Contents of /code/trunk/ChangeLog

ChangeLog for PCRE
------------------


Version 2.03 02-Feb-99
----------------------

1. Fixed typo and small mistake in man page.

2. Added 4th condition (GPL supersedes) and created separate LICENCE file.

3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
Perl, that is the internal \ allows the delimiter to be included in the
pattern. Locked out the use of \ as a delimiter. If \ immediately follows
the final delimiter, add \ to the end of the pattern (to test the error).

4. Added the convenience functions for extracting substrings after a successful
match. Updated pcretest to make it able to test these functions.


Version 2.02 14-Jan-99
----------------------

1. Initialized the working variables associated with each extraction so that
their saving and restoring doesn't refer to uninitialized store.

2. Put dummy code into study.c in order to trick the optimizer of the IBM C
compiler for OS/2 into generating correct code. Apparently IBM isn't going to
fix the problem.

3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
calls, and wasn't printing the correct value for compiling calls. Increased the
default value of LOOPREPEAT, and the number of significant figures in the
times.

4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.

5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
a building problem on Windows NT with a FAT file system.


Version 2.01 21-Oct-98
----------------------

1. Changed the API for pcre_compile() to allow for the provision of a pointer
to character tables built by pcre_maketables() in the current locale. If NULL
is passed, the default tables are used.


Version 2.00 24-Sep-98
----------------------

1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
it any more.

2. Allow quantification of (?>) groups, and make it work correctly.

3. The first character computation wasn't working for (?>) groups.

4. Correct the implementation of \Z (it is permitted to match on the \n at the
end of the subject) and add 5.005's \z, which really does match only at the
very end of the subject.

5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.

6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
localized options. All options to pcre_study() were also removed.

7. Add other new features from 5.005:

   $(?<=           positive lookbehind
   $(?<!           negative lookbehind
   (?imsx-imsx)    added the unsetting capability
                   such a setting is global if at outer level; local otherwise
   (?imsx-imsx:)   non-capturing groups with option setting
   (?(cond)re|re)  conditional pattern matching

   A backreference to itself in a repeated group matches the previous
   captured string.

8. General tidying up of studying (both automatic and via "study")
consequential on the addition of new assertions.

9. As in 5.005, unlimited repeated groups that could match an empty substring
are no longer faulted at compile time. Instead, the loop is forcibly broken at
runtime if any iteration does actually match an empty substring.

10. Include the RunTest script in the distribution.

11. Added tests from the Perl 5.005_02 distribution. This showed up a few
discrepancies, some of which were old and were also with respect to 5.004. They
have now been fixed.


Version 1.09 28-Apr-98
----------------------

1. A negated single character class followed by a quantifier with a minimum
value of one (e.g.  [^x]{1,6}  ) was not compiled correctly. This could lead to
program crashes, or just wrong answers. This did not apply to negated classes
containing more than one character, or to minima other than one.


Version 1.08 27-Mar-98
----------------------

1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.

2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
latter must appear before anything that relies on it in the pattern.


Version 1.07 16-Feb-98
----------------------

1. A pattern such as /((a)*)*/ was not being diagnosed as in error (unlimited
repeat of a potentially empty string).


Version 1.06 23-Jan-98
----------------------

1. Added Markus Oberhumer's little patches for C++.

2. Literal strings longer than 255 characters were broken.


Version 1.05 23-Dec-97
----------------------

1. Negated character classes containing more than one character were failing if
PCRE_CASELESS was set at run time.


Version 1.04 19-Dec-97
----------------------

1. Corrected the man page, where some "const" qualifiers had been omitted.

2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
input syntax.

3. Fixed memory leak which occurred when a regex with back references was
matched with an offsets vector that wasn't big enough. The temporary memory
that is used in this case wasn't being freed if the match failed.

4. Tidied pcretest to ensure it frees memory that it gets.

5. Temporary memory was being obtained in the case where the passed offsets
vector was exactly big enough.

6. Corrected definition of offsetof() from change 5 below.

7. I had screwed up change 6 below and broken the rules for the use of
setjmp(). Now fixed.


Version 1.03 18-Dec-97
----------------------

1. A erroneous regex with a missing opening parenthesis was correctly
diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
on some systems.

