#2990: prevent inconsistent state while updating method cache.

This commit is contained in:
Georg Brandl 2008-05-28 15:41:36 +00:00
parent dee01d8af8
commit 5ec330cb2f
1 changed files with 7 additions and 5 deletions

View File

@ -147,7 +147,7 @@ assign_version_tag(PyTypeObject *type)
cannot be done, 1 if Py_TPFLAGS_VALID_VERSION_TAG.
*/
Py_ssize_t i, n;
PyObject *bases;
PyObject *bases, *tmp;
if (PyType_HasFeature(type, Py_TPFLAGS_VALID_VERSION_TAG))
return 1;
@ -166,9 +166,10 @@ assign_version_tag(PyTypeObject *type)
are borrowed reference */
for (i = 0; i < (1 << MCACHE_SIZE_EXP); i++) {
method_cache[i].value = NULL;
Py_XDECREF(method_cache[i].name);
method_cache[i].name = Py_None;
tmp = method_cache[i].name;
Py_INCREF(Py_None);
method_cache[i].name = Py_None;
Py_XDECREF(tmp);
}
/* mark all version tags as invalid */
PyType_Modified(&PyBaseObject_Type);
@ -2413,7 +2414,7 @@ PyObject *
_PyType_Lookup(PyTypeObject *type, PyObject *name)
{
Py_ssize_t i, n;
PyObject *mro, *res, *base, *dict;
PyObject *mro, *res, *base, *dict, *tmp;
unsigned int h;
if (MCACHE_CACHEABLE_NAME(name) &&
@ -2455,9 +2456,10 @@ _PyType_Lookup(PyTypeObject *type, PyObject *name)
h = MCACHE_HASH_METHOD(type, name);
method_cache[h].version = type->tp_version_tag;
method_cache[h].value = res; /* borrowed */
tmp = method_cache[h].name;
Py_INCREF(name);
Py_DECREF(method_cache[h].name);
method_cache[h].name = name;
Py_DECREF(tmp);
}
return res;
}