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ChangeLog for PCRE |
ChangeLog for PCRE |
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Version 7.5 27-Dec-07 |
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--------------------- |
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1. Applied a patch from Craig: "This patch makes it possible to 'ignore' |
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values in parens when parsing an RE using the C++ wrapper." |
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2. Negative specials like \S did not work in character classes in UTF-8 mode. |
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Characters greater than 255 were excluded from the class instead of being |
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included. |
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|
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3. The same bug as (2) above applied to negated POSIX classes such as |
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[:^space:]. |
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4. PCRECPP_STATIC was referenced in pcrecpp_internal.h, but nowhere was it |
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defined or documented. It seems to have been a typo for PCRE_STATIC, so |
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I have changed it. |
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5. The construct (?&) was not diagnosed as a syntax error (it referenced the |
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first named subpattern) and a construct such as (?&a) would reference the |
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first named subpattern whose name started with "a" (in other words, the |
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length check was missing). Both these problems are fixed. "Subpattern name |
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expected" is now given for (?&) (a zero-length name), and this patch also |
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makes it give the same error for \k'' (previously it complained that that |
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was a reference to a non-existent subpattern). |
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|
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6. The erroneous patterns (?+-a) and (?-+a) give different error messages; |
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this is right because (?- can be followed by option settings as well as by |
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digits. I have, however, made the messages clearer. |
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7. Patterns such as (?(1)a|b) (a pattern that contains fewer subpatterns |
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than the number used in the conditional) now cause a compile-time error. |
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This is actually not compatible with Perl, which accepts such patterns, but |
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treats the conditional as always being FALSE (as PCRE used to), but it |
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seems to me that giving a diagnostic is better. |
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8. Change "alphameric" to the more common word "alphanumeric" in comments |
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and messages. |
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9. Fix two occurrences of "backslash" in comments that should have been |
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"backspace". |
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10. Remove two redundant lines of code that can never be obeyed (their function |
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was moved elsewhere). |
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11. The program that makes PCRE's Unicode character property table had a bug |
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which caused it to generate incorrect table entries for sequences of |
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characters that have the same character type, but are in different scripts. |
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It amalgamated them into a single range, with the script of the first of |
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them. In other words, some characters were in the wrong script. There were |
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thirteen such cases, affecting characters in the following ranges: |
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|
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U+002b0 - U+002c1 |
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U+0060c - U+0060d |
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U+0061e - U+00612 |
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U+0064b - U+0065e |
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U+0074d - U+0076d |
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U+01800 - U+01805 |
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U+01d00 - U+01d77 |
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U+01d9b - U+01dbf |
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U+0200b - U+0200f |
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U+030fc - U+030fe |
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U+03260 - U+0327f |
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U+0fb46 - U+0fbb1 |
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U+10450 - U+1049d |
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12. The -o option (show only the matching part of a line) for pcregrep was not |
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compatible with GNU grep in that, if there was more than one match in a |
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line, it showed only the first of them. It now behaves in the same way as |
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GNU grep. |
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13. If the -o and -v options were combined for pcregrep, it printed a blank |
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line for every non-matching line. GNU grep prints nothing, and pcregrep now |
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does the same. The return code can be used to tell if there were any |
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non-matching lines. |
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14. Added --file-offsets and --line-offsets to pcregrep. |
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15. The pattern (?=something)(?R) was not being diagnosed as a potentially |
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infinitely looping recursion. The bug was that positive lookaheads were not |
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being skipped when checking for a possible empty match (negative lookaheads |
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and both kinds of lookbehind were skipped). |
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16. Fixed two typos in the Windows-only code in pcregrep.c, and moved the |
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inclusion of <windows.h> to before rather than after the definition of |
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INVALID_FILE_ATTRIBUTES (patch from David Byron). |
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17. Specifying a possessive quantifier with a specific limit for a Unicode |
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character property caused pcre_compile() to compile bad code, which led at |
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runtime to PCRE_ERROR_INTERNAL (-14). Examples of patterns that caused this |
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are: /\p{Zl}{2,3}+/8 and /\p{Cc}{2}+/8. It was the possessive "+" that |
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caused the error; without that there was no problem. |
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18. Added --enable-pcregrep-libz and --enable-pcregrep-libbz2. |
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19. Added --enable-pcretest-libreadline. |
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20. In pcrecpp.cc, the variable 'count' was incremented twice in |
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RE::GlobalReplace(). As a result, the number of replacements returned was |
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double what it should be. I have removed one of the increments. |
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21. Several CMake things: |
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(1) Arranged that, when cmake is used on Unix, the libraries end up with |
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the names libpcre and libpcreposix, not just pcre and pcreposix. |