2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
it was reported that one broken compiler failed on the former because "code" is
also an independent variable.

3. The erroneous regex a[]b caused an array overrun reference.

4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
fail on data ending with that character. (It was going on too far, and checking
the next character, typically a binary zero.) This was specific to the
optimized code for single-character negative classes.

5. Added a contributed patch from the TIN world which does the following:

  + Add an undef for memmove, in case the the system defines a macro for it.

  + Add a definition of offsetof(), in case there isn't one. (I don't know
    the reason behind this - offsetof() is part of the ANSI standard - but
    it does no harm).

  + Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
    most of the places where whitespace preceded '#'. I have given up and
    allowed the remaining 2 cases to be at the margin.

  + Rename some variables in pcre to eliminate shadowing. This seems very
    pedantic, but does no harm, of course.

6. Moved the call to setjmp() into its own function, to get rid of warnings
from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.

7. Constructs such as \d{8,} were compiling into the equivalent of
\d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
outcome, but in this particular case used more store than had been allocated,
which caused the bug to be discovered because it threw up an internal error.

8. The debugging code in both pcre and pcretest for outputting the compiled
form of a regex was going wrong in the case of back references followed by
curly-bracketed repeats.


Version 1.02 12-Dec-97
----------------------

1. Typos in pcre.3 and comments in the source fixed.

2. Applied a contributed patch to get rid of places where it used to remove
'const' from variables, and fixed some signed/unsigned and uninitialized
variable warnings.

3. Added the "runtest" target to Makefile.

4. Set default compiler flag to -O2 rather than just -O.


Version 1.01 19-Nov-97
----------------------

1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
like /([ab]*)*/, that is, for classes with more than one character in them.

2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
as /((?>a*))*/ (a PCRE_EXTRA facility).


Version 1.00 18-Nov-97
----------------------

1. Added compile-time macros to support systems such as SunOS4 which don't have
memmove() or strerror() but have other things that can be used instead.

2. Arranged that "make clean" removes the executables.


Version 0.99 27-Oct-97
----------------------

1. Fixed bug in code for optimizing classes with only one character. It was
initializing a 32-byte map regardless, which could cause it to run off the end
of the memory it had got.

2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.


Version 0.98 22-Oct-97
----------------------

1. Fixed bug in code for handling temporary memory usage when there are more
back references than supplied space in the ovector. This could cause segfaults.


Version 0.97 21-Oct-97
----------------------

1. Added the \X "cut" facility, conditional on PCRE_EXTRA.

2. Optimized negated single characters not to use a bit map.

3. Brought error texts together as macro definitions; clarified some of them;
fixed one that was wrong - it said "range out of order" when it meant "invalid
escape sequence".

4. Changed some char * arguments to const char *.

5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).

6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
pcretest.


Version 0.96 16-Oct-97
----------------------

1. Added a simple "pgrep" utility to the distribution.

2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
where "ddd" means "one or more decimal digits".

3. Fixed serious bug. If a pattern had a back reference, but the call to
pcre_exec() didn't supply a large enough ovector to record the related
identifying subpattern, the match always failed. PCRE now remembers the number
of the largest back reference, and gets some temporary memory in which to save
the offsets during matching if necessary, in order to ensure that
backreferences always work.

4. Increased the compatibility with Perl in a number of ways:

  (a) . no longer matches \n by default; an option PCRE_DOTALL is provided
      to request this handling. The option can be set at compile or exec time.

  (b) $ matches before a terminating newline by default; an option
      PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
      mode). The option can be set at compile or exec time.

  (c) The handling of \ followed by a digit other than 0 is now supposed to be
      the same as Perl's. If the decimal number it represents is less than 10
      or there aren't that many previous left capturing parentheses, an octal
      escape is read. Inside a character class, it's always an octal escape,
      even if it is a single digit.

  (d) An escaped but undefined alphabetic character is taken as a literal,
      unless PCRE_EXTRA is set. Currently this just reserves the remaining
      escapes.

  (e) {0} is now permitted. (The previous item is removed from the compiled
      pattern).

