Contents of /code/trunk/ChangeLog

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


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	ChangeLog for PCRE
2	------------------
3
4
5	Version 1.02 12-Dec-97
6	----------------------
7
8	1. Typos in pcre.3 and comments in the source fixed.
9
10	2. Applied a contributed patch to get rid of places where it used to remove
11	'const' from variables, and fixed some signed/unsigned and uninitialized
12	variable warnings.
13
14	3. Added the "runtest" target to Makefile.
15
16	4. Set default compiler flag to -O2 rather than just -O.
17
18
19	Version 1.01 19-Nov-97
20	----------------------
21
22	1. PCRE was failing to diagnose unlimited repeat of empty string for patterns
23	like /([ab])/, that is, for classes with more than one character in them.
24
25	2. Likewise, it wasn't diagnosing patterns with "once-only" subpatterns, such
26	as /((?>a))/ (a PCRE_EXTRA facility).
27
28
29	Version 1.00 18-Nov-97
30	----------------------
31
32	1. Added compile-time macros to support systems such as SunOS4 which don't have
33	memmove() or strerror() but have other things that can be used instead.
34
35	2. Arranged that "make clean" removes the executables.
36
37
38	Version 0.99 27-Oct-97
39	----------------------
40
41	1. Fixed bug in code for optimizing classes with only one character. It was
42	initializing a 32-byte map regardless, which could cause it to run off the end
43	of the memory it had got.
44
45	2. Added, conditional on PCRE_EXTRA, the proposed (?>REGEX) construction.
46
47
48	Version 0.98 22-Oct-97
49	----------------------
50
51	1. Fixed bug in code for handling temporary memory usage when there are more
52	back references than supplied space in the ovector. This could cause segfaults.
53
54
55	Version 0.97 21-Oct-97
56	----------------------
57
58	1. Added the \X "cut" facility, conditional on PCRE_EXTRA.
59
60	2. Optimized negated single characters not to use a bit map.
61
62	3. Brought error texts together as macro definitions; clarified some of them;
63	fixed one that was wrong - it said "range out of order" when it meant "invalid
64	escape sequence".
65
66	4. Changed some char * arguments to const char *.
67
68	5. Added PCRE_NOTBOL and PCRE_NOTEOL (from POSIX).
69
70	6. Added the POSIX-style API wrapper in pcreposix.a and testing facilities in
71	pcretest.
72
73
74	Version 0.96 16-Oct-97
75	----------------------
76
77	1. Added a simple "pgrep" utility to the distribution.
78
79	2. Fixed an incompatibility with Perl: "{" is now treated as a normal character
80	unless it appears in one of the precise forms "{ddd}", "{ddd,}", or "{ddd,ddd}"
81	where "ddd" means "one or more decimal digits".
82
83	3. Fixed serious bug. If a pattern had a back reference, but the call to
84	pcre_exec() didn't supply a large enough ovector to record the related
85	identifying subpattern, the match always failed. PCRE now remembers the number
86	of the largest back reference, and gets some temporary memory in which to save
87	the offsets during matching if necessary, in order to ensure that
88	backreferences always work.
89
90	4. Increased the compatibility with Perl in a number of ways:
91
92	(a) . no longer matches \n by default; an option PCRE_DOTALL is provided
93	to request this handling. The option can be set at compile or exec time.
94
95	(b) $ matches before a terminating newline by default; an option
96	PCRE_DOLLAR_ENDONLY is provided to override this (but not in multiline
97	mode). The option can be set at compile or exec time.
98
99	(c) The handling of \ followed by a digit other than 0 is now supposed to be
100	the same as Perl's. If the decimal number it represents is less than 10
101	or there aren't that many previous left capturing parentheses, an octal
102	escape is read. Inside a character class, it's always an octal escape,
103	even if it is a single digit.
104
105	(d) An escaped but undefined alphabetic character is taken as a literal,
106	unless PCRE_EXTRA is set. Currently this just reserves the remaining
107	escapes.
108
109	(e) {0} is now permitted. (The previous item is removed from the compiled
110	pattern).
111
112	5. Changed all the names of code files so that the basic parts are no longer
113	than 10 characters, and abolished the teeny "globals.c" file.
114
115	6. Changed the handling of character classes; they are now done with a 32-byte
116	bit map always.
117
118	7. Added the -d and /D options to pcretest to make it possible to look at the
119	internals of compilation without having to recompile pcre.
120
121
122	Version 0.95 23-Sep-97
123	----------------------
124
125	1. Fixed bug in pre-pass concerning escaped "normal" characters such as \x5c or
126	\x20 at the start of a run of normal characters. These were being treated as
127	real characters, instead of the source characters being re-checked.
128
129
130	Version 0.94 18-Sep-97
131	----------------------
132
133	1. The functions are now thread-safe, with the caveat that the global variables
134	containing pointers to malloc() and free() or alternative functions are the
135	same for all threads.
136
137	2. Get pcre_study() to generate a bitmap of initial characters for non-
138	anchored patterns when this is possible, and use it if passed to pcre_exec().
139
140
141	Version 0.93 15-Sep-97
142	----------------------
143
144	1. /(b)\|(:+)/ was computing an incorrect first character.
145
146	2. Add pcre_study() to the API and the passing of pcre_extra to pcre_exec(),
147	but not actually doing anything yet.
148
149	3. Treat "-" characters in classes that cannot be part of ranges as literals,
150	as Perl does (e.g. [-az] or [az-]).
151
152	4. Set the anchored flag if a branch starts with .* or .*? because that tests
153	all possible positions.
154
155	5. Split up into different modules to avoid including unneeded functions in a
156	compiled binary. However, compile and exec are still in one module. The "study"
157	function is split off.
158
159	6. The character tables are now in a separate module whose source is generated
160	by an auxiliary program - but can then be edited by hand if required. There are
161	now no calls to isalnum(), isspace(), isdigit(), isxdigit(), tolower() or
162	toupper() in the code.
163
164	7. Turn the malloc/free funtions variables into pcre_malloc and pcre_free and
165	make them global. Abolish the function for setting them, as the caller can now
166	set them directly.
167
168
169	Version 0.92 11-Sep-97
170	----------------------
171
172	1. A repeat with a fixed maximum and a minimum of 1 for an ordinary character
173	(e.g. /a{1,3}/) was broken (I mis-optimized it).
174
175	2. Caseless matching was not working in character classes if the characters in
176	the pattern were in upper case.
177
178	3. Make ranges like [W-c] work in the same way as Perl for caseless matching.
179
180	4. Make PCRE_ANCHORED public and accept as a compile option.
181
182	5. Add an options word to pcre_exec() and accept PCRE_ANCHORED and
183	PCRE_CASELESS at run time. Add escapes \A and \I to pcretest to cause it to
184	pass them.
185
186	6. Give an error if bad option bits passed at compile or run time.
187
188	7. Add PCRE_MULTILINE at compile and exec time, and (?m) as well. Add \M to
189	pcretest to cause it to pass that flag.
190
191	8. Add pcre_info(), to get the number of identifying subpatterns, the stored
192	options, and the first character, if set.
193
194	9. Recognize C+ or C{n,m} where n >= 1 as providing a fixed starting character.
195
196
197	Version 0.91 10-Sep-97
198	----------------------
199
200	1. PCRE was failing to diagnose unlimited repeats of subpatterns that could
201	match the empty string as in /(a)/. It was looping and ultimately crashing.
202
203	2. PCRE was looping on encountering an indefinitely repeated back reference to
204	a subpattern that had matched an empty string, e.g. /(a\|)\1*/. It now does what
205	Perl does - treats the match as successful.
206
207	****