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(2) The above change means that pcretest and pcregrep are now correctly |
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linked with the newly-built libraries, not previously installed ones. |
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(3) Added PCRE_SUPPORT_LIBREADLINE, PCRE_SUPPORT_LIBZ, PCRE_SUPPORT_LIBBZ2. |
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Version 7.4 21-Sep-07 |
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--------------------- |
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1. Change 7.3/28 was implemented for classes by looking at the bitmap. This |
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means that a class such as [\s] counted as "explicit reference to CR or |
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LF". That isn't really right - the whole point of the change was to try to |
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help when there was an actual mention of one of the two characters. So now |
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the change happens only if \r or \n (or a literal CR or LF) character is |
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encountered. |
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2. The 32-bit options word was also used for 6 internal flags, but the numbers |
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of both had grown to the point where there were only 3 bits left. |
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Fortunately, there was spare space in the data structure, and so I have |
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moved the internal flags into a new 16-bit field to free up more option |
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bits. |
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3. The appearance of (?J) at the start of a pattern set the DUPNAMES option, |
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but did not set the internal JCHANGED flag - either of these is enough to |
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control the way the "get" function works - but the PCRE_INFO_JCHANGED |
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facility is supposed to tell if (?J) was ever used, so now (?J) at the |
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start sets both bits. |
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4. Added options (at build time, compile time, exec time) to change \R from |
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matching any Unicode line ending sequence to just matching CR, LF, or CRLF. |
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5. doc/pcresyntax.html was missing from the distribution. |
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6. Put back the definition of PCRE_ERROR_NULLWSLIMIT, for backward |
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compatibility, even though it is no longer used. |
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7. Added macro for snprintf to pcrecpp_unittest.cc and also for strtoll and |
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strtoull to pcrecpp.cc to select the available functions in WIN32 when the |
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windows.h file is present (where different names are used). [This was |
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reversed later after testing - see 16 below.] |
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|
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8. Changed all #include <config.h> to #include "config.h". There were also |
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some further <pcre.h> cases that I changed to "pcre.h". |
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|
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9. When pcregrep was used with the --colour option, it missed the line ending |
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sequence off the lines that it output. |
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10. It was pointed out to me that arrays of string pointers cause lots of |
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relocations when a shared library is dynamically loaded. A technique of |
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using a single long string with a table of offsets can drastically reduce |
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these. I have refactored PCRE in four places to do this. The result is |
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dramatic: |
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|
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Originally: 290 |
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After changing UCP table: 187 |
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After changing error message table: 43 |
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After changing table of "verbs" 36 |
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After changing table of Posix names 22 |
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Thanks to the folks working on Gregex for glib for this insight. |
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11. --disable-stack-for-recursion caused compiling to fail unless -enable- |
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unicode-properties was also set. |
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12. Updated the tests so that they work when \R is defaulted to ANYCRLF. |
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13. Added checks for ANY and ANYCRLF to pcrecpp.cc where it previously |
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checked only for CRLF. |
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14. Added casts to pcretest.c to avoid compiler warnings. |
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15. Added Craig's patch to various pcrecpp modules to avoid compiler warnings. |
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16. Added Craig's patch to remove the WINDOWS_H tests, that were not working, |
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and instead check for _strtoi64 explicitly, and avoid the use of snprintf() |
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entirely. This removes changes made in 7 above. |
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17. The CMake files have been updated, and there is now more information about |
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building with CMake in the NON-UNIX-USE document. |
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Version 7.3 28-Aug-07 |
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--------------------- |
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1. In the rejigging of the build system that eventually resulted in 7.1, the |
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line "#include <pcre.h>" was included in pcre_internal.h. The use of angle |
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brackets there is not right, since it causes compilers to look for an |
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installed pcre.h, not the version that is in the source that is being |
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compiled (which of course may be different). I have changed it back to: |
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#include "pcre.h" |
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I have a vague recollection that the change was concerned with compiling in |
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different directories, but in the new build system, that is taken care of |
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by the VPATH setting the Makefile. |
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2. The pattern .*$ when run in not-DOTALL UTF-8 mode with newline=any failed |
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when the subject happened to end in the byte 0x85 (e.g. if the last |
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character was \x{1ec5}). *Character* 0x85 is one of the "any" newline |
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characters but of course it shouldn't be taken as a newline when it is part |
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of another character. The bug was that, for an unlimited repeat of . in |
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not-DOTALL UTF-8 mode, PCRE was advancing by bytes rather than by |
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characters when looking for a newline. |
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3. A small performance improvement in the DOTALL UTF-8 mode .* case. |
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4. Debugging: adjusted the names of opcodes for different kinds of parentheses |
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in debug output. |
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5. Arrange to use "%I64d" instead of "%lld" and "%I64u" instead of "%llu" for |