5. Changed all the names of code files so that the basic parts are no longer
than 10 characters, and abolished the teeny "globals.c" file.

6. Changed the handling of character classes; they are now done with a 32-byte
bit map always.

7. Added the -d and /D options to pcretest to make it possible to look at the
internals of compilation without having to recompile pcre.


Version 0.95 23-Sep-97
----------------------

1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
\x20 at the start of a run of normal characters. These were being treated as
real characters, instead of the source characters being re-checked.


Version 0.94 18-Sep-97
----------------------

1. The functions are now thread-safe, with the caveat that the global variables
containing pointers to malloc() and free() or alternative functions are the
same for all threads.

2. Get pcre_study() to generate a bitmap of initial characters for non-
anchored patterns when this is possible, and use it if passed to pcre_exec().


Version 0.93 15-Sep-97
----------------------

1. /(b)|(:+)/ was computing an incorrect first character.

2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
but not actually doing anything yet.

3. Treat "-" characters in classes that cannot be part of ranges as literals,
as Perl does (e.g. [-az] or [az-]).

4. Set the anchored flag if a branch starts with .* or .*? because that tests
all possible positions.

5. Split up into different modules to avoid including unneeded functions in a
compiled binary. However, compile and exec are still in one module. The "study"
function is split off.

6. The character tables are now in a separate module whose source is generated
by an auxiliary program - but can then be edited by hand if required. There are
now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
toupper() in the code.

7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
make them global. Abolish the function for setting them, as the caller can now
set them directly.


Version 0.92 11-Sep-97
----------------------

1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
(e.g. /a{1,3}/) was broken (I mis-optimized it).

2. Caseless matching was not working in character classes if the characters in
the pattern were in upper case.

3. Make ranges like [W-c] work in the same way as Perl for caseless matching.

4. Make PCRE_ANCHORED public and accept as a compile option.

5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
pass them.

6. Give an error if bad option bits passed at compile or run time.

7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
pcretest to cause it to pass that flag.

8. Add pcre_info(), to get the number of identifying subpatterns, the stored
options, and the first character, if set.

9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.


Version 0.91 10-Sep-97
----------------------

1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
match the empty string as in /(a*)*/. It was looping and ultimately crashing.

2. PCRE was looping on encountering an indefinitely repeated back reference to
a subpattern that had matched an empty string, e.g. /(a|)\1*/. It now does what
Perl does - treats the match as successful.

