[Python-checkins] cpython (2.7): Issue #20437: Fixed 43 potential bugs when deleting objects references.

serhiy.storchaka python-checkins at python.org
Sun Feb 9 12:56:22 CET 2014

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http://hg.python.org/cpython/rev/6b10943a5916
changeset: 89084:6b10943a5916
branch: 2.7
parent: 89067:d579866d6419
user: Serhiy Storchaka <storchaka at gmail.com>
date: Sun Feb 09 13:14:04 2014 +0200
summary:
 Issue #20437: Fixed 43 potential bugs when deleting objects references.
files:
 Mac/Modules/carbonevt/_CarbonEvtmodule.c | 3 +-
 Mac/Modules/list/_Listmodule.c | 3 +-
 Misc/NEWS | 2 +
 Modules/_bsddb.c | 21 ++++--------
 Modules/_ctypes/_ctypes.c | 18 +++------
 Modules/_elementtree.c | 8 ++--
 Modules/_sqlite/connection.c | 3 +-
 Modules/_sqlite/cursor.c | 9 +---
 Modules/cPickle.c | 3 +-
 Modules/cdmodule.c | 18 +++------
 Modules/flmodule.c | 12 ++----
 Modules/readline.c | 3 +-
 Modules/selectmodule.c | 3 +-
 Modules/svmodule.c | 3 +-
 Objects/tupleobject.c | 6 +--
 Objects/unicodeobject.c | 6 +--
 Python/ceval.c | 3 +-
 Python/sysmodule.c | 3 +-
 18 files changed, 45 insertions(+), 82 deletions(-)
diff --git a/Mac/Modules/carbonevt/_CarbonEvtmodule.c b/Mac/Modules/carbonevt/_CarbonEvtmodule.c
--- a/Mac/Modules/carbonevt/_CarbonEvtmodule.c
+++ b/Mac/Modules/carbonevt/_CarbonEvtmodule.c
@@ -1051,8 +1051,7 @@
 _err = RemoveEventHandler(_self->ob_itself);
 if (_err != noErr) return PyMac_Error(_err);
 _self->ob_itself = NULL;
- Py_DECREF(_self->ob_callback);
- _self->ob_callback = NULL;
+ Py_CLEAR(_self->ob_callback);
 Py_INCREF(Py_None);
 _res = Py_None;
 return _res;
diff --git a/Mac/Modules/list/_Listmodule.c b/Mac/Modules/list/_Listmodule.c
--- a/Mac/Modules/list/_Listmodule.c
+++ b/Mac/Modules/list/_Listmodule.c
@@ -76,8 +76,7 @@
 
 static void ListObj_dealloc(ListObject *self)
 {
- Py_XDECREF(self->ob_ldef_func);
- self->ob_ldef_func = NULL;
+ Py_CLEAR(self->ob_ldef_func);
 SetListRefCon(self->ob_itself, (long)0);
 if (self->ob_must_be_disposed && self->ob_itself) LDispose(self->ob_itself);
 self->ob_type->tp_free((PyObject *)self);
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -9,6 +9,8 @@
 Core and Builtins
 -----------------
 
+- Issue #20437: Fixed 43 potential bugs when deleting objects references.
+
 - Issue #20494: Ensure that free()d memory arenas are really released on POSIX
 systems supporting anonymous memory mappings. Patch by Charles-François
 Natali.
diff --git a/Modules/_bsddb.c b/Modules/_bsddb.c
--- a/Modules/_bsddb.c
+++ b/Modules/_bsddb.c
@@ -949,8 +949,7 @@
 * DBTxns and closing any open DBs first. */
 if (makeDBError(err)) {
 if (self->myenvobj) {
- Py_DECREF(self->myenvobj);
- self->myenvobj = NULL;
+ Py_CLEAR(self->myenvobj);
 }
 Py_DECREF(self);
 self = NULL;
@@ -982,20 +981,16 @@
 PyObject_ClearWeakRefs((PyObject *) self);
 }
 if (self->myenvobj) {
- Py_DECREF(self->myenvobj);
- self->myenvobj = NULL;
+ Py_CLEAR(self->myenvobj);
 }
 if (self->associateCallback != NULL) {
- Py_DECREF(self->associateCallback);
- self->associateCallback = NULL;
+ Py_CLEAR(self->associateCallback);
 }
 if (self->btCompareCallback != NULL) {
- Py_DECREF(self->btCompareCallback);
- self->btCompareCallback = NULL;
+ Py_CLEAR(self->btCompareCallback);
 }
 if (self->dupCompareCallback != NULL) {
- Py_DECREF(self->dupCompareCallback);
- self->dupCompareCallback = NULL;
+ Py_CLEAR(self->dupCompareCallback);
 }
 Py_DECREF(self->private_obj);
 PyObject_Del(self);
@@ -1160,8 +1155,7 @@
 PyErr_Clear();
 }
 