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long printing in the pcrecpp unittest when running under MinGW. |
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6. ESC_K was left out of the EBCDIC table. |
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7. Change 7.0/38 introduced a new limit on the number of nested non-capturing |
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parentheses; I made it 1000, which seemed large enough. Unfortunately, the |
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limit also applies to "virtual nesting" when a pattern is recursive, and in |
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this case 1000 isn't so big. I have been able to remove this limit at the |
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expense of backing off one optimization in certain circumstances. Normally, |
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when pcre_exec() would call its internal match() function recursively and |
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immediately return the result unconditionally, it uses a "tail recursion" |
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feature to save stack. However, when a subpattern that can match an empty |
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string has an unlimited repetition quantifier, it no longer makes this |
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optimization. That gives it a stack frame in which to save the data for |
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checking that an empty string has been matched. Previously this was taken |
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from the 1000-entry workspace that had been reserved. So now there is no |
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explicit limit, but more stack is used. |
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8. Applied Daniel's patches to solve problems with the import/export magic |
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syntax that is required for Windows, and which was going wrong for the |
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pcreposix and pcrecpp parts of the library. These were overlooked when this |
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problem was solved for the main library. |
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9. There were some crude static tests to avoid integer overflow when computing |
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the size of patterns that contain repeated groups with explicit upper |
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limits. As the maximum quantifier is 65535, the maximum group length was |
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set at 30,000 so that the product of these two numbers did not overflow a |
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32-bit integer. However, it turns out that people want to use groups that |
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are longer than 30,000 bytes (though not repeat them that many times). |
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Change 7.0/17 (the refactoring of the way the pattern size is computed) has |
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made it possible to implement the integer overflow checks in a much more |
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dynamic way, which I have now done. The artificial limitation on group |
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length has been removed - we now have only the limit on the total length of |
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the compiled pattern, which depends on the LINK_SIZE setting. |
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10. Fixed a bug in the documentation for get/copy named substring when |
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duplicate names are permitted. If none of the named substrings are set, the |
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functions return PCRE_ERROR_NOSUBSTRING (7); the doc said they returned an |
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empty string. |
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11. Because Perl interprets \Q...\E at a high level, and ignores orphan \E |
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instances, patterns such as [\Q\E] or [\E] or even [^\E] cause an error, |
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because the ] is interpreted as the first data character and the |
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terminating ] is not found. PCRE has been made compatible with Perl in this |
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regard. Previously, it interpreted [\Q\E] as an empty class, and [\E] could |
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cause memory overwriting. |
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|
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10. Like Perl, PCRE automatically breaks an unlimited repeat after an empty |
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string has been matched (to stop an infinite loop). It was not recognizing |
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a conditional subpattern that could match an empty string if that |
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subpattern was within another subpattern. For example, it looped when |
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trying to match (((?(1)X|))*) but it was OK with ((?(1)X|)*) where the |
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condition was not nested. This bug has been fixed. |
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12. A pattern like \X?\d or \P{L}?\d in non-UTF-8 mode could cause a backtrack |
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past the start of the subject in the presence of bytes with the top bit |
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set, for example "\x8aBCD". |
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13. Added Perl 5.10 experimental backtracking controls (*FAIL), (*F), (*PRUNE), |
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(*SKIP), (*THEN), (*COMMIT), and (*ACCEPT). |
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14. Optimized (?!) to (*FAIL). |
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15. Updated the test for a valid UTF-8 string to conform to the later RFC 3629. |
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This restricts code points to be within the range 0 to 0x10FFFF, excluding |
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the "low surrogate" sequence 0xD800 to 0xDFFF. Previously, PCRE allowed the |
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full range 0 to 0x7FFFFFFF, as defined by RFC 2279. Internally, it still |
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does: it's just the validity check that is more restrictive. |
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16. Inserted checks for integer overflows during escape sequence (backslash) |
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processing, and also fixed erroneous offset values for syntax errors during |
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backslash processing. |
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17. Fixed another case of looking too far back in non-UTF-8 mode (cf 12 above) |
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for patterns like [\PPP\x8a]{1,}\x80 with the subject "A\x80". |
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|
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18. An unterminated class in a pattern like (?1)\c[ with a "forward reference" |
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caused an overrun. |
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|
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19. A pattern like (?:[\PPa*]*){8,} which had an "extended class" (one with |
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something other than just ASCII characters) inside a group that had an |
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unlimited repeat caused a loop at compile time (while checking to see |
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whether the group could match an empty string). |
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|
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20. Debugging a pattern containing \p or \P could cause a crash. For example, |
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[\P{Any}] did so. (Error in the code for printing property names.) |
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|
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21. An orphan \E inside a character class could cause a crash. |
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22. A repeated capturing bracket such as (A)? could cause a wild memory |
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reference during compilation. |
