Revision: 1352
http://vcs.pcre.org/viewvc?view=rev&revision=1352
Author: ph10
Date: 2013-07-29 16:49:21 +0100 (Mon, 29 Jul 2013)
Log Message:
-----------
Fix incorrect "first data item" recorded for an assertion condition.
Modified Paths:
--------------
code/trunk/ChangeLog
code/trunk/pcre_compile.c
code/trunk/testdata/testinput1
code/trunk/testdata/testinput2
code/trunk/testdata/testoutput1
code/trunk/testdata/testoutput12
code/trunk/testdata/testoutput2
Modified: code/trunk/ChangeLog
===================================================================
--- code/trunk/ChangeLog 2013-07-27 11:18:33 UTC (rev 1351)
+++ code/trunk/ChangeLog 2013-07-29 15:49:21 UTC (rev 1352)
@@ -51,6 +51,12 @@
there was no match, the code could incorrectly back up beyond the match
point, and potentially beyond the first character in the subject,
leading to a segfault or an incorrect match result.
+
+10. A conditional group with an assertion condition could lead to PCRE
+ recording an incorrect first data item for a match if no other firse data
+ item was recorded. For example, the pattern (?(?=ab)ab) recorded "a" as a
+ first data item, and therefore matched "ca" after "c" instead of at the
+ start.
Version 8.33 28-May-2013
Modified: code/trunk/pcre_compile.c
===================================================================
--- code/trunk/pcre_compile.c 2013-07-27 11:18:33 UTC (rev 1351)
+++ code/trunk/pcre_compile.c 2013-07-29 15:49:21 UTC (rev 1352)
@@ -2361,7 +2361,7 @@
typedef struct recurse_check {
struct recurse_check *prev;
const pcre_uchar *group;
-} recurse_check;
+} recurse_check;
static BOOL
could_be_empty_branch(const pcre_uchar *code, const pcre_uchar *endcode,
@@ -2377,7 +2377,7 @@
const pcre_uchar *ccode;
c = *code;
-
+
/* Skip over forward assertions; the other assertions are skipped by
first_significant_code() with a TRUE final argument. */
@@ -2405,27 +2405,27 @@
NULL. */
if (cd->start_workspace != NULL)
- {
- const pcre_uchar *tcode;
+ {
+ const pcre_uchar *tcode;
for (tcode = cd->start_workspace; tcode < cd->hwm; tcode += LINK_SIZE)
if ((int)GET(tcode, 0) == (int)(code + 1 - cd->start_code)) return TRUE;
if (GET(scode, 1) == 0) return TRUE; /* Unclosed */
}
-
- /* If we are scanning a completed pattern, there are no forward references
- and all groups are complete. We need to detect whether this is a recursive
+
+ /* If we are scanning a completed pattern, there are no forward references
+ and all groups are complete. We need to detect whether this is a recursive
call, as otherwise there will be an infinite loop. If it is a recursion,
- just skip over it. Simple recursions are easily detected. For mutual
- recursions we keep a chain on the stack. */
-
+ just skip over it. Simple recursions are easily detected. For mutual
+ recursions we keep a chain on the stack. */
+
else
- {
+ {
recurse_check *r = recurses;
const pcre_uchar *endgroup = scode;
-
+
do endgroup += GET(endgroup, 1); while (*endgroup == OP_ALT);
if (code >= scode && code <= endgroup) continue; /* Simple recursion */
-
+
for (r = recurses; r != NULL; r = r->prev)
if (r->group == scode) break;
if (r != NULL) continue; /* Mutual recursion */
@@ -2436,8 +2436,8 @@
empty_branch = FALSE;
this_recurse.prev = recurses;
- this_recurse.group = scode;
-
+ this_recurse.group = scode;
+
do
{
if (could_be_empty_branch(scode, endcode, utf, cd, &this_recurse))