- Py_XDECREF(self->event_notifyCallback);
- self->event_notifyCallback = NULL;
+ Py_CLEAR(self->event_notifyCallback);
 
 if (self->in_weakreflist != NULL) {
 PyObject_ClearWeakRefs((PyObject *) self);
@@ -1640,8 +1634,7 @@
 MYDB_END_ALLOW_THREADS;
 
 if (err) {
- Py_XDECREF(secondaryDB->associateCallback);
- secondaryDB->associateCallback = NULL;
+ Py_CLEAR(secondaryDB->associateCallback);
 secondaryDB->primaryDBType = 0;
 }
 
diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -194,10 +194,8 @@
 if (-1 == PyDict_DelItem(self->dict, self->key))
 /* XXX Error context */
 PyErr_WriteUnraisable(Py_None);
- Py_DECREF(self->key);
- self->key = NULL;
- Py_DECREF(self->dict);
- self->dict = NULL;
+ Py_CLEAR(self->key);
+ Py_CLEAR(self->dict);
 }
 Py_INCREF(Py_None);
 return Py_None;
@@ -3040,10 +3038,8 @@
 PyCFuncPtr_set_restype(PyCFuncPtrObject *self, PyObject *ob)
 {
 if (ob == NULL) {
- Py_XDECREF(self->restype);
- self->restype = NULL;
- Py_XDECREF(self->checker);
- self->checker = NULL;
+ Py_CLEAR(self->restype);
+ Py_CLEAR(self->checker);
 return 0;
 }
 if (ob != Py_None && !PyType_stgdict(ob) && !PyCallable_Check(ob)) {
@@ -3086,10 +3082,8 @@
 PyObject *converters;
 
 if (ob == NULL || ob == Py_None) {
- Py_XDECREF(self->converters);
- self->converters = NULL;
- Py_XDECREF(self->argtypes);
- self->argtypes = NULL;
+ Py_CLEAR(self->converters);
+ Py_CLEAR(self->argtypes);
 } else {
 converters = converters_from_argtypes(ob);
 if (!converters)
diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c
--- a/Modules/_elementtree.c
+++ b/Modules/_elementtree.c
@@ -2739,10 +2739,10 @@
 target->events = events;
 
 /* clear out existing events */
- Py_XDECREF(target->start_event_obj); target->start_event_obj = NULL;
- Py_XDECREF(target->end_event_obj); target->end_event_obj = NULL;
- Py_XDECREF(target->start_ns_event_obj); target->start_ns_event_obj = NULL;
- Py_XDECREF(target->end_ns_event_obj); target->end_ns_event_obj = NULL;
+ Py_CLEAR(target->start_event_obj);
+ Py_CLEAR(target->end_event_obj);
+ Py_CLEAR(target->start_ns_event_obj);
+ Py_CLEAR(target->end_ns_event_obj);
 
 if (event_set == Py_None) {
 /* default is "end" only */
diff --git a/Modules/_sqlite/connection.c b/Modules/_sqlite/connection.c
--- a/Modules/_sqlite/connection.c
+++ b/Modules/_sqlite/connection.c
@@ -369,8 +369,7 @@
 if (self->apsw_connection) {
 ret = PyObject_CallMethod(self->apsw_connection, "close", "");
 Py_XDECREF(ret);
- Py_XDECREF(self->apsw_connection);
- self->apsw_connection = NULL;
+ Py_CLEAR(self->apsw_connection);
 self->db = NULL;
 } else {
 Py_BEGIN_ALLOW_THREADS
diff --git a/Modules/_sqlite/cursor.c b/Modules/_sqlite/cursor.c
--- a/Modules/_sqlite/cursor.c
+++ b/Modules/_sqlite/cursor.c
@@ -231,8 +231,7 @@
 if (converter != Py_None) {
 Py_DECREF(converter);
 }
- Py_XDECREF(self->row_cast_map);
- self->row_cast_map = NULL;
+ Py_CLEAR(self->row_cast_map);
 
 return -1;
 }
@@ -468,8 +467,7 @@
 allow_8bit_chars = ((self->connection->text_factory != (PyObject*)&PyUnicode_Type) &&
 (self->connection->text_factory != pysqlite_OptimizedUnicode));
 