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23. There are several functions in pcre_compile() that scan along a compiled |
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expression for various reasons (e.g. to see if it's fixed length for look |
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behind). There were bugs in these functions when a repeated \p or \P was |
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present in the pattern. These operators have additional parameters compared |
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with \d, etc, and these were not being taken into account when moving along |
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the compiled data. Specifically: |
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|
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(a) A item such as \p{Yi}{3} in a lookbehind was not treated as fixed |
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length. |
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|
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(b) An item such as \pL+ within a repeated group could cause crashes or |
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loops. |
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|
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(c) A pattern such as \p{Yi}+(\P{Yi}+)(?1) could give an incorrect |
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"reference to non-existent subpattern" error. |
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(d) A pattern like (\P{Yi}{2}\277)? could loop at compile time. |
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|
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24. A repeated \S or \W in UTF-8 mode could give wrong answers when multibyte |
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characters were involved (for example /\S{2}/8g with "A\x{a3}BC"). |
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|
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25. Using pcregrep in multiline, inverted mode (-Mv) caused it to loop. |
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26. Patterns such as [\P{Yi}A] which include \p or \P and just one other |
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character were causing crashes (broken optimization). |
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27. Patterns such as (\P{Yi}*\277)* (group with possible zero repeat containing |
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\p or \P) caused a compile-time loop. |
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|
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28. More problems have arisen in unanchored patterns when CRLF is a valid line |
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break. For example, the unstudied pattern [\r\n]A does not match the string |
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"\r\nA" because change 7.0/46 below moves the current point on by two |
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characters after failing to match at the start. However, the pattern \nA |
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*does* match, because it doesn't start till \n, and if [\r\n]A is studied, |
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the same is true. There doesn't seem any very clean way out of this, but |
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what I have chosen to do makes the common cases work: PCRE now takes note |
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of whether there can be an explicit match for \r or \n anywhere in the |
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pattern, and if so, 7.0/46 no longer applies. As part of this change, |
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there's a new PCRE_INFO_HASCRORLF option for finding out whether a compiled |
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pattern has explicit CR or LF references. |
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|
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29. Added (*CR) etc for changing newline setting at start of pattern. |
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Version 7.2 19-Jun-07 |
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--------------------- |
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|
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1. If the fr_FR locale cannot be found for test 3, try the "french" locale, |
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which is apparently normally available under Windows. |
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|
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2. Re-jig the pcregrep tests with different newline settings in an attempt |
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to make them independent of the local environment's newline setting. |
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3. Add code to configure.ac to remove -g from the CFLAGS default settings. |
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|
| 366 |
|
4. Some of the "internals" tests were previously cut out when the link size |
| 367 |
|
was not 2, because the output contained actual offsets. The recent new |
| 368 |
|
"Z" feature of pcretest means that these can be cut out, making the tests |
| 369 |
|
usable with all link sizes. |
| 370 |
|
|
| 371 |
|
5. Implemented Stan Switzer's goto replacement for longjmp() when not using |
| 372 |
|
stack recursion. This gives a massive performance boost under BSD, but just |
| 373 |
|
a small improvement under Linux. However, it saves one field in the frame |
| 374 |
|
in all cases. |
| 375 |
|
|
| 376 |
|
6. Added more features from the forthcoming Perl 5.10: |
| 377 |
|
|
| 378 |
|
(a) (?-n) (where n is a string of digits) is a relative subroutine or |
| 379 |
|
recursion call. It refers to the nth most recently opened parentheses. |
| 380 |
|
|
| 381 |
|
(b) (?+n) is also a relative subroutine call; it refers to the nth next |
| 382 |
|
to be opened parentheses. |
| 383 |
|
|
| 384 |
|
(c) Conditions that refer to capturing parentheses can be specified |
| 385 |
|
relatively, for example, (?(-2)... or (?(+3)... |
| 386 |
|
|
| 387 |
|
(d) \K resets the start of the current match so that everything before |
| 388 |
|
is not part of it. |
| 389 |
|
|
| 390 |
|
(e) \k{name} is synonymous with \k<name> and \k'name' (.NET compatible). |
| 391 |
|
|
| 392 |
|
(f) \g{name} is another synonym - part of Perl 5.10's unification of |
| 393 |
|
reference syntax. |
| 394 |
|
|
| 395 |
|
(g) (?| introduces a group in which the numbering of parentheses in each |
| 396 |
|
alternative starts with the same number. |
| 397 |
|
|
| 398 |
|
(h) \h, \H, \v, and \V match horizontal and vertical whitespace. |
| 399 |
|
|
| 400 |
|
7. Added two new calls to pcre_fullinfo(): PCRE_INFO_OKPARTIAL and |
| 401 |
|
PCRE_INFO_JCHANGED. |
| 402 |
|
|
| 403 |
|
8. A pattern such as (.*(.)?)* caused pcre_exec() to fail by either not |
| 404 |
|
terminating or by crashing. Diagnosed by Viktor Griph; it was in the code |
| 405 |
|
for detecting groups that can match an empty string. |
| 406 |
|
|
| 407 |
|
9. A pattern with a very large number of alternatives (more than several |
| 408 |
|
hundred) was running out of internal workspace during the pre-compile |
| 409 |
|
phase, where pcre_compile() figures out how much memory will be needed. A |
| 410 |
|
bit of new cunning has reduced the workspace needed for groups with |
| 411 |
|
alternatives. The 1000-alternative test pattern now uses 12 bytes of |
| 412 |
|
workspace instead of running out of the 4096 that are available. |
| 413 |
|
|
| 414 |
|
10. Inserted some missing (unsigned int) casts to get rid of compiler warnings. |
| 415 |
|
|
| 416 |
|
11. Applied patch from Google to remove an optimization that didn't quite work. |
| 417 |
|
The report of the bug said: |
| 418 |
|
|
| 419 |
|
pcrecpp::RE("a*").FullMatch("aaa") matches, while |
| 420 |
|
pcrecpp::RE("a*?").FullMatch("aaa") does not, and |
| 421 |
|
pcrecpp::RE("a*?\\z").FullMatch("aaa") does again. |
| 422 |
|
|
| 423 |
|
12. If \p or \P was used in non-UTF-8 mode on a character greater than 127 |
| 424 |
|
it matched the wrong number of bytes. |
| 425 |
|
|
| 426 |
|
|
| 427 |
|
Version 7.1 24-Apr-07 |
| 428 |
|
--------------------- |
| 429 |
|
|
| 430 |
|
1. Applied Bob Rossi and Daniel G's patches to convert the build system to one |
| 431 |
|
that is more "standard", making use of automake and other Autotools. There |
| 432 |
|
is some re-arrangement of the files and adjustment of comments consequent |
| 433 |
|
on this. |
| 434 |
|
|
| 435 |
|
2. Part of the patch fixed a problem with the pcregrep tests. The test of -r |
| 436 |
|
for recursive directory scanning broke on some systems because the files |
| 437 |
|
are not scanned in any specific order and on different systems the order |
| 438 |
|
was different. A call to "sort" has been inserted into RunGrepTest for the |
| 439 |
|
approprate test as a short-term fix. In the longer term there may be an |
| 440 |
|
alternative. |
