Issue #16628: Fix a memory leak in ctypes.resize().
diff --git a/Misc/NEWS b/Misc/NEWS
index 3894d2e..3c9f382 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -175,6 +175,8 @@
Library
-------
+- Issue #16628: Fix a memory leak in ctypes.resize().
+
- Issue #13120: Allow to call pdb.set_trace() from thread.
Patch by Ilya Sandler.
diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
index 8be5958..603b3b8 100644
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -2442,7 +2442,7 @@
assert(dict); /* Cannot be NULL for CDataObject instances */
Py_CLEAR(self->b_objects);
if ((self->b_needsfree)
- && ((size_t)dict->size > sizeof(self->b_value)))
+ && _CDataObject_HasExternalBuffer(self))
PyMem_Free(self->b_ptr);
self->b_ptr = NULL;
Py_CLEAR(self->b_base);
diff --git a/Modules/_ctypes/callproc.c b/Modules/_ctypes/callproc.c
index 1f3c1c0..3465995 100644
--- a/Modules/_ctypes/callproc.c
+++ b/Modules/_ctypes/callproc.c
@@ -1666,7 +1666,7 @@
obj->b_size = size;
goto done;
}
- if (obj->b_size <= sizeof(obj->b_value)) {
+ if (!_CDataObject_HasExternalBuffer(obj)) {
/* We are currently using the objects default buffer, but it
isn't large enough any more. */
void *ptr = PyMem_Malloc(size);
diff --git a/Modules/_ctypes/ctypes.h b/Modules/_ctypes/ctypes.h
index 27abe65..5237ac2 100644
--- a/Modules/_ctypes/ctypes.h
+++ b/Modules/_ctypes/ctypes.h
@@ -116,6 +116,7 @@
extern PyTypeObject PyCData_Type;
#define CDataObject_CheckExact(v) ((v)->ob_type == &PyCData_Type)
#define CDataObject_Check(v) PyObject_TypeCheck(v, &PyCData_Type)
+#define _CDataObject_HasExternalBuffer(v) ((v)->b_ptr != (char *)&(v)->b_value)
extern PyTypeObject PyCSimpleType_Type;
#define PyCSimpleTypeObject_CheckExact(v) ((v)->ob_type == &PyCSimpleType_Type)