@@ -2557,29 +2557,29 @@
case OP_ANY:
case OP_ALLANY:
case OP_ANYBYTE:
-
+
case OP_PROP:
case OP_NOTPROP:
case OP_ANYNL:
-
+
case OP_NOT_HSPACE:
case OP_HSPACE:
case OP_NOT_VSPACE:
- case OP_VSPACE:
+ case OP_VSPACE:
case OP_EXTUNI:
-
+
case OP_NOT_DIGIT:
case OP_DIGIT:
case OP_NOT_WHITESPACE:
case OP_WHITESPACE:
case OP_NOT_WORDCHAR:
case OP_WORDCHAR:
-
+
case OP_CHAR:
case OP_CHARI:
case OP_NOT:
case OP_NOTI:
-
+
case OP_PLUS:
case OP_PLUSI:
case OP_MINPLUS:
@@ -2589,22 +2589,22 @@
case OP_NOTPLUSI:
case OP_NOTMINPLUS:
case OP_NOTMINPLUSI:
-
+
case OP_POSPLUS:
case OP_POSPLUSI:
case OP_NOTPOSPLUS:
case OP_NOTPOSPLUSI:
-
+
case OP_EXACT:
case OP_EXACTI:
case OP_NOTEXACT:
- case OP_NOTEXACTI:
-
+ case OP_NOTEXACTI:
+
case OP_TYPEPLUS:
case OP_TYPEMINPLUS:
case OP_TYPEPOSPLUS:
case OP_TYPEEXACT:
-
+
return FALSE;
/* These are going to continue, as they may be empty, but we have to
@@ -2644,52 +2644,52 @@
#if defined SUPPORT_UTF && !defined COMPILE_PCRE32
case OP_STAR:
case OP_STARI:
- case OP_NOTSTAR:
- case OP_NOTSTARI:
-
+ case OP_NOTSTAR:
+ case OP_NOTSTARI:
+
case OP_MINSTAR:
case OP_MINSTARI:
- case OP_NOTMINSTAR:
+ case OP_NOTMINSTAR:
case OP_NOTMINSTARI:
-
+
case OP_POSSTAR:
case OP_POSSTARI:
- case OP_NOTPOSSTAR:
+ case OP_NOTPOSSTAR:
case OP_NOTPOSSTARI:
-
+
case OP_QUERY:
case OP_QUERYI:
- case OP_NOTQUERY:
- case OP_NOTQUERYI:
-
+ case OP_NOTQUERY:
+ case OP_NOTQUERYI:
+
case OP_MINQUERY:
case OP_MINQUERYI:
case OP_NOTMINQUERY:
case OP_NOTMINQUERYI:
-
+
case OP_POSQUERY:
case OP_POSQUERYI:
case OP_NOTPOSQUERY:
case OP_NOTPOSQUERYI:
-
+
if (utf && HAS_EXTRALEN(code[1])) code += GET_EXTRALEN(code[1]);
break;
case OP_UPTO:
case OP_UPTOI:
- case OP_NOTUPTO:
- case OP_NOTUPTOI:
-
+ case OP_NOTUPTO:
+ case OP_NOTUPTOI:
+
case OP_MINUPTO:
case OP_MINUPTOI:
- case OP_NOTMINUPTO:
+ case OP_NOTMINUPTO:
case OP_NOTMINUPTOI:
-
+
case OP_POSUPTO:
case OP_POSUPTOI:
- case OP_NOTPOSUPTO:
+ case OP_NOTPOSUPTO:
case OP_NOTPOSUPTOI:
-
+
if (utf && HAS_EXTRALEN(code[1 + IMM2_SIZE])) code += GET_EXTRALEN(code[1 + IMM2_SIZE]);
break;
#endif
@@ -3754,22 +3754,22 @@
phase. The value of lengthptr distinguishes the two phases.
Arguments:
- optionsptr pointer to the option bits
- codeptr points to the pointer to the current code point
- ptrptr points to the current pattern pointer
- errorcodeptr points to error code variable
- firstcharptr place to put the first required character
+ optionsptr pointer to the option bits
+ codeptr points to the pointer to the current code point
+ ptrptr points to the current pattern pointer
+ errorcodeptr points to error code variable
+ firstcharptr place to put the first required character
firstcharflagsptr place to put the first character flags, or a negative number
- reqcharptr place to put the last required character
- reqcharflagsptr place to put the last required character flags, or a negative number
- bcptr points to current branch chain
- cond_depth conditional nesting depth
- cd contains pointers to tables etc.
- lengthptr NULL during the real compile phase
- points to length accumulator during pre-compile phase
+ reqcharptr place to put the last required character
+ reqcharflagsptr place to put the last required character flags, or a negative number
+ bcptr points to current branch chain
+ cond_depth conditional nesting depth
+ cd contains pointers to tables etc.