| 441 |
|
|
| 442 |
|
3. I had an email from Eric Raymond about problems translating some of PCRE's |
| 443 |
|
man pages to HTML (despite the fact that I distribute HTML pages, some |
| 444 |
|
people do their own conversions for various reasons). The problems |
| 445 |
|
concerned the use of low-level troff macros .br and .in. I have therefore |
| 446 |
|
removed all such uses from the man pages (some were redundant, some could |
| 447 |
|
be replaced by .nf/.fi pairs). The 132html script that I use to generate |
| 448 |
|
HTML has been updated to handle .nf/.fi and to complain if it encounters |
| 449 |
|
.br or .in. |
| 450 |
|
|
| 451 |
|
4. Updated comments in configure.ac that get placed in config.h.in and also |
| 452 |
|
arranged for config.h to be included in the distribution, with the name |
| 453 |
|
config.h.generic, for the benefit of those who have to compile without |
| 454 |
|
Autotools (compare pcre.h, which is now distributed as pcre.h.generic). |
| 455 |
|
|
| 456 |
|
5. Updated the support (such as it is) for Virtual Pascal, thanks to Stefan |
| 457 |
|
Weber: (1) pcre_internal.h was missing some function renames; (2) updated |
| 458 |
|
makevp.bat for the current PCRE, using the additional files |
| 459 |
|
makevp_c.txt, makevp_l.txt, and pcregexp.pas. |
| 460 |
|
|
| 461 |
|
6. A Windows user reported a minor discrepancy with test 2, which turned out |
| 462 |
|
to be caused by a trailing space on an input line that had got lost in his |
| 463 |
|
copy. The trailing space was an accident, so I've just removed it. |
| 464 |
|
|
| 465 |
|
7. Add -Wl,-R... flags in pcre-config.in for *BSD* systems, as I'm told |
| 466 |
|
that is needed. |
| 467 |
|
|
| 468 |
|
8. Mark ucp_table (in ucptable.h) and ucp_gentype (in pcre_ucp_searchfuncs.c) |
| 469 |
|
as "const" (a) because they are and (b) because it helps the PHP |
| 470 |
|
maintainers who have recently made a script to detect big data structures |
| 471 |
|
in the php code that should be moved to the .rodata section. I remembered |
| 472 |
|
to update Builducptable as well, so it won't revert if ucptable.h is ever |
| 473 |
|
re-created. |
| 474 |
|
|
| 475 |
|
9. Added some extra #ifdef SUPPORT_UTF8 conditionals into pcretest.c, |
| 476 |
|
pcre_printint.src, pcre_compile.c, pcre_study.c, and pcre_tables.c, in |
| 477 |
|
order to be able to cut out the UTF-8 tables in the latter when UTF-8 |
| 478 |
|
support is not required. This saves 1.5-2K of code, which is important in |
| 479 |
|
some applications. |
| 480 |
|
|
| 481 |
|
Later: more #ifdefs are needed in pcre_ord2utf8.c and pcre_valid_utf8.c |
| 482 |
|
so as not to refer to the tables, even though these functions will never be |
| 483 |
|
called when UTF-8 support is disabled. Otherwise there are problems with a |
| 484 |
|
shared library. |
| 485 |
|
|
| 486 |
|
10. Fixed two bugs in the emulated memmove() function in pcre_internal.h: |
| 487 |
|
|
| 488 |
|
(a) It was defining its arguments as char * instead of void *. |
| 489 |
|
|
| 490 |
|
(b) It was assuming that all moves were upwards in memory; this was true |
| 491 |
|
a long time ago when I wrote it, but is no longer the case. |
| 492 |
|
|
| 493 |
|
The emulated memove() is provided for those environments that have neither |
| 494 |
|
memmove() nor bcopy(). I didn't think anyone used it these days, but that |
| 495 |
|
is clearly not the case, as these two bugs were recently reported. |
| 496 |
|
|
| 497 |
|
11. The script PrepareRelease is now distributed: it calls 132html, CleanTxt, |
| 498 |
|
and Detrail to create the HTML documentation, the .txt form of the man |
| 499 |
|
pages, and it removes trailing spaces from listed files. It also creates |
| 500 |
|
pcre.h.generic and config.h.generic from pcre.h and config.h. In the latter |
| 501 |
|
case, it wraps all the #defines with #ifndefs. This script should be run |
| 502 |
|
before "make dist". |
| 503 |
|
|
| 504 |
|
12. Fixed two fairly obscure bugs concerned with quantified caseless matching |
| 505 |
|
with Unicode property support. |
| 506 |
|
|
| 507 |
|
(a) For a maximizing quantifier, if the two different cases of the |
| 508 |
|
character were of different lengths in their UTF-8 codings (there are |
| 509 |
|
some cases like this - I found 11), and the matching function had to |
| 510 |
|
back up over a mixture of the two cases, it incorrectly assumed they |
| 511 |
|
were both the same length. |
| 512 |
|
|
| 513 |
|
(b) When PCRE was configured to use the heap rather than the stack for |
| 514 |
|
recursion during matching, it was not correctly preserving the data for |
| 515 |
|
the other case of a UTF-8 character when checking ahead for a match |
| 516 |
|
while processing a minimizing repeat. If the check also involved |
| 517 |
|
matching a wide character, but failed, corruption could cause an |
| 518 |
|
erroneous result when trying to check for a repeat of the original |
| 519 |
|
character. |
| 520 |
|
|
| 521 |
|
13. Some tidying changes to the testing mechanism: |
| 522 |
|
|
| 523 |
|
(a) The RunTest script now detects the internal link size and whether there |
| 524 |
|
is UTF-8 and UCP support by running ./pcretest -C instead of relying on |
| 525 |
|
values substituted by "configure". (The RunGrepTest script already did |
| 526 |
|
this for UTF-8.) The configure.ac script no longer substitutes the |
| 527 |
|
relevant variables. |
| 528 |
|
|
| 529 |
|
(b) The debugging options /B and /D in pcretest show the compiled bytecode |
| 530 |
|
with length and offset values. This means that the output is different |
| 531 |
|
for different internal link sizes. Test 2 is skipped for link sizes |
| 532 |
|
other than 2 because of this, bypassing the problem. Unfortunately, |
| 533 |
|
there was also a test in test 3 (the locale tests) that used /B and |
| 534 |
|
failed for link sizes other than 2. Rather than cut the whole test out, |
| 535 |
|
I have added a new /Z option to pcretest that replaces the length and |
| 536 |
|
offset values with spaces. This is now used to make test 3 independent |
| 537 |
|
of link size. (Test 2 will be tidied up later.) |
| 538 |
|
|
| 539 |
|
14. If erroroffset was passed as NULL to pcre_compile, it provoked a |
| 540 |
|
segmentation fault instead of returning the appropriate error message. |
| 541 |
|
|
| 542 |
|
15. In multiline mode when the newline sequence was set to "any", the pattern |
| 543 |
|
^$ would give a match between the \r and \n of a subject such as "A\r\nB". |
| 544 |
|
This doesn't seem right; it now treats the CRLF combination as the line |
| 545 |
|
ending, and so does not match in that case. It's only a pattern such as ^$ |
| 546 |
|
that would hit this one: something like ^ABC$ would have failed after \r |
| 547 |
|
and then tried again after \r\n. |
| 548 |
|
|
| 549 |
|
16. Changed the comparison command for RunGrepTest from "diff -u" to "diff -ub" |
| 550 |
|
in an attempt to make files that differ only in their line terminators |
| 551 |
|
compare equal. This works on Linux. |
| 552 |
|
|
| 553 |
|
17. Under certain error circumstances pcregrep might try to free random memory |
| 554 |
|
as it exited. This is now fixed, thanks to valgrind. |
| 555 |
|
|
| 556 |
|
19. In pcretest, if the pattern /(?m)^$/g<any> was matched against the string |
| 557 |
|
"abc\r\n\r\n", it found an unwanted second match after the second \r. This |
| 558 |
|
was because its rules for how to advance for /g after matching an empty |
| 559 |
|
string at the end of a line did not allow for this case. They now check for |
| 560 |
|
it specially. |
| 561 |
|
|
| 562 |
|
20. pcretest is supposed to handle patterns and data of any length, by |
| 563 |
|
extending its buffers when necessary. It was getting this wrong when the |
| 564 |
|
buffer for a data line had to be extended. |
| 565 |
|
|
| 566 |
|
21. Added PCRE_NEWLINE_ANYCRLF which is like ANY, but matches only CR, LF, or |
| 567 |
|
CRLF as a newline sequence. |
| 568 |
|
|
| 569 |
|
22. Code for handling Unicode properties in pcre_dfa_exec() wasn't being cut |
| 570 |
|
out by #ifdef SUPPORT_UCP. This did no harm, as it could never be used, but |
| 571 |
|
I have nevertheless tidied it up. |
| 572 |
|
|
| 573 |
|
23. Added some casts to kill warnings from HP-UX ia64 compiler. |
| 574 |
|
|
| 575 |
|
24. Added a man page for pcre-config. |
| 576 |
|
|
| 577 |
|
|
| 578 |
|
Version 7.0 19-Dec-06 |
| 579 |
|
--------------------- |
| 580 |
|
|
| 581 |
|
1. Fixed a signed/unsigned compiler warning in pcre_compile.c, shown up by |
| 582 |
|
moving to gcc 4.1.1. |
| 583 |
|
|
| 584 |
|
2. The -S option for pcretest uses setrlimit(); I had omitted to #include |
| 585 |
|
sys/time.h, which is documented as needed for this function. It doesn't |
| 586 |
|
seem to matter on Linux, but it showed up on some releases of OS X. |
| 587 |
|
|
| 588 |
|
3. It seems that there are systems where bytes whose values are greater than |
| 589 |
|
127 match isprint() in the "C" locale. The "C" locale should be the |
| 590 |
|
default when a C program starts up. In most systems, only ASCII printing |
| 591 |
|
