Fixes and enhancements to _elementtree:
* Fixed refleak problems when GC collection is run (see messages in
issue #14065)
* Added weakref support to Element objects
diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c
index a9da3ec..5425269 100644
--- a/Modules/_elementtree.c
+++ b/Modules/_elementtree.c
@@ -48,6 +48,7 @@
/* See http://www.python.org/psf/license for licensing details. */
#include "Python.h"
+#include "structmember.h"
#define VERSION "1.0.6"
@@ -229,6 +230,8 @@
ElementObjectExtra* extra;
+ PyObject *weakreflist; /* For tp_weaklistoffset */
+
} ElementObject;
static PyTypeObject Element_Type;
@@ -261,17 +264,24 @@
LOCAL(void)
dealloc_extra(ElementObject* self)
{
+ if (!self->extra)
+ return;
+
+ /* Avoid DECREFs calling into this code again (cycles, etc.)
+ */
+ ElementObjectExtra *myextra = self->extra;
+ self->extra = NULL;
+
+ Py_DECREF(myextra->attrib);
+
int i;
+ for (i = 0; i < myextra->length; i++)
+ Py_DECREF(myextra->children[i]);
- Py_DECREF(self->extra->attrib);
+ if (myextra->children != myextra->_children)
+ PyObject_Free(myextra->children);
- for (i = 0; i < self->extra->length; i++)
- Py_DECREF(self->extra->children[i]);
-
- if (self->extra->children != self->extra->_children)
- PyObject_Free(self->extra->children);
-
- PyObject_Free(self->extra);
+ PyObject_Free(myextra);
}
/* Convenience internal function to create new Element objects with the given
@@ -308,6 +318,8 @@
Py_INCREF(Py_None);
self->tail = Py_None;
+ self->weakreflist = NULL;
+
ALLOC(sizeof(ElementObject), "create element");
PyObject_GC_Track(self);
return (PyObject*) self;
@@ -328,6 +340,7 @@
e->tail = Py_None;
e->extra = NULL;
+ e->weakreflist = NULL;
}
return (PyObject *)e;
}
@@ -576,19 +589,28 @@
static int
element_gc_clear(ElementObject *self)
{
- PyObject *text = JOIN_OBJ(self->text);
- PyObject *tail = JOIN_OBJ(self->tail);
Py_CLEAR(self->tag);
- Py_CLEAR(text);
- Py_CLEAR(tail);
+
+ /* The following is like Py_CLEAR for self->text and self->tail, but
+ * written explicitily because the real pointers hide behind access
+ * macros.
+ */
+ if (self->text) {
+ PyObject *tmp = JOIN_OBJ(self->text);
+ self->text = NULL;
+ Py_DECREF(tmp);
+ }
+
+ if (self->tail) {
+ PyObject *tmp = JOIN_OBJ(self->tail);
+ self->tail = NULL;
+ Py_DECREF(tmp);
+ }
/* After dropping all references from extra, it's no longer valid anyway,
- ** so fully deallocate it (see also element_clearmethod)
+ * so fully deallocate it.
*/
- if (self->extra) {
- dealloc_extra(self);
- self->extra = NULL;
- }
+ dealloc_extra(self);
return 0;
}
@@ -596,6 +618,10 @@
element_dealloc(ElementObject* self)
{
PyObject_GC_UnTrack(self);
+
+ if (self->weakreflist != NULL)
+ PyObject_ClearWeakRefs((PyObject *) self);
+
/* element_gc_clear clears all references and deallocates extra
*/
element_gc_clear(self);
@@ -626,10 +652,7 @@
if (!PyArg_ParseTuple(args, ":clear"))
return NULL;
- if (self->extra) {
- dealloc_extra(self);
- self->extra = NULL;
- }
+ dealloc_extra(self);
Py_INCREF(Py_None);
Py_DECREF(JOIN_OBJ(self->text));
@@ -1693,7 +1716,7 @@
(traverseproc)element_gc_traverse, /* tp_traverse */
(inquiry)element_gc_clear, /* tp_clear */
0, /* tp_richcompare */
- 0, /* tp_weaklistoffset */
+ offsetof(ElementObject, weakreflist), /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
element_methods, /* tp_methods */