>, \g'name', \g'n',
50     which, however, unlike Perl's \g{...}, are subroutine calls, not back
51     references. PCRE supports relative numbers with this syntax (I don't think
52     Oniguruma does).
53 ph10 324
54 ph10 332
55 ph10 319 Version 7.6 28-Jan-08
56 ph10 300 ---------------------
57    
58 ph10 302 1. A character class containing a very large number of characters with
59     codepoints greater than 255 (in UTF-8 mode, of course) caused a buffer
60     overflow.
61 ph10 309
62     2. Patch to cut out the "long long" test in pcrecpp_unittest when
63     HAVE_LONG_LONG is not defined.
64    
65 ph10 303 3. Applied Christian Ehrlicher's patch to update the CMake build files to
66 ph10 304 bring them up to date and include new features. This patch includes:
67 ph10 309
68 ph10 304 - Fixed PH's badly added libz and libbz2 support.
69     - Fixed a problem with static linking.
70 ph10 312 - Added pcredemo. [But later removed - see 7 below.]
71 ph10 304 - Fixed dftables problem and added an option.
72     - Added a number of HAVE_XXX tests, including HAVE_WINDOWS_H and
73     HAVE_LONG_LONG.
74     - Added readline support for pcretest.
75 ph10 309 - Added an listing of the option settings after cmake has run.
76    
77 ph10 314 4. A user submitted a patch to Makefile that makes it easy to create
78     "pcre.dll" under mingw when using Configure/Make. I added stuff to
79     Makefile.am that cause it to include this special target, without
80     affecting anything else. Note that the same mingw target plus all
81     the other distribution libraries and programs are now supported
82     when configuring with CMake (see 6 below) instead of with
83     Configure/Make.
84 ph10 309
85 ph10 308 5. Applied Craig's patch that moves no_arg into the RE class in the C++ code.
86     This is an attempt to solve the reported problem "pcrecpp::no_arg is not
87 ph10 309 exported in the Windows port". It has not yet been confirmed that the patch
88     solves the problem, but it does no harm.
89 ph10 313
90 ph10 311 6. Applied Sheri's patch to CMakeLists.txt to add NON_STANDARD_LIB_PREFIX and
91 ph10 319 NON_STANDARD_LIB_SUFFIX for dll names built with mingw when configured
92 ph10 314 with CMake, and also correct the comment about stack recursion.
93 ph10 313
94 ph10 312 7. Remove the automatic building of pcredemo from the ./configure system and
95 ph10 313 from CMakeLists.txt. The whole idea of pcredemo.c is that it is an example
96     of a program that users should build themselves after PCRE is installed, so
97     building it automatically is not really right. What is more, it gave
98 ph10 312 trouble in some build environments.
99 ph10 300
100 ph10 319 8. Further tidies to CMakeLists.txt from Sheri and Christian.
101 ph10 308
102 ph10 319
103 ph10 298 Version 7.5 10-Jan-08
104 ph10 263 ---------------------
105    
106     1. Applied a patch from Craig: "This patch makes it possible to 'ignore'
107     values in parens when parsing an RE using the C++ wrapper."
108 ph10 286
109 ph10 264 2. Negative specials like \S did not work in character classes in UTF-8 mode.
110     Characters greater than 255 were excluded from the class instead of being
111     included.
112 ph10 286
113     3. The same bug as (2) above applied to negated POSIX classes such as
114 ph10 265 [:^space:].
115 ph10 286
116 ph10 267 4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it
117     defined or documented. It seems to have been a typo for PCRE_STATIC, so
118 ph10 286 I have changed it.
119    
120 ph10 268 5. The construct (?&) was not diagnosed as a syntax error (it referenced the
121 ph10 286 first named subpattern) and a construct such as (?&a) would reference the
122     first named subpattern whose name started with "a" (in other words, the
123 ph10 272 length check was missing). Both these problems are fixed. "Subpattern name
124     expected" is now given for (?&) (a zero-length name), and this patch also
125     makes it give the same error for \k'' (previously it complained that that
126     was a reference to a non-existent subpattern).
127 ph10 286
128 ph10 269 6. The erroneous patterns (?+-a) and (?-+a) give different error messages;
129 ph10 286 this is right because (?- can be followed by option settings as well as by
130 ph10 269 digits. I have, however, made the messages clearer.
131 ph10 286
132 ph10 270 7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns
133     than the number used in the conditional) now cause a compile-time error.
134     This is actually not compatible with Perl, which accepts such patterns, but
135     treats the conditional as always being FALSE (as PCRE used to), but it
136     seems to me that giving a diagnostic is better.
137 ph10 286
138 ph10 274 8. Change "alphameric" to the more common word "alphanumeric" in comments
139 ph10 275 and messages.
140 ph10 286
141     9. Fix two occurrences of "backslash" in comments that should have been
142     "backspace".
143    
144     10. Remove two redundant lines of code that can never be obeyed (their function
145     was moved elsewhere).
146    
147     11. The program that makes PCRE's Unicode character property table had a bug
148     which caused it to generate incorrect table entries for sequences of
149 ph10 277 characters that have the same character type, but are in different scripts.
150 ph10 286 It amalgamated them into a single range, with the script of the first of
151 ph10 277 them. In other words, some characters were in the wrong script. There were
152     thirteen such cases, affecting characters in the following ranges:
153 ph10 286
154 ph10 277 U+002b0 - U+002c1
155     U+0060c - U+0060d
156 ph10 286 U+0061e - U+00612
157 ph10 277 U+0064b - U+0065e
158     U+0074d - U+0076d
159     U+01800 - U+01805
160     U+01d00 - U+01d77
161     U+01d9b - U+01dbf
162     U+0200b - U+0200f
163     U+030fc - U+030fe
164     U+03260 - U+0327f
165     U+0fb46 - U+0fbb1
166     U+10450 - U+1049d
167 ph10 286
168 ph10 279 12. The -o option (show only the matching part of a line) for pcregrep was not
169     compatible with GNU grep in that, if there was more than one match in a
170     line, it showed only the first of them. It now behaves in the same way as
171     GNU grep.
172 ph10 286
173     13. If the -o and -v options were combined for pcregrep, it printed a blank
174     line for every non-matching line. GNU grep prints nothing, and pcregrep now
175     does the same. The return code can be used to tell if there were any
176     non-matching lines.
177    
178 ph10 289 14. Added --file-offsets and --line-offsets to pcregrep.
179    
180     15. The pattern (?=something)(?R) was not being diagnosed as a potentially
181 ph10 282 infinitely looping recursion. The bug was that positive lookaheads were not
182 ph10 286 being skipped when checking for a possible empty match (negative lookaheads
183     and both kinds of lookbehind were skipped).
184    
185 ph10 289 16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the
186 ph10 284 inclusion of <windows.h> to before rather than after the definition of
187     INVALID_FILE_ATTRIBUTES (patch from David Byron).
188 ph10 263
189 ph10 289 17. Specifying a possessive quantifier with a specific limit for a Unicode
190 ph10 286 character property caused pcre_compile() to compile bad code, which led at
191     runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this
192     are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that
193     caused the error; without that there was no problem.
194 ph10 263
195 ph10 289 18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2.
196 ph10 286
197 ph10 289 19. Added --enable-pcretest-libreadline.
198 ph10 286
199 ph10 289 20. In pcrecpp.cc, the variable 'count' was incremented twice in
200 ph10 288 RE::GlobalReplace(). As a result, the number of replacements returned was
201 ph10 298 double what it should be. I removed one of the increments, but Craig sent a
202     later patch that removed the other one (the right fix) and added unit tests
203     that check the return values (which was not done before).
204 ph10 292
205 ph10 291 21. Several CMake things:
206 ph10 287
207 ph10 291 (1) Arranged that, when cmake is used on Unix, the libraries end up with
208 ph10 292 the names libpcre and libpcreposix, not just pcre and pcreposix.
209 ph10 288
210 ph10 292 (2) The above change means that pcretest and pcregrep are now correctly
211     linked with the newly-built libraries, not previously installed ones.
212 ph10 291
213 ph10 292 (3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2.
214 ph10 298
215     22. In UTF-8 mode, with newline set to "any", a pattern such as .*a.*=.b.*
216     crashed when matching a string such as a\x{2029}b (note that \x{2029} is a
217     UTF-8 newline character). The key issue is that the pattern starts .*;
218     this means that the match must be either at the beginning, or after a
219     newline. The bug was in the code for advancing after a failed match and
220     checking that the new position followed a newline. It was not taking
221 ph10 294 account of UTF-8 characters correctly.
222 ph10 298
223     23. PCRE was behaving differently from Perl in the way it recognized POSIX
224     character classes. PCRE was not treating the sequence [:...:] as a
225     character class unless the ... were all letters. Perl, however, seems to
226     allow any characters between [: and :], though of course it rejects as
227     unknown any "names" that contain non-letters, because all the known class
228     names consist only of letters. Thus, Perl gives an error for [[:1234:]],
229     for example, whereas PCRE did not - it did not recognize a POSIX character
230     class. This seemed a bit dangerous, so the code has been changed to be
231     closer to Perl. The behaviour is not identical to Perl, because PCRE will
232     diagnose an unknown class for, for example, [[:l\ower:]] where Perl will
233     treat it as [[:lower:]]. However, PCRE does now give "unknown" errors where
234     Perl does, and where it didn't before.
235    
236 ph10 296 24. Rewrite so as to remove the single use of %n from pcregrep because in some
237     Windows environments %n is disabled by default.
238 ph10 292
239    
240 ph10 260 Version 7.4 21-Sep-07
241 ph10 230 ---------------------
242    
243     1. Change 7.3/28 was implemented for classes by looking at the bitmap. This
244 ph10 231 means that a class such as [\s] counted as "explicit reference to CR or
245     LF". That isn't really right - the whole point of the change was to try to
246     help when there was an actual mention of one of the two characters. So now
247     the change happens only if \r or \n (or a literal CR or LF) character is
248 ph10 230 encountered.
249 ph10 231
250     2. The 32-bit options word was also used for 6 internal flags, but the numbers
251     of both had grown to the point where there were only 3 bits left.
252     Fortunately, there was spare space in the data structure, and so I have
253     moved the internal flags into a new 16-bit field to free up more option
254 ph10 230 bits.
255 ph10 231
256     3. The appearance of (?J) at the start of a pattern set the DUPNAMES option,
257     but did not set the internal JCHANGED flag - either of these is enough to
258     control the way the "get" function works - but the PCRE_INFO_JCHANGED
259     facility is supposed to tell if (?J) was ever used, so now (?J) at the
260 ph10 230 start sets both bits.
261    
262 ph10 231 4. Added options (at build time, compile time, exec time) to change \R from
263     matching any Unicode line ending sequence to just matching CR, LF, or CRLF.
264 ph10 230
265 ph10 243 5. doc/pcresyntax.html was missing from the distribution.
266    
267     6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward
268 ph10 233 compatibility, even though it is no longer used.
269 ph10 243
270     7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and
271 ph10 254 strtoull to pcrecpp.cc to select the available functions in WIN32 when the
272 ph10 259 windows.h file is present (where different names are used). [This was
273 ph10 257 reversed later after testing - see 16 below.]
274 ph10 243
275     8. Changed all #include <config.h> to #include "config.h". There were also
276 ph10 236 some further <pcre.h> cases that I changed to "pcre.h".
277 ph10 243
278 ph10 239 9. When pcregrep was used with the --colour option, it missed the line ending
279 ph10 243 sequence off the lines that it output.
280    
281     10. It was pointed out to me that arrays of string pointers cause lots of
282     relocations when a shared library is dynamically loaded. A technique of
283     using a single long string with a table of offsets can drastically reduce
284     these. I have refactored PCRE in four places to do this. The result is
285 ph10 240 dramatic:
286 ph10 243
287 ph10 240 Originally: 290
288     After changing UCP table: 187
289 ph10 243 After changing error message table: 43
290 ph10 240 After changing table of "verbs" 36
291     After changing table of Posix names 22
292 ph10 243
293 ph10 240 Thanks to the folks working on Gregex for glib for this insight.
294 ph10 247
295 ph10 244 11. --disable-stack-for-recursion caused compiling to fail unless -enable-
296 ph10 247 unicode-properties was also set.
297    
298 ph10 248 12. Updated the tests so that they work when \R is defaulted to ANYCRLF.
299 ph10 231
300 ph10 253 13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously
301     checked only for CRLF.
302 ph10 233
303 ph10 259 14. Added casts to pcretest.c to avoid compiler warnings.
304    
305 ph10 256 15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings.
306 ph10 253
307 ph10 257 16. Added Craig's patch to remove the WINDOWS_H tests, that were not working,
308 ph10 259 and instead check for _strtoi64 explicitly, and avoid the use of snprintf()
309     entirely. This removes changes made in 7 above.
310 ph10 256
311 ph10 261 17. The CMake files have been updated, and there is now more information about
312     building with CMake in the NON-UNIX-USE document.
313 ph10 257
314 ph10 261
315 ph10 228 Version 7.3 28-Aug-07
316 ph10 157 ---------------------
317    
318 ph10 189 1. In the rejigging of the build system that eventually resulted in 7.1, the
319     line "#include <pcre.h>" was included in pcre_internal.h. The use of angle
320     brackets there is not right, since it causes compilers to look for an
321     installed pcre.h, not the version that is in the source that is being
322     compiled (which of course may be different). I have changed it back to:
323 ph10 197
324 ph10 189 #include "pcre.h"
325 ph10 197
326     I have a vague recollection that the change was concerned with compiling in
327     different directories, but in the new build system, that is taken care of
328     by the VPATH setting the Makefile.
329    
330 ph10 190 2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed
331     when the subject happened to end in the byte 0x85 (e.g. if the last
332     character was \x{1ec5}). *Character* 0x85 is one of the "any" newline
333     characters but of course it shouldn't be taken as a newline when it is part
334     of another character. The bug was that, for an unlimited repeat of . in
335     not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by
336     characters when looking for a newline.
337 ph10 197
338     3. A small performance improvement in the DOTALL UTF-8 mode .* case.
339    
340     4. Debugging: adjusted the names of opcodes for different kinds of parentheses
341     in debug output.
342    
343 ph10 201 5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for
344     long printing in the pcrecpp unittest when running under MinGW.
345 ph10 189
346 ph10 197 6. ESC_K was left out of the EBCDIC table.
347 ph10 189
348 ph10 197 7. Change 7.0/38 introduced a new limit on the number of nested non-capturing
349     parentheses; I made it 1000, which seemed large enough. Unfortunately, the
350     limit also applies to "virtual nesting" when a pattern is recursive, and in
351     this case 1000 isn't so big. I have been able to remove this limit at the
352     expense of backing off one optimization in certain circumstances. Normally,
353     when pcre_exec() would call its internal match() function recursively and
354     immediately return the result unconditionally, it uses a "tail recursion"
355     feature to save stack. However, when a subpattern that can match an empty
356     string has an unlimited repetition quantifier, it no longer makes this
357     optimization. That gives it a stack frame in which to save the data for
358     checking that an empty string has been matched. Previously this was taken
359     from the 1000-entry workspace that had been reserved. So now there is no
360     explicit limit, but more stack is used.
361 ph10 189
362 ph10 200 8. Applied Daniel's patches to solve problems with the import/export magic
363     syntax that is required for Windows, and which was going wrong for the
364     pcreposix and pcrecpp parts of the library. These were overlooked when this
365     problem was solved for the main library.
366 ph10 197
367 ph10 202 9. There were some crude static tests to avoid integer overflow when computing
368     the size of patterns that contain repeated groups with explicit upper
369     limits. As the maximum quantifier is 65535, the maximum group length was
370     set at 30,000 so that the product of these two numbers did not overflow a
371     32-bit integer. However, it turns out that people want to use groups that
372     are longer than 30,000 bytes (though not repeat them that many times).
373     Change 7.0/17 (the refactoring of the way the pattern size is computed) has
374     made it possible to implement the integer overflow checks in a much more
375     dynamic way, which I have now done. The artificial limitation on group
376     length has been removed - we now have only the limit on the total length of
377     the compiled pattern, which depends on the LINK_SIZE setting.
378 ph10 208
379     10. Fixed a bug in the documentation for get/copy named substring when
380     duplicate names are permitted. If none of the named substrings are set, the
381     functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an
382     empty string.
383    
384     11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E
385     instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error,
386     because the ] is interpreted as the first data character and the
387     terminating ] is not found. PCRE has been made compatible with Perl in this
388     regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could
389     cause memory overwriting.
390    
391 ph10 206 10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty
392     string has been matched (to stop an infinite loop). It was not recognizing
393 ph10 208 a conditional subpattern that could match an empty string if that
394 ph10 206 subpattern was within another subpattern. For example, it looped when
395 ph10 208 trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the
396 ph10 206 condition was not nested. This bug has been fixed.
397 ph10 208
398 ph10 207 12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack
399     past the start of the subject in the presence of bytes with the top bit
400     set, for example "\x8aBCD".
401 ph10 211
402 ph10 210 13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE),
403     (*SKIP), (*THEN), (*COMMIT), and (*ACCEPT).
404 ph10 200
405 ph10 211 14. Optimized (?!) to (*FAIL).
406 ph10 202
407 ph10 212 15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629.
408     This restricts code points to be within the range 0 to 0x10FFFF, excluding
409     the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the
410     full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still
411     does: it's just the validity check that is more restrictive.
412 ph10 220
413     16. Inserted checks for integer overflows during escape sequence (backslash)
414     processing, and also fixed erroneous offset values for syntax errors during
415     backslash processing.
416    
417 ph10 214 17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above)
418 ph10 220 for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80".
419    
420 ph10 215 18. An unterminated class in a pattern like (?1)\c[ with a "forward reference"
421     caused an overrun.
422 ph10 220
423     19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with
424     something other than just ASCII characters) inside a group that had an
425     unlimited repeat caused a loop at compile time (while checking to see
426     whether the group could match an empty string).