- Py_XDECREF(self->next_row);
- self->next_row = NULL;
+ Py_CLEAR(self->next_row);
 
 if (multiple) {
 /* executemany() */
@@ -896,8 +894,7 @@
 if (!self->next_row) {
 if (self->statement) {
 (void)pysqlite_statement_reset(self->statement);
- Py_DECREF(self->statement);
- self->statement = NULL;
+ Py_CLEAR(self->statement);
 }
 return NULL;
 }
diff --git a/Modules/cPickle.c b/Modules/cPickle.c
--- a/Modules/cPickle.c
+++ b/Modules/cPickle.c
@@ -324,8 +324,7 @@
 
 #define FREE_ARG_TUP(self) { \
 if (Py_REFCNT(self->arg) > 1) { \
- Py_DECREF(self->arg); \
- self->arg=NULL; \
+ Py_CLEAR(self->arg); \
 } \
 }
 
diff --git a/Modules/cdmodule.c b/Modules/cdmodule.c
--- a/Modules/cdmodule.c
+++ b/Modules/cdmodule.c
@@ -535,10 +535,8 @@
 
 /* no sense in keeping the callbacks, so remove them */
 for (i = 0; i < NCALLBACKS; i++) {
- Py_XDECREF(self->ob_cdcallbacks[i].ob_cdcallback);
- self->ob_cdcallbacks[i].ob_cdcallback = NULL;
- Py_XDECREF(self->ob_cdcallbacks[i].ob_cdcallbackarg);
- self->ob_cdcallbacks[i].ob_cdcallbackarg = NULL;
+ Py_CLEAR(self->ob_cdcallbacks[i].ob_cdcallback);
+ Py_CLEAR(self->ob_cdcallbacks[i].ob_cdcallbackarg);
 }
 
 Py_INCREF(Py_None);
@@ -588,11 +586,9 @@
 
 CDremovecallback(self->ob_cdparser, (CDDATATYPES) type);
 
- Py_XDECREF(self->ob_cdcallbacks[type].ob_cdcallback);
- self->ob_cdcallbacks[type].ob_cdcallback = NULL;
+ Py_CLEAR(self->ob_cdcallbacks[type].ob_cdcallback);
 
- Py_XDECREF(self->ob_cdcallbacks[type].ob_cdcallbackarg);
- self->ob_cdcallbacks[type].ob_cdcallbackarg = NULL;
+ Py_CLEAR(self->ob_cdcallbacks[type].ob_cdcallbackarg);
 
 Py_INCREF(Py_None);
 return Py_None;
@@ -668,10 +664,8 @@
 int i;
 
 for (i = 0; i < NCALLBACKS; i++) {
- Py_XDECREF(self->ob_cdcallbacks[i].ob_cdcallback);
- self->ob_cdcallbacks[i].ob_cdcallback = NULL;
- Py_XDECREF(self->ob_cdcallbacks[i].ob_cdcallbackarg);
- self->ob_cdcallbacks[i].ob_cdcallbackarg = NULL;
+ Py_CLEAR(self->ob_cdcallbacks[i].ob_cdcallback);
+ Py_CLEAR(self->ob_cdcallbacks[i].ob_cdcallbackarg);
 }
 CDdeleteparser(self->ob_cdparser);
 PyObject_Del(self);
diff --git a/Modules/flmodule.c b/Modules/flmodule.c
--- a/Modules/flmodule.c
+++ b/Modules/flmodule.c
@@ -97,10 +97,8 @@
 {
 int i, n;
 
