summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authordkf <donal.k.fellows@manchester.ac.uk>2011-03-05 00:35:57 (GMT)
committerdkf <donal.k.fellows@manchester.ac.uk>2011-03-05 00:35:57 (GMT)
commit6f1fd26e91b778b8d1e972e425c2e2593a41f92d (patch)
treedc5e2c9a6260b924b0812e00d961eb79fe9fe786
parent17bf2e2c7ac19e4a2d576a88d3bec1413a02be74 (diff)
parent80a9e493176e81c6becbb1715367300d20208449 (diff)
downloadtcl-6f1fd26e91b778b8d1e972e425c2e2593a41f92d.zip
tcl-6f1fd26e91b778b8d1e972e425c2e2593a41f92d.tar.gz
tcl-6f1fd26e91b778b8d1e972e425c2e2593a41f92d.tar.bz2
[Bug 3185009]: Keep references to resolved object variables so that an unset doesn't leave any dangling pointers for code to trip over.
-rw-r--r--ChangeLog7
-rw-r--r--generic/tclOOMethod.c16
-rw-r--r--tests/oo.test16
3 files changed, 39 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog
index 3976ccd..7274f4e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2011-03-04 Donal K. Fellows <dkf@users.sf.net>
+
+ * generic/tclOOMethod.c (ProcedureMethodCompiledVarConnect)
+ (ProcedureMethodCompiledVarDelete): [Bug 3185009]: Keep references to
+ resolved object variables so that an unset doesn't leave any dangling
+ pointers for code to trip over.
+
2011-03-01 Miguel Sofer <msofer@users.sf.net>
* generic/tclCompCmdsSZ.c (TclCompileThrowCmd)
diff --git a/generic/tclOOMethod.c b/generic/tclOOMethod.c
index 44eb083..4f29337 100644
--- a/generic/tclOOMethod.c
+++ b/generic/tclOOMethod.c
@@ -1055,6 +1055,14 @@ ProcedureMethodCompiledVarConnect(
}
if (cacheIt) {
infoPtr->cachedObjectVar = TclVarHashGetValue(hPtr);
+
+ /*
+ * We must keep a reference to the variable so everything will
+ * continue to work correctly even if it is unset; being unset does
+ * not end the life of the variable at this level. [Bug 3185009]
+ */
+
+ VarHashRefCount(infoPtr->cachedObjectVar)++;
}
return TclVarHashGetValue(hPtr);
}
@@ -1065,6 +1073,14 @@ ProcedureMethodCompiledVarDelete(
{
OOResVarInfo *infoPtr = (OOResVarInfo *) rPtr;
+ /*
+ * Release the reference to the variable if we were holding it.
+ */
+
+ if (infoPtr->cachedObjectVar) {
+ VarHashRefCount(infoPtr->cachedObjectVar)--;
+ TclCleanupVar((Var *) infoPtr->cachedObjectVar, NULL);
+ }
Tcl_DecrRefCount(infoPtr->variableObj);
ckfree((char *) infoPtr);
}
diff --git a/tests/oo.test b/tests/oo.test
index 395e345..60d0077 100644
--- a/tests/oo.test
+++ b/tests/oo.test
@@ -2578,6 +2578,22 @@ test oo-27.12 {variables declaration: leak per instance} -setup {
} -cleanup {
foo destroy
} -result 0
+# This test will actually (normally) crash if it fails!
+test oo-27.13 {variables declaration: Bug 3185009: require refcount management} -setup {
+ oo::object create foo
+} -body {
+ oo::objdefine foo {
+ variable x
+ method set v {set x $v}
+ method unset {} {unset x}
+ method exists {} {info exists x}
+ method get {} {return $x}
+ }
+ list [foo exists] [foo set 7] [foo exists] [foo get] [foo unset] \
+ [foo exists] [catch {foo get} msg] $msg
+} -cleanup {
+ foo destroy
+} -result {0 7 1 7 {} 0 1 {can't read "x": no such variable}}
# A feature that's not supported because the mechanism may change without
# warning, but is supposed to work...