427    
428 ph10 217 20. Debugging a pattern containing \p or \P could cause a crash. For example,
429     [\P{Any}] did so. (Error in the code for printing property names.)
430 ph10 210
431 ph10 220 21. An orphan \E inside a character class could cause a crash.
432    
433     22. A repeated capturing bracket such as (A)? could cause a wild memory
434 ph10 218 reference during compilation.
435 ph10 220
436     23. There are several functions in pcre_compile() that scan along a compiled
437     expression for various reasons (e.g. to see if it's fixed length for look
438 ph10 218 behind). There were bugs in these functions when a repeated \p or \P was
439 ph10 220 present in the pattern. These operators have additional parameters compared
440     with \d, etc, and these were not being taken into account when moving along
441 ph10 218 the compiled data. Specifically:
442 ph10 220
443     (a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed
444     length.
445    
446     (b) An item such as \pL+ within a repeated group could cause crashes or
447 ph10 218 loops.
448 ph10 220
449 ph10 218 (c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect
450 ph10 220 "reference to non-existent subpattern" error.
451    
452 ph10 221 (d) A pattern like (\P{Yi}{2}\277)? could loop at compile time.
453    
454 ph10 219 24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte
455 ph10 220 characters were involved (for example /\S{2}/8g with "A\x{a3}BC").
456 ph10 211
457 ph10 222 25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop.
458 ph10 218
459 ph10 227 26. Patterns such as [\P{Yi}A] which include \p or \P and just one other
460 ph10 223 character were causing crashes (broken optimization).
461 ph10 227
462 ph10 224 27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing
463 ph10 227 \p or \P) caused a compile-time loop.
464    
465 ph10 226 28. More problems have arisen in unanchored patterns when CRLF is a valid line
466     break. For example, the unstudied pattern [\r\n]A does not match the string
467     "\r\nA" because change 7.0/46 below moves the current point on by two
468     characters after failing to match at the start. However, the pattern \nA
469 ph10 227 *does* match, because it doesn't start till \n, and if [\r\n]A is studied,
470     the same is true. There doesn't seem any very clean way out of this, but
471     what I have chosen to do makes the common cases work: PCRE now takes note
472     of whether there can be an explicit match for \r or \n anywhere in the
473     pattern, and if so, 7.0/46 no longer applies. As part of this change,
474     there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled
475     pattern has explicit CR or LF references.
476 ph10 222
477 ph10 227 29. Added (*CR) etc for changing newline setting at start of pattern.
478 ph10 223
479 ph10 227
480 ph10 189 Version 7.2 19-Jun-07
481     ---------------------
482    
483 ph10 157 1. If the fr_FR locale cannot be found for test 3, try the "french" locale,
484     which is apparently normally available under Windows.
485 ph10 159
486     2. Re-jig the pcregrep tests with different newline settings in an attempt
487     to make them independent of the local environment's newline setting.
488 ph10 157
489 ph10 160 3. Add code to configure.ac to remove -g from the CFLAGS default settings.
490 ph10 165
491 ph10 161 4. Some of the "internals" tests were previously cut out when the link size
492     was not 2, because the output contained actual offsets. The recent new
493 ph10 165 "Z" feature of pcretest means that these can be cut out, making the tests
494     usable with all link sizes.
495    
496 ph10 164 5. Implemented Stan Switzer's goto replacement for longjmp() when not using
497     stack recursion. This gives a massive performance boost under BSD, but just
498 ph10 165 a small improvement under Linux. However, it saves one field in the frame
499 ph10 164 in all cases.
500 ph10 172
501 ph10 166 6. Added more features from the forthcoming Perl 5.10:
502 ph10 172
503 ph10 166 (a) (?-n) (where n is a string of digits) is a relative subroutine or
504     recursion call. It refers to the nth most recently opened parentheses.
505 ph10 172
506 ph10 166 (b) (?+n) is also a relative subroutine call; it refers to the nth next
507 ph10 172 to be opened parentheses.
508    
509     (c) Conditions that refer to capturing parentheses can be specified
510 ph10 167 relatively, for example, (?(-2)... or (?(+3)...
511 ph10 172
512 ph10 168 (d) \K resets the start of the current match so that everything before
513 ph10 172 is not part of it.
514    
515 ph10 171 (e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible).
516 ph10 172
517 ph10 171 (f) \g{name} is another synonym - part of Perl 5.10's unification of
518 ph10 172 reference syntax.
519 ph10 182
520 ph10 175 (g) (?| introduces a group in which the numbering of parentheses in each
521 ph10 182 alternative starts with the same number.
522 ph10 172
523 ph10 182 (h) \h, \H, \v, and \V match horizontal and vertical whitespace.
524    
525 ph10 172 7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and
526     PCRE_INFO_JCHANGED.
527    
528     8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not
529     terminating or by crashing. Diagnosed by Viktor Griph; it was in the code
530 ph10 170 for detecting groups that can match an empty string.
531 ph10 159
532 ph10 172 9. A pattern with a very large number of alternatives (more than several
533     hundred) was running out of internal workspace during the pre-compile
534     phase, where pcre_compile() figures out how much memory will be needed. A
535     bit of new cunning has reduced the workspace needed for groups with
536     alternatives. The 1000-alternative test pattern now uses 12 bytes of
537     workspace instead of running out of the 4096 that are available.
538 ph10 182
539 ph10 176 10. Inserted some missing (unsigned int) casts to get rid of compiler warnings.
540 ph10 172
541 ph10 179 11. Applied patch from Google to remove an optimization that didn't quite work.
542     The report of the bug said:
543 ph10 182
544 ph10 179 pcrecpp::RE("a*").FullMatch("aaa") matches, while
545     pcrecpp::RE("a*?").FullMatch("aaa") does not, and
546 ph10 182 pcrecpp::RE("a*?\\z").FullMatch("aaa") does again.
547 ph10 185
548 ph10 184 12. If \p or \P was used in non-UTF-8 mode on a character greater than 127
549 ph10 185 it matched the wrong number of bytes.
550 ph10 172
551 ph10 179
552 ph10 155 Version 7.1 24-Apr-07
553 ph10 98 ---------------------
554    
555 ph10 111 1. Applied Bob Rossi and Daniel G's patches to convert the build system to one
556 ph10 122 that is more "standard", making use of automake and other Autotools. There
557 ph10 99 is some re-arrangement of the files and adjustment of comments consequent
558     on this.
559 ph10 111
560     2. Part of the patch fixed a problem with the pcregrep tests. The test of -r
561     for recursive directory scanning broke on some systems because the files
562     are not scanned in any specific order and on different systems the order
563     was different. A call to "sort" has been inserted into RunGrepTest for the
564     approprate test as a short-term fix. In the longer term there may be an
565 ph10 100 alternative.
566 ph10 111
567 ph10 100 3. I had an email from Eric Raymond about problems translating some of PCRE's
568 ph10 111 man pages to HTML (despite the fact that I distribute HTML pages, some
569     people do their own conversions for various reasons). The problems
570     concerned the use of low-level troff macros .br and .in. I have therefore
571     removed all such uses from the man pages (some were redundant, some could
572 ph10 113 be replaced by .nf/.fi pairs). The 132html script that I use to generate
573     HTML has been updated to handle .nf/.fi and to complain if it encounters
574     .br or .in.
575 ph10 111
576 ph10 100 4. Updated comments in configure.ac that get placed in config.h.in and also
577 ph10 123 arranged for config.h to be included in the distribution, with the name
578 ph10 111 config.h.generic, for the benefit of those who have to compile without
579     Autotools (compare pcre.h, which is now distributed as pcre.h.generic).
580    
581     5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan
582     Weber: (1) pcre_internal.h was missing some function renames; (2) updated
583 ph10 127 makevp.bat for the current PCRE, using the additional files
584 ph10 135 makevp_c.txt, makevp_l.txt, and pcregexp.pas.
585 ph10 111
586     6. A Windows user reported a minor discrepancy with test 2, which turned out
587     to be caused by a trailing space on an input line that had got lost in his
588 ph10 102 copy. The trailing space was an accident, so I've just removed it.
589 ph10 111
590 ph10 104 7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told
591 ph10 111 that is needed.
592    
593 ph10 105 8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c)
594     as "const" (a) because they are and (b) because it helps the PHP
595     maintainers who have recently made a script to detect big data structures
596 ph10 111 in the php code that should be moved to the .rodata section. I remembered
597     to update Builducptable as well, so it won't revert if ucptable.h is ever
598 ph10 105 re-created.
599 ph10 111
600     9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c,
601 ph10 107 pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in
602 ph10 111 order to be able to cut out the UTF-8 tables in the latter when UTF-8
603     support is not required. This saves 1.5-2K of code, which is important in
604 ph10 107 some applications.
605 ph10 111
606 ph10 110 Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c
607 ph10 111 so as not to refer to the tables, even though these functions will never be
608     called when UTF-8 support is disabled. Otherwise there are problems with a
609     shared library.
610    
611 ph10 118 10. Fixed two bugs in the emulated memmove() function in pcre_internal.h:
612    
613     (a) It was defining its arguments as char * instead of void *.
614    
615 ph10 123 (b) It was assuming that all moves were upwards in memory; this was true
616     a long time ago when I wrote it, but is no longer the case.
617    
618 ph10 118 The emulated memove() is provided for those environments that have neither
619 ph10 123 memmove() nor bcopy(). I didn't think anyone used it these days, but that
620 ph10 118 is clearly not the case, as these two bugs were recently reported.
621 ph10 123
622 ph10 111 11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt,
623 ph10 123 and Detrail to create the HTML documentation, the .txt form of the man
624     pages, and it removes trailing spaces from listed files. It also creates
625     pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter
626     case, it wraps all the #defines with #ifndefs. This script should be run
627 ph10 111 before "make dist".
628 ph10 123
629 ph10 115 12. Fixed two fairly obscure bugs concerned with quantified caseless matching
630     with Unicode property support.
631 ph10 123
632     (a) For a maximizing quantifier, if the two different cases of the
633     character were of different lengths in their UTF-8 codings (there are
634     some cases like this - I found 11), and the matching function had to
635 ph10 115 back up over a mixture of the two cases, it incorrectly assumed they
636     were both the same length.
637 ph10 123
638     (b) When PCRE was configured to use the heap rather than the stack for
639     recursion during matching, it was not correctly preserving the data for
640     the other case of a UTF-8 character when checking ahead for a match
641     while processing a minimizing repeat. If the check also involved
642 ph10 115 matching a wide character, but failed, corruption could cause an
643     erroneous result when trying to check for a repeat of the original
644     character.
645 ph10 123
646 ph10 116 13. Some tidying changes to the testing mechanism:
647 ph10 98
648 ph10 116 (a) The RunTest script now detects the internal link size and whether there
649     is UTF-8 and UCP support by running ./pcretest -C instead of relying on
650 ph10 123 values substituted by "configure". (The RunGrepTest script already did
651     this for UTF-8.) The configure.ac script no longer substitutes the
652     relevant variables.
653    
654 ph10 116 (b) The debugging options /B and /D in pcretest show the compiled bytecode
655     with length and offset values. This means that the output is different
656     for different internal link sizes. Test 2 is skipped for link sizes
657     other than 2 because of this, bypassing the problem. Unfortunately,
658     there was also a test in test 3 (the locale tests) that used /B and
659 ph10 123 failed for link sizes other than 2. Rather than cut the whole test out,
660     I have added a new /Z option to pcretest that replaces the length and
661     offset values with spaces. This is now used to make test 3 independent
662 ph10 122 of link size. (Test 2 will be tidied up later.)
663 ph10 123
664     14. If erroroffset was passed as NULL to pcre_compile, it provoked a
665 ph10 122 segmentation fault instead of returning the appropriate error message.
666 ph10 134
667 ph10 131 15. In multiline mode when the newline sequence was set to "any", the pattern
668 ph10 134 ^$ would give a match between the \r and \n of a subject such as "A\r\nB".
669     This doesn't seem right; it now treats the CRLF combination as the line
670     ending, and so does not match in that case. It's only a pattern such as ^$
671     that would hit this one: something like ^ABC$ would have failed after \r
672     and then tried again after \r\n.
673    
674 ph10 131 16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub"
675 ph10 134 in an attempt to make files that differ only in their line terminators
676     compare equal. This works on Linux.
677 ph10 142
678 ph10 141 17. Under certain error circumstances pcregrep might try to free random memory
679     as it exited. This is now fixed, thanks to valgrind.
680 ph10 142
681 ph10 141 19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string
682 ph10 142 "abc\r\n\r\n", it found an unwanted second match after the second \r. This
683     was because its rules for how to advance for /g after matching an empty
684 ph10 143 string at the end of a line did not allow for this case. They now check for
685     it specially.
686 ph10 150
687     20. pcretest is supposed to handle patterns and data of any length, by
688     extending its buffers when necessary. It was getting this wrong when the
689 ph10 147 buffer for a data line had to be extended.
690 ph10 150
691 ph10 149 21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or
692 ph10 150 CRLF as a newline sequence.
693 ph10 152
694 ph10 151 22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut
695 ph10 152 out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but
696     I have nevertheless tidied it up.
697 ph10 111
698 ph10 152 23. Added some casts to kill warnings from HP-UX ia64 compiler.
699 ph10 123
700 ph10 153 24. Added a man page for pcre-config.
701 ph10 152
702 ph10 153
703 nigel 93 Version 7.0 19-Dec-06
704     ---------------------
705    
706     1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by
707     moving to gcc 4.1.1.
708    
709     2. The -S option for pcretest uses setrlimit(); I had omitted to #include
710     sys/time.h, which is documented as needed for this function. It doesn't
711     seem to matter on Linux, but it showed up on some releases of OS X.
712    
713     3. It seems that there are systems where bytes whose values are greater than
714     127 match isprint() in the "C" locale. The "C" locale should be the
715     default when a C program starts up. In most systems, only ASCII printing
716     characters match isprint(). This difference caused the output from pcretest
717     to vary, making some of the tests fail. I have changed pcretest so that:
718    
719     (a) When it is outputting text in the compiled version of a pattern, bytes
720     other than 32-126 are always shown as hex escapes.
721    
722     (b) When it is outputting text that is a matched part of a subject string,
723     it does the same, unless a different locale has been set for the match
724     (using the /L modifier). In this case, it uses isprint() to decide.
725    
726     4. Fixed a major bug that caused incorrect computation of the amount of memory
727     required for a compiled pattern when options that changed within the
728     pattern affected the logic of the preliminary scan that determines the
729     length. The relevant options are -x, and -i in UTF-8 mode. The result was
730     that the computed length was too small. The symptoms of this bug were
731     either the PCRE error "internal error: code overflow" from pcre_compile(),
732     or a glibc crash with a message such as "pcretest: free(): invalid next
733     size (fast)". Examples of patterns that provoked this bug (shown in
734     pcretest format) are:
735    
736     /(?-x: )/x
737     /(?x)(?-x: \s*#\s*)/
738     /((?i)[\x{c0}])/8
739     /(?i:[\x{c0}])/8
740    
741     HOWEVER: Change 17 below makes this fix obsolete as the memory computation
742     is now done differently.
743    
744     5. Applied patches from Google to: (a) add a QuoteMeta function to the C++
745     wrapper classes; (b) implement a new function in the C++ scanner that is
746     more efficient than the old way of doing things because it avoids levels of
747     recursion in the regex matching; (c) add a paragraph to the documentation
748     for the FullMatch() function.
749    
750     6. The escape sequence \n was being treated as whatever was defined as
751     "newline". Not only was this contrary to the documentation, which states
752     that \n is character 10 (hex 0A), but it also went horribly wrong when
753     "newline" was defined as CRLF. This has been fixed.
754    
755     7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c)
756     was being set to -1 for the "end of line" case (supposedly a value that no
757     character can have). Though this value is never used (the check for end of
758     line is "zero bytes in current character"), it caused compiler complaints.
759     I've changed it to 0xffffffff.
760    
761     8. In pcre_version.c, the version string was being built by a sequence of
762     C macros that, in the event of PCRE_PRERELEASE being defined as an empty
763     string (as it is for production releases) called a macro with an empty
764     argument. The C standard says the result of this is undefined. The gcc
765     compiler treats it as an empty string (which was what was wanted) but it is
766     reported that Visual C gives an error. The source has been hacked around to
767     avoid this problem.
768    
769     9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows
770     builds of pcretest, and changed the call to _setmode() to use _O_BINARY
771     instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all
772     of them did).
773    
774     10. Originally, pcretest opened its input and output without "b"; then I was
775     told that "b" was needed in some environments, so it was added for release
776     5.0 to both the input and output. (It makes no difference on Unix-like
777     systems.) Later I was told that it is wrong for the input on Windows. I've
778     now abstracted the modes into two macros, to make it easier to fiddle with
779     them, and removed "b" from the input mode under Windows.
780    
781     11. Added pkgconfig support for the C++ wrapper library, libpcrecpp.
782    
783     12. Added -help and --help to pcretest as an official way of being reminded
784     of the options.
785    
786     13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in
787     and pcrecpp.cc because they annoy compilers at high warning levels.
788    
789     14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop.
790    
791     15. Fixed an occurrence of == in configure.ac that should have been = (shell
792     scripts are not C programs :-) and which was not noticed because it works
793     on Linux.
794    
795     16. pcretest is supposed to handle any length of pattern and data line (as one
796     line or as a continued sequence of lines) by extending its input buffer if
797     necessary. This feature was broken for very long pattern lines, leading to
798     a string of junk being passed to pcre_compile() if the pattern was longer
799     than about 50K.
800    
801     17. I have done a major re-factoring of the way pcre_compile() computes the
802     amount of memory needed for a compiled pattern. Previously, there was code
803     that made a preliminary scan of the pattern in order to do this. That was
804     OK when PCRE was new, but as the facilities have expanded, it has become
805     harder and harder to keep it in step with the real compile phase, and there
806     have been a number of bugs (see for example, 4 above). I have now found a
807     cunning way of running the real compile function in a "fake" mode that
808     enables it to compute how much memory it would need, while actually only
809     ever using a few hundred bytes of working memory and without too many
810     tests of the mode. This should make future maintenance and development
811     easier. A side effect of this work is that the limit of 200 on the nesting
812     depth of parentheses has been removed (though this was never a serious
813     limitation, I suspect). However, there is a downside: pcre_compile() now
814     runs more slowly than before (30% or more, depending on the pattern). I
815     hope this isn't a big issue. There is no effect on runtime performance.
