diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | generic/tclUtil.c | 16 |
2 files changed, 20 insertions, 2 deletions
@@ -1,3 +1,9 @@ +2010-12-03 Jeff Hobbs <jeffh@ActiveState.com> + + * generic/tclUtil.c (TclReToGlob): add extra check for multiple + inner *s that leads to poor recursive glob matching, defer to + original RE instead. tclbench RE var backtrack. + 2010-12-01 Kevin B. Kenny <kennykb@acm.org> * generic/tclStrToD.c (SetPrecisionLimits, TclDoubleDigits): diff --git a/generic/tclUtil.c b/generic/tclUtil.c index 2a23fd2..ee17166 100644 --- a/generic/tclUtil.c +++ b/generic/tclUtil.c @@ -11,7 +11,7 @@ * See the file "license.terms" for information on usage and redistribution of * this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * RCS: @(#) $Id: tclUtil.c,v 1.97.2.8 2010/11/30 20:59:28 andreas_kupries Exp $ + * RCS: @(#) $Id: tclUtil.c,v 1.97.2.9 2010/12/03 22:27:44 hobbs Exp $ */ #include "tclInt.h" @@ -3326,7 +3326,7 @@ TclReToGlob( Tcl_DString *dsPtr, int *exactPtr) { - int anchorLeft, anchorRight, lastIsStar; + int anchorLeft, anchorRight, lastIsStar, numStars; char *dsStr, *dsStrStart, *msg; const char *p, *strEnd; @@ -3385,6 +3385,7 @@ TclReToGlob( p = reStr; anchorRight = 0; lastIsStar = 0; + numStars = 0; if (*p == '^') { anchorLeft = 1; @@ -3448,6 +3449,7 @@ TclReToGlob( if (!lastIsStar) { *dsStr++ = '*'; lastIsStar = 1; + numStars++; } continue; } else if (p[1] == '+') { @@ -3455,6 +3457,7 @@ TclReToGlob( *dsStr++ = '?'; *dsStr++ = '*'; lastIsStar = 1; + numStars++; continue; } } @@ -3478,6 +3481,15 @@ TclReToGlob( } lastIsStar = 0; } + if (numStars > 1) { + /* + * Heuristic: if >1 non-anchoring *, the risk is large that glob + * matching is slower than the RE engine, so report invalid. + */ + msg = "excessive recursive glob backtrack potential"; + goto invalidGlob; + } + if (!anchorRight && !lastIsStar) { *dsStr++ = '*'; } |