****
1	nigel	3	ChangeLog for PCRE
2			------------------
3
4	nigel	5
5	nigel	29	Version 2.03 02-Feb-99
6			----------------------
7
8			1. Fixed typo and small mistake in man page.
9
10			2. Added 4th condition (GPL supersedes) and created separate LICENCE file.
11
12			3. Updated pcretest so that patterns such as /abc\/def/ work like they do in
13			Perl, that is the internal \ allows the delimiter to be included in the
14			pattern. Locked out the use of \ as a delimiter. If \ immediately follows
15			the final delimiter, add \ to the end of the pattern (to test the error).
16
17			4. Added the convenience functions for extracting substrings after a successful
18			match. Updated pcretest to make it able to test these functions.
19
20
21	nigel	27	Version 2.02 14-Jan-99
22			----------------------
23
24			1. Initialized the working variables associated with each extraction so that
25			their saving and restoring doesn't refer to uninitialized store.
26
27			2. Put dummy code into study.c in order to trick the optimizer of the IBM C
28			compiler for OS/2 into generating correct code. Apparently IBM isn't going to
29			fix the problem.
30
31			3. Pcretest: the timing code wasn't using LOOPREPEAT for timing execution
32			calls, and wasn't printing the correct value for compiling calls. Increased the
33			default value of LOOPREPEAT, and the number of significant figures in the
34			times.
35
36			4. Changed "/bin/rm" in the Makefile to "-rm" so it works on Windows NT.
37
38			5. Renamed "deftables" as "dftables" to get it down to 8 characters, to avoid
39			a building problem on Windows NT with a FAT file system.
40
41
42	nigel	25	Version 2.01 21-Oct-98
43			----------------------
44
45			1. Changed the API for pcre_compile() to allow for the provision of a pointer
46			to character tables built by pcre_maketables() in the current locale. If NULL
47			is passed, the default tables are used.
48
49
50	nigel	23	Version 2.00 24-Sep-98
51	nigel	21	----------------------
52
53	nigel	23	1. Since the (>?) facility is in Perl 5.005, don't require PCRE_EXTRA to enable
54			it any more.
55
56			2. Allow quantification of (?>) groups, and make it work correctly.
57
58			3. The first character computation wasn't working for (?>) groups.
59
60			4. Correct the implementation of \Z (it is permitted to match on the \n at the
61			end of the subject) and add 5.005's \z, which really does match only at the
62			very end of the subject.
63
64			5. Remove the \X "cut" facility; Perl doesn't have it, and (?> is neater.
65
66			6. Remove the ability to specify CASELESS, MULTILINE, DOTALL, and
67			DOLLAR_END_ONLY at runtime, to make it possible to implement the Perl 5.005
68			localized options. All options to pcre_study() were also removed.
69
70			7. Add other new features from 5.005:
71
72			$(?<= positive lookbehind
73			$(?<! negative lookbehind
74			(?imsx-imsx) added the unsetting capability
75			such a setting is global if at outer level; local otherwise
76			(?imsx-imsx:) non-capturing groups with option setting
77			(?(cond)re\|re) conditional pattern matching
78
79			A backreference to itself in a repeated group matches the previous
80			captured string.
81
82			8. General tidying up of studying (both automatic and via "study")
83			consequential on the addition of new assertions.
84
85			9. As in 5.005, unlimited repeated groups that could match an empty substring
86			are no longer faulted at compile time. Instead, the loop is forcibly broken at
87			runtime if any iteration does actually match an empty substring.
88
89			10. Include the RunTest script in the distribution.
90
91			11. Added tests from the Perl 5.005_02 distribution. This showed up a few
92			discrepancies, some of which were old and were also with respect to 5.004. They
93			have now been fixed.
94
95
96			Version 1.09 28-Apr-98
97			----------------------
98
99	nigel	21	1. A negated single character class followed by a quantifier with a minimum
100			value of one (e.g. [^x]{1,6} ) was not compiled correctly. This could lead to
101			program crashes, or just wrong answers. This did not apply to negated classes
102			containing more than one character, or to minima other than one.
103
104
105	nigel	19	Version 1.08 27-Mar-98
106			----------------------
107
108			1. Add PCRE_UNGREEDY to invert the greediness of quantifiers.
109
110			2. Add (?U) and (?X) to set PCRE_UNGREEDY and PCRE_EXTRA respectively. The
111			latter must appear before anything that relies on it in the pattern.
112
113
114	nigel	17	Version 1.07 16-Feb-98
115			----------------------
116
117			1. A pattern such as /((a))/ was not being diagnosed as in error (unlimited
118			repeat of a potentially empty string).
119
120
121	nigel	15	Version 1.06 23-Jan-98
122			----------------------
123
124			1. Added Markus Oberhumer's little patches for C++.
125
126			2. Literal strings longer than 255 characters were broken.
127
128
129	nigel	13	Version 1.05 23-Dec-97
130			----------------------
131
132			1. Negated character classes containing more than one character were failing if
133			PCRE_CASELESS was set at run time.
134
135
136	nigel	11	Version 1.04 19-Dec-97
137			----------------------
138
139			1. Corrected the man page, where some "const" qualifiers had been omitted.
140
141			2. Made debugging output print "{0,xxx}" instead of just "{,xxx}" to agree with
