[Python-checkins] cpython (3.3): Issue #20437: Fixed 21 potential bugs when deleting objects references.

Sun Feb 9 12:56:24 CET 2014

http://hg.python.org/cpython/rev/6adac0d9b933
changeset: 89085:6adac0d9b933
branch: 3.3
parent: 89068:c2538789c8cf
user: Serhiy Storchaka <storchaka at gmail.com>
date: Sun Feb 09 13:33:53 2014 +0200
summary:
 Issue #20437: Fixed 21 potential bugs when deleting objects references.
files:
 Misc/NEWS | 2 ++
 Modules/_ctypes/_ctypes.c | 18 ++++++------------
 Modules/_sqlite/cursor.c | 9 +++------
 Modules/posixmodule.c | 3 +--
 Modules/pyexpat.c | 3 +--
 Modules/readline.c | 5 ++---
 Modules/selectmodule.c | 3 +--
 Modules/signalmodule.c | 9 +++------
 Modules/syslogmodule.c | 3 +--
 Modules/zlibmodule.c | 3 +--
 Objects/frameobject.c | 3 +--
 Objects/tupleobject.c | 6 ++----
 Objects/unicodeobject.c | 12 ++++--------
 Python/ceval.c | 9 +++------
 Python/import.c | 6 ++----
 Python/sysmodule.c | 3 +--
 16 files changed, 34 insertions(+), 63 deletions(-)

diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,8 @@
 Core and Builtins
 -----------------
 
+- Issue #20437: Fixed 21 potential bugs when deleting objects references.
+
 - Issue #20538: UTF-7 incremental decoder produced inconsistant string when
 input was truncated in BASE64 section.
 
diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -159,10 +159,8 @@
 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;
@@ -2930,10 +2928,8 @@
 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)) {
@@ -2976,10 +2972,8 @@
 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/_sqlite/cursor.c b/Modules/_sqlite/cursor.c
--- a/Modules/_sqlite/cursor.c
+++ b/Modules/_sqlite/cursor.c
@@ -230,8 +230,7 @@
 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;
 }
@@ -443,8 +442,7 @@
 self->locked = 1;
 self->reset = 0;
 
- Py_XDECREF(self->next_row);
- self->next_row = NULL;
+ Py_CLEAR(self->next_row);
 
 if (multiple) {
 /* executemany() */
@@ -860,8 +858,7 @@
 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/posixmodule.c b/Modules/posixmodule.c
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -693,8 +693,7 @@
 static void
 path_cleanup(path_t *path) {
 if (path->cleanup) {
- Py_DECREF(path->cleanup);
- path->cleanup = NULL;
+ Py_CLEAR(path->cleanup);
 }
 }
 
diff --git a/Modules/pyexpat.c b/Modules/pyexpat.c
--- a/Modules/pyexpat.c
+++ b/Modules/pyexpat.c
@@ -314,8 +314,7 @@
 }
 else {
 if (trace_frame(tstate, f, PyTrace_RETURN, res) < 0) {
- Py_XDECREF(res);
- res = NULL;
+ Py_CLEAR(res);
 }
 }
 #else
diff --git a/Modules/readline.c b/Modules/readline.c
--- a/Modules/readline.c
+++ b/Modules/readline.c
@@ -231,8 +231,7 @@
 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;
@@ -827,7 +826,7 @@
 (r != Py_None && PyLong_AsLong(r) == -1 && PyErr_Occurred())) {
 goto error;
 }
- Py_XDECREF(r); r=NULL;
+ Py_CLEAR(r);
 
 if (0) {
 error:
diff --git a/Modules/selectmodule.c b/Modules/selectmodule.c
--- a/Modules/selectmodule.c
+++ b/Modules/selectmodule.c
@@ -74,8 +74,7 @@
 {
 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/signalmodule.c b/Modules/signalmodule.c
--- a/Modules/signalmodule.c
+++ b/Modules/signalmodule.c
@@ -1305,12 +1305,9 @@
 Py_XDECREF(func);
 }
 