+ lengthptr NULL during the real compile phase
+ points to length accumulator during pre-compile phase
-Returns: TRUE on success
- FALSE, with *errorcodeptr set non-zero on error
+Returns: TRUE on success
+ FALSE, with *errorcodeptr set non-zero on error
*/
static BOOL
@@ -7058,7 +7058,8 @@
*code++ = OP_PROP;
*code++ = PT_CLIST;
*code++ = c;
- if (firstcharflags == REQ_UNSET) firstcharflags = zerofirstcharflags = REQ_NONE;
+ if (firstcharflags == REQ_UNSET)
+ firstcharflags = zerofirstcharflags = REQ_NONE;
break;
}
}
@@ -7147,24 +7148,24 @@
value of lengthptr distinguishes the two phases.
Arguments:
- options option bits, including any changes for this subpattern
- codeptr -> the address of the current code pointer
- ptrptr -> the address of the current pattern pointer
- errorcodeptr -> pointer to error code variable
- lookbehind TRUE if this is a lookbehind assertion
- reset_bracount TRUE to reset the count for each branch
- skipbytes skip this many bytes at start (for brackets and OP_COND)
- cond_depth depth of nesting for conditional subpatterns
- firstcharptr place to put the first required character
+ options option bits, including any changes for this subpattern
+ codeptr -> the address of the current code pointer
+ ptrptr -> the address of the current pattern pointer
+ errorcodeptr -> pointer to error code variable
+ lookbehind TRUE if this is a lookbehind assertion
+ reset_bracount TRUE to reset the count for each branch
+ skipbytes skip this many bytes at start (for brackets and OP_COND)
+ cond_depth depth of nesting for conditional subpatterns
+ firstcharptr place to put the first required character
firstcharflagsptr place to put the first character flags, or a negative number
- reqcharptr place to put the last required character
- reqcharflagsptr place to put the last required character flags, or a negative number
- bcptr pointer to the chain of currently open branches
- cd points to the data block with tables pointers etc.
- lengthptr NULL during the real compile phase
- points to length accumulator during pre-compile phase
+ reqcharptr place to put the last required character
+ reqcharflagsptr place to put the last required character flags, or a negative number
+ bcptr pointer to the chain of currently open branches
+ cd points to the data block with tables pointers etc.
+ lengthptr NULL during the real compile phase
+ points to length accumulator during pre-compile phase
-Returns: TRUE on success
+Returns: TRUE on success
*/
static BOOL
@@ -7701,13 +7702,14 @@
discarded, because they can cause conflicts with actual literals that follow.
However, if we end up without a first char setting for an unanchored pattern,
it is worth scanning the regex to see if there is an initial asserted first
-char. If all branches start with the same asserted char, or with a bracket all
-of whose alternatives start with the same asserted char (recurse ad lib), then
-we return that char, otherwise -1.
+char. If all branches start with the same asserted char, or with a
+non-conditional bracket all of whose alternatives start with the same asserted
+char (recurse ad lib), then we return that char, with the flags set to zero or
+REQ_CASELESS; otherwise return zero with REQ_NONE in the flags.