816    
817     18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a
818     newline (only possible for the last line of a file) and it was a
819     pattern that set a locale (followed by /Lsomething), pcretest crashed.
820    
821     19. Added additional timing features to pcretest. (1) The -tm option now times
822     matching only, not compiling. (2) Both -t and -tm can be followed, as a
823     separate command line item, by a number that specifies the number of
824     repeats to use when timing. The default is 50000; this gives better
825     precision, but takes uncomfortably long for very large patterns.
826    
827     20. Extended pcre_study() to be more clever in cases where a branch of a
828     subpattern has no definite first character. For example, (a*|b*)[cd] would
829     previously give no result from pcre_study(). Now it recognizes that the
830     first character must be a, b, c, or d.
831    
832     21. There was an incorrect error "recursive call could loop indefinitely" if
833     a subpattern (or the entire pattern) that was being tested for matching an
834     empty string contained only one non-empty item after a nested subpattern.
835     For example, the pattern (?>\x{100}*)\d(?R) provoked this error
836     incorrectly, because the \d was being skipped in the check.
837    
838     22. The pcretest program now has a new pattern option /B and a command line
839     option -b, which is equivalent to adding /B to every pattern. This causes
840     it to show the compiled bytecode, without the additional information that
841     -d shows. The effect of -d is now the same as -b with -i (and similarly, /D
842     is the same as /B/I).
843    
844     23. A new optimization is now able automatically to treat some sequences such
845     as a*b as a*+b. More specifically, if something simple (such as a character
846     or a simple class like \d) has an unlimited quantifier, and is followed by
847     something that cannot possibly match the quantified thing, the quantifier
848     is automatically "possessified".
849    
850     24. A recursive reference to a subpattern whose number was greater than 39
851     went wrong under certain circumstances in UTF-8 mode. This bug could also
852     have affected the operation of pcre_study().
853    
854     25. Realized that a little bit of performance could be had by replacing
855     (c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters.
856    
857     26. Timing data from pcretest is now shown to 4 decimal places instead of 3.
858    
859     27. Possessive quantifiers such as a++ were previously implemented by turning
860     them into atomic groups such as ($>a+). Now they have their own opcodes,
861     which improves performance. This includes the automatically created ones
862     from 23 above.
863    
864     28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a
865     lookahead was broken if it was not anchored. PCRE was mistakenly expecting
866     the first matched character to be a colon. This applied both to named and
867     numbered groups.
868    
869     29. The ucpinternal.h header file was missing its idempotency #ifdef.
870    
871     30. I was sent a "project" file called libpcre.a.dev which I understand makes
872     building PCRE on Windows easier, so I have included it in the distribution.
873    
874     31. There is now a check in pcretest against a ridiculously large number being
875     returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G
876     loop, the loop is abandoned.
877    
878     32. Forward references to subpatterns in conditions such as (?(2)...) where
879     subpattern 2 is defined later cause pcre_compile() to search forwards in
880     the pattern for the relevant set of parentheses. This search went wrong
881     when there were unescaped parentheses in a character class, parentheses
882     escaped with \Q...\E, or parentheses in a #-comment in /x mode.
883    
884     33. "Subroutine" calls and backreferences were previously restricted to
885     referencing subpatterns earlier in the regex. This restriction has now
886     been removed.
887    
888     34. Added a number of extra features that are going to be in Perl 5.10. On the
889     whole, these are just syntactic alternatives for features that PCRE had
890     previously implemented using the Python syntax or my own invention. The
891     other formats are all retained for compatibility.
892    
893     (a) Named groups can now be defined as (?<name>...) or (?'name'...) as well
894     as (?P<name>...). The new forms, as well as being in Perl 5.10, are
895     also .NET compatible.
896    
897     (b) A recursion or subroutine call to a named group can now be defined as
898     (?&name) as well as (?P>name).
899    
900     (c) A backreference to a named group can now be defined as \k<name> or
901     \k'name' as well as (?P=name). The new forms, as well as being in Perl
902     5.10, are also .NET compatible.
903    
904     (d) A conditional reference to a named group can now use the syntax
905     (?(<name>) or (?('name') as well as (?(name).
906    
907     (e) A "conditional group" of the form (?(DEFINE)...) can be used to define
908     groups (named and numbered) that are never evaluated inline, but can be
909     called as "subroutines" from elsewhere. In effect, the DEFINE condition
910     is always false. There may be only one alternative in such a group.
911    
912     (f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well
913     as the simple (?(R). The condition is true only if the most recent
914     recursion is that of the given number or name. It does not search out
915     through the entire recursion stack.
916    
917     (g) The escape \gN or \g{N} has been added, where N is a positive or
918     negative number, specifying an absolute or relative reference.
919    
920     35. Tidied to get rid of some further signed/unsigned compiler warnings and
921     some "unreachable code" warnings.
922    
923     36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other
924     things, this adds five new scripts.
925    
926     37. Perl ignores orphaned \E escapes completely. PCRE now does the same.
927     There were also incompatibilities regarding the handling of \Q..\E inside
928     character classes, for example with patterns like [\Qa\E-\Qz\E] where the
929     hyphen was adjacent to \Q or \E. I hope I've cleared all this up now.
930    
931     38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group
932     matches an empty string, and forcibly breaks the loop. There were bugs in
933     this code in non-simple cases. For a pattern such as ^(a()*)* matched
934     against aaaa the result was just "a" rather than "aaaa", for example. Two
935     separate and independent bugs (that affected different cases) have been
936     fixed.
937    
938     39. Refactored the code to abolish the use of different opcodes for small
939     capturing bracket numbers. This is a tidy that I avoided doing when I
940     removed the limit on the number of capturing brackets for 3.5 back in 2001.
941     The new approach is not only tidier, it makes it possible to reduce the
942     memory needed to fix the previous bug (38).
943    
944     40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline
945     sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when
946     processing dot, circumflex, or dollar metacharacters, or #-comments in /x
947     mode.
948    
949     41. Add \R to match any Unicode newline sequence, as suggested in the Unicode
950     report.
951    
952     42. Applied patch, originally from Ari Pollak, modified by Google, to allow
953     copy construction and assignment in the C++ wrapper.
954    
955     43. Updated pcregrep to support "--newline=any". In the process, I fixed a
956     couple of bugs that could have given wrong results in the "--newline=crlf"
957     case.
958    
959     44. Added a number of casts and did some reorganization of signed/unsigned int
960     variables following suggestions from Dair Grant. Also renamed the variable
961     "this" as "item" because it is a C++ keyword.
962    
963     45. Arranged for dftables to add
964    
965     #include "pcre_internal.h"
966    
967     to pcre_chartables.c because without it, gcc 4.x may remove the array
968     definition from the final binary if PCRE is built into a static library and
969     dead code stripping is activated.
970    
971     46. For an unanchored pattern, if a match attempt fails at the start of a
972     newline sequence, and the newline setting is CRLF or ANY, and the next two
973     characters are CRLF, advance by two characters instead of one.
974    
975    
976 nigel 91 Version 6.7 04-Jul-06
977     ---------------------
978    
979     1. In order to handle tests when input lines are enormously long, pcretest has
980     been re-factored so that it automatically extends its buffers when
981     necessary. The code is crude, but this _is_ just a test program. The
982     default size has been increased from 32K to 50K.
983    
984     2. The code in pcre_study() was using the value of the re argument before
985     testing it for NULL. (Of course, in any sensible call of the function, it
986     won't be NULL.)
987    
988     3. The memmove() emulation function in pcre_internal.h, which is used on
989     systems that lack both memmove() and bcopy() - that is, hardly ever -
990     was missing a "static" storage class specifier.
991    
992     4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns
993     containing an extended class (one that cannot be represented by a bitmap
994     because it contains high-valued characters or Unicode property items, e.g.
995     [\pZ]). Almost always one would set UTF-8 mode when processing such a
996     pattern, but PCRE should not loop if you do not (it no longer does).
997     [Detail: two cases were found: (a) a repeated subpattern containing an
998     extended class; (b) a recursive reference to a subpattern that followed a
999     previous extended class. It wasn't skipping over the extended class
1000     correctly when UTF-8 mode was not set.]
1001    
1002     5. A negated single-character class was not being recognized as fixed-length
1003     in lookbehind assertions such as (?<=[^f]), leading to an incorrect
1004     compile error "lookbehind assertion is not fixed length".
1005    
1006     6. The RunPerlTest auxiliary script was showing an unexpected difference
1007     between PCRE and Perl for UTF-8 tests. It turns out that it is hard to
1008     write a Perl script that can interpret lines of an input file either as
1009     byte characters or as UTF-8, which is what "perltest" was being required to
1010     do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you
1011     can't do is switch easily at run time between having the "use utf8;" pragma
1012     or not. In the end, I fudged it by using the RunPerlTest script to insert
1013     "use utf8;" explicitly for the UTF-8 tests.
1014    
1015     7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at
1016     the end of the subject string, contrary to the documentation and to what
1017     Perl does. This was true of both matching functions. Now it matches only at
1018     the start of the subject and immediately after *internal* newlines.
1019    
1020     8. A call of pcre_fullinfo() from pcretest to get the option bits was passing
1021     a pointer to an int instead of a pointer to an unsigned long int. This
1022     caused problems on 64-bit systems.
1023    
1024     9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another
1025     instance of the 'standard' template library not being so standard".
1026    
1027     10. There was no check on the number of named subpatterns nor the maximum
1028     length of a subpattern name. The product of these values is used to compute
1029     the size of the memory block for a compiled pattern. By supplying a very
1030     long subpattern name and a large number of named subpatterns, the size
1031     computation could be caused to overflow. This is now prevented by limiting
1032     the length of names to 32 characters, and the number of named subpatterns
1033     to 10,000.
1034    
1035     11. Subpatterns that are repeated with specific counts have to be replicated in
1036     the compiled pattern. The size of memory for this was computed from the
1037     length of the subpattern and the repeat count. The latter is limited to
1038     65535, but there was no limit on the former, meaning that integer overflow
1039     could in principle occur. The compiled length of a repeated subpattern is
1040     now limited to 30,000 bytes in order to prevent this.
1041    
1042     12. Added the optional facility to have named substrings with the same name.
1043    
1044     13. Added the ability to use a named substring as a condition, using the
1045     Python syntax: (?(name)yes|no). This overloads (?(R)... and names that
1046     are numbers (not recommended). Forward references are permitted.
1047    
1048     14. Added forward references in named backreferences (if you see what I mean).
1049    
1050     15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the
1051     pattern could run off the end of the subject. For example, the pattern
1052     "(?s)(.{1,5})"8 did this with the subject "ab".
1053    
1054     16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if
1055     PCRE_CASELESS was set when matching characters that were quantified with ?
1056     or *.
1057    
1058     17. A character class other than a single negated character that had a minimum
1059     but no maximum quantifier - for example [ab]{6,} - was not handled
1060     correctly by pce_dfa_exec(). It would match only one character.
1061    
1062     18. A valid (though odd) pattern that looked like a POSIX character
1063     class but used an invalid character after [ (for example [[,abc,]]) caused
1064     pcre_compile() to give the error "Failed: internal error: code overflow" or
1065     in some cases to crash with a glibc free() error. This could even happen if
1066     the pattern terminated after [[ but there just happened to be a sequence of
1067     letters, a binary zero, and a closing ] in the memory that followed.
1068    
1069     19. Perl's treatment of octal escapes in the range \400 to \777 has changed
1070     over the years. Originally (before any Unicode support), just the bottom 8
1071     bits were taken. Thus, for example, \500 really meant \100. Nowadays the
1072     output from "man perlunicode" includes this:
1073    
1074     The regular expression compiler produces polymorphic opcodes. That
1075     is, the pattern adapts to the data and automatically switches to
1076     the Unicode character scheme when presented with Unicode data--or
1077     instead uses a traditional byte scheme when presented with byte
1078     data.
1079    
1080     Sadly, a wide octal escape does not cause a switch, and in a string with
1081     no other multibyte characters, these octal escapes are treated as before.
1082     Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern
1083     /\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a
1084     Unicode string.
1085    
1086     I have not perpetrated such confusion in PCRE. Up till now, it took just
1087     the bottom 8 bits, as in old Perl. I have now made octal escapes with
1088     values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they
1089     translate to the appropriate multibyte character.
1090    
1091     29. Applied some refactoring to reduce the number of warnings from Microsoft
1092     and Borland compilers. This has included removing the fudge introduced
1093     seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused
1094     a warning about an unused variable.
1095    
1096     21. PCRE has not included VT (character 0x0b) in the set of whitespace
1097     characters since release 4.0, because Perl (from release 5.004) does not.
1098     [Or at least, is documented not to: some releases seem to be in conflict
1099     with the documentation.] However, when a pattern was studied with
1100     pcre_study() and all its branches started with \s, PCRE still included VT
1101     as a possible starting character. Of course, this did no harm; it just
1102     caused an unnecessary match attempt.
1103    
1104     22. Removed a now-redundant internal flag bit that recorded the fact that case
1105     dependency changed within the pattern. This was once needed for "required
1106     byte" processing, but is no longer used. This recovers a now-scarce options
1107     bit. Also moved the least significant internal flag bit to the most-
1108     significant bit of the word, which was not previously used (hangover from
1109     the days when it was an int rather than a uint) to free up another bit for
1110     the future.
1111    
1112     23. Added support for CRLF line endings as well as CR and LF. As well as the
1113     default being selectable at build time, it can now be changed at runtime
1114     via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to
1115     specify that it is scanning data with non-default line endings.
1116    
1117     24. Changed the definition of CXXLINK to make it agree with the definition of
1118     LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS.
1119    
1120     25. Applied Ian Taylor's patches to avoid using another stack frame for tail
1121     recursions. This makes a big different to stack usage for some patterns.
1122    
1123     26. If a subpattern containing a named recursion or subroutine reference such
1124     as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of
1125     the space required for the compiled pattern went wrong and gave too small a
1126     value. Depending on the environment, this could lead to "Failed: internal
1127     error: code overflow at offset 49" or "glibc detected double free or
1128     corruption" errors.
1129    
1130     27. Applied patches from Google (a) to support the new newline modes and (b) to
1131     advance over multibyte UTF-8 characters in GlobalReplace.
1132    
1133     28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a
1134     difference for some implementation of PCRE in some Windows version.
1135    
1136     29. Added some extra testing facilities to pcretest:
1137    
1138     \q<number> in a data line sets the "match limit" value
1139     \Q<number> in a data line sets the "match recursion limt" value
1140     -S <number> sets the stack size, where <number> is in megabytes
1141    
1142     The -S option isn't available for Windows.
1143    
1144    
1145 nigel 89 Version 6.6 06-Feb-06
1146     ---------------------
1147    
1148     1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined
1149     in pcreposix.h. I have copied the definition from pcre.h.
1150    
1151     2. Change 25 for 6.5 broke compilation in a build directory out-of-tree
1152     because pcre.h is no longer a built file.
1153    
1154     3. Added Jeff Friedl's additional debugging patches to pcregrep. These are
1155     not normally included in the compiled code.
1156    
1157    
1158 nigel 87 Version 6.5 01-Feb-06
1159     ---------------------
1160    
1161     1. When using the partial match feature with pcre_dfa_exec(), it was not
1162     anchoring the second and subsequent partial matches at the new starting
1163     point. This could lead to incorrect results. For example, with the pattern
1164     /1234/, partially matching against "123" and then "a4" gave a match.
1165    
1166     2. Changes to pcregrep:
1167    
1168     (a) All non-match returns from pcre_exec() were being treated as failures
1169     to match the line. Now, unless the error is PCRE_ERROR_NOMATCH, an
1170     error message is output. Some extra information is given for the
1171     PCRE_ERROR_MATCHLIMIT and PCRE_ERROR_RECURSIONLIMIT errors, which are
1172     probably the only errors that are likely to be caused by users (by
1173     specifying a regex that has nested indefinite repeats, for instance).
1174     If there are more than 20 of these errors, pcregrep is abandoned.
1175    
1176     (b) A binary zero was treated as data while matching, but terminated the
1177     output line if it was written out. This has been fixed: binary zeroes
1178     are now no different to any other data bytes.
1179    
1180     (c) Whichever of the LC_ALL or LC_CTYPE environment variables is set is
1181     used to set a locale for matching. The --locale=xxxx long option has
1182     been added (no short equivalent) to specify a locale explicitly on the
1183     pcregrep command, overriding the environment variables.
1184    
1185     (d) When -B was used with -n, some line numbers in the output were one less
1186     than they should have been.
1187    
1188     (e) Added the -o (--only-matching) option.
1189    
1190     (f) If -A or -C was used with -c (count only), some lines of context were
1191     accidentally printed for the final match.
1192    
1193     (g) Added the -H (--with-filename) option.
1194    
1195     (h) The combination of options -rh failed to suppress file names for files
1196     that were found from directory arguments.
1197    
1198     (i) Added the -D (--devices) and -d (--directories) options.
1199    
1200     (j) Added the -F (--fixed-strings) option.
1201    
1202     (k) Allow "-" to be used as a file name for -f as well as for a data file.
1203    
1204     (l) Added the --colo(u)r option.
1205    
1206     (m) Added Jeffrey Friedl's -S testing option, but within #ifdefs so that it
1207     is not present by default.
1208    
1209     3. A nasty bug was discovered in the handling of recursive patterns, that is,
1210     items such as (?R) or (?1), when the recursion could match a number of
1211     alternatives. If it matched one of the alternatives, but subsequently,
1212     outside the recursion, there was a failure, the code tried to back up into
1213     the recursion. However, because of the way PCRE is implemented, this is not
1214     possible, and the result was an incorrect result from the match.