characters match isprint(). This difference caused the output from pcretest |
| 592 |
|
to vary, making some of the tests fail. I have changed pcretest so that: |
| 593 |
|
|
| 594 |
|
(a) When it is outputting text in the compiled version of a pattern, bytes |
| 595 |
|
other than 32-126 are always shown as hex escapes. |
| 596 |
|
|
| 597 |
|
(b) When it is outputting text that is a matched part of a subject string, |
| 598 |
|
it does the same, unless a different locale has been set for the match |
| 599 |
|
(using the /L modifier). In this case, it uses isprint() to decide. |
| 600 |
|
|
| 601 |
|
4. Fixed a major bug that caused incorrect computation of the amount of memory |
| 602 |
|
required for a compiled pattern when options that changed within the |
| 603 |
|
pattern affected the logic of the preliminary scan that determines the |
| 604 |
|
length. The relevant options are -x, and -i in UTF-8 mode. The result was |
| 605 |
|
that the computed length was too small. The symptoms of this bug were |
| 606 |
|
either the PCRE error "internal error: code overflow" from pcre_compile(), |
| 607 |
|
or a glibc crash with a message such as "pcretest: free(): invalid next |
| 608 |
|
size (fast)". Examples of patterns that provoked this bug (shown in |
| 609 |
|
pcretest format) are: |
| 610 |
|
|
| 611 |
|
/(?-x: )/x |
| 612 |
|
/(?x)(?-x: \s*#\s*)/ |
| 613 |
|
/((?i)[\x{c0}])/8 |
| 614 |
|
/(?i:[\x{c0}])/8 |
| 615 |
|
|
| 616 |
|
HOWEVER: Change 17 below makes this fix obsolete as the memory computation |
| 617 |
|
is now done differently. |
| 618 |
|
|
| 619 |
|
5. Applied patches from Google to: (a) add a QuoteMeta function to the C++ |
| 620 |
|
wrapper classes; (b) implement a new function in the C++ scanner that is |
| 621 |
|
more efficient than the old way of doing things because it avoids levels of |
| 622 |
|
recursion in the regex matching; (c) add a paragraph to the documentation |
| 623 |
|
for the FullMatch() function. |
| 624 |
|
|
| 625 |
|
6. The escape sequence \n was being treated as whatever was defined as |
| 626 |
|
"newline". Not only was this contrary to the documentation, which states |
| 627 |
|
that \n is character 10 (hex 0A), but it also went horribly wrong when |
| 628 |
|
"newline" was defined as CRLF. This has been fixed. |
| 629 |
|
|
| 630 |
|
7. In pcre_dfa_exec.c the value of an unsigned integer (the variable called c) |
| 631 |
|
was being set to -1 for the "end of line" case (supposedly a value that no |
| 632 |
|
character can have). Though this value is never used (the check for end of |
| 633 |
|
line is "zero bytes in current character"), it caused compiler complaints. |
| 634 |
|
I've changed it to 0xffffffff. |
| 635 |
|
|
| 636 |
|
8. In pcre_version.c, the version string was being built by a sequence of |
| 637 |
|
C macros that, in the event of PCRE_PRERELEASE being defined as an empty |
| 638 |
|
string (as it is for production releases) called a macro with an empty |
| 639 |
|
argument. The C standard says the result of this is undefined. The gcc |
| 640 |
|
compiler treats it as an empty string (which was what was wanted) but it is |
| 641 |
|
reported that Visual C gives an error. The source has been hacked around to |
| 642 |
|
avoid this problem. |
| 643 |
|
|
| 644 |
|
9. On the advice of a Windows user, included <io.h> and <fcntl.h> in Windows |
| 645 |
|
builds of pcretest, and changed the call to _setmode() to use _O_BINARY |
| 646 |
|
instead of 0x8000. Made all the #ifdefs test both _WIN32 and WIN32 (not all |
| 647 |
|
of them did). |
| 648 |
|
|
| 649 |
|
10. Originally, pcretest opened its input and output without "b"; then I was |
| 650 |
|
told that "b" was needed in some environments, so it was added for release |
| 651 |
|
5.0 to both the input and output. (It makes no difference on Unix-like |
| 652 |
|
systems.) Later I was told that it is wrong for the input on Windows. I've |
| 653 |
|
now abstracted the modes into two macros, to make it easier to fiddle with |
| 654 |
|
them, and removed "b" from the input mode under Windows. |
| 655 |
|
|
| 656 |
|
11. Added pkgconfig support for the C++ wrapper library, libpcrecpp. |
| 657 |
|
|
| 658 |
|
12. Added -help and --help to pcretest as an official way of being reminded |
| 659 |
|
of the options. |
| 660 |
|
|
| 661 |
|
13. Removed some redundant semicolons after macro calls in pcrecpparg.h.in |
| 662 |
|
and pcrecpp.cc because they annoy compilers at high warning levels. |
| 663 |
|
|
| 664 |
|
14. A bit of tidying/refactoring in pcre_exec.c in the main bumpalong loop. |
| 665 |
|
|
| 666 |
|
15. Fixed an occurrence of == in configure.ac that should have been = (shell |
| 667 |
|
scripts are not C programs :-) and which was not noticed because it works |
| 668 |
|
on Linux. |
| 669 |
|
|
| 670 |
|
16. pcretest is supposed to handle any length of pattern and data line (as one |
| 671 |
|
line or as a continued sequence of lines) by extending its input buffer if |
| 672 |
|
necessary. This feature was broken for very long pattern lines, leading to |
| 673 |
|
a string of junk being passed to pcre_compile() if the pattern was longer |
| 674 |
|
than about 50K. |
| 675 |
|
|
| 676 |
|
17. I have done a major re-factoring of the way pcre_compile() computes the |
| 677 |
|
amount of memory needed for a compiled pattern. Previously, there was code |
| 678 |
|
that made a preliminary scan of the pattern in order to do this. That was |
| 679 |
|
OK when PCRE was new, but as the facilities have expanded, it has become |
| 680 |
|
harder and harder to keep it in step with the real compile phase, and there |
| 681 |
|
have been a number of bugs (see for example, 4 above). I have now found a |
| 682 |
|
cunning way of running the real compile function in a "fake" mode that |
| 683 |
|
enables it to compute how much memory it would need, while actually only |
| 684 |
|
ever using a few hundred bytes of working memory and without too many |
| 685 |
|
tests of the mode. This should make future maintenance and development |
| 686 |
|
easier. A side effect of this work is that the limit of 200 on the nesting |
| 687 |
|
depth of parentheses has been removed (though this was never a serious |
| 688 |
|
limitation, I suspect). However, there is a downside: pcre_compile() now |
| 689 |
|
runs more slowly than before (30% or more, depending on the pattern). I |
| 690 |
|
hope this isn't a big issue. There is no effect on runtime performance. |
| 691 |
|
|
| 692 |
|
18. Fixed a minor bug in pcretest: if a pattern line was not terminated by a |
| 693 |
|
newline (only possible for the last line of a file) and it was a |
| 694 |
|
pattern that set a locale (followed by /Lsomething), pcretest crashed. |
| 695 |
|
|
| 696 |
|
19. Added additional timing features to pcretest. (1) The -tm option now times |
| 697 |
|
matching only, not compiling. (2) Both -t and -tm can be followed, as a |
| 698 |
|
separate command line item, by a number that specifies the number of |
| 699 |
|
repeats to use when timing. The default is 50000; this gives better |
| 700 |
|
precision, but takes uncomfortably long for very large patterns. |
| 701 |
|
|
| 702 |
|
20. Extended pcre_study() to be more clever in cases where a branch of a |
| 703 |
|
subpattern has no definite first character. For example, (a*|b*)[cd] would |
| 704 |
|
previously give no result from pcre_study(). Now it recognizes that the |
| 705 |
|
first character must be a, b, c, or d. |
| 706 |
|
|
| 707 |
|
21. There was an incorrect error "recursive call could loop indefinitely" if |
| 708 |
|
a subpattern (or the entire pattern) that was being tested for matching an |
| 709 |
|
empty string contained only one non-empty item after a nested subpattern. |
| 710 |
|
For example, the pattern (?>\x{100}*)\d(?R) provoked this error |
| 711 |
|
incorrectly, because the \d was being skipped in the check. |
| 712 |
|
|
| 713 |
|
22. The pcretest program now has a new pattern option /B and a command line |
| 714 |
|
option -b, which is equivalent to adding /B to every pattern. This causes |
| 715 |
|
it to show the compiled bytecode, without the additional information that |
| 716 |
|
-d shows. The effect of -d is now the same as -b with -i (and similarly, /D |
| 717 |
|
is the same as /B/I). |
| 718 |
|
|
| 719 |
|
23. A new optimization is now able automatically to treat some sequences such |
| 720 |
|
as a*b as a*+b. More specifically, if something simple (such as a character |
| 721 |
|
or a simple class like \d) has an unlimited quantifier, and is followed by |
| 722 |
|
something that cannot possibly match the quantified thing, the quantifier |
| 723 |
|
is automatically "possessified". |
| 724 |
|
|
| 725 |
|
24. A recursive reference to a subpattern whose number was greater than 39 |
| 726 |
|
went wrong under certain circumstances in UTF-8 mode. This bug could also |
| 727 |
|
have affected the operation of pcre_study(). |
| 728 |
|
|
| 729 |
|
25. Realized that a little bit of performance could be had by replacing |
| 730 |
|
(c & 0xc0) == 0xc0 with c >= 0xc0 when processing UTF-8 characters. |
| 731 |
|
|
| 732 |
|
26. Timing data from pcretest is now shown to 4 decimal places instead of 3. |