- Py_XDECREF(IntHandler);
- IntHandler = NULL;
- Py_XDECREF(DefaultHandler);
- DefaultHandler = NULL;
- Py_XDECREF(IgnoreHandler);
- IgnoreHandler = NULL;
+ Py_CLEAR(IntHandler);
+ Py_CLEAR(DefaultHandler);
+ Py_CLEAR(IgnoreHandler);
 }
 
 
diff --git a/Modules/syslogmodule.c b/Modules/syslogmodule.c
--- a/Modules/syslogmodule.c
+++ b/Modules/syslogmodule.c
@@ -197,8 +197,7 @@
 {
 if (S_log_open) {
 closelog();
- Py_XDECREF(S_ident_o);
- S_ident_o = NULL;
+ Py_CLEAR(S_ident_o);
 S_log_open = 0;
 }
 Py_INCREF(Py_None);
diff --git a/Modules/zlibmodule.c b/Modules/zlibmodule.c
--- a/Modules/zlibmodule.c
+++ b/Modules/zlibmodule.c
@@ -392,8 +392,7 @@
 }
 
 error:
- Py_XDECREF(self);
- self = NULL;
+ Py_CLEAR(self);
 success:
 if (zdict.buf != NULL)
 PyBuffer_Release(&zdict);
diff --git a/Objects/frameobject.c b/Objects/frameobject.c
--- a/Objects/frameobject.c
+++ b/Objects/frameobject.c
@@ -952,8 +952,7 @@
 PyFrame_Fini(void)
 {
 (void)PyFrame_ClearFreeList();
- Py_XDECREF(builtin_object);
- builtin_object = NULL;
+ Py_CLEAR(builtin_object);
 }
 
 /* Print summary info about the state of the optimized allocator */
diff --git a/Objects/tupleobject.c b/Objects/tupleobject.c
--- a/Objects/tupleobject.c
+++ b/Objects/tupleobject.c
@@ -866,8 +866,7 @@
 _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) {
@@ -913,8 +912,7 @@
 #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
@@ -1846,8 +1846,7 @@
 {
 _Py_Identifier *tmp, *s = static_strings;
 while (s) {
- Py_DECREF(s->object);
- s->object = NULL;
+ Py_CLEAR(s->object);
 tmp = s->next;
 s->next = NULL;
 s = tmp;
@@ -4082,8 +4081,7 @@
 return;
 
 onError:
- Py_DECREF(*exceptionObject);
- *exceptionObject = NULL;
+ Py_CLEAR(*exceptionObject);
 }
 
 /* error handling callback helper:
@@ -6224,8 +6222,7 @@
 goto onError;
 return;
 onError:
- Py_DECREF(*exceptionObject);
- *exceptionObject = NULL;
+ Py_CLEAR(*exceptionObject);
 }
 }
 
@@ -8225,8 +8222,7 @@
 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
@@ -3049,8 +3049,7 @@
 if (call_trace(tstate->c_tracefunc,
 tstate->c_traceobj, f,
 PyTrace_RETURN, retval)) {
- Py_XDECREF(retval);
- retval = NULL;
+ Py_CLEAR(retval);
 why = WHY_EXCEPTION;
 }
 }
@@ -3068,8 +3067,7 @@
 else if (call_trace(tstate->c_profilefunc,
 tstate->c_profileobj, f,
 PyTrace_RETURN, retval)) {
- Py_XDECREF(retval);
- retval = NULL;
+ Py_CLEAR(retval);
 /* why = WHY_EXCEPTION; */
 }
 }
@@ -3426,8 +3424,7 @@
 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/import.c b/Python/import.c
--- a/Python/import.c
+++ b/Python/import.c
@@ -253,8 +253,7 @@
 void
 _PyImport_Fini(void)
 {
- Py_XDECREF(extensions);
- extensions = NULL;
+ Py_CLEAR(extensions);
 #ifdef WITH_THREAD
 if (import_lock != NULL) {
 PyThread_free_lock(import_lock);
@@ -497,8 +496,7 @@
 /* Somebody already imported the module,
 likely under a different name.
 XXX this should really not happen. */
- Py_DECREF(def->m_base.m_copy);
- def->m_base.m_copy = NULL;
+ Py_CLEAR(def->m_base.m_copy);
 }
 dict = PyModule_GetDict(mod);
 if (dict == NULL)
diff --git a/Python/sysmodule.c b/Python/sysmodule.c
--- a/Python/sysmodule.c
+++ b/Python/sysmodule.c
@@ -395,8 +395,7 @@
 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