1215    
1216     In order to prevent this happening, the specification of recursion has
1217     been changed so that all such subpatterns are automatically treated as
1218     atomic groups. Thus, for example, (?R) is treated as if it were (?>(?R)).
1219    
1220     4. I had overlooked the fact that, in some locales, there are characters for
1221     which isalpha() is true but neither isupper() nor islower() are true. In
1222     the fr_FR locale, for instance, the \xAA and \xBA characters (ordmasculine
1223     and ordfeminine) are like this. This affected the treatment of \w and \W
1224     when they appeared in character classes, but not when they appeared outside
1225     a character class. The bit map for "word" characters is now created
1226     separately from the results of isalnum() instead of just taking it from the
1227     upper, lower, and digit maps. (Plus the underscore character, of course.)
1228    
1229     5. The above bug also affected the handling of POSIX character classes such as
1230     [[:alpha:]] and [[:alnum:]]. These do not have their own bit maps in PCRE's
1231     permanent tables. Instead, the bit maps for such a class were previously
1232     created as the appropriate unions of the upper, lower, and digit bitmaps.
1233     Now they are created by subtraction from the [[:word:]] class, which has
1234     its own bitmap.
1235    
1236     6. The [[:blank:]] character class matches horizontal, but not vertical space.
1237     It is created by subtracting the vertical space characters (\x09, \x0a,
1238     \x0b, \x0c) from the [[:space:]] bitmap. Previously, however, the
1239     subtraction was done in the overall bitmap for a character class, meaning
1240     that a class such as [\x0c[:blank:]] was incorrect because \x0c would not
1241     be recognized. This bug has been fixed.
1242    
1243     7. Patches from the folks at Google:
1244    
1245     (a) pcrecpp.cc: "to handle a corner case that may or may not happen in
1246     real life, but is still worth protecting against".
1247    
1248     (b) pcrecpp.cc: "corrects a bug when negative radixes are used with
1249     regular expressions".
1250    
1251     (c) pcre_scanner.cc: avoid use of std::count() because not all systems
1252     have it.
1253    
1254     (d) Split off pcrecpparg.h from pcrecpp.h and had the former built by
1255     "configure" and the latter not, in order to fix a problem somebody had
1256     with compiling the Arg class on HP-UX.
1257    
1258     (e) Improve the error-handling of the C++ wrapper a little bit.
1259    
1260     (f) New tests for checking recursion limiting.
1261    
1262     8. The pcre_memmove() function, which is used only if the environment does not
1263     have a standard memmove() function (and is therefore rarely compiled),
1264     contained two bugs: (a) use of int instead of size_t, and (b) it was not
1265     returning a result (though PCRE never actually uses the result).
1266    
1267     9. In the POSIX regexec() interface, if nmatch is specified as a ridiculously
1268     large number - greater than INT_MAX/(3*sizeof(int)) - REG_ESPACE is
1269     returned instead of calling malloc() with an overflowing number that would
1270     most likely cause subsequent chaos.
1271    
1272     10. The debugging option of pcretest was not showing the NO_AUTO_CAPTURE flag.
1273    
1274     11. The POSIX flag REG_NOSUB is now supported. When a pattern that was compiled
1275     with this option is matched, the nmatch and pmatch options of regexec() are
1276     ignored.
1277    
1278     12. Added REG_UTF8 to the POSIX interface. This is not defined by POSIX, but is
1279     provided in case anyone wants to the the POSIX interface with UTF-8
1280     strings.
1281    
1282     13. Added CXXLDFLAGS to the Makefile parameters to provide settings only on the
1283     C++ linking (needed for some HP-UX environments).
1284    
1285     14. Avoid compiler warnings in get_ucpname() when compiled without UCP support
1286     (unused parameter) and in the pcre_printint() function (omitted "default"
1287     switch label when the default is to do nothing).
1288    
1289     15. Added some code to make it possible, when PCRE is compiled as a C++
1290     library, to replace subject pointers for pcre_exec() with a smart pointer
1291     class, thus making it possible to process discontinuous strings.
1292    
1293     16. The two macros PCRE_EXPORT and PCRE_DATA_SCOPE are confusing, and perform
1294     much the same function. They were added by different people who were trying
1295     to make PCRE easy to compile on non-Unix systems. It has been suggested
1296     that PCRE_EXPORT be abolished now that there is more automatic apparatus
1297     for compiling on Windows systems. I have therefore replaced it with
1298     PCRE_DATA_SCOPE. This is set automatically for Windows; if not set it
1299     defaults to "extern" for C or "extern C" for C++, which works fine on
1300     Unix-like systems. It is now possible to override the value of PCRE_DATA_
1301     SCOPE with something explicit in config.h. In addition:
1302    
1303     (a) pcreposix.h still had just "extern" instead of either of these macros;
1304     I have replaced it with PCRE_DATA_SCOPE.
1305    
1306     (b) Functions such as _pcre_xclass(), which are internal to the library,
1307     but external in the C sense, all had PCRE_EXPORT in their definitions.
1308     This is apparently wrong for the Windows case, so I have removed it.
1309     (It makes no difference on Unix-like systems.)
1310    
1311     17. Added a new limit, MATCH_LIMIT_RECURSION, which limits the depth of nesting
1312     of recursive calls to match(). This is different to MATCH_LIMIT because
1313     that limits the total number of calls to match(), not all of which increase
1314     the depth of recursion. Limiting the recursion depth limits the amount of
1315     stack (or heap if NO_RECURSE is set) that is used. The default can be set
1316     when PCRE is compiled, and changed at run time. A patch from Google adds
1317     this functionality to the C++ interface.
1318    
1319     18. Changes to the handling of Unicode character properties:
1320    
1321     (a) Updated the table to Unicode 4.1.0.
1322    
1323     (b) Recognize characters that are not in the table as "Cn" (undefined).
1324    
1325     (c) I revised the way the table is implemented to a much improved format
1326     which includes recognition of ranges. It now supports the ranges that
1327     are defined in UnicodeData.txt, and it also amalgamates other
1328     characters into ranges. This has reduced the number of entries in the
1329     table from around 16,000 to around 3,000, thus reducing its size
1330     considerably. I realized I did not need to use a tree structure after
1331     all - a binary chop search is just as efficient. Having reduced the
1332     number of entries, I extended their size from 6 bytes to 8 bytes to
1333     allow for more data.
1334    
1335     (d) Added support for Unicode script names via properties such as \p{Han}.
1336    
1337     19. In UTF-8 mode, a backslash followed by a non-Ascii character was not
1338     matching that character.
1339    
1340     20. When matching a repeated Unicode property with a minimum greater than zero,
1341     (for example \pL{2,}), PCRE could look past the end of the subject if it
1342     reached it while seeking the minimum number of characters. This could
1343     happen only if some of the characters were more than one byte long, because
1344     there is a check for at least the minimum number of bytes.
1345    
1346     21. Refactored the implementation of \p and \P so as to be more general, to
1347     allow for more different types of property in future. This has changed the
1348     compiled form incompatibly. Anybody with saved compiled patterns that use
1349     \p or \P will have to recompile them.
1350    
1351     22. Added "Any" and "L&" to the supported property types.
1352    
1353     23. Recognize \x{...} as a code point specifier, even when not in UTF-8 mode,
1354     but give a compile time error if the value is greater than 0xff.
1355    
1356     24. The man pages for pcrepartial, pcreprecompile, and pcre_compile2 were
1357     accidentally not being installed or uninstalled.
1358    
1359     25. The pcre.h file was built from pcre.h.in, but the only changes that were
1360     made were to insert the current release number. This seemed silly, because
1361     it made things harder for people building PCRE on systems that don't run
1362     "configure". I have turned pcre.h into a distributed file, no longer built
1363     by "configure", with the version identification directly included. There is
1364     no longer a pcre.h.in file.
1365    
1366     However, this change necessitated a change to the pcre-config script as
1367     well. It is built from pcre-config.in, and one of the substitutions was the
1368     release number. I have updated configure.ac so that ./configure now finds
1369     the release number by grepping pcre.h.
1370    
1371     26. Added the ability to run the tests under valgrind.
1372    
1373    
1374 nigel 85 Version 6.4 05-Sep-05
1375     ---------------------
1376    
1377     1. Change 6.0/10/(l) to pcregrep introduced a bug that caused separator lines
1378     "--" to be printed when multiple files were scanned, even when none of the
1379     -A, -B, or -C options were used. This is not compatible with Gnu grep, so I
1380     consider it to be a bug, and have restored the previous behaviour.
1381    
1382     2. A couple of code tidies to get rid of compiler warnings.
1383    
1384     3. The pcretest program used to cheat by referring to symbols in the library
1385     whose names begin with _pcre_. These are internal symbols that are not
1386     really supposed to be visible externally, and in some environments it is
1387     possible to suppress them. The cheating is now confined to including
1388     certain files from the library's source, which is a bit cleaner.
1389    
1390     4. Renamed pcre.in as pcre.h.in to go with pcrecpp.h.in; it also makes the
1391     file's purpose clearer.
1392    
1393     5. Reorganized pcre_ucp_findchar().
1394    
1395    
1396 nigel 83 Version 6.3 15-Aug-05
1397     ---------------------
1398    
1399     1. The file libpcre.pc.in did not have general read permission in the tarball.
1400    
1401     2. There were some problems when building without C++ support:
1402    
1403     (a) If C++ support was not built, "make install" and "make test" still
1404     tried to test it.
1405    
1406     (b) There were problems when the value of CXX was explicitly set. Some
1407     changes have been made to try to fix these, and ...
1408    
1409     (c) --disable-cpp can now be used to explicitly disable C++ support.
1410    
1411     (d) The use of @CPP_OBJ@ directly caused a blank line preceded by a
1412     backslash in a target when C++ was disabled. This confuses some
1413     versions of "make", apparently. Using an intermediate variable solves
1414     this. (Same for CPP_LOBJ.)
1415    
1416     3. $(LINK_FOR_BUILD) now includes $(CFLAGS_FOR_BUILD) and $(LINK)
1417     (non-Windows) now includes $(CFLAGS) because these flags are sometimes
1418     necessary on certain architectures.
1419    
1420     4. Added a setting of -export-symbols-regex to the link command to remove
1421     those symbols that are exported in the C sense, but actually are local
1422     within the library, and not documented. Their names all begin with
1423     "_pcre_". This is not a perfect job, because (a) we have to except some
1424     symbols that pcretest ("illegally") uses, and (b) the facility isn't always
1425     available (and never for static libraries). I have made a note to try to
1426     find a way round (a) in the future.
1427    
1428    
1429 nigel 81 Version 6.2 01-Aug-05
1430     ---------------------
1431    
1432     1. There was no test for integer overflow of quantifier values. A construction
1433     such as {1111111111111111} would give undefined results. What is worse, if
1434     a minimum quantifier for a parenthesized subpattern overflowed and became
1435     negative, the calculation of the memory size went wrong. This could have
1436     led to memory overwriting.
1437    
1438     2. Building PCRE using VPATH was broken. Hopefully it is now fixed.
1439    
1440     3. Added "b" to the 2nd argument of fopen() in dftables.c, for non-Unix-like
1441     operating environments where this matters.
1442    
1443     4. Applied Giuseppe Maxia's patch to add additional features for controlling
1444     PCRE options from within the C++ wrapper.
1445    
1446     5. Named capturing subpatterns were not being correctly counted when a pattern
1447     was compiled. This caused two problems: (a) If there were more than 100
1448     such subpatterns, the calculation of the memory needed for the whole
1449     compiled pattern went wrong, leading to an overflow error. (b) Numerical
1450     back references of the form \12, where the number was greater than 9, were
1451     not recognized as back references, even though there were sufficient
1452     previous subpatterns.
1453    
1454     6. Two minor patches to pcrecpp.cc in order to allow it to compile on older
1455     versions of gcc, e.g. 2.95.4.
1456    
1457    
1458 nigel 79 Version 6.1 21-Jun-05
1459     ---------------------
1460    
1461     1. There was one reference to the variable "posix" in pcretest.c that was not
1462     surrounded by "#if !defined NOPOSIX".
1463    
1464     2. Make it possible to compile pcretest without DFA support, UTF8 support, or
1465     the cross-check on the old pcre_info() function, for the benefit of the
1466     cut-down version of PCRE that is currently imported into Exim.
1467    
1468     3. A (silly) pattern starting with (?i)(?-i) caused an internal space
1469     allocation error. I've done the easy fix, which wastes 2 bytes for sensible
1470     patterns that start (?i) but I don't think that matters. The use of (?i) is
1471     just an example; this all applies to the other options as well.
1472    
1473     4. Since libtool seems to echo the compile commands it is issuing, the output
1474     from "make" can be reduced a bit by putting "@" in front of each libtool
1475     compile command.
1476    
1477     5. Patch from the folks at Google for configure.in to be a bit more thorough
1478     in checking for a suitable C++ installation before trying to compile the
1479     C++ stuff. This should fix a reported problem when a compiler was present,
1480     but no suitable headers.
1481    
1482     6. The man pages all had just "PCRE" as their title. I have changed them to
1483     be the relevant file name. I have also arranged that these names are
1484     retained in the file doc/pcre.txt, which is a concatenation in text format
1485     of all the man pages except the little individual ones for each function.
1486    
1487     7. The NON-UNIX-USE file had not been updated for the different set of source
1488     files that come with release 6. I also added a few comments about the C++
1489     wrapper.
1490    
1491    
1492 nigel 77 Version 6.0 07-Jun-05
1493     ---------------------
1494    
1495     1. Some minor internal re-organization to help with my DFA experiments.
1496    
1497     2. Some missing #ifdef SUPPORT_UCP conditionals in pcretest and printint that
1498     didn't matter for the library itself when fully configured, but did matter
1499     when compiling without UCP support, or within Exim, where the ucp files are
1500     not imported.
1501    
1502     3. Refactoring of the library code to split up the various functions into
1503     different source modules. The addition of the new DFA matching code (see
1504     below) to a single monolithic source would have made it really too
1505     unwieldy, quite apart from causing all the code to be include in a
1506     statically linked application, when only some functions are used. This is
1507     relevant even without the DFA addition now that patterns can be compiled in
1508     one application and matched in another.
1509    
1510     The downside of splitting up is that there have to be some external
1511     functions and data tables that are used internally in different modules of
1512     the library but which are not part of the API. These have all had their
1513     names changed to start with "_pcre_" so that they are unlikely to clash
1514     with other external names.
1515    
1516     4. Added an alternate matching function, pcre_dfa_exec(), which matches using
1517     a different (DFA) algorithm. Although it is slower than the original
1518     function, it does have some advantages for certain types of matching
1519     problem.
1520    
1521     5. Upgrades to pcretest in order to test the features of pcre_dfa_exec(),
1522     including restarting after a partial match.
1523    
1524     6. A patch for pcregrep that defines INVALID_FILE_ATTRIBUTES if it is not
1525     defined when compiling for Windows was sent to me. I have put it into the
1526     code, though I have no means of testing or verifying it.
1527    
1528     7. Added the pcre_refcount() auxiliary function.
1529    
1530     8. Added the PCRE_FIRSTLINE option. This constrains an unanchored pattern to
1531     match before or at the first newline in the subject string. In pcretest,
1532     the /f option on a pattern can be used to set this.
1533    
1534     9. A repeated \w when used in UTF-8 mode with characters greater than 256
1535     would behave wrongly. This has been present in PCRE since release 4.0.
1536    
1537     10. A number of changes to the pcregrep command:
1538    
1539     (a) Refactored how -x works; insert ^(...)$ instead of setting
1540     PCRE_ANCHORED and checking the length, in preparation for adding
1541     something similar for -w.
1542    
1543     (b) Added the -w (match as a word) option.
1544    
1545     (c) Refactored the way lines are read and buffered so as to have more
1546     than one at a time available.
1547    
1548     (d) Implemented a pcregrep test script.
1549    
1550     (e) Added the -M (multiline match) option. This allows patterns to match
1551     over several lines of the subject. The buffering ensures that at least
1552     8K, or the rest of the document (whichever is the shorter) is available
1553     for matching (and similarly the previous 8K for lookbehind assertions).
1554    
1555     (f) Changed the --help output so that it now says
1556    
1557     -w, --word-regex(p)
1558    
1559     instead of two lines, one with "regex" and the other with "regexp"
1560     because that confused at least one person since the short forms are the
1561     same. (This required a bit of code, as the output is generated
1562     automatically from a table. It wasn't just a text change.)
1563    
1564     (g) -- can be used to terminate pcregrep options if the next thing isn't an
1565     option but starts with a hyphen. Could be a pattern or a path name
1566     starting with a hyphen, for instance.
1567    
1568     (h) "-" can be given as a file name to represent stdin.
1569    
1570     (i) When file names are being printed, "(standard input)" is used for
1571     the standard input, for compatibility with GNU grep. Previously
1572     "<stdin>" was used.
1573    
1574     (j) The option --label=xxx can be used to supply a name to be used for
1575     stdin when file names are being printed. There is no short form.
1576    
1577     (k) Re-factored the options decoding logic because we are going to add
1578     two more options that take data. Such options can now be given in four
1579     different ways, e.g. "-fname", "-f name", "--file=name", "--file name".
1580    
1581     (l) Added the -A, -B, and -C options for requesting that lines of context
1582     around matches be printed.
1583    
1584     (m) Added the -L option to print the names of files that do not contain
1585     any matching lines, that is, the complement of -l.
1586    
1587     (n) The return code is 2 if any file cannot be opened, but pcregrep does
1588     continue to scan other files.
1589    
1590     (o) The -s option was incorrectly implemented. For compatibility with other
1591     greps, it now suppresses the error message for a non-existent or non-
1592     accessible file (but not the return code). There is a new option called
1593     -q that suppresses the output of matching lines, which was what -s was
1594     previously doing.
1595    
1596     (p) Added --include and --exclude options to specify files for inclusion
1597     and exclusion when recursing.