| 733 |
|
|
| 734 |
|
27. Possessive quantifiers such as a++ were previously implemented by turning |
| 735 |
|
them into atomic groups such as ($>a+). Now they have their own opcodes, |
| 736 |
|
which improves performance. This includes the automatically created ones |
| 737 |
|
from 23 above. |
| 738 |
|
|
| 739 |
|
28. A pattern such as (?=(\w+))\1: which simulates an atomic group using a |
| 740 |
|
lookahead was broken if it was not anchored. PCRE was mistakenly expecting |
| 741 |
|
the first matched character to be a colon. This applied both to named and |
| 742 |
|
numbered groups. |
| 743 |
|
|
| 744 |
|
29. The ucpinternal.h header file was missing its idempotency #ifdef. |
| 745 |
|
|
| 746 |
|
30. I was sent a "project" file called libpcre.a.dev which I understand makes |
| 747 |
|
building PCRE on Windows easier, so I have included it in the distribution. |
| 748 |
|
|
| 749 |
|
31. There is now a check in pcretest against a ridiculously large number being |
| 750 |
|
returned by pcre_exec() or pcre_dfa_exec(). If this happens in a /g or /G |
| 751 |
|
loop, the loop is abandoned. |
| 752 |
|
|
| 753 |
|
32. Forward references to subpatterns in conditions such as (?(2)...) where |
| 754 |
|
subpattern 2 is defined later cause pcre_compile() to search forwards in |
| 755 |
|
the pattern for the relevant set of parentheses. This search went wrong |
| 756 |
|
when there were unescaped parentheses in a character class, parentheses |
| 757 |
|
escaped with \Q...\E, or parentheses in a #-comment in /x mode. |
| 758 |
|
|
| 759 |
|
33. "Subroutine" calls and backreferences were previously restricted to |
| 760 |
|
referencing subpatterns earlier in the regex. This restriction has now |
| 761 |
|
been removed. |
| 762 |
|
|
| 763 |
|
34. Added a number of extra features that are going to be in Perl 5.10. On the |
| 764 |
|
whole, these are just syntactic alternatives for features that PCRE had |
| 765 |
|
previously implemented using the Python syntax or my own invention. The |
| 766 |
|
other formats are all retained for compatibility. |
| 767 |
|
|
| 768 |
|
(a) Named groups can now be defined as (?<name>...) or (?'name'...) as well |
| 769 |
|
as (?P<name>...). The new forms, as well as being in Perl 5.10, are |
| 770 |
|
also .NET compatible. |
| 771 |
|
|
| 772 |
|
(b) A recursion or subroutine call to a named group can now be defined as |
| 773 |
|
(?&name) as well as (?P>name). |
| 774 |
|
|
| 775 |
|
(c) A backreference to a named group can now be defined as \k<name> or |
| 776 |
|
\k'name' as well as (?P=name). The new forms, as well as being in Perl |
| 777 |
|
5.10, are also .NET compatible. |
| 778 |
|
|
| 779 |
|
(d) A conditional reference to a named group can now use the syntax |
| 780 |
|
(?(<name>) or (?('name') as well as (?(name). |
| 781 |
|
|
| 782 |
|
(e) A "conditional group" of the form (?(DEFINE)...) can be used to define |
| 783 |
|
groups (named and numbered) that are never evaluated inline, but can be |
| 784 |
|
called as "subroutines" from elsewhere. In effect, the DEFINE condition |
| 785 |
|
is always false. There may be only one alternative in such a group. |
| 786 |
|
|
| 787 |
|
(f) A test for recursion can be given as (?(R1).. or (?(R&name)... as well |
| 788 |
|
as the simple (?(R). The condition is true only if the most recent |
| 789 |
|
recursion is that of the given number or name. It does not search out |
| 790 |
|
through the entire recursion stack. |
| 791 |
|
|
| 792 |
|
(g) The escape \gN or \g{N} has been added, where N is a positive or |
| 793 |
|
negative number, specifying an absolute or relative reference. |
| 794 |
|
|
| 795 |
|
35. Tidied to get rid of some further signed/unsigned compiler warnings and |
| 796 |
|
some "unreachable code" warnings. |
| 797 |
|
|
| 798 |
|
36. Updated the Unicode property tables to Unicode version 5.0.0. Amongst other |
| 799 |
|
things, this adds five new scripts. |
| 800 |
|
|
| 801 |
|
37. Perl ignores orphaned \E escapes completely. PCRE now does the same. |
| 802 |
|
There were also incompatibilities regarding the handling of \Q..\E inside |
| 803 |
|
character classes, for example with patterns like [\Qa\E-\Qz\E] where the |
| 804 |
|
hyphen was adjacent to \Q or \E. I hope I've cleared all this up now. |
| 805 |
|
|
| 806 |
|
38. Like Perl, PCRE detects when an indefinitely repeated parenthesized group |
| 807 |
|
matches an empty string, and forcibly breaks the loop. There were bugs in |
| 808 |
|
this code in non-simple cases. For a pattern such as ^(a()*)* matched |
| 809 |
|
against aaaa the result was just "a" rather than "aaaa", for example. Two |
| 810 |
|
separate and independent bugs (that affected different cases) have been |
| 811 |
|
fixed. |
| 812 |
|
|
| 813 |
|
39. Refactored the code to abolish the use of different opcodes for small |
| 814 |
|
capturing bracket numbers. This is a tidy that I avoided doing when I |
| 815 |
|
removed the limit on the number of capturing brackets for 3.5 back in 2001. |
| 816 |
|
The new approach is not only tidier, it makes it possible to reduce the |
| 817 |
|
memory needed to fix the previous bug (38). |
| 818 |
|
|
| 819 |
|
40. Implemented PCRE_NEWLINE_ANY to recognize any of the Unicode newline |
| 820 |
|
sequences (http://unicode.org/unicode/reports/tr18/) as "newline" when |
| 821 |
|
processing dot, circumflex, or dollar metacharacters, or #-comments in /x |
| 822 |
|
mode. |
| 823 |
|
|
| 824 |
|
41. Add \R to match any Unicode newline sequence, as suggested in the Unicode |
| 825 |
|
report. |
| 826 |
|
|
| 827 |
|
42. Applied patch, originally from Ari Pollak, modified by Google, to allow |
| 828 |
|
copy construction and assignment in the C++ wrapper. |
| 829 |
|
|
| 830 |
|
43. Updated pcregrep to support "--newline=any". In the process, I fixed a |
| 831 |
|
couple of bugs that could have given wrong results in the "--newline=crlf" |
| 832 |
|
case. |
| 833 |
|
|
| 834 |
|
44. Added a number of casts and did some reorganization of signed/unsigned int |
| 835 |
|
variables following suggestions from Dair Grant. Also renamed the variable |
| 836 |
|
"this" as "item" because it is a C++ keyword. |
| 837 |
|
|
| 838 |
|
45. Arranged for dftables to add |
| 839 |
|
|
| 840 |
|
#include "pcre_internal.h" |
| 841 |
|
|
| 842 |
|
to pcre_chartables.c because without it, gcc 4.x may remove the array |
| 843 |
|
definition from the final binary if PCRE is built into a static library and |
| 844 |
|
dead code stripping is activated. |
| 845 |
|
|
| 846 |
|
46. For an unanchored pattern, if a match attempt fails at the start of a |
| 847 |
|
newline sequence, and the newline setting is CRLF or ANY, and the next two |
| 848 |
|
characters are CRLF, advance by two characters instead of one. |
| 849 |
|
|
| 850 |
|
|
| 851 |
|
Version 6.7 04-Jul-06 |
| 852 |
|
--------------------- |
| 853 |
|
|
| 854 |
|
1. In order to handle tests when input lines are enormously long, pcretest has |
| 855 |
|
been re-factored so that it automatically extends its buffers when |
| 856 |
|
necessary. The code is crude, but this _is_ just a test program. The |
| 857 |
|
default size has been increased from 32K to 50K. |
| 858 |
|
|
| 859 |
|
2. The code in pcre_study() was using the value of the re argument before |
| 860 |
|
testing it for NULL. (Of course, in any sensible call of the function, it |
| 861 |
|
won't be NULL.) |
| 862 |
|
|
| 863 |
|
3. The memmove() emulation function in pcre_internal.h, which is used on |
| 864 |
|
systems that lack both memmove() and bcopy() - that is, hardly ever - |
| 865 |
|
was missing a "static" storage class specifier. |
| 866 |
|
|
| 867 |
|
4. When UTF-8 mode was not set, PCRE looped when compiling certain patterns |
| 868 |
|
containing an extended class (one that cannot be represented by a bitmap |
| 869 |
|
because it contains high-valued characters or Unicode property items, e.g. |
| 870 |
|
[\pZ]). Almost always one would set UTF-8 mode when processing such a |
| 871 |
|
pattern, but PCRE should not loop if you do not (it no longer does). |
| 872 |
|
[Detail: two cases were found: (a) a repeated subpattern containing an |
| 873 |
|
extended class; (b) a recursive reference to a subpattern that followed a |
| 874 |
|
previous extended class. It wasn't skipping over the extended class |
| 875 |
|
correctly when UTF-8 mode was not set.] |
| 876 |
|
|
| 877 |
|
5. A negated single-character class was not being recognized as fixed-length |
| 878 |
|
in lookbehind assertions such as (?<=[^f]), leading to an incorrect |
| 879 |
|
compile error "lookbehind assertion is not fixed length". |
| 880 |
|
|
| 881 |
|
6. The RunPerlTest auxiliary script was showing an unexpected difference |
| 882 |
|
between PCRE and Perl for UTF-8 tests. It turns out that it is hard to |
| 883 |
|
write a Perl script that can interpret lines of an input file either as |
| 884 |
|
byte characters or as UTF-8, which is what "perltest" was being required to |
| 885 |
|
do for the non-UTF-8 and UTF-8 tests, respectively. Essentially what you |
| 886 |
|
can't do is switch easily at run time between having the "use utf8;" pragma |
