In perl.git, the branch blead has been updated
<http://perl5.git.perl.org/perl.git/commitdiff/b57e41186b2ceb48bef4f0588dcd19e105cc8a38?hp=bfba585ac769bf0862ff2ce15499506aaa370ece>
- Log -----------------------------------------------------------------
commit b57e41186b2ceb48bef4f0588dcd19e105cc8a38
Author: Karl Williamson <pub...@khwilliamson.com>
Date: Tue Jan 18 15:03:41 2011 -0700
regcomp: Disallow multi-char folds in lookbehind
The addition of the ANYOFV regnode to treat multi-char folds in a bracketed
character class has exposed a bug, in which those classes have long been
able
to be varying length (due to the multi-char fold), but the compiler wasn't
aware of it. Now it is, and hence won't allow those which have multi-char
folds to be part of a lookbehind pattern, which requires a constant length.
This patch disallows multi-char folds in a lookbehind bracketed character
class.
-----------------------------------------------------------------------
Summary of changes:
regcomp.c | 24 +++++++++++++++++-------
t/re/pat_advanced.t | 15 ++++++++++++++-
2 files changed, 31 insertions(+), 8 deletions(-)
diff --git a/regcomp.c b/regcomp.c
index 0c34695..729ebfb 100644
--- a/regcomp.c
+++ b/regcomp.c
@@ -138,6 +138,7 @@ typedef struct RExC_state_t {
regnode **recurse; /* Recurse regops */
I32 recurse_count; /* Number of recurse regops */
+ I32 in_lookbehind;
#if ADD_TO_REGEXEC
char *starttry; /* -Dr: where regtry was called. */
#define RExC_starttry (pRExC_state->starttry)
@@ -184,6 +185,7 @@ typedef struct RExC_state_t {
#define RExC_paren_names (pRExC_state->paren_names)
#define RExC_recurse (pRExC_state->recurse)
#define RExC_recurse_count (pRExC_state->recurse_count)
+#define RExC_in_lookbehind (pRExC_state->in_lookbehind)
#define ISMULT1(c) ((c) == '*' || (c) == '+' || (c) == '?')
@@ -4459,6 +4461,7 @@ Perl_re_compile(pTHX_ SV * const pattern, U32
orig_pm_flags)
RExC_sawback = 0;
RExC_seen = 0;
+ RExC_in_lookbehind = 0;
RExC_seen_zerolen = *exp == '^' ? -1 : 0;
RExC_seen_evals = 0;
RExC_extralen = 0;
@@ -5938,6 +5941,7 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32
*flagp,U32 depth)
goto capturing_parens;
}
RExC_seen |= REG_SEEN_LOOKBEHIND;
+ RExC_in_lookbehind++;
RExC_parse++;
case '=': /* (?=...) */
RExC_seen_zerolen++;
@@ -6585,6 +6589,10 @@ S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32
*flagp,U32 depth)
FAIL("Junk on end of regexp"); /* "Can't happen". */
/* NOTREACHED */
}
+
+ if (RExC_in_lookbehind) {
+ RExC_in_lookbehind--;
+ }
if (after_freeze)
RExC_npar = after_freeze;
return(ret);
@@ -8590,9 +8598,6 @@ parseit:
/* The \p could match something in the Latin1 range, hence
* something that isn't utf8 */
ANYOF_FLAGS(ret) |= ANYOF_NONBITMAP;
- if (FOLD) { /* And one of these could have a multi-char fold */
- OP(ret) = ANYOFV;
- }
namedclass = ANYOF_MAX; /* no official name, but it's named */
}
break;
@@ -8921,8 +8926,10 @@ parseit:
/* Currently, we don't look at every value in the range.
* Therefore we have to assume the worst case: that if
- * folding, it will match more than one character */
- if (FOLD) {
+ * folding, it will match more than one character. But in
+ * lookbehind patterns, can only be single character
+ * length, so disallow those folds */
+ if (FOLD && ! RExC_in_lookbehind) {
OP(ret) = ANYOFV;
}
}
@@ -8956,8 +8963,9 @@ parseit:
#endif
Perl_sv_catpvf(aTHX_ listsv,
"%04"UVxf"\n", f);
- else {
+ else if (! RExC_in_lookbehind) {
/* Any multicharacter foldings
+ * (disallowed in lookbehind patterns)
* require the following transform:
* [ABCDEF] -> (?:[ABCabcDEFd]|pq|rst)
* where E folds into "pq" and F folds
@@ -9032,8 +9040,10 @@ parseit:
/* This is the one character in the bitmap that needs special handling
* under non-locale folding, as it folds to two characters 'ss'. This
* happens if it is set and not inverting, or isn't set and are
- * inverting */
+ * inverting (disallowed in lookbehind patterns because they can't be
+ * variable length) */
if (! LOC
+ && ! RExC_in_lookbehind
&& (cBOOL(ANYOF_BITMAP_TEST(ret, LATIN_SMALL_LETTER_SHARP_S))
^ cBOOL(ANYOF_FLAGS(ret) & ANYOF_INVERT)))
{
diff --git a/t/re/pat_advanced.t b/t/re/pat_advanced.t
index 0254813..de48ad4 100644
--- a/t/re/pat_advanced.t
+++ b/t/re/pat_advanced.t
@@ -21,7 +21,7 @@ BEGIN {
}
-plan tests => 1303; # Update this when adding/deleting tests.
+plan tests => 1304; # Update this when adding/deleting tests.
run_tests() unless caller;
@@ -2072,6 +2072,16 @@ sub run_tests {
}
}
+ { # Bleadperl v5.13.8-292-gf56b639 breaks NEZUMI/Unicode-LineBreak-1.011
+ # \xdf in lookbehind failed to compile as is multi-char fold
+ eval_ok 'qr{
+ (?u: (?<=^url:) |
+ (?<=[/]) (?=[^/]) |
+ (?<=[^-.]) (?=[-~.,_?\#%=&]) |
+ (?<=[=&]) (?=.)
+ )}iox', "Lookbehind with \\xdf matchable compiles";
+ }
+
#
# Keep the following tests last -- they may crash perl
#
@@ -2106,6 +2116,9 @@ sub run_tests {
eval $a =~ /[a-z]/;
ok(1); # If it didn't crash, it worked.
}
+
+ # !!! NOTE that tests that aren't at all likely to crash perl should go
+ # a ways above, above these last ones.
} # End of sub run_tests
1;
--
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