142			input syntax.
143
144			3. Fixed memory leak which occurred when a regex with back references was
145			matched with an offsets vector that wasn't big enough. The temporary memory
146			that is used in this case wasn't being freed if the match failed.
147
148			4. Tidied pcretest to ensure it frees memory that it gets.
149
150			5. Temporary memory was being obtained in the case where the passed offsets
151			vector was exactly big enough.
152
153			6. Corrected definition of offsetof() from change 5 below.
154
155			7. I had screwed up change 6 below and broken the rules for the use of
156			setjmp(). Now fixed.
157
158
159	nigel	9	Version 1.03 18-Dec-97
160			----------------------
161
162			1. A erroneous regex with a missing opening parenthesis was correctly
163			diagnosed, but PCRE attempted to access brastack[-1], which could cause crashes
164			on some systems.
165
166			2. Replaced offsetof(real_pcre, code) by offsetof(real_pcre, code[0]) because
167			it was reported that one broken compiler failed on the former because "code" is
168			also an independent variable.
169
170			3. The erroneous regex a[]b caused an array overrun reference.
171
172			4. A regex ending with a one-character negative class (e.g. /[^k]$/) did not
173			fail on data ending with that character. (It was going on too far, and checking
174			the next character, typically a binary zero.) This was specific to the
175			optimized code for single-character negative classes.
176
177			5. Added a contributed patch from the TIN world which does the following:
178
179			+ Add an undef for memmove, in case the the system defines a macro for it.
180
181			+ Add a definition of offsetof(), in case there isn't one. (I don't know
182			the reason behind this - offsetof() is part of the ANSI standard - but
183			it does no harm).
184
185			+ Reduce the ifdef's in pcre.c using macro DPRINTF, thereby eliminating
186			most of the places where whitespace preceded '#'. I have given up and
187			allowed the remaining 2 cases to be at the margin.
188
189			+ Rename some variables in pcre to eliminate shadowing. This seems very
190			pedantic, but does no harm, of course.
191
192			6. Moved the call to setjmp() into its own function, to get rid of warnings
193			from gcc -Wall, and avoided calling it at all unless PCRE_EXTRA is used.
194
195			7. Constructs such as \d{8,} were compiling into the equivalent of
196	nigel	11	\d{8}\d{0,65527} instead of \d{8}\d* which didn't make much difference to the
197	nigel	9	outcome, but in this particular case used more store than had been allocated,
198			which caused the bug to be discovered because it threw up an internal error.
199
200			8. The debugging code in both pcre and pcretest for outputting the compiled
201			form of a regex was going wrong in the case of back references followed by
202			curly-bracketed repeats.
203
204
205	nigel	7	Version 1.02 12-Dec-97
206			----------------------
207
208			1. Typos in pcre.3 and comments in the source fixed.
209
210			2. Applied a contributed patch to get rid of places where it used to remove
211			'const' from variables, and fixed some signed/unsigned and uninitialized
212			variable warnings.
213
214			3. Added the "runtest" target to Makefile.
215
216			4. Set default compiler flag to -O2 rather than just -O.
217
218
219	nigel	5	Version 1.01 19-Nov-97
220			----------------------
221
222			1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
223			like /([ab])/, that is, for classes with more than one character in them.
224
225			2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
226			as /((?>a))/ (a PCRE_EXTRA facility).
227
228
229			Version 1.00 18-Nov-97
230			----------------------
231
232			1. Added compile-time macros to support systems such as SunOS4 which don't have
233			memmove() or strerror() but have other things that can be used instead.
234
235			2. Arranged that "make clean" removes the executables.
236
237
238	nigel	3	Version 0.99 27-Oct-97
239			----------------------
240
241			1. Fixed bug in code for optimizing classes with only one character. It was
242			initializing a 32-byte map regardless, which could cause it to run off the end
243			of the memory it had got.
244
245			2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
246
247
248			Version 0.98 22-Oct-97
249			----------------------
250
251			1. Fixed bug in code for handling temporary memory usage when there are more
252			back references than supplied space in the ovector. This could cause segfaults.
253
254
255			Version 0.97 21-Oct-97
256			----------------------
257
258			1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
259
260			2. Optimized negated single characters not to use a bit map.
261
262			3. Brought error texts together as macro definitions; clarified some of them;
263			fixed one that was wrong - it said "range out of order" when it meant "invalid
264			escape sequence".
265
266			4. Changed some char * arguments to const char *.
267
268			5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
269
270			6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
271			pcretest.
272
273
274			Version 0.96 16-Oct-97
275			----------------------
276
277			1. Added a simple "pgrep" utility to the distribution.
278
279			2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