| 887 |
|
or not. In the end, I fudged it by using the RunPerlTest script to insert |
| 888 |
|
"use utf8;" explicitly for the UTF-8 tests. |
| 889 |
|
|
| 890 |
|
7. In multiline (/m) mode, PCRE was matching ^ after a terminating newline at |
| 891 |
|
the end of the subject string, contrary to the documentation and to what |
| 892 |
|
Perl does. This was true of both matching functions. Now it matches only at |
| 893 |
|
the start of the subject and immediately after *internal* newlines. |
| 894 |
|
|
| 895 |
|
8. A call of pcre_fullinfo() from pcretest to get the option bits was passing |
| 896 |
|
a pointer to an int instead of a pointer to an unsigned long int. This |
| 897 |
|
caused problems on 64-bit systems. |
| 898 |
|
|
| 899 |
|
9. Applied a patch from the folks at Google to pcrecpp.cc, to fix "another |
| 900 |
|
instance of the 'standard' template library not being so standard". |
| 901 |
|
|
| 902 |
|
10. There was no check on the number of named subpatterns nor the maximum |
| 903 |
|
length of a subpattern name. The product of these values is used to compute |
| 904 |
|
the size of the memory block for a compiled pattern. By supplying a very |
| 905 |
|
long subpattern name and a large number of named subpatterns, the size |
| 906 |
|
computation could be caused to overflow. This is now prevented by limiting |
| 907 |
|
the length of names to 32 characters, and the number of named subpatterns |
| 908 |
|
to 10,000. |
| 909 |
|
|
| 910 |
|
11. Subpatterns that are repeated with specific counts have to be replicated in |
| 911 |
|
the compiled pattern. The size of memory for this was computed from the |
| 912 |
|
length of the subpattern and the repeat count. The latter is limited to |
| 913 |
|
65535, but there was no limit on the former, meaning that integer overflow |
| 914 |
|
could in principle occur. The compiled length of a repeated subpattern is |
| 915 |
|
now limited to 30,000 bytes in order to prevent this. |
| 916 |
|
|
| 917 |
|
12. Added the optional facility to have named substrings with the same name. |
| 918 |
|
|
| 919 |
|
13. Added the ability to use a named substring as a condition, using the |
| 920 |
|
Python syntax: (?(name)yes|no). This overloads (?(R)... and names that |
| 921 |
|
are numbers (not recommended). Forward references are permitted. |
| 922 |
|
|
| 923 |
|
14. Added forward references in named backreferences (if you see what I mean). |
| 924 |
|
|
| 925 |
|
15. In UTF-8 mode, with the PCRE_DOTALL option set, a quantified dot in the |
| 926 |
|
pattern could run off the end of the subject. For example, the pattern |
| 927 |
|
"(?s)(.{1,5})"8 did this with the subject "ab". |
| 928 |
|
|
| 929 |
|
16. If PCRE_DOTALL or PCRE_MULTILINE were set, pcre_dfa_exec() behaved as if |
| 930 |
|
PCRE_CASELESS was set when matching characters that were quantified with ? |
| 931 |
|
or *. |
| 932 |
|
|
| 933 |
|
17. A character class other than a single negated character that had a minimum |
| 934 |
|
but no maximum quantifier - for example [ab]{6,} - was not handled |
| 935 |
|
correctly by pce_dfa_exec(). It would match only one character. |
| 936 |
|
|
| 937 |
|
18. A valid (though odd) pattern that looked like a POSIX character |
| 938 |
|
class but used an invalid character after [ (for example [[,abc,]]) caused |
| 939 |
|
pcre_compile() to give the error "Failed: internal error: code overflow" or |
| 940 |
|
in some cases to crash with a glibc free() error. This could even happen if |
| 941 |
|
the pattern terminated after [[ but there just happened to be a sequence of |
| 942 |
|
letters, a binary zero, and a closing ] in the memory that followed. |
| 943 |
|
|
| 944 |
|
19. Perl's treatment of octal escapes in the range \400 to \777 has changed |
| 945 |
|
over the years. Originally (before any Unicode support), just the bottom 8 |
| 946 |
|
bits were taken. Thus, for example, \500 really meant \100. Nowadays the |
| 947 |
|
output from "man perlunicode" includes this: |
| 948 |
|
|
| 949 |
|
The regular expression compiler produces polymorphic opcodes. That |
| 950 |
|
is, the pattern adapts to the data and automatically switches to |
| 951 |
|
the Unicode character scheme when presented with Unicode data--or |
| 952 |
|
instead uses a traditional byte scheme when presented with byte |
| 953 |
|
data. |
| 954 |
|
|
| 955 |
|
Sadly, a wide octal escape does not cause a switch, and in a string with |
| 956 |
|
no other multibyte characters, these octal escapes are treated as before. |
| 957 |
|
Thus, in Perl, the pattern /\500/ actually matches \100 but the pattern |
| 958 |
|
/\500|\x{1ff}/ matches \500 or \777 because the whole thing is treated as a |
| 959 |
|
Unicode string. |
| 960 |
|
|
| 961 |
|
I have not perpetrated such confusion in PCRE. Up till now, it took just |
| 962 |
|
the bottom 8 bits, as in old Perl. I have now made octal escapes with |
| 963 |
|
values greater than \377 illegal in non-UTF-8 mode. In UTF-8 mode they |
| 964 |
|
translate to the appropriate multibyte character. |
| 965 |
|
|
| 966 |
|
29. Applied some refactoring to reduce the number of warnings from Microsoft |
| 967 |
|
and Borland compilers. This has included removing the fudge introduced |
| 968 |
|
seven years ago for the OS/2 compiler (see 2.02/2 below) because it caused |
| 969 |
|
a warning about an unused variable. |
| 970 |
|
|
| 971 |
|
21. PCRE has not included VT (character 0x0b) in the set of whitespace |
| 972 |
|
characters since release 4.0, because Perl (from release 5.004) does not. |
| 973 |
|
[Or at least, is documented not to: some releases seem to be in conflict |
| 974 |
|
with the documentation.] However, when a pattern was studied with |
| 975 |
|
pcre_study() and all its branches started with \s, PCRE still included VT |
| 976 |
|
as a possible starting character. Of course, this did no harm; it just |
| 977 |
|
caused an unnecessary match attempt. |
| 978 |
|
|
| 979 |
|
22. Removed a now-redundant internal flag bit that recorded the fact that case |
| 980 |
|
dependency changed within the pattern. This was once needed for "required |
| 981 |
|
byte" processing, but is no longer used. This recovers a now-scarce options |
| 982 |
|
bit. Also moved the least significant internal flag bit to the most- |
| 983 |
|
significant bit of the word, which was not previously used (hangover from |
| 984 |
|
the days when it was an int rather than a uint) to free up another bit for |
| 985 |
|
the future. |
| 986 |
|
|
| 987 |
|
23. Added support for CRLF line endings as well as CR and LF. As well as the |
| 988 |
|
default being selectable at build time, it can now be changed at runtime |
| 989 |
|
via the PCRE_NEWLINE_xxx flags. There are now options for pcregrep to |
| 990 |
|
specify that it is scanning data with non-default line endings. |
| 991 |
|
|
| 992 |
|
24. Changed the definition of CXXLINK to make it agree with the definition of |
| 993 |
|
LINK in the Makefile, by replacing LDFLAGS to CXXFLAGS. |
| 994 |
|
|
| 995 |
|
25. Applied Ian Taylor's patches to avoid using another stack frame for tail |
| 996 |
|
recursions. This makes a big different to stack usage for some patterns. |
| 997 |
|
|
| 998 |
|
26. If a subpattern containing a named recursion or subroutine reference such |
| 999 |
|
as (?P>B) was quantified, for example (xxx(?P>B)){3}, the calculation of |
| 1000 |
|
the space required for the compiled pattern went wrong and gave too small a |
| 1001 |
|
value. Depending on the environment, this could lead to "Failed: internal |
| 1002 |
|
error: code overflow at offset 49" or "glibc detected double free or |
| 1003 |
|
corruption" errors. |
| 1004 |
|
|
| 1005 |
|
27. Applied patches from Google (a) to support the new newline modes and (b) to |
| 1006 |
|
advance over multibyte UTF-8 characters in GlobalReplace. |
| 1007 |
|
|
| 1008 |
|
28. Change free() to pcre_free() in pcredemo.c. Apparently this makes a |
| 1009 |
|
difference for some implementation of PCRE in some Windows version. |
| 1010 |
|
|
| 1011 |
|
29. Added some extra testing facilities to pcretest: |
| 1012 |
|
|
| 1013 |
|
\q<number> in a data line sets the "match limit" value |
| 1014 |
|
\Q<number> in a data line sets the "match recursion limt" value |
| 1015 |
|
-S <number> sets the stack size, where <number> is in megabytes |
| 1016 |
|
|
| 1017 |
|
The -S option isn't available for Windows. |
| 1018 |
|
|
| 1019 |
|
|
| 1020 |
|
Version 6.6 06-Feb-06 |
| 1021 |
|
--------------------- |
| 1022 |
|
|
| 1023 |
|
1. Change 16(a) for 6.5 broke things, because PCRE_DATA_SCOPE was not defined |
| 1024 |
|
in pcreposix.h. I have copied the definition from pcre.h. |
| 1025 |
|
|
| 1026 |
|
2. Change 25 for 6.5 broke compilation in a build directory out-of-tree |
| 1027 |
|
because pcre.h is no longer a built file. |
| 1028 |
|
|
| 1029 |
|
3. Added Jeff Friedl's additional debugging patches to pcregrep. These are |
| 1030 |
|
not normally included in the compiled code. |
| 1031 |
|
|
| 1032 |
|
|
| 1033 |
Version 6.5 01-Feb-06 |
Version 6.5 01-Feb-06 |
| 1034 |
--------------------- |
--------------------- |
| 1035 |
|
|