ViewVC logotype

Diff of /code/trunk/ChangeLog

Parent Directory Parent Directory | Revision Log Revision Log | View Patch Patch

revision 69 by nigel, Sat Feb 24 21:40:18 2007 UTC revision 75 by nigel, Sat Feb 24 21:40:37 2007 UTC
# Line 1  Line 1 
1  ChangeLog for PCRE  ChangeLog for PCRE
2  ------------------  ------------------
4    Version 5.0 13-Sep-04
5    ---------------------
7     1. Internal change: literal characters are no longer packed up into items
8        containing multiple characters in a single byte-string. Each character
9        is now matched using a separate opcode. However, there may be more than one
10        byte in the character in UTF-8 mode.
12     2. The pcre_callout_block structure has two new fields: pattern_position and
13        next_item_length. These contain the offset in the pattern to the next match
14        item, and its length, respectively.
16     3. The PCRE_AUTO_CALLOUT option for pcre_compile() requests the automatic
17        insertion of callouts before each pattern item. Added the /C option to
18        pcretest to make use of this.
20     4. On the advice of a Windows user, the lines
22          #if defined(_WIN32) || defined(WIN32)
23          _setmode( _fileno( stdout ), 0x8000 );
24          #endif  /* defined(_WIN32) || defined(WIN32) */
26        have been added to the source of pcretest. This apparently does useful
27        magic in relation to line terminators.
29     5. Changed "r" and "w" in the calls to fopen() in pcretest to "rb" and "wb"
30        for the benefit of those environments where the "b" makes a difference.
32     6. The icc compiler has the same options as gcc, but "configure" doesn't seem
33        to know about it. I have put a hack into configure.in that adds in code
34        to set GCC=yes if CC=icc. This seems to end up at a point in the
35        generated configure script that is early enough to affect the setting of
36        compiler options, which is what is needed, but I have no means of testing
37        whether it really works. (The user who reported this had patched the
38        generated configure script, which of course I cannot do.)
40        LATER: After change 22 below (new libtool files), the configure script
41        seems to know about icc (and also ecc). Therefore, I have commented out
42        this hack in configure.in.
44     7. Added support for pkg-config (2 patches were sent in).
46     8. Negated POSIX character classes that used a combination of internal tables
47        were completely broken. These were [[:^alpha:]], [[:^alnum:]], and
48        [[:^ascii]]. Typically, they would match almost any characters. The other
49        POSIX classes were not broken in this way.
51     9. Matching the pattern "\b.*?" against "ab cd", starting at offset 1, failed
52        to find the match, as PCRE was deluded into thinking that the match had to
53        start at the start point or following a newline. The same bug applied to
54        patterns with negative forward assertions or any backward assertions
55        preceding ".*" at the start, unless the pattern required a fixed first
56        character. This was a failing pattern: "(?!.bcd).*". The bug is now fixed.
58    10. In UTF-8 mode, when moving forwards in the subject after a failed match
59        starting at the last subject character, bytes beyond the end of the subject
60        string were read.
62    11. Renamed the variable "class" as "classbits" to make life easier for C++
63        users. (Previously there was a macro definition, but it apparently wasn't
64        enough.)
66    12. Added the new field "tables" to the extra data so that tables can be passed
67        in at exec time, or the internal tables can be re-selected. This allows
68        a compiled regex to be saved and re-used at a later time by a different
69        program that might have everything at different addresses.
71    13. Modified the pcre-config script so that, when run on Solaris, it shows a
72        -R library as well as a -L library.
74    14. The debugging options of pcretest (-d on the command line or D on a
75        pattern) showed incorrect output for anything following an extended class
76        that contained multibyte characters and which was followed by a quantifier.
78    15. Added optional support for general category Unicode character properties
79        via the \p, \P, and \X escapes. Unicode property support implies UTF-8
80        support. It adds about 90K to the size of the library. The meanings of the
81        inbuilt class escapes such as \d and \s have NOT been changed.
83    16. Updated pcredemo.c to include calls to free() to release the memory for the
84        compiled pattern.
86    17. The generated file chartables.c was being created in the source directory
87        instead of in the building directory. This caused the build to fail if the
88        source directory was different from the building directory, and was
89        read-only.
91    18. Added some sample Win commands from Mark Tetrode into the NON-UNIX-USE
92        file. No doubt somebody will tell me if they don't make sense... Also added
93        Dan Mooney's comments about building on OpenVMS.
95    19. Added support for partial matching via the PCRE_PARTIAL option for
96        pcre_exec() and the \P data escape in pcretest.
98    20. Extended pcretest with 3 new pattern features:
100        (i)   A pattern option of the form ">rest-of-line" causes pcretest to