280			unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
281			where "ddd" means "one or more decimal digits".
282
283			3. Fixed serious bug. If a pattern had a back reference, but the call to
284			pcre_exec() didn't supply a large enough ovector to record the related
285			identifying subpattern, the match always failed. PCRE now remembers the number
286			of the largest back reference, and gets some temporary memory in which to save
287			the offsets during matching if necessary, in order to ensure that
288			backreferences always work.
289
290			4. Increased the compatibility with Perl in a number of ways:
291
292			(a) . no longer matches \n by default; an option PCRE_DOTALL is provided
293			to request this handling. The option can be set at compile or exec time.
294
295			(b) $ matches before a terminating newline by default; an option
296			PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
297			mode). The option can be set at compile or exec time.
298
299			(c) The handling of \ followed by a digit other than 0 is now supposed to be
300			the same as Perl's. If the decimal number it represents is less than 10
301			or there aren't that many previous left capturing parentheses, an octal
302			escape is read. Inside a character class, it's always an octal escape,
303			even if it is a single digit.
304
305			(d) An escaped but undefined alphabetic character is taken as a literal,
306			unless PCRE_EXTRA is set. Currently this just reserves the remaining
307			escapes.
308
309			(e) {0} is now permitted. (The previous item is removed from the compiled
310			pattern).
311
312			5. Changed all the names of code files so that the basic parts are no longer
313			than 10 characters, and abolished the teeny "globals.c" file.
314
315			6. Changed the handling of character classes; they are now done with a 32-byte
316			bit map always.
317
318			7. Added the -d and /D options to pcretest to make it possible to look at the
319			internals of compilation without having to recompile pcre.
320
321
322			Version 0.95 23-Sep-97
323			----------------------
324
325			1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
326			\x20 at the start of a run of normal characters. These were being treated as
327			real characters, instead of the source characters being re-checked.
328
329
330			Version 0.94 18-Sep-97
331			----------------------
332
333			1. The functions are now thread-safe, with the caveat that the global variables
334			containing pointers to malloc() and free() or alternative functions are the
335			same for all threads.
336
337			2. Get pcre_study() to generate a bitmap of initial characters for non-
338			anchored patterns when this is possible, and use it if passed to pcre_exec().
339
340
341			Version 0.93 15-Sep-97
342			----------------------
343
344			1. /(b)\|(:+)/ was computing an incorrect first character.
345
346			2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
347			but not actually doing anything yet.
348
349			3. Treat "-" characters in classes that cannot be part of ranges as literals,
350			as Perl does (e.g. [-az] or [az-]).
351
352			4. Set the anchored flag if a branch starts with .* or .*? because that tests
353			all possible positions.
354
355			5. Split up into different modules to avoid including unneeded functions in a
356			compiled binary. However, compile and exec are still in one module. The "study"
357			function is split off.
358
359			6. The character tables are now in a separate module whose source is generated
360			by an auxiliary program - but can then be edited by hand if required. There are
361			now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
362			toupper() in the code.
363
364			7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
365			make them global. Abolish the function for setting them, as the caller can now
366			set them directly.
367
368
369			Version 0.92 11-Sep-97
370			----------------------
371
372			1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
373			(e.g. /a{1,3}/) was broken (I mis-optimized it).
374
375			2. Caseless matching was not working in character classes if the characters in
376			the pattern were in upper case.
377
378			3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
379
380			4. Make PCRE_ANCHORED public and accept as a compile option.
381
382			5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
383			PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
384			pass them.
385
386			6. Give an error if bad option bits passed at compile or run time.
387
388			7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
389			pcretest to cause it to pass that flag.
390
391			8. Add pcre_info(), to get the number of identifying subpatterns, the stored
392			options, and the first character, if set.
393
394			9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
395
396
397			Version 0.91 10-Sep-97
398			----------------------
399
400			1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
401			match the empty string as in /(a)/. It was looping and ultimately crashing.
402
403			2. PCRE was looping on encountering an indefinitely repeated back reference to
404			a subpattern that had matched an empty string, e.g. /(a\|)\1*/. It now does what
405			Perl does - treats the match as successful.
406
407			****