[Python-checkins] cpython (2.7): Issue #13380: add an internal function for resetting the ctypes caches

[meador.inge]

http://hg.python.org/cpython/rev/6783aa5c15ae
changeset:   73750:6783aa5c15ae
branch:      2.7
parent:      73745:e42be90eb9c5
user:        Meador Inge <meadori at gmail.com>
date:        Fri Nov 25 22:25:06 2011 -0600
summary:
  Issue #13380: add an internal function for resetting the ctypes caches

files:
  Lib/ctypes/__init__.py               |  28 +++++++++------
  Lib/ctypes/test/test_as_parameter.py |   1 +
  Lib/ctypes/test/test_functions.py    |   1 +
  Lib/test/regrtest.py                 |   7 ++++
  4 files changed, 26 insertions(+), 11 deletions(-)


diff --git a/Lib/ctypes/__init__.py b/Lib/ctypes/__init__.py
--- a/Lib/ctypes/__init__.py
+++ b/Lib/ctypes/__init__.py
@@ -262,6 +262,22 @@
 
 from _ctypes import POINTER, pointer, _pointer_type_cache
 
+def _reset_cache():
+    _pointer_type_cache.clear()
+    _c_functype_cache.clear()
+    if _os.name in ("nt", "ce"):
+        _win_functype_cache.clear()
+    # _SimpleCData.c_wchar_p_from_param
+    POINTER(c_wchar).from_param = c_wchar_p.from_param
+    # _SimpleCData.c_char_p_from_param
+    POINTER(c_char).from_param = c_char_p.from_param
+    _pointer_type_cache[None] = c_void_p
+    # XXX for whatever reasons, creating the first instance of a callback
+    # function is needed for the unittests on Win64 to succeed.  This MAY
+    # be a compiler bug, since the problem occurs only when _ctypes is
+    # compiled with the MS SDK compiler.  Or an uninitialized variable?
+    CFUNCTYPE(c_int)(lambda: None)
+
 try:
     from _ctypes import set_conversion_mode
 except ImportError:
@@ -278,8 +294,6 @@
     class c_wchar(_SimpleCData):
         _type_ = "u"
 
-    POINTER(c_wchar).from_param = c_wchar_p.from_param #_SimpleCData.c_wchar_p_from_param
-
     def create_unicode_buffer(init, size=None):
         """create_unicode_buffer(aString) -> character array
         create_unicode_buffer(anInteger) -> character array
@@ -298,8 +312,6 @@
             return buf
         raise TypeError(init)
 
-POINTER(c_char).from_param = c_char_p.from_param #_SimpleCData.c_char_p_from_param
-
 # XXX Deprecated
 def SetPointerType(pointer, cls):
     if _pointer_type_cache.get(cls, None) is not None:
@@ -458,8 +470,6 @@
             descr = FormatError(code).strip()
         return WindowsError(code, descr)
 
-_pointer_type_cache[None] = c_void_p
-
 if sizeof(c_uint) == sizeof(c_void_p):
     c_size_t = c_uint
     c_ssize_t = c_int
@@ -542,8 +552,4 @@
     elif sizeof(kind) == 8: c_uint64 = kind
 del(kind)
 
-# XXX for whatever reasons, creating the first instance of a callback
-# function is needed for the unittests on Win64 to succeed.  This MAY
-# be a compiler bug, since the problem occurs only when _ctypes is
-# compiled with the MS SDK compiler.  Or an uninitialized variable?
-CFUNCTYPE(c_int)(lambda: None)
+_reset_cache()
diff --git a/Lib/ctypes/test/test_as_parameter.py b/Lib/ctypes/test/test_as_parameter.py
--- a/Lib/ctypes/test/test_as_parameter.py
+++ b/Lib/ctypes/test/test_as_parameter.py
@@ -74,6 +74,7 @@
     def test_callbacks(self):
         f = dll._testfunc_callback_i_if
         f.restype = c_int
+        f.argtypes = None
 
         MyCallback = CFUNCTYPE(c_int, c_int)
 
diff --git a/Lib/ctypes/test/test_functions.py b/Lib/ctypes/test/test_functions.py
--- a/Lib/ctypes/test/test_functions.py
+++ b/Lib/ctypes/test/test_functions.py
@@ -250,6 +250,7 @@
     def test_callbacks(self):
         f = dll._testfunc_callback_i_if
         f.restype = c_int
+        f.argtypes = None
 
         MyCallback = CFUNCTYPE(c_int, c_int)
 
diff --git a/Lib/test/regrtest.py b/Lib/test/regrtest.py
--- a/Lib/test/regrtest.py
+++ b/Lib/test/regrtest.py
@@ -1076,6 +1076,13 @@
     filecmp._cache.clear()
     struct._clearcache()
     doctest.master = None
+    try:
+        import ctypes
+    except ImportError:
+        # Don't worry about resetting the cache if ctypes is not supported
+        pass
+    else:
+        ctypes._reset_cache()
 
     # Collect cyclic trash.
     gc.collect()

-- 
Repository URL: http://hg.python.org/cpython