- Py_XDECREF(g->ob_callback);
- g->ob_callback = NULL;
- Py_XDECREF(g->ob_callback_arg);
- g->ob_callback_arg = NULL;
+ Py_CLEAR(g->ob_callback);
+ Py_CLEAR(g->ob_callback_arg);
 if (allgenerics == NULL)
 return; /* No objects known yet */
 n = PyList_Size(allgenerics);
@@ -132,10 +130,8 @@
 /* The object is now unreachable for
 do_forms and check_forms, so
 delete it from the list of known objects */
- Py_XDECREF(g->ob_callback);
- g->ob_callback = NULL;
- Py_XDECREF(g->ob_callback_arg);
- g->ob_callback_arg = NULL;
+ Py_CLEAR(g->ob_callback);
+ Py_CLEAR(g->ob_callback_arg);
 PyList_SetItem(allgenerics, i, (PyObject *)NULL);
 nfreeslots++;
 }
diff --git a/Modules/readline.c b/Modules/readline.c
--- a/Modules/readline.c
+++ b/Modules/readline.c
@@ -206,8 +206,7 @@
 if (!PyArg_ParseTuple(args, buf, &function))
 return NULL;
 if (function == Py_None) {
- Py_XDECREF(*hook_var);
- *hook_var = NULL;
+ Py_CLEAR(*hook_var);
 }
 else if (PyCallable_Check(function)) {
 PyObject *tmp = *hook_var;
diff --git a/Modules/selectmodule.c b/Modules/selectmodule.c
--- a/Modules/selectmodule.c
+++ b/Modules/selectmodule.c
@@ -71,8 +71,7 @@
 {
 int i;
 for (i = 0; i < FD_SETSIZE + 1 && fd2obj[i].sentinel >= 0; i++) {
- Py_XDECREF(fd2obj[i].obj);
- fd2obj[i].obj = NULL;
+ Py_CLEAR(fd2obj[i].obj);
 }
 fd2obj[0].sentinel = -1;
 }
diff --git a/Modules/svmodule.c b/Modules/svmodule.c
--- a/Modules/svmodule.c
+++ b/Modules/svmodule.c
@@ -279,8 +279,7 @@
 (void)svUnlockCaptureData(self->ob_svideo->ob_svideo,
 self->ob_capture);
 self->ob_capture = NULL;
- Py_DECREF(self->ob_svideo);
- self->ob_svideo = NULL;
+ Py_CLEAR(self->ob_svideo);
 }
 PyObject_Del(self);
 }
diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -881,8 +881,7 @@
 _Py_ForgetReference((PyObject *) v);
 /* DECREF items deleted by shrinkage */
 for (i = newsize; i < oldsize; i++) {
- Py_XDECREF(v->ob_item[i]);
- v->ob_item[i] = NULL;
+ Py_CLEAR(v->ob_item[i]);
 }
 sv = PyObject_GC_Resize(PyTupleObject, v, newsize);
 if (sv == NULL) {
@@ -928,8 +927,7 @@
 #if PyTuple_MAXSAVESIZE > 0
 /* empty tuples are used all over the place and applications may
 * rely on the fact that an empty tuple is a singleton. */
- Py_XDECREF(free_list[0]);
- free_list[0] = NULL;
+ Py_CLEAR(free_list[0]);
 
 (void)PyTuple_ClearFreeList();
 #endif
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -3520,8 +3520,7 @@
 goto onError;
 return;
 onError:
- Py_DECREF(*exceptionObject);
- *exceptionObject = NULL;
+ Py_CLEAR(*exceptionObject);
 }
 }
 
@@ -4826,8 +4825,7 @@
 goto onError;
 return;
 onError:
- Py_DECREF(*exceptionObject);
- *exceptionObject = NULL;
+ Py_CLEAR(*exceptionObject);
 }
 }
 
diff --git a/Python/ceval.c b/Python/ceval.c
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -3240,8 +3240,7 @@
 if (co->co_flags & CO_GENERATOR) {
 /* Don't need to keep the reference to f_back, it will be set
 * when the generator is resumed. */
- Py_XDECREF(f->f_back);
- f->f_back = NULL;
+ Py_CLEAR(f->f_back);
 
 PCALL(PCALL_GENERATOR);
 
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -367,8 +367,7 @@
 result = call_trampoline(tstate, callback, frame, what, arg);
 if (result == NULL) {
 PyEval_SetTrace(NULL, NULL);
- Py_XDECREF(frame->f_trace);
- frame->f_trace = NULL;
+ Py_CLEAR(frame->f_trace);
 return -1;
 }
 if (result != Py_None) {
-- 
Repository URL: http://hg.python.org/cpython

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• Previous message: [Python-checkins] peps: Simplify PEP 101 a bit; remove instructions for "prev" directory.
• Next message: [Python-checkins] cpython (3.3): Issue #20437: Fixed 21 potential bugs when deleting objects references.
• Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

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