101              write the compiled pattern to the file whose name is "rest-of-line".
102              This is a straight binary dump of the data, with the saved pointer to
103              the character tables forced to be NULL. The study data, if any, is
104              written too. After writing, pcretest reads a new pattern.
106        (ii)  If, instead of a pattern, "<rest-of-line" is given, pcretest reads a
107              compiled pattern from the given file. There must not be any
108              occurrences of "<" in the file name (pretty unlikely); if there are,
109              pcretest will instead treat the initial "<" as a pattern delimiter.
110              After reading in the pattern, pcretest goes on to read data lines as
111              usual.
113        (iii) The F pattern option causes pcretest to flip the bytes in the 32-bit
114              and 16-bit fields in a compiled pattern, to simulate a pattern that
115              was compiled on a host of opposite endianness.
117    21. The pcre-exec() function can now cope with patterns that were compiled on
118        hosts of opposite endianness, with this restriction:
120          As for any compiled expression that is saved and used later, the tables
121          pointer field cannot be preserved; the extra_data field in the arguments
122          to pcre_exec() should be used to pass in a tables address if a value
123          other than the default internal tables were used at compile time.
125    22. Calling pcre_exec() with a negative value of the "ovecsize" parameter is
126        now diagnosed as an error. Previously, most of the time, a negative number
127        would have been treated as zero, but if in addition "ovector" was passed as
128        NULL, a crash could occur.
130    23. Updated the files ltmain.sh, config.sub, config.guess, and aclocal.m4 with
131        new versions from the libtool 1.5 distribution (the last one is a copy of
132        a file called libtool.m4). This seems to have fixed the need to patch
133        "configure" to support Darwin 1.3 (which I used to do). However, I still
134        had to patch ltmain.sh to ensure that ${SED} is set (it isn't on my
135        workstation).
137    24. Changed the PCRE licence to be the more standard "BSD" licence.
140    Version 4.5 01-Dec-03
141    ---------------------
143     1. There has been some re-arrangement of the code for the match() function so
144        that it can be compiled in a version that does not call itself recursively.
145        Instead, it keeps those local variables that need separate instances for
146        each "recursion" in a frame on the heap, and gets/frees frames whenever it
147        needs to "recurse". Keeping track of where control must go is done by means
148        of setjmp/longjmp. The whole thing is implemented by a set of macros that
149        hide most of the details from the main code, and operates only if
150        NO_RECURSE is defined while compiling pcre.c. If PCRE is built using the
151        "configure" mechanism, "--disable-stack-for-recursion" turns on this way of
152        operating.
154        To make it easier for callers to provide specially tailored get/free
155        functions for this usage, two new functions, pcre_stack_malloc, and
156        pcre_stack_free, are used. They are always called in strict stacking order,
157        and the size of block requested is always the same.
159        The PCRE_CONFIG_STACKRECURSE info parameter can be used to find out whether
160        PCRE has been compiled to use the stack or the heap for recursion. The
161        -C option of pcretest uses this to show which version is compiled.
163        A new data escape \S, is added to pcretest; it causes the amounts of store
164        obtained and freed by both kinds of malloc/free at match time to be added
165        to the output.
167     2. Changed the locale test to use "fr_FR" instead of "fr" because that's
168        what's available on my current Linux desktop machine.
170     3. When matching a UTF-8 string, the test for a valid string at the start has
171        been extended. If start_offset is not zero, PCRE now checks that it points
172        to a byte that is the start of a UTF-8 character. If not, it returns
173        PCRE_ERROR_BADUTF8_OFFSET (-11). Note: the whole string is still checked;
174        this is necessary because there may be backward assertions in the pattern.
175        When matching the same subject several times, it may save resources to use
176        PCRE_NO_UTF8_CHECK on all but the first call if the string is long.
178     4. The code for checking the validity of UTF-8 strings has been tightened so
179        that it rejects (a) strings containing 0xfe or 0xff bytes and (b) strings
180        containing "overlong sequences".
182     5. Fixed a bug (appearing twice) that I could not find any way of exploiting!
183        I had written "if ((digitab[*p++] && chtab_digit) == 0)" where the "&&"
184        should have been "&", but it just so happened that all the cases this let
185        through by mistake were picked up later in the function.
187     6. I had used a variable called "isblank" - this is a C99 function, causing
188        some compilers to warn. To avoid this, I renamed it (as "blankclass").
190     7. Cosmetic: (a) only output another newline at the end of pcretest if it is
191        prompting; (b) run "./pcretest /dev/null" at the start of the test script
192        so the version is shown; (c) stop "make test" echoing "./RunTest".