1598    
1599     11. The Makefile was not using the Autoconf-supported LDFLAGS macro properly.
1600     Hopefully, it now does.
1601    
1602     12. Missing cast in pcre_study().
1603    
1604     13. Added an "uninstall" target to the makefile.
1605    
1606     14. Replaced "extern" in the function prototypes in Makefile.in with
1607     "PCRE_DATA_SCOPE", which defaults to 'extern' or 'extern "C"' in the Unix
1608     world, but is set differently for Windows.
1609    
1610     15. Added a second compiling function called pcre_compile2(). The only
1611     difference is that it has an extra argument, which is a pointer to an
1612     integer error code. When there is a compile-time failure, this is set
1613     non-zero, in addition to the error test pointer being set to point to an
1614     error message. The new argument may be NULL if no error number is required
1615     (but then you may as well call pcre_compile(), which is now just a
1616     wrapper). This facility is provided because some applications need a
1617     numeric error indication, but it has also enabled me to tidy up the way
1618     compile-time errors are handled in the POSIX wrapper.
1619    
1620     16. Added VPATH=.libs to the makefile; this should help when building with one
1621     prefix path and installing with another. (Or so I'm told by someone who
1622     knows more about this stuff than I do.)
1623    
1624     17. Added a new option, REG_DOTALL, to the POSIX function regcomp(). This
1625     passes PCRE_DOTALL to the pcre_compile() function, making the "." character
1626     match everything, including newlines. This is not POSIX-compatible, but
1627     somebody wanted the feature. From pcretest it can be activated by using
1628     both the P and the s flags.
1629    
1630     18. AC_PROG_LIBTOOL appeared twice in Makefile.in. Removed one.
1631    
1632     19. libpcre.pc was being incorrectly installed as executable.
1633    
1634     20. A couple of places in pcretest check for end-of-line by looking for '\n';
1635     it now also looks for '\r' so that it will work unmodified on Windows.
1636    
1637     21. Added Google's contributed C++ wrapper to the distribution.
1638    
1639     22. Added some untidy missing memory free() calls in pcretest, to keep
1640     Electric Fence happy when testing.
1641    
1642    
1643    
1644 nigel 75 Version 5.0 13-Sep-04
1645     ---------------------
1646    
1647     1. Internal change: literal characters are no longer packed up into items
1648     containing multiple characters in a single byte-string. Each character
1649     is now matched using a separate opcode. However, there may be more than one
1650     byte in the character in UTF-8 mode.
1651    
1652     2. The pcre_callout_block structure has two new fields: pattern_position and
1653     next_item_length. These contain the offset in the pattern to the next match
1654     item, and its length, respectively.
1655    
1656     3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
1657     insertion of callouts before each pattern item. Added the /C option to
1658     pcretest to make use of this.
1659    
1660     4. On the advice of a Windows user, the lines
1661    
1662     #if defined(_WIN32) || defined(WIN32)
1663     _setmode( _fileno( stdout ), 0x8000 );
1664     #endif /* defined(_WIN32) || defined(WIN32) */
1665    
1666     have been added to the source of pcretest. This apparently does useful
1667     magic in relation to line terminators.
1668    
1669     5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
1670     for the benefit of those environments where the "b" makes a difference.
1671    
1672     6. The icc compiler has the same options as gcc, but "configure" doesn't seem
1673     to know about it. I have put a hack into configure.in that adds in code
1674     to set GCC=yes if CC=icc. This seems to end up at a point in the
1675     generated configure script that is early enough to affect the setting of
1676     compiler options, which is what is needed, but I have no means of testing
1677     whether it really works. (The user who reported this had patched the
1678     generated configure script, which of course I cannot do.)
1679    
1680     LATER: After change 22 below (new libtool files), the configure script
1681     seems to know about icc (and also ecc). Therefore, I have commented out
1682     this hack in configure.in.
1683    
1684     7. Added support for pkg-config (2 patches were sent in).
1685    
1686     8. Negated POSIX character classes that used a combination of internal tables
1687     were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
1688     [[:^ascii]]. Typically, they would match almost any characters. The other
1689     POSIX classes were not broken in this way.
1690    
1691     9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
1692     to find the match, as PCRE was deluded into thinking that the match had to
1693     start at the start point or following a newline. The same bug applied to
1694     patterns with negative forward assertions or any backward assertions
1695     preceding ".*" at the start, unless the pattern required a fixed first
1696     character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
1697    
1698     10. In UTF-8 mode, when moving forwards in the subject after a failed match
1699     starting at the last subject character, bytes beyond the end of the subject
1700     string were read.
1701    
1702     11. Renamed the variable "class" as "classbits" to make life easier for C++
1703     users. (Previously there was a macro definition, but it apparently wasn't
1704     enough.)
1705    
1706     12. Added the new field "tables" to the extra data so that tables can be passed
1707     in at exec time, or the internal tables can be re-selected. This allows
1708     a compiled regex to be saved and re-used at a later time by a different
1709     program that might have everything at different addresses.
1710    
1711     13. Modified the pcre-config script so that, when run on Solaris, it shows a
1712     -R library as well as a -L library.
1713    
1714     14. The debugging options of pcretest (-d on the command line or D on a
1715     pattern) showed incorrect output for anything following an extended class
1716     that contained multibyte characters and which was followed by a quantifier.
1717    
1718     15. Added optional support for general category Unicode character properties
1719     via the \p, \P, and \X escapes. Unicode property support implies UTF-8
1720     support. It adds about 90K to the size of the library. The meanings of the
1721     inbuilt class escapes such as \d and \s have NOT been changed.
1722    
1723     16. Updated pcredemo.c to include calls to free() to release the memory for the
1724     compiled pattern.
1725    
1726     17. The generated file chartables.c was being created in the source directory
1727     instead of in the building directory. This caused the build to fail if the
1728     source directory was different from the building directory, and was
1729     read-only.
1730    
1731     18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
1732     file. No doubt somebody will tell me if they don't make sense... Also added
1733     Dan Mooney's comments about building on OpenVMS.
1734    
1735     19. Added support for partial matching via the PCRE_PARTIAL option for
1736     pcre_exec() and the \P data escape in pcretest.
1737    
1738     20. Extended pcretest with 3 new pattern features:
1739    
1740     (i) A pattern option of the form ">rest-of-line" causes pcretest to
1741     write the compiled pattern to the file whose name is "rest-of-line".
1742     This is a straight binary dump of the data, with the saved pointer to
1743     the character tables forced to be NULL. The study data, if any, is
1744     written too. After writing, pcretest reads a new pattern.
1745    
1746     (ii) If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
1747     compiled pattern from the given file. There must not be any
1748     occurrences of "<" in the file name (pretty unlikely); if there are,
1749     pcretest will instead treat the initial "<" as a pattern delimiter.
1750     After reading in the pattern, pcretest goes on to read data lines as
1751     usual.
1752    
1753     (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
1754     and 16-bit fields in a compiled pattern, to simulate a pattern that
1755     was compiled on a host of opposite endianness.
1756    
1757     21. The pcre-exec() function can now cope with patterns that were compiled on
1758     hosts of opposite endianness, with this restriction:
1759    
1760     As for any compiled expression that is saved and used later, the tables
1761     pointer field cannot be preserved; the extra_data field in the arguments
1762     to pcre_exec() should be used to pass in a tables address if a value
1763     other than the default internal tables were used at compile time.
1764    
1765     22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
1766     now diagnosed as an error. Previously, most of the time, a negative number
1767     would have been treated as zero, but if in addition "ovector" was passed as
1768     NULL, a crash could occur.
1769    
1770     23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
1771     new versions from the libtool 1.5 distribution (the last one is a copy of
1772     a file called libtool.m4). This seems to have fixed the need to patch
1773     "configure" to support Darwin 1.3 (which I used to do). However, I still
1774     had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
1775     workstation).
1776    
1777     24. Changed the PCRE licence to be the more standard "BSD" licence.
1778    
1779    
1780 nigel 73 Version 4.5 01-Dec-03
1781     ---------------------
1782    
1783     1. There has been some re-arrangement of the code for the match() function so
1784     that it can be compiled in a version that does not call itself recursively.
1785     Instead, it keeps those local variables that need separate instances for
1786     each "recursion" in a frame on the heap, and gets/frees frames whenever it
1787     needs to "recurse". Keeping track of where control must go is done by means
1788     of setjmp/longjmp. The whole thing is implemented by a set of macros that
1789     hide most of the details from the main code, and operates only if
1790     NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
1791     "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
1792     operating.
1793    
1794     To make it easier for callers to provide specially tailored get/free
1795     functions for this usage, two new functions, pcre_stack_malloc, and
1796     pcre_stack_free, are used. They are always called in strict stacking order,
1797     and the size of block requested is always the same.
1798    
1799     The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
1800     PCRE has been compiled to use the stack or the heap for recursion. The
1801     -C option of pcretest uses this to show which version is compiled.
1802    
1803     A new data escape \S, is added to pcretest; it causes the amounts of store
1804     obtained and freed by both kinds of malloc/free at match time to be added
1805     to the output.
1806    
1807     2. Changed the locale test to use "fr_FR" instead of "fr" because that's
1808     what's available on my current Linux desktop machine.
1809    
1810     3. When matching a UTF-8 string, the test for a valid string at the start has
1811     been extended. If start_offset is not zero, PCRE now checks that it points
1812     to a byte that is the start of a UTF-8 character. If not, it returns
1813     PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
1814     this is necessary because there may be backward assertions in the pattern.
1815     When matching the same subject several times, it may save resources to use
1816     PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
1817    
1818     4. The code for checking the validity of UTF-8 strings has been tightened so
1819     that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
1820     containing "overlong sequences".
1821    
1822     5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
1823     I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
1824     should have been "&", but it just so happened that all the cases this let
1825     through by mistake were picked up later in the function.
1826    
1827     6. I had used a variable called "isblank" - this is a C99 function, causing
1828     some compilers to warn. To avoid this, I renamed it (as "blankclass").
1829    
1830     7. Cosmetic: (a) only output another newline at the end of pcretest if it is
1831     prompting; (b) run "./pcretest /dev/null" at the start of the test script
1832     so the version is shown; (c) stop "make test" echoing "./RunTest".
1833    
1834     8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
1835    
1836     9. The prototype for memmove() for systems that don't have it was using
1837     size_t, but the inclusion of the header that defines size_t was later. I've
1838     moved the #includes for the C headers earlier to avoid this.
1839    
1840     10. Added some adjustments to the code to make it easier to compiler on certain
1841     special systems:
1842    
1843     (a) Some "const" qualifiers were missing.
1844     (b) Added the macro EXPORT before all exported functions; by default this
1845     is defined to be empty.
1846     (c) Changed the dftables auxiliary program (that builds chartables.c) so
1847     that it reads its output file name as an argument instead of writing
1848     to the standard output and assuming this can be redirected.
1849    
1850     11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
1851     class containing characters with values greater than 255, PCRE compilation
1852     went into a loop.
1853    
1854     12. A recursive reference to a subpattern that was within another subpattern
1855     that had a minimum quantifier of zero caused PCRE to crash. For example,
1856     (x(y(?2))z)? provoked this bug with a subject that got as far as the
1857     recursion. If the recursively-called subpattern itself had a zero repeat,
1858     that was OK.
1859    
1860     13. In pcretest, the buffer for reading a data line was set at 30K, but the
1861     buffer into which it was copied (for escape processing) was still set at
1862     1024, so long lines caused crashes.
1863    
1864     14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
1865     "internal error: code overflow...". This applied to any character class
1866     that was followed by a possessive quantifier.
1867    
1868     15. Modified the Makefile to add libpcre.la as a prerequisite for
1869     libpcreposix.la because I was told this is needed for a parallel build to
1870     work.
1871    
1872     16. If a pattern that contained .* following optional items at the start was
1873     studied, the wrong optimizing data was generated, leading to matching
1874     errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
1875     matching string must start with a or b or c. The correct conclusion for
1876     this pattern is that a match can start with any character.
1877    
1878    
1879 nigel 71 Version 4.4 13-Aug-03
1880     ---------------------
1881    
1882     1. In UTF-8 mode, a character class containing characters with values between
1883     127 and 255 was not handled correctly if the compiled pattern was studied.
1884     In fixing this, I have also improved the studying algorithm for such
1885     classes (slightly).
1886    
1887     2. Three internal functions had redundant arguments passed to them. Removal
1888     might give a very teeny performance improvement.
1889    
1890     3. Documentation bug: the value of the capture_top field in a callout is *one
1891     more than* the number of the hightest numbered captured substring.
1892    
1893     4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
1894     in incorrectly linking with a previously installed version. They now link
1895     explicitly with libpcre.la.
1896    
1897     5. configure.in no longer needs to recognize Cygwin specially.
1898    
1899     6. A problem in pcre.in for Windows platforms is fixed.
1900    
1901     7. If a pattern was successfully studied, and the -d (or /D) flag was given to
1902     pcretest, it used to include the size of the study block as part of its
1903     output. Unfortunately, the structure contains a field that has a different
1904     size on different hardware architectures. This meant that the tests that
1905     showed this size failed. As the block is currently always of a fixed size,
1906     this information isn't actually particularly useful in pcretest output, so
1907     I have just removed it.
1908    
1909     8. Three pre-processor statements accidentally did not start in column 1.
1910     Sadly, there are *still* compilers around that complain, even though
1911     standard C has not required this for well over a decade. Sigh.
1912    
1913     9. In pcretest, the code for checking callouts passed small integers in the
1914     callout_data field, which is a void * field. However, some picky compilers
1915     complained about the casts involved for this on 64-bit systems. Now
1916     pcretest passes the address of the small integer instead, which should get
1917     rid of the warnings.
1918    
1919     10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
1920     both compile and run time, and gives an error if an invalid UTF-8 sequence
1921     is found. There is a option for disabling this check in cases where the
1922     string is known to be correct and/or the maximum performance is wanted.
1923    
1924     11. In response to a bug report, I changed one line in Makefile.in from
1925    
1926     -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
1927     to
1928     -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
1929    
1930     to look similar to other lines, but I have no way of telling whether this
1931     is the right thing to do, as I do not use Windows. No doubt I'll get told
1932     if it's wrong...
1933    
1934    
1935 nigel 69 Version 4.3 21-May-03
1936     ---------------------
1937    
1938     1. Two instances of @WIN_PREFIX@ omitted from the Windows targets in the
1939     Makefile.
1940    
1941     2. Some refactoring to improve the quality of the code:
1942    
1943     (i) The utf8_table... variables are now declared "const".
1944    
1945     (ii) The code for \cx, which used the "case flipping" table to upper case
1946     lower case letters, now just substracts 32. This is ASCII-specific,
1947     but the whole concept of \cx is ASCII-specific, so it seems
1948     reasonable.
1949    
1950     (iii) PCRE was using its character types table to recognize decimal and
1951     hexadecimal digits in the pattern. This is silly, because it handles
1952     only 0-9, a-f, and A-F, but the character types table is locale-
1953     specific, which means strange things might happen. A private
1954     table is now used for this - though it costs 256 bytes, a table is
1955     much faster than multiple explicit tests. Of course, the standard
1956     character types table is still used for matching digits in subject
1957     strings against \d.
1958    
1959     (iv) Strictly, the identifier ESC_t is reserved by POSIX (all identifiers
1960     ending in _t are). So I've renamed it as ESC_tee.
1961    
1962     3. The first argument for regexec() in the POSIX wrapper should have been
1963     defined as "const".
1964    
1965     4. Changed pcretest to use malloc() for its buffers so that they can be
1966     Electric Fenced for debugging.
1967    
1968     5. There were several places in the code where, in UTF-8 mode, PCRE would try
1969     to read one or more bytes before the start of the subject string. Often this
1970     had no effect on PCRE's behaviour, but in some circumstances it could
1971     provoke a segmentation fault.
1972    
1973     6. A lookbehind at the start of a pattern in UTF-8 mode could also cause PCRE
1974     to try to read one or more bytes before the start of the subject string.
1975    
1976     7. A lookbehind in a pattern matched in non-UTF-8 mode on a PCRE compiled with
1977     UTF-8 support could misbehave in various ways if the subject string
1978     contained bytes with the 0x80 bit set and the 0x40 bit unset in a lookbehind
1979     area. (PCRE was not checking for the UTF-8 mode flag, and trying to move
1980     back over UTF-8 characters.)
1981    
1982    
1983 nigel 67 Version 4.2 14-Apr-03
1984     ---------------------
1985    
1986     1. Typo "#if SUPPORT_UTF8" instead of "#ifdef SUPPORT_UTF8" fixed.
1987    
1988     2. Changes to the building process, supplied by Ronald Landheer-Cieslak
1989     [ON_WINDOWS]: new variable, "#" on non-Windows platforms
1990     [NOT_ON_WINDOWS]: new variable, "#" on Windows platforms
1991     [WIN_PREFIX]: new variable, "cyg" for Cygwin
1992     * Makefile.in: use autoconf substitution for OBJEXT, EXEEXT, BUILD_OBJEXT
1993     and BUILD_EXEEXT
1994     Note: automatic setting of the BUILD variables is not yet working
1995     set CPPFLAGS and BUILD_CPPFLAGS (but don't use yet) - should be used at
1996     compile-time but not at link-time
1997     [LINK]: use for linking executables only
1998     make different versions for Windows and non-Windows
1999     [LINKLIB]: new variable, copy of UNIX-style LINK, used for linking
2000     libraries
2001     [LINK_FOR_BUILD]: new variable
2002     [OBJEXT]: use throughout
2003     [EXEEXT]: use throughout
2004     <winshared>: new target
2005     <wininstall>: new target
2006     <dftables.o>: use native compiler
2007     <dftables>: use native linker
2008     <install>: handle Windows platform correctly
2009     <clean>: ditto
2010     <check>: ditto
2011     copy DLL to top builddir before testing
2012    
2013     As part of these changes, -no-undefined was removed again. This was reported
2014     to give trouble on HP-UX 11.0, so getting rid of it seems like a good idea
2015     in any case.