Arguments:
code points to start of expression (the bracket)
- flags points to the first char flags, or to REQ_NONE
+ flags points to the first char flags, or to REQ_NONE
inassert TRUE if in an assertion
Returns: the fixed first char, or 0 with REQ_NONE in flags
@@ -7744,7 +7746,6 @@
case OP_ASSERT:
case OP_ONCE:
case OP_ONCE_NC:
- case OP_COND:
d = find_firstassertedchar(scode, &dflags, op == OP_ASSERT);
if (dflags < 0)
return 0;
@@ -8297,12 +8298,12 @@
}
}
-/* If the workspace had to be expanded, free the new memory. Set the pointer to
+/* If the workspace had to be expanded, free the new memory. Set the pointer to
NULL to indicate that forward references have been filled in. */
if (cd->workspace_size > COMPILE_WORK_SIZE)
(PUBL(free))((void *)cd->start_workspace);
-cd->start_workspace = NULL;
+cd->start_workspace = NULL;
/* Give an error if there's back reference to a non-existent capturing
subpattern. */
@@ -8506,7 +8507,7 @@
}
#endif /* PCRE_DEBUG */
-/* Check for a pattern than can match an empty string, so that this information
+/* Check for a pattern than can match an empty string, so that this information
can be provided to applications. */
do
@@ -8515,7 +8516,7 @@
{
re->flags |= PCRE_MATCH_EMPTY;
break;
- }
+ }
codestart += GET(codestart, 1);
}
while (*codestart == OP_ALT);
Modified: code/trunk/testdata/testinput1
===================================================================
--- code/trunk/testdata/testinput1 2013-07-27 11:18:33 UTC (rev 1351)
+++ code/trunk/testdata/testinput1 2013-07-29 15:49:21 UTC (rev 1352)
@@ -1,6 +1,6 @@
/-- This set of tests is for features that are compatible with all versions of
- Perl >= 5.10, in non-UTF-8 mode. It should run clean for both the 8-bit and
- 16-bit PCRE libraries. --/
+ Perl >= 5.10, in non-UTF-8 mode. It should run clean for the 8-bit, 16-bit,
+ and 32-bit PCRE libraries. --/
/the quick brown fox/
the quick brown fox
@@ -4221,9 +4221,6 @@
ab
bc
-/^(?=(a)){0}b(?1)/
- backgammon
-
/^(?=(?1))?[az]([abc])d/
abd
zcdxx
@@ -5608,4 +5605,8 @@
aaaa
aaa
+/(?(?=ab)ab)/+
+ ca
+ cd
+
/-- End of testinput1 --/
Modified: code/trunk/testdata/testinput2
===================================================================
--- code/trunk/testdata/testinput2 2013-07-27 11:18:33 UTC (rev 1351)
+++ code/trunk/testdata/testinput2 2013-07-29 15:49:21 UTC (rev 1352)
@@ -3837,4 +3837,9 @@
aaaaaaaaaaaaaz
aaaaaaaaaaaaaz\Q10
+/-- This test causes a segfault with Perl 5.18.0 --/
+
+/^(?=(a)){0}b(?1)/
+ backgammon
+
/-- End of testinput2 --/
Modified: code/trunk/testdata/testoutput1
===================================================================
--- code/trunk/testdata/testoutput1 2013-07-27 11:18:33 UTC (rev 1351)
+++ code/trunk/testdata/testoutput1 2013-07-29 15:49:21 UTC (rev 1352)
@@ -1,6 +1,6 @@
/-- This set of tests is for features that are compatible with all versions of
- Perl >= 5.10, in non-UTF-8 mode. It should run clean for both the 8-bit and
- 16-bit PCRE libraries. --/
+ Perl >= 5.10, in non-UTF-8 mode. It should run clean for the 8-bit, 16-bit,
+ and 32-bit PCRE libraries. --/
/the quick brown fox/
the quick brown fox
@@ -6904,10 +6904,6 @@
bc
0: b
-/^(?=(a)){0}b(?1)/
- backgammon
- 0: ba
-
/^(?=(?1))?[az]([abc])d/
abd
0: abd
@@ -9200,4 +9196,12 @@
aaa
No match
+/(?(?=ab)ab)/+
+ ca
+ 0:
+ 0+ ca
+ cd
+ 0:
+ 0+ cd
+
/-- End of testinput1 --/
Modified: code/trunk/testdata/testoutput12
===================================================================
--- code/trunk/testdata/testoutput12 2013-07-27 11:18:33 UTC (rev 1351)
+++ code/trunk/testdata/testoutput12 2013-07-29 15:49:21 UTC (rev 1352)
@@ -15,7 +15,7 @@
Capturing subpattern count = 0
May match empty string
No options
-First char = 'a'
+No first char
No need char
Study returned NULL
JIT study was not successful
@@ -24,7 +24,7 @@
Capturing subpattern count = 0
May match empty string
No options
-First char = 'a'
+No first char
No need char
Subject length lower bound = -1
No set of starting bytes
Modified: code/trunk/testdata/testoutput2
===================================================================
--- code/trunk/testdata/testoutput2 2013-07-27 11:18:33 UTC (rev 1351)
+++ code/trunk/testdata/testoutput2 2013-07-29 15:49:21 UTC (rev 1352)
@@ -12718,4 +12718,10 @@
aaaaaaaaaaaaaz\Q10
Error -21 (recursion limit exceeded)
+/-- This test causes a segfault with Perl 5.18.0 --/
+
+/^(?=(a)){0}b(?1)/
+ backgammon
+ 0: ba
+
/-- End of testinput2 --/