194     8. Added patches from David Burgess to enable PCRE to run on EBCDIC systems.
196     9. The prototype for memmove() for systems that don't have it was using
197        size_t, but the inclusion of the header that defines size_t was later. I've
198        moved the #includes for the C headers earlier to avoid this.
200    10. Added some adjustments to the code to make it easier to compiler on certain
201        special systems:
203          (a) Some "const" qualifiers were missing.
204          (b) Added the macro EXPORT before all exported functions; by default this
205              is defined to be empty.
206          (c) Changed the dftables auxiliary program (that builds chartables.c) so
207              that it reads its output file name as an argument instead of writing
208              to the standard output and assuming this can be redirected.
210    11. In UTF-8 mode, if a recursive reference (e.g. (?1)) followed a character
211        class containing characters with values greater than 255, PCRE compilation
212        went into a loop.
214    12. A recursive reference to a subpattern that was within another subpattern
215        that had a minimum quantifier of zero caused PCRE to crash. For example,
216        (x(y(?2))z)? provoked this bug with a subject that got as far as the
217        recursion. If the recursively-called subpattern itself had a zero repeat,
218        that was OK.
220    13. In pcretest, the buffer for reading a data line was set at 30K, but the
221        buffer into which it was copied (for escape processing) was still set at
222        1024, so long lines caused crashes.
224    14. A pattern such as /[ab]{1,3}+/ failed to compile, giving the error
225        "internal error: code overflow...". This applied to any character class
226        that was followed by a possessive quantifier.
228    15. Modified the Makefile to add libpcre.la as a prerequisite for
229        libpcreposix.la because I was told this is needed for a parallel build to
230        work.
232    16. If a pattern that contained .* following optional items at the start was
233        studied, the wrong optimizing data was generated, leading to matching
234        errors. For example, studying /[ab]*.*c/ concluded, erroneously, that any
235        matching string must start with a or b or c. The correct conclusion for
236        this pattern is that a match can start with any character.
239    Version 4.4 13-Aug-03
240    ---------------------
242     1. In UTF-8 mode, a character class containing characters with values between
243        127 and 255 was not handled correctly if the compiled pattern was studied.
244        In fixing this, I have also improved the studying algorithm for such
245        classes (slightly).
247     2. Three internal functions had redundant arguments passed to them. Removal
248        might give a very teeny performance improvement.
250     3. Documentation bug: the value of the capture_top field in a callout is *one
251        more than* the number of the hightest numbered captured substring.
253     4. The Makefile linked pcretest and pcregrep with -lpcre, which could result
254        in incorrectly linking with a previously installed version. They now link
255        explicitly with libpcre.la.
257     5. configure.in no longer needs to recognize Cygwin specially.
259     6. A problem in pcre.in for Windows platforms is fixed.
261     7. If a pattern was successfully studied, and the -d (or /D) flag was given to
262        pcretest, it used to include the size of the study block as part of its
263        output. Unfortunately, the structure contains a field that has a different
264        size on different hardware architectures. This meant that the tests that
265        showed this size failed. As the block is currently always of a fixed size,
266        this information isn't actually particularly useful in pcretest output, so
267        I have just removed it.
269     8. Three pre-processor statements accidentally did not start in column 1.
270        Sadly, there are *still* compilers around that complain, even though
271        standard C has not required this for well over a decade. Sigh.
273     9. In pcretest, the code for checking callouts passed small integers in the
274        callout_data field, which is a void * field. However, some picky compilers
275        complained about the casts involved for this on 64-bit systems. Now
276        pcretest passes the address of the small integer instead, which should get
277        rid of the warnings.
279    10. By default, when in UTF-8 mode, PCRE now checks for valid UTF-8 strings at
280        both compile and run time, and gives an error if an invalid UTF-8 sequence
281        is found. There is a option for disabling this check in cases where the
282        string is known to be correct and/or the maximum performance is wanted.
284    11. In response to a bug report, I changed one line in Makefile.in from
286            -Wl,--out-implib,.libs/lib@WIN_PREFIX@pcreposix.dll.a \
287        to
288            -Wl,--out-implib,.libs/@WIN_PREFIX@libpcreposix.dll.a \
290        to look similar to other lines, but I have no way of telling whether this
291        is the right thing to do, as I do not use Windows. No doubt I'll get told
292        if it's wrong...
295  Version 4.3 21-May-03  Version 4.3 21-May-03
296  ---------------------  ---------------------

Removed from v.69  
changed lines
  Added in v.75

  ViewVC Help
Powered by ViewVC 1.1.5