2016    
2017     3. Some tidies to get rid of compiler warnings:
2018    
2019     . In the match_data structure, match_limit was an unsigned long int, whereas
2020     match_call_count was an int. I've made them both unsigned long ints.
2021    
2022     . In pcretest the fact that a const uschar * doesn't automatically cast to
2023     a void * provoked a warning.
2024    
2025     . Turning on some more compiler warnings threw up some "shadow" variables
2026     and a few more missing casts.
2027    
2028     4. If PCRE was complied with UTF-8 support, but called without the PCRE_UTF8
2029     option, a class that contained a single character with a value between 128
2030     and 255 (e.g. /[\xFF]/) caused PCRE to crash.
2031    
2032     5. If PCRE was compiled with UTF-8 support, but called without the PCRE_UTF8
2033     option, a class that contained several characters, but with at least one
2034     whose value was between 128 and 255 caused PCRE to crash.
2035    
2036    
2037 nigel 65 Version 4.1 12-Mar-03
2038     ---------------------
2039 nigel 63
2040 nigel 65 1. Compiling with gcc -pedantic found a couple of places where casts were
2041     needed, and a string in dftables.c that was longer than standard compilers are
2042     required to support.
2043    
2044     2. Compiling with Sun's compiler found a few more places where the code could
2045     be tidied up in order to avoid warnings.
2046    
2047     3. The variables for cross-compiling were called HOST_CC and HOST_CFLAGS; the
2048     first of these names is deprecated in the latest Autoconf in favour of the name
2049     CC_FOR_BUILD, because "host" is typically used to mean the system on which the
2050     compiled code will be run. I can't find a reference for HOST_CFLAGS, but by
2051     analogy I have changed it to CFLAGS_FOR_BUILD.
2052    
2053     4. Added -no-undefined to the linking command in the Makefile, because this is
2054     apparently helpful for Windows. To make it work, also added "-L. -lpcre" to the
2055     linking step for the pcreposix library.
2056    
2057     5. PCRE was failing to diagnose the case of two named groups with the same
2058     name.
2059    
2060     6. A problem with one of PCRE's optimizations was discovered. PCRE remembers a
2061     literal character that is needed in the subject for a match, and scans along to
2062     ensure that it is present before embarking on the full matching process. This
2063     saves time in cases of nested unlimited repeats that are never going to match.
2064     Problem: the scan can take a lot of time if the subject is very long (e.g.
2065     megabytes), thus penalizing straightforward matches. It is now done only if the
2066     amount of subject to be scanned is less than 1000 bytes.
2067    
2068     7. A lesser problem with the same optimization is that it was recording the
2069     first character of an anchored pattern as "needed", thus provoking a search
2070     right along the subject, even when the first match of the pattern was going to
2071     fail. The "needed" character is now not set for anchored patterns, unless it
2072     follows something in the pattern that is of non-fixed length. Thus, it still
2073     fulfils its original purpose of finding quick non-matches in cases of nested
2074     unlimited repeats, but isn't used for simple anchored patterns such as /^abc/.
2075    
2076    
2077     Version 4.0 17-Feb-03
2078     ---------------------
2079    
2080 nigel 63 1. If a comment in an extended regex that started immediately after a meta-item
2081     extended to the end of string, PCRE compiled incorrect data. This could lead to
2082     all kinds of weird effects. Example: /#/ was bad; /()#/ was bad; /a#/ was not.
2083    
2084     2. Moved to autoconf 2.53 and libtool 1.4.2.
2085    
2086     3. Perl 5.8 no longer needs "use utf8" for doing UTF-8 things. Consequently,
2087     the special perltest8 script is no longer needed - all the tests can be run
2088     from a single perltest script.
2089    
2090     4. From 5.004, Perl has not included the VT character (0x0b) in the set defined
2091     by \s. It has now been removed in PCRE. This means it isn't recognized as
2092     whitespace in /x regexes too, which is the same as Perl. Note that the POSIX
2093     class [:space:] *does* include VT, thereby creating a mess.
2094    
2095     5. Added the class [:blank:] (a GNU extension from Perl 5.8) to match only
2096     space and tab.
2097    
2098     6. Perl 5.005 was a long time ago. It's time to amalgamate the tests that use
2099     its new features into the main test script, reducing the number of scripts.
2100    
2101     7. Perl 5.8 has changed the meaning of patterns like /a(?i)b/. Earlier versions
2102     were backward compatible, and made the (?i) apply to the whole pattern, as if
2103     /i were given. Now it behaves more logically, and applies the option setting
2104     only to what follows. PCRE has been changed to follow suit. However, if it
2105     finds options settings right at the start of the pattern, it extracts them into
2106     the global options, as before. Thus, they show up in the info data.
2107    
2108     8. Added support for the \Q...\E escape sequence. Characters in between are
2109     treated as literals. This is slightly different from Perl in that $ and @ are
2110     also handled as literals inside the quotes. In Perl, they will cause variable
2111     interpolation. Note the following examples:
2112    
2113     Pattern PCRE matches Perl matches
2114    
2115     \Qabc$xyz\E abc$xyz abc followed by the contents of $xyz
2116     \Qabc\$xyz\E abc\$xyz abc\$xyz
2117     \Qabc\E\$\Qxyz\E abc$xyz abc$xyz
2118    
2119     For compatibility with Perl, \Q...\E sequences are recognized inside character
2120     classes as well as outside them.
2121    
2122     9. Re-organized 3 code statements in pcretest to avoid "overflow in
2123     floating-point constant arithmetic" warnings from a Microsoft compiler. Added a
2124     (size_t) cast to one statement in pcretest and one in pcreposix to avoid
2125     signed/unsigned warnings.
2126    
2127     10. SunOS4 doesn't have strtoul(). This was used only for unpicking the -o
2128     option for pcretest, so I've replaced it by a simple function that does just
2129     that job.
2130    
2131     11. pcregrep was ending with code 0 instead of 2 for the commands "pcregrep" or
2132     "pcregrep -".
2133    
2134     12. Added "possessive quantifiers" ?+, *+, ++, and {,}+ which come from Sun's
2135     Java package. This provides some syntactic sugar for simple cases of what my
2136     documentation calls "once-only subpatterns". A pattern such as x*+ is the same
2137     as (?>x*). In other words, if what is inside (?>...) is just a single repeated
2138     item, you can use this simplified notation. Note that only makes sense with
2139     greedy quantifiers. Consequently, the use of the possessive quantifier forces
2140     greediness, whatever the setting of the PCRE_UNGREEDY option.
2141    
2142     13. A change of greediness default within a pattern was not taking effect at
2143     the current level for patterns like /(b+(?U)a+)/. It did apply to parenthesized
2144     subpatterns that followed. Patterns like /b+(?U)a+/ worked because the option
2145     was abstracted outside.
2146    
2147     14. PCRE now supports the \G assertion. It is true when the current matching
2148     position is at the start point of the match. This differs from \A when the
2149     starting offset is non-zero. Used with the /g option of pcretest (or similar
2150     code), it works in the same way as it does for Perl's /g option. If all
2151     alternatives of a regex begin with \G, the expression is anchored to the start
2152     match position, and the "anchored" flag is set in the compiled expression.
2153    
2154     15. Some bugs concerning the handling of certain option changes within patterns
2155     have been fixed. These applied to options other than (?ims). For example,
2156     "a(?x: b c )d" did not match "XabcdY" but did match "Xa b c dY". It should have
2157     been the other way round. Some of this was related to change 7 above.
2158    
2159     16. PCRE now gives errors for /[.x.]/ and /[=x=]/ as unsupported POSIX
2160     features, as Perl does. Previously, PCRE gave the warnings only for /[[.x.]]/
2161     and /[[=x=]]/. PCRE now also gives an error for /[:name:]/ because it supports
2162     POSIX classes only within a class (e.g. /[[:alpha:]]/).
2163    
2164     17. Added support for Perl's \C escape. This matches one byte, even in UTF8
2165     mode. Unlike ".", it always matches newline, whatever the setting of
2166     PCRE_DOTALL. However, PCRE does not permit \C to appear in lookbehind
2167     assertions. Perl allows it, but it doesn't (in general) work because it can't
2168     calculate the length of the lookbehind. At least, that's the case for Perl
2169     5.8.0 - I've been told they are going to document that it doesn't work in
2170     future.
2171    
2172     18. Added an error diagnosis for escapes that PCRE does not support: these are
2173     \L, \l, \N, \P, \p, \U, \u, and \X.
2174    
2175     19. Although correctly diagnosing a missing ']' in a character class, PCRE was
2176     reading past the end of the pattern in cases such as /[abcd/.
2177    
2178     20. PCRE was getting more memory than necessary for patterns with classes that
2179     contained both POSIX named classes and other characters, e.g. /[[:space:]abc/.
2180    
2181     21. Added some code, conditional on #ifdef VPCOMPAT, to make life easier for
2182     compiling PCRE for use with Virtual Pascal.
2183    
2184     22. Small fix to the Makefile to make it work properly if the build is done
2185     outside the source tree.
2186    
2187     23. Added a new extension: a condition to go with recursion. If a conditional
2188     subpattern starts with (?(R) the "true" branch is used if recursion has
2189     happened, whereas the "false" branch is used only at the top level.
2190    
2191     24. When there was a very long string of literal characters (over 255 bytes
2192     without UTF support, over 250 bytes with UTF support), the computation of how
2193     much memory was required could be incorrect, leading to segfaults or other
2194     strange effects.
2195    
2196     25. PCRE was incorrectly assuming anchoring (either to start of subject or to
2197     start of line for a non-DOTALL pattern) when a pattern started with (.*) and
2198     there was a subsequent back reference to those brackets. This meant that, for
2199     example, /(.*)\d+\1/ failed to match "abc123bc". Unfortunately, it isn't
2200     possible to check for precisely this case. All we can do is abandon the
2201     optimization if .* occurs inside capturing brackets when there are any back
2202     references whatsoever. (See below for a better fix that came later.)
2203    
2204     26. The handling of the optimization for finding the first character of a
2205     non-anchored pattern, and for finding a character that is required later in the
2206     match were failing in some cases. This didn't break the matching; it just
2207     failed to optimize when it could. The way this is done has been re-implemented.
2208    
2209     27. Fixed typo in error message for invalid (?R item (it said "(?p").
2210    
2211     28. Added a new feature that provides some of the functionality that Perl
2212     provides with (?{...}). The facility is termed a "callout". The way it is done
2213     in PCRE is for the caller to provide an optional function, by setting
2214     pcre_callout to its entry point. Like pcre_malloc and pcre_free, this is a
2215     global variable. By default it is unset, which disables all calling out. To get
2216     the function called, the regex must include (?C) at appropriate points. This
2217     is, in fact, equivalent to (?C0), and any number <= 255 may be given with (?C).
2218     This provides a means of identifying different callout points. When PCRE
2219     reaches such a point in the regex, if pcre_callout has been set, the external
2220     function is called. It is provided with data in a structure called
2221     pcre_callout_block, which is defined in pcre.h. If the function returns 0,
2222     matching continues; if it returns a non-zero value, the match at the current
2223     point fails. However, backtracking will occur if possible. [This was changed
2224     later and other features added - see item 49 below.]
2225    
2226     29. pcretest is upgraded to test the callout functionality. It provides a
2227     callout function that displays information. By default, it shows the start of
2228     the match and the current position in the text. There are some new data escapes
2229     to vary what happens:
2230    
2231     \C+ in addition, show current contents of captured substrings
2232     \C- do not supply a callout function
2233     \C!n return 1 when callout number n is reached
2234     \C!n!m return 1 when callout number n is reached for the mth time
2235    
2236     30. If pcregrep was called with the -l option and just a single file name, it
2237     output "<stdin>" if a match was found, instead of the file name.
2238    
2239     31. Improve the efficiency of the POSIX API to PCRE. If the number of capturing
2240     slots is less than POSIX_MALLOC_THRESHOLD, use a block on the stack to pass to
2241     pcre_exec(). This saves a malloc/free per call. The default value of
2242     POSIX_MALLOC_THRESHOLD is 10; it can be changed by --with-posix-malloc-threshold
2243     when configuring.
2244    
2245     32. The default maximum size of a compiled pattern is 64K. There have been a
2246     few cases of people hitting this limit. The code now uses macros to handle the
2247     storing of links as offsets within the compiled pattern. It defaults to 2-byte
2248     links, but this can be changed to 3 or 4 bytes by --with-link-size when
2249     configuring. Tests 2 and 5 work only with 2-byte links because they output
2250     debugging information about compiled patterns.
2251    
2252     33. Internal code re-arrangements:
2253    
2254     (a) Moved the debugging function for printing out a compiled regex into
2255     its own source file (printint.c) and used #include to pull it into
2256     pcretest.c and, when DEBUG is defined, into pcre.c, instead of having two
2257     separate copies.
2258    
2259     (b) Defined the list of op-code names for debugging as a macro in
2260     internal.h so that it is next to the definition of the opcodes.
2261    
2262     (c) Defined a table of op-code lengths for simpler skipping along compiled
2263     code. This is again a macro in internal.h so that it is next to the
2264     definition of the opcodes.
2265    
2266     34. Added support for recursive calls to individual subpatterns, along the
2267     lines of Robin Houston's patch (but implemented somewhat differently).
2268    
2269     35. Further mods to the Makefile to help Win32. Also, added code to pcregrep to
2270     allow it to read and process whole directories in Win32. This code was
2271     contributed by Lionel Fourquaux; it has not been tested by me.
2272    
2273     36. Added support for named subpatterns. The Python syntax (?P<name>...) is
2274     used to name a group. Names consist of alphanumerics and underscores, and must
2275     be unique. Back references use the syntax (?P=name) and recursive calls use
2276     (?P>name) which is a PCRE extension to the Python extension. Groups still have
2277     numbers. The function pcre_fullinfo() can be used after compilation to extract
2278     a name/number map. There are three relevant calls:
2279    
2280     PCRE_INFO_NAMEENTRYSIZE yields the size of each entry in the map
2281     PCRE_INFO_NAMECOUNT yields the number of entries
2282     PCRE_INFO_NAMETABLE yields a pointer to the map.
2283    
2284     The map is a vector of fixed-size entries. The size of each entry depends on
2285     the length of the longest name used. The first two bytes of each entry are the
2286     group number, most significant byte first. There follows the corresponding
2287     name, zero terminated. The names are in alphabetical order.
2288    
2289     37. Make the maximum literal string in the compiled code 250 for the non-UTF-8
2290     case instead of 255. Making it the same both with and without UTF-8 support
2291     means that the same test output works with both.
2292    
2293     38. There was a case of malloc(0) in the POSIX testing code in pcretest. Avoid
2294     calling malloc() with a zero argument.
2295    
2296     39. Change 25 above had to resort to a heavy-handed test for the .* anchoring
2297     optimization. I've improved things by keeping a bitmap of backreferences with
2298     numbers 1-31 so that if .* occurs inside capturing brackets that are not in
2299     fact referenced, the optimization can be applied. It is unlikely that a
2300     relevant occurrence of .* (i.e. one which might indicate anchoring or forcing
2301     the match to follow \n) will appear inside brackets with a number greater than
2302     31, but if it does, any back reference > 31 suppresses the optimization.
2303    
2304     40. Added a new compile-time option PCRE_NO_AUTO_CAPTURE. This has the effect
2305     of disabling numbered capturing parentheses. Any opening parenthesis that is
2306     not followed by ? behaves as if it were followed by ?: but named parentheses
2307     can still be used for capturing (and they will acquire numbers in the usual
2308     way).
2309    
2310     41. Redesigned the return codes from the match() function into yes/no/error so
2311     that errors can be passed back from deep inside the nested calls. A malloc
2312     failure while inside a recursive subpattern call now causes the
2313     PCRE_ERROR_NOMEMORY return instead of quietly going wrong.
2314    
2315     42. It is now possible to set a limit on the number of times the match()
2316     function is called in a call to pcre_exec(). This facility makes it possible to
2317     limit the amount of recursion and backtracking, though not in a directly
2318     obvious way, because the match() function is used in a number of different
2319     circumstances. The count starts from zero for each position in the subject
2320     string (for non-anchored patterns). The default limit is, for compatibility, a
2321     large number, namely 10 000 000. You can change this in two ways:
2322    
2323     (a) When configuring PCRE before making, you can use --with-match-limit=n
2324     to set a default value for the compiled library.
2325    
2326     (b) For each call to pcre_exec(), you can pass a pcre_extra block in which
2327     a different value is set. See 45 below.
2328    
2329     If the limit is exceeded, pcre_exec() returns PCRE_ERROR_MATCHLIMIT.
2330    
2331     43. Added a new function pcre_config(int, void *) to enable run-time extraction
2332     of things that can be changed at compile time. The first argument specifies
2333     what is wanted and the second points to where the information is to be placed.
2334     The current list of available information is:
2335    
2336     PCRE_CONFIG_UTF8
2337    
2338     The output is an integer that is set to one if UTF-8 support is available;
2339     otherwise it is set to zero.
2340    
2341     PCRE_CONFIG_NEWLINE
2342    
2343     The output is an integer that it set to the value of the code that is used for
2344     newline. It is either LF (10) or CR (13).
2345    
2346     PCRE_CONFIG_LINK_SIZE
2347    
2348     The output is an integer that contains the number of bytes used for internal
2349     linkage in compiled expressions. The value is 2, 3, or 4. See item 32 above.
2350    
2351     PCRE_CONFIG_POSIX_MALLOC_THRESHOLD
2352    
2353     The output is an integer that contains the threshold above which the POSIX
2354     interface uses malloc() for output vectors. See item 31 above.
2355    
2356     PCRE_CONFIG_MATCH_LIMIT
2357    
2358     The output is an unsigned integer that contains the default limit of the number
2359     of match() calls in a pcre_exec() execution. See 42 above.
2360    
2361     44. pcretest has been upgraded by the addition of the -C option. This causes it
2362     to extract all the available output from the new pcre_config() function, and to
2363     output it. The program then exits immediately.
2364    
2365     45. A need has arisen to pass over additional data with calls to pcre_exec() in
2366     order to support additional features. One way would have been to define
2367     pcre_exec2() (for example) with extra arguments, but this would not have been
2368     extensible, and would also have required all calls to the original function to
2369     be mapped to the new one. Instead, I have chosen to extend the mechanism that
2370     is used for passing in "extra" data from pcre_study().
2371    
2372     The pcre_extra structure is now exposed and defined in pcre.h. It currently
2373     contains the following fields:
2374    
2375     flags a bitmap indicating which of the following fields are set
2376     study_data opaque data from pcre_study()
2377     match_limit a way of specifying a limit on match() calls for a specific
2378     call to pcre_exec()
2379     callout_data data for callouts (see 49 below)
2380    
2381     The flag bits are also defined in pcre.h, and are
2382    
2383     PCRE_EXTRA_STUDY_DATA
2384     PCRE_EXTRA_MATCH_LIMIT
2385     PCRE_EXTRA_CALLOUT_DATA
2386    
2387     The pcre_study() function now returns one of these new pcre_extra blocks, with
2388     the actual study data pointed to by the study_data field, and the
2389     PCRE_EXTRA_STUDY_DATA flag set. This can be passed directly to pcre_exec() as
2390     before. That is, this change is entirely upwards-compatible and requires no
2391     change to existing code.
2392    
2393     If you want to pass in additional data to pcre_exec(), you can either place it
2394     in a pcre_extra block provided by pcre_study(), or create your own pcre_extra
2395     block.
2396    
2397     46. pcretest has been extended to test the PCRE_EXTRA_MATCH_LIMIT feature. If a
2398     data string contains the escape sequence \M, pcretest calls pcre_exec() several
2399     times with different match limits, until it finds the minimum value needed for
2400     pcre_exec() to complete. The value is then output. This can be instructive; for
2401     most simple matches the number is quite small, but for pathological cases it
2402     gets very large very quickly.
2403    
2404     47. There's a new option for pcre_fullinfo() called PCRE_INFO_STUDYSIZE. It
2405     returns the size of the data block pointed to by the study_data field in a
2406     pcre_extra block, that is, the value that was passed as the argument to
2407     pcre_malloc() when PCRE was getting memory in which to place the information
2408     created by pcre_study(). The fourth argument should point to a size_t variable.
2409     pcretest has been extended so that this information is shown after a successful
2410     pcre_study() call when information about the compiled regex is being displayed.
2411    
2412     48. Cosmetic change to Makefile: there's no need to have / after $(DESTDIR)
2413     because what follows is always an absolute path. (Later: it turns out that this
2414     is more than cosmetic for MinGW, because it doesn't like empty path
2415     components.)
2416    
2417     49. Some changes have been made to the callout feature (see 28 above):
2418    
2419     (i) A callout function now has three choices for what it returns:
2420    
2421     0 => success, carry on matching
2422     > 0 => failure at this point, but backtrack if possible
2423     < 0 => serious error, return this value from pcre_exec()
2424    
2425     Negative values should normally be chosen from the set of PCRE_ERROR_xxx
2426     values. In particular, returning PCRE_ERROR_NOMATCH forces a standard
2427     "match failed" error. The error number PCRE_ERROR_CALLOUT is reserved for
2428     use by callout functions. It will never be used by PCRE itself.
2429    
2430     (ii) The pcre_extra structure (see 45 above) has a void * field called
2431     callout_data, with corresponding flag bit PCRE_EXTRA_CALLOUT_DATA. The
2432     pcre_callout_block structure has a field of the same name. The contents of
2433     the field passed in the pcre_extra structure are passed to the callout
2434     function in the corresponding field in the callout block. This makes it
2435     easier to use the same callout-containing regex from multiple threads. For
2436     testing, the pcretest program has a new data escape
2437    
2438     \C*n pass the number n (may be negative) as callout_data
2439    
2440     If the callout function in pcretest receives a non-zero value as
2441     callout_data, it returns that value.
2442    
2443     50. Makefile wasn't handling CFLAGS properly when compiling dftables. Also,
2444     there were some redundant $(CFLAGS) in commands that are now specified as
2445     $(LINK), which already includes $(CFLAGS).
2446    
2447     51. Extensions to UTF-8 support are listed below. These all apply when (a) PCRE
2448     has been compiled with UTF-8 support *and* pcre_compile() has been compiled
2449     with the PCRE_UTF8 flag. Patterns that are compiled without that flag assume
2450     one-byte characters throughout. Note that case-insensitive matching applies
2451     only to characters whose values are less than 256. PCRE doesn't support the
2452     notion of cases for higher-valued characters.
2453    
2454     (i) A character class whose characters are all within 0-255 is handled as
2455     a bit map, and the map is inverted for negative classes. Previously, a
2456     character > 255 always failed to match such a class; however it should
2457     match if the class was a negative one (e.g. [^ab]). This has been fixed.
2458    
2459     (ii) A negated character class with a single character < 255 is coded as
2460     "not this character" (OP_NOT). This wasn't working properly when the test
2461     character was multibyte, either singly or repeated.
2462    
2463     (iii) Repeats of multibyte characters are now handled correctly in UTF-8
2464     mode, for example: \x{100}{2,3}.
2465    
2466     (iv) The character escapes \b, \B, \d, \D, \s, \S, \w, and \W (either
2467     singly or repeated) now correctly test multibyte characters. However,
2468     PCRE doesn't recognize any characters with values greater than 255 as
2469     digits, spaces, or word characters. Such characters always match \D, \S,
2470     and \W, and never match \d, \s, or \w.
2471    
2472     (v) Classes may now contain characters and character ranges with values
2473     greater than 255. For example: [ab\x{100}-\x{400}].
2474    
2475     (vi) pcregrep now has a --utf-8 option (synonym -u) which makes it call
2476     PCRE in UTF-8 mode.
2477    
2478     52. The info request value PCRE_INFO_FIRSTCHAR has been renamed
2479     PCRE_INFO_FIRSTBYTE because it is a byte value. However, the old name is
2480     retained for backwards compatibility. (Note that LASTLITERAL is also a byte
2481     value.)
2482    
2483     53. The single man page has become too large. I have therefore split it up into
2484     a number of separate man pages. These also give rise to individual HTML pages;
2485     these are now put in a separate directory, and there is an index.html page that
2486     lists them all. Some hyperlinking between the pages has been installed.
2487    
2488     54. Added convenience functions for handling named capturing parentheses.
2489    
2490     55. Unknown escapes inside character classes (e.g. [\M]) and escapes that
2491     aren't interpreted therein (e.g. [\C]) are literals in Perl. This is now also
2492     true in PCRE, except when the PCRE_EXTENDED option is set, in which case they
2493     are faulted.
2494    
2495     56. Introduced HOST_CC and HOST_CFLAGS which can be set in the environment when
2496     calling configure. These values are used when compiling the dftables.c program
2497     which is run to generate the source of the default character tables. They
2498     default to the values of CC and CFLAGS. If you are cross-compiling PCRE,
2499     you will need to set these values.
2500    
2501     57. Updated the building process for Windows DLL, as provided by Fred Cox.
2502    
2503    
2504     Version 3.9 02-Jan-02
2505 nigel 61 ---------------------
2506    
2507     1. A bit of extraneous text had somehow crept into the pcregrep documentation.
2508    
2509     2. If --disable-static was given, the building process failed when trying to
2510     build pcretest and pcregrep. (For some reason it was using libtool to compile
2511     them, which is not right, as they aren't part of the library.)
2512    
2513    
2514 nigel 59 Version 3.8 18-Dec-01
2515     ---------------------
2516    
2517     1. The experimental UTF-8 code was completely screwed up. It was packing the
2518     bytes in the wrong order. How dumb can you get?
2519    
2520    
2521 nigel 57 Version 3.7 29-Oct-01
2522     ---------------------
2523    
2524     1. In updating pcretest to check change 1 of version 3.6, I screwed up.
2525     This caused pcretest, when used on the test data, to segfault. Unfortunately,
2526     this didn't happen under Solaris 8, where I normally test things.
2527    
2528 nigel 59 2. The Makefile had to be changed to make it work on BSD systems, where 'make'
2529     doesn't seem to recognize that ./xxx and xxx are the same file. (This entry
2530     isn't in ChangeLog distributed with 3.7 because I forgot when I hastily made
2531     this fix an hour or so after the initial 3.7 release.)
2532 nigel 57
2533 nigel 59
2534 nigel 55 Version 3.6 23-Oct-01
2535     ---------------------
2536    
2537     1. Crashed with /(sens|respons)e and \1ibility/ and "sense and sensibility" if
2538     offsets passed as NULL with zero offset count.
2539    
2540     2. The config.guess and config.sub files had not been updated when I moved to
2541     the latest autoconf.
2542    
2543    
2544 nigel 53 Version 3.5 15-Aug-01
2545     ---------------------
2546 nigel 5
2547 nigel 53 1. Added some missing #if !defined NOPOSIX conditionals in pcretest.c that
2548     had been forgotten.
2549    
2550     2. By using declared but undefined structures, we can avoid using "void"
2551     definitions in pcre.h while keeping the internal definitions of the structures
2552     private.
2553    
2554     3. The distribution is now built using autoconf 2.50 and libtool 1.4. From a
2555     user point of view, this means that both static and shared libraries are built
2556     by default, but this can be individually controlled. More of the work of
2557     handling this static/shared cases is now inside libtool instead of PCRE's make
2558     file.
2559    
2560     4. The pcretest utility is now installed along with pcregrep because it is
2561     useful for users (to test regexs) and by doing this, it automatically gets
2562     relinked by libtool. The documentation has been turned into a man page, so
2563     there are now .1, .txt, and .html versions in /doc.
2564    
2565     5. Upgrades to pcregrep:
2566     (i) Added long-form option names like gnu grep.
2567     (ii) Added --help to list all options with an explanatory phrase.
2568     (iii) Added -r, --recursive to recurse into sub-directories.
2569     (iv) Added -f, --file to read patterns from a file.
2570    
2571     6. pcre_exec() was referring to its "code" argument before testing that
2572     argument for NULL (and giving an error if it was NULL).
2573    
2574     7. Upgraded Makefile.in to allow for compiling in a different directory from
2575     the source directory.
2576    
2577     8. Tiny buglet in pcretest: when pcre_fullinfo() was called to retrieve the
2578     options bits, the pointer it was passed was to an int instead of to an unsigned
2579     long int. This mattered only on 64-bit systems.
2580    
2581     9. Fixed typo (3.4/1) in pcre.h again. Sigh. I had changed pcre.h (which is
2582     generated) instead of pcre.in, which it its source. Also made the same change
2583     in several of the .c files.
2584    
2585     10. A new release of gcc defines printf() as a macro, which broke pcretest
2586     because it had an ifdef in the middle of a string argument for printf(). Fixed
2587     by using separate calls to printf().
2588    
2589     11. Added --enable-newline-is-cr and --enable-newline-is-lf to the configure
2590     script, to force use of CR or LF instead of \n in the source. On non-Unix
2591     systems, the value can be set in config.h.
2592    
2593     12. The limit of 200 on non-capturing parentheses is a _nesting_ limit, not an
2594     absolute limit. Changed the text of the error message to make this clear, and
2595     likewise updated the man page.
2596    
2597     13. The limit of 99 on the number of capturing subpatterns has been removed.
2598     The new limit is 65535, which I hope will not be a "real" limit.
2599    
2600    
2601 nigel 51 Version 3.4 22-Aug-00
2602     ---------------------
2603    
2604     1. Fixed typo in pcre.h: unsigned const char * changed to const unsigned char *.
2605    
2606     2. Diagnose condition (?(0) as an error instead of crashing on matching.
2607    
2608    
2609 nigel 49 Version 3.3 01-Aug-00
2610     ---------------------
2611    
2612     1. If an octal character was given, but the value was greater than \377, it
2613     was not getting masked to the least significant bits, as documented. This could
2614     lead to crashes in some systems.
2615    
2616     2. Perl 5.6 (if not earlier versions) accepts classes like [a-\d] and treats
2617     the hyphen as a literal. PCRE used to give an error; it now behaves like Perl.
2618    
2619     3. Added the functions pcre_free_substring() and pcre_free_substring_list().
2620     These just pass their arguments on to (pcre_free)(), but they are provided
2621     because some uses of PCRE bind it to non-C systems that can call its functions,
2622     but cannot call free() or pcre_free() directly.
2623    
2624     4. Add "make test" as a synonym for "make check". Corrected some comments in
2625     the Makefile.
2626    
2627     5. Add $(DESTDIR)/ in front of all the paths in the "install" target in the
2628     Makefile.
2629    
2630     6. Changed the name of pgrep to pcregrep, because Solaris has introduced a
2631     command called pgrep for grepping around the active processes.
2632    
2633     7. Added the beginnings of support for UTF-8 character strings.
2634    
2635     8. Arranged for the Makefile to pass over the settings of CC, CFLAGS, and
2636     RANLIB to ./ltconfig so that they are used by libtool. I think these are all
2637     the relevant ones. (AR is not passed because ./ltconfig does its own figuring
2638     out for the ar command.)
2639    
2640    
2641 nigel 47 Version 3.2 12-May-00
2642     ---------------------
2643    
2644     This is purely a bug fixing release.
2645    
2646     1. If the pattern /((Z)+|A)*/ was matched agained ZABCDEFG it matched Z instead
2647     of ZA. This was just one example of several cases that could provoke this bug,
2648     which was introduced by change 9 of version 2.00. The code for breaking
2649     infinite loops after an iteration that matches an empty string was't working
2650     correctly.
2651    
2652     2. The pcretest program was not imitating Perl correctly for the pattern /a*/g
2653     when matched against abbab (for example). After matching an empty string, it
2654     wasn't forcing anchoring when setting PCRE_NOTEMPTY for the next attempt; this
2655     caused it to match further down the string than it should.
2656    
2657     3. The code contained an inclusion of sys/types.h. It isn't clear why this
2658     was there because it doesn't seem to be needed, and it causes trouble on some
2659     systems, as it is not a Standard C header. It has been removed.
2660    
2661     4. Made 4 silly changes to the source to avoid stupid compiler warnings that
2662     were reported on the Macintosh. The changes were from
2663    
2664     while ((c = *(++ptr)) != 0 && c != '\n');
2665     to
2666     while ((c = *(++ptr)) != 0 && c != '\n') ;
2667    
2668     Totally extraordinary, but if that's what it takes...
2669    
2670     5. PCRE is being used in one environment where neither memmove() nor bcopy() is
2671     available. Added HAVE_BCOPY and an autoconf test for it; if neither
2672     HAVE_MEMMOVE nor HAVE_BCOPY is set, use a built-in emulation function which
2673     assumes the way PCRE uses memmove() (always moving upwards).
2674    
2675     6. PCRE is being used in one environment where strchr() is not available. There
2676     was only one use in pcre.c, and writing it out to avoid strchr() probably gives
2677     faster code anyway.
2678    
2679    
2680 nigel 45 Version 3.1 09-Feb-00
2681     ---------------------
2682    
2683     The only change in this release is the fixing of some bugs in Makefile.in for
2684     the "install" target:
2685    
2686     (1) It was failing to install pcreposix.h.
2687    
2688     (2) It was overwriting the pcre.3 man page with the pcreposix.3 man page.
2689    
2690    
2691 nigel 43 Version 3.0 01-Feb-00
2692     ---------------------
2693 nigel 41
2694     1. Add support for the /+ modifier to perltest (to output $` like it does in
2695     pcretest).
2696    
2697     2. Add support for the /g modifier to perltest.
2698    
2699     3. Fix pcretest so that it behaves even more like Perl for /g when the pattern
2700     matches null strings.
2701    
2702     4. Fix perltest so that it doesn't do unwanted things when fed an empty
2703     pattern. Perl treats empty patterns specially - it reuses the most recent
2704     pattern, which is not what we want. Replace // by /(?#)/ in order to avoid this
2705     effect.
2706    
2707     5. The POSIX interface was broken in that it was just handing over the POSIX
2708     captured string vector to pcre_exec(), but (since release 2.00) PCRE has
2709     required a bigger vector, with some working space on the end. This means that
2710     the POSIX wrapper now has to get and free some memory, and copy the results.
2711    
2712 nigel 43 6. Added some simple autoconf support, placing the test data and the
2713     documentation in separate directories, re-organizing some of the
2714     information files, and making it build pcre-config (a GNU standard). Also added
2715     libtool support for building PCRE as a shared library, which is now the
2716     default.
2717 nigel 41
2718 nigel 43 7. Got rid of the leading zero in the definition of PCRE_MINOR because 08 and
2719     09 are not valid octal constants. Single digits will be used for minor values
2720     less than 10.
2721    
2722     8. Defined REG_EXTENDED and REG_NOSUB as zero in the POSIX header, so that
2723     existing programs that set these in the POSIX interface can use PCRE without
2724     modification.
2725    
2726     9. Added a new function, pcre_fullinfo() with an extensible interface. It can
2727     return all that pcre_info() returns, plus additional data. The pcre_info()
2728     function is retained for compatibility, but is considered to be obsolete.
2729    
2730     10. Added experimental recursion feature (?R) to handle one common case that
2731     Perl 5.6 will be able to do with (?p{...}).
2732    
2733     11. Added support for POSIX character classes like [:alpha:], which Perl is
2734     adopting.
2735    
2736    
2737 nigel 39 Version 2.08 31-Aug-99
2738     ----------------------
2739    
2740     1. When startoffset was not zero and the pattern began with ".*", PCRE was not
2741     trying to match at the startoffset position, but instead was moving forward to
2742     the next newline as if a previous match had failed.
2743    
2744     2. pcretest was not making use of PCRE_NOTEMPTY when repeating for /g and /G,
2745     and could get into a loop if a null string was matched other than at the start
2746     of the subject.
2747    
2748     3. Added definitions of PCRE_MAJOR and PCRE_MINOR to pcre.h so the version can
2749     be distinguished at compile time, and for completeness also added PCRE_DATE.
2750    
2751     5. Added Paul Sokolovsky's minor changes to make it easy to compile a Win32 DLL
2752     in GnuWin32 environments.
2753    
2754    
2755 nigel 37 Version 2.07 29-Jul-99
2756     ----------------------
2757    
2758     1. The documentation is now supplied in plain text form and HTML as well as in
2759     the form of man page sources.
2760    
2761     2. C++ compilers don't like assigning (void *) values to other pointer types.
2762     In particular this affects malloc(). Although there is no problem in Standard
2763     C, I've put in casts to keep C++ compilers happy.
2764    
2765     3. Typo on pcretest.c; a cast of (unsigned char *) in the POSIX regexec() call
2766     should be (const char *).
2767    
2768     4. If NOPOSIX is defined, pcretest.c compiles without POSIX support. This may
2769     be useful for non-Unix systems who don't want to bother with the POSIX stuff.
2770     However, I haven't made this a standard facility. The documentation doesn't
2771     mention it, and the Makefile doesn't support it.
2772    
2773     5. The Makefile now contains an "install" target, with editable destinations at
2774     the top of the file. The pcretest program is not installed.
2775    
2776     6. pgrep -V now gives the PCRE version number and date.
2777    
2778     7. Fixed bug: a zero repetition after a literal string (e.g. /abcde{0}/) was
2779     causing the entire string to be ignored, instead of just the last character.
2780    
2781     8. If a pattern like /"([^\\"]+|\\.)*"/ is applied in the normal way to a
2782     non-matching string, it can take a very, very long time, even for strings of
2783     quite modest length, because of the nested recursion. PCRE now does better in
2784     some of these cases. It does this by remembering the last required literal
2785     character in the pattern, and pre-searching the subject to ensure it is present
2786     before running the real match. In other words, it applies a heuristic to detect
2787     some types of certain failure quickly, and in the above example, if presented
2788     with a string that has no trailing " it gives "no match" very quickly.
2789    
2790     9. A new runtime option PCRE_NOTEMPTY causes null string matches to be ignored;
2791     other alternatives are tried instead.
2792    
2793    
2794 nigel 35 Version 2.06 09-Jun-99
2795     ----------------------
2796    
2797     1. Change pcretest's output for amount of store used to show just the code
2798     space, because the remainder (the data block) varies in size between 32-bit and
2799     64-bit systems.
2800    
2801     2. Added an extra argument to pcre_exec() to supply an offset in the subject to
2802     start matching at. This allows lookbehinds to work when searching for multiple
2803     occurrences in a string.
2804    
2805     3. Added additional options to pcretest for testing multiple occurrences:
2806    
2807     /+ outputs the rest of the string that follows a match
2808     /g loops for multiple occurrences, using the new startoffset argument
2809     /G loops for multiple occurrences by passing an incremented pointer
2810    
2811     4. PCRE wasn't doing the "first character" optimization for patterns starting
2812     with \b or \B, though it was doing it for other lookbehind assertions. That is,
2813     it wasn't noticing that a match for a pattern such as /\bxyz/ has to start with
2814     the letter 'x'. On long subject strings, this gives a significant speed-up.
2815    
2816    
2817 nigel 33 Version 2.05 21-Apr-99
2818     ----------------------
2819    
2820     1. Changed the type of magic_number from int to long int so that it works
2821     properly on 16-bit systems.
2822    
2823     2. Fixed a bug which caused patterns starting with .* not to work correctly
2824     when the subject string contained newline characters. PCRE was assuming
2825     anchoring for such patterns in all cases, which is not correct because .* will
2826     not pass a newline unless PCRE_DOTALL is set. It now assumes anchoring only if
2827     DOTALL is set at top level; otherwise it knows that patterns starting with .*
2828     must be retried after every newline in the subject.
2829    
2830    
2831 nigel 31 Version 2.04 18-Feb-99
2832     ----------------------
2833    
2834     1. For parenthesized subpatterns with repeats whose minimum was zero, the
2835     computation of the store needed to hold the pattern was incorrect (too large).
2836     If such patterns were nested a few deep, this could multiply and become a real
2837     problem.
2838    
2839     2. Added /M option to pcretest to show the memory requirement of a specific
2840     pattern. Made -m a synonym of -s (which does this globally) for compatibility.
2841    
2842     3. Subpatterns of the form (regex){n,m} (i.e. limited maximum) were being
2843     compiled in such a way that the backtracking after subsequent failure was
2844     pessimal. Something like (a){0,3} was compiled as (a)?(a)?(a)? instead of
2845     ((a)((a)(a)?)?)? with disastrous performance if the maximum was of any size.
2846    
2847    
2848 nigel 29 Version 2.03 02-Feb-99
2849     ----------------------
2850    
2851     1. Fixed typo and small mistake in man page.
2852    
2853 nigel 31 2. Added 4th condition (GPL supersedes if conflict) and created separate
2854     LICENCE file containing the conditions.
2855 nigel 29
2856     3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
2857     Perl, that is the internal \ allows the delimiter to be included in the
2858     pattern. Locked out the use of \ as a delimiter. If \ immediately follows
2859     the final delimiter, add \ to the end of the pattern (to test the error).
2860    
2861     4. Added the convenience functions for extracting substrings after a successful
2862     match. Updated pcretest to make it able to test these functions.
2863    
2864    
2865 nigel 27 Version 2.02 14-Jan-99
2866     ----------------------
2867    
2868     1. Initialized the working variables associated with each extraction so that
2869     their saving and restoring doesn't refer to uninitialized store.
2870    
2871     2. Put dummy code into study.c in order to trick the optimizer of the IBM C
2872     compiler for OS/2 into generating correct code. Apparently IBM isn't going to
2873     fix the problem.
2874    
2875     3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
2876     calls, and wasn't printing the correct value for compiling calls. Increased the
2877     default value of LOOPREPEAT, and the number of significant figures in the
2878     times.
2879    
2880     4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
2881    
2882     5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
2883     a building problem on Windows NT with a FAT file system.
2884    
2885    
2886 nigel 25 Version 2.01 21-Oct-98
2887     ----------------------
2888    
2889     1. Changed the API for pcre_compile() to allow for the provision of a pointer
2890     to character tables built by pcre_maketables() in the current locale. If NULL
2891     is passed, the default tables are used.
2892    
2893    
2894 nigel 23 Version 2.00 24-Sep-98
2895 nigel 21 ----------------------
2896    
2897 nigel 23 1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
2898     it any more.
2899    
2900     2. Allow quantification of (?>) groups, and make it work correctly.
2901    
2902     3. The first character computation wasn't working for (?>) groups.
2903    
2904     4. Correct the implementation of \Z (it is permitted to match on the \n at the
2905     end of the subject) and add 5.005's \z, which really does match only at the
2906     very end of the subject.
2907    
2908     5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
2909    
2910     6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
2911     DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
2912     localized options. All options to pcre_study() were also removed.
2913    
2914     7. Add other new features from 5.005:
2915    
2916     $(?<= positive lookbehind
2917     $(?<! negative lookbehind
2918     (?imsx-imsx) added the unsetting capability
2919     such a setting is global if at outer level; local otherwise
2920     (?imsx-imsx:) non-capturing groups with option setting
2921     (?(cond)re|re) conditional pattern matching
2922    
2923     A backreference to itself in a repeated group matches the previous
2924     captured string.
2925    
2926     8. General tidying up of studying (both automatic and via "study")
2927     consequential on the addition of new assertions.
2928    
2929     9. As in 5.005, unlimited repeated groups that could match an empty substring
2930     are no longer faulted at compile time. Instead, the loop is forcibly broken at
2931     runtime if any iteration does actually match an empty substring.
2932    
2933     10. Include the RunTest script in the distribution.
2934    
2935     11. Added tests from the Perl 5.005_02 distribution. This showed up a few
2936     discrepancies, some of which were old and were also with respect to 5.004. They
2937     have now been fixed.
2938    
2939    
2940     Version 1.09 28-Apr-98
2941     ----------------------
2942    
2943 nigel 21 1. A negated single character class followed by a quantifier with a minimum
2944     value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
2945     program crashes, or just wrong answers. This did not apply to negated classes
2946     containing more than one character, or to minima other than one.
2947    
2948    
2949 nigel 19 Version 1.08 27-Mar-98
2950     ----------------------
2951    
2952     1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
2953    
2954     2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
2955     latter must appear before anything that relies on it in the pattern.
2956    
2957    
2958 nigel 17 Version 1.07 16-Feb-98
2959     ----------------------
2960    
2961     1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
2962     repeat of a potentially empty string).
2963    
2964    
2965 nigel 15 Version 1.06 23-Jan-98
2966     ----------------------
2967    
2968     1. Added Markus Oberhumer's little patches for C++.
2969    
2970     2. Literal strings longer than 255 characters were broken.
2971    
2972    
2973 nigel 13 Version 1.05 23-Dec-97
2974     ----------------------
2975    
2976     1. Negated character classes containing more than one character were failing if
2977     PCRE_CASELESS was set at run time.
2978    
2979    
2980 nigel 11 Version 1.04 19-Dec-97
2981     ----------------------
2982    
2983     1. Corrected the man page, where some "const" qualifiers had been omitted.
2984    
2985     2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
2986     input syntax.
2987    
2988     3. Fixed memory leak which occurred when a regex with back references was
2989     matched with an offsets vector that wasn't big enough. The temporary memory
2990     that is used in this case wasn't being freed if the match failed.
2991    
2992     4. Tidied pcretest to ensure it frees memory that it gets.
2993    
2994     5. Temporary memory was being obtained in the case where the passed offsets
2995     vector was exactly big enough.
2996    
2997     6. Corrected definition of offsetof() from change 5 below.
2998    
2999     7. I had screwed up change 6 below and broken the rules for the use of
3000     setjmp(). Now fixed.
3001    
3002    
3003 nigel 9 Version 1.03 18-Dec-97
3004     ----------------------
3005    
3006     1. A erroneous regex with a missing opening parenthesis was correctly
3007     diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
3008     on some systems.
3009    
3010     2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
3011     it was reported that one broken compiler failed on the former because "code" is
3012     also an independent variable.
3013    
3014     3. The erroneous regex a[]b caused an array overrun reference.
3015    
3016     4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
3017     fail on data ending with that character. (It was going on too far, and checking
3018     the next character, typically a binary zero.) This was specific to the
3019     optimized code for single-character negative classes.
3020    
3021     5. Added a contributed patch from the TIN world which does the following:
3022    
3023     + Add an undef for memmove, in case the the system defines a macro for it.
3024    
3025     + Add a definition of offsetof(), in case there isn't one. (I don't know
3026     the reason behind this - offsetof() is part of the ANSI standard - but
3027     it does no harm).
3028    
3029     + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
3030     most of the places where whitespace preceded '#'. I have given up and
3031     allowed the remaining 2 cases to be at the margin.
3032    
3033     + Rename some variables in pcre to eliminate shadowing. This seems very
3034     pedantic, but does no harm, of course.
3035    
3036     6. Moved the call to setjmp() into its own function, to get rid of warnings
3037     from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
3038    
3039     7. Constructs such as \d{8,} were compiling into the equivalent of
3040 nigel 11 \d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
3041 nigel 9 outcome, but in this particular case used more store than had been allocated,
3042     which caused the bug to be discovered because it threw up an internal error.
3043    
3044     8. The debugging code in both pcre and pcretest for outputting the compiled
3045     form of a regex was going wrong in the case of back references followed by
3046     curly-bracketed repeats.
3047    
3048    
3049 nigel 7 Version 1.02 12-Dec-97
3050     ----------------------
3051    
3052     1. Typos in pcre.3 and comments in the source fixed.
3053    
3054     2. Applied a contributed patch to get rid of places where it used to remove
3055     'const' from variables, and fixed some signed/unsigned and uninitialized
3056     variable warnings.
3057    
3058     3. Added the "runtest" target to Makefile.
3059    
3060     4. Set default compiler flag to -O2 rather than just -O.
3061    
3062    
3063 nigel 5 Version 1.01 19-Nov-97
3064     ----------------------
3065    
3066     1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
3067     like /([ab]*)*/, that is, for classes with more than one character in them.
3068    
3069     2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
3070     as /((?>a*))*/ (a PCRE_EXTRA facility).
3071    
3072    
3073     Version 1.00 18-Nov-97
3074     ----------------------
3075    
3076     1. Added compile-time macros to support systems such as SunOS4 which don't have
3077     memmove() or strerror() but have other things that can be used instead.
3078    
3079     2. Arranged that "make clean" removes the executables.
3080    
3081    
3082 nigel 3 Version 0.99 27-Oct-97
3083     ----------------------
3084    
3085     1. Fixed bug in code for optimizing classes with only one character. It was
3086     initializing a 32-byte map regardless, which could cause it to run off the end
3087     of the memory it had got.
3088    
3089     2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
3090    
3091    
3092     Version 0.98 22-Oct-97
3093     ----------------------
3094    
3095     1. Fixed bug in code for handling temporary memory usage when there are more
3096     back references than supplied space in the ovector. This could cause segfaults.
3097    
3098    
3099     Version 0.97 21-Oct-97
3100     ----------------------
3101    
3102     1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
3103    
3104     2. Optimized negated single characters not to use a bit map.
3105    
3106     3. Brought error texts together as macro definitions; clarified some of them;
3107     fixed one that was wrong - it said "range out of order" when it meant "invalid
3108     escape sequence".
3109    
3110     4. Changed some char * arguments to const char *.
3111    
3112     5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
3113    
3114     6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
3115     pcretest.
3116    
3117    
3118     Version 0.96 16-Oct-97
3119     ----------------------
3120    
3121     1. Added a simple "pgrep" utility to the distribution.
3122    
3123     2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
3124     unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
3125     where "ddd" means "one or more decimal digits".
3126    
3127     3. Fixed serious bug. If a pattern had a back reference, but the call to
3128     pcre_exec() didn't supply a large enough ovector to record the related
3129     identifying subpattern, the match always failed. PCRE now remembers the number
3130     of the largest back reference, and gets some temporary memory in which to save
3131     the offsets during matching if necessary, in order to ensure that
3132     backreferences always work.
3133    
3134     4. Increased the compatibility with Perl in a number of ways:
3135    
3136     (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
3137     to request this handling. The option can be set at compile or exec time.
3138    
3139     (b) $ matches before a terminating newline by default; an option
3140     PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
3141     mode). The option can be set at compile or exec time.
3142    
3143     (c) The handling of \ followed by a digit other than 0 is now supposed to be
3144     the same as Perl's. If the decimal number it represents is less than 10
3145     or there aren't that many previous left capturing parentheses, an octal
3146     escape is read. Inside a character class, it's always an octal escape,
3147     even if it is a single digit.
3148    
3149     (d) An escaped but undefined alphabetic character is taken as a literal,
3150     unless PCRE_EXTRA is set. Currently this just reserves the remaining
3151     escapes.
3152    
3153     (e) {0} is now permitted. (The previous item is removed from the compiled
3154     pattern).
3155    
3156     5. Changed all the names of code files so that the basic parts are no longer
3157     than 10 characters, and abolished the teeny "globals.c" file.
3158    
3159     6. Changed the handling of character classes; they are now done with a 32-byte
3160     bit map always.
3161    
3162     7. Added the -d and /D options to pcretest to make it possible to look at the
3163     internals of compilation without having to recompile pcre.
3164    
3165    
3166     Version 0.95 23-Sep-97
3167     ----------------------
3168    
3169     1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
3170     \x20 at the start of a run of normal characters. These were being treated as
3171     real characters, instead of the source characters being re-checked.
3172    
3173    
3174     Version 0.94 18-Sep-97
3175     ----------------------
3176    
3177     1. The functions are now thread-safe, with the caveat that the global variables
3178     containing pointers to malloc() and free() or alternative functions are the
3179     same for all threads.
3180    
3181     2. Get pcre_study() to generate a bitmap of initial characters for non-
3182     anchored patterns when this is possible, and use it if passed to pcre_exec().
3183    
3184    
3185     Version 0.93 15-Sep-97
3186     ----------------------
3187    
3188     1. /(b)|(:+)/ was computing an incorrect first character.
3189    
3190     2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
3191     but not actually doing anything yet.
3192    
3193     3. Treat "-" characters in classes that cannot be part of ranges as literals,
3194     as Perl does (e.g. [-az] or [az-]).
3195    
3196     4. Set the anchored flag if a branch starts with .* or .*? because that tests
3197     all possible positions.
3198    
3199     5. Split up into different modules to avoid including unneeded functions in a
3200     compiled binary. However, compile and exec are still in one module. The "study"
3201     function is split off.
3202    
3203     6. The character tables are now in a separate module whose source is generated
3204     by an auxiliary program - but can then be edited by hand if required. There are
3205     now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
3206     toupper() in the code.
3207    
3208     7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
3209     make them global. Abolish the function for setting them, as the caller can now
3210     set them directly.
3211    
3212    
3213     Version 0.92 11-Sep-97
3214     ----------------------
3215    
3216     1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
3217     (e.g. /a{1,3}/) was broken (I mis-optimized it).
3218    
3219     2. Caseless matching was not working in character classes if the characters in
3220     the pattern were in upper case.
3221    
3222     3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
3223    
3224     4. Make PCRE_ANCHORED public and accept as a compile option.
3225    
3226     5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
3227     PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
3228     pass them.
3229    
3230     6. Give an error if bad option bits passed at compile or run time.
3231    
3232     7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
3233     pcretest to cause it to pass that flag.
3234    
3235     8. Add pcre_info(), to get the number of identifying subpatterns, the stored
3236     options, and the first character, if set.
3237    
3238     9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
3239    
3240    
3241     Version 0.91 10-Sep-97
3242     ----------------------
3243    
3244     1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
3245     match the empty string as in /(a*)*/. It was looping and ultimately crashing.
3246    
3247     2. PCRE was looping on encountering an indefinitely repeated back reference to
3248     a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
3249     Perl does - treats the match as successful.
3250    
3251     ****

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