Apply the patch #1532975 plus ideas from the patch #1533481.

ctypes instances no longer have the internal and undocumented
'_as_parameter_' attribute which was used to adapt them to foreign
function calls; this mechanism is replaced by a function pointer in
the type's stgdict.

In the 'from_param' class methods, try the _as_parameter_ attribute if
other conversions are not possible.

This makes the documented _as_parameter_ mechanism work as intended.

Change the ctypes version number to 1.0.1.

Lib/ctypes/__init__.py

@@ -5,7 +5,7 @@
 
 import os as _os, sys as _sys
 
-__version__ = "1.0.0"
+__version__ = "1.0.1"
 
 from _ctypes import Union, Structure, Array
 from _ctypes import _Pointer

Lib/ctypes/test/test_as_parameter.py

+import unittest
+from ctypes import *
+import _ctypes_test
+
+dll = CDLL(_ctypes_test.__file__)
+
+try:
+    CALLBACK_FUNCTYPE = WINFUNCTYPE
+except NameError:
+    # fake to enable this test on Linux
+    CALLBACK_FUNCTYPE = CFUNCTYPE
+
+class POINT(Structure):
+    _fields_ = [("x", c_int), ("y", c_int)]
+
+class BasicWrapTestCase(unittest.TestCase):
+    def wrap(self, param):
+        return param
+
+    def test_wchar_parm(self):
+        try:
+            c_wchar
+        except NameError:
+            return
+        f = dll._testfunc_i_bhilfd
+        f.argtypes = [c_byte, c_wchar, c_int, c_long, c_float, c_double]
+        result = f(self.wrap(1), self.wrap(u"x"), self.wrap(3), self.wrap(4), self.wrap(5.0), self.wrap(6.0))
+        self.failUnlessEqual(result, 139)
+        self.failUnless(type(result), int)
+
+    def test_pointers(self):
+        f = dll._testfunc_p_p
+        f.restype = POINTER(c_int)
+        f.argtypes = [POINTER(c_int)]
+
+        # This only works if the value c_int(42) passed to the
+        # function is still alive while the pointer (the result) is
+        # used.
+
+        v = c_int(42)
+
+        self.failUnlessEqual(pointer(v).contents.value, 42)
+        result = f(self.wrap(pointer(v)))
+        self.failUnlessEqual(type(result), POINTER(c_int))
+        self.failUnlessEqual(result.contents.value, 42)
+
+        # This on works...
+        result = f(self.wrap(pointer(v)))
+        self.failUnlessEqual(result.contents.value, v.value)
+
+        p = pointer(c_int(99))
+        result = f(self.wrap(p))
+        self.failUnlessEqual(result.contents.value, 99)
+
+    def test_shorts(self):
+        f = dll._testfunc_callback_i_if
+
+        args = []
+        expected = [262144, 131072, 65536, 32768, 16384, 8192, 4096, 2048,
+                    1024, 512, 256, 128, 64, 32, 16, 8, 4, 2, 1]
+
+        def callback(v):
+            args.append(v)
+
+        CallBack = CFUNCTYPE(c_int, c_int)
+
+        cb = CallBack(callback)
+        f(self.wrap(2**18), self.wrap(cb))
+        self.failUnlessEqual(args, expected)
+
+    ################################################################
+
+    def test_callbacks(self):
+        f = dll._testfunc_callback_i_if
+        f.restype = c_int
+
+        MyCallback = CFUNCTYPE(c_int, c_int)
+
+        def callback(value):
+            #print "called back with", value
+            return value
+
+        cb = MyCallback(callback)
+
+        result = f(self.wrap(-10), self.wrap(cb))
+        self.failUnlessEqual(result, -18)
+
+        # test with prototype
+        f.argtypes = [c_int, MyCallback]
+        cb = MyCallback(callback)
+
+        result = f(self.wrap(-10), self.wrap(cb))
+        self.failUnlessEqual(result, -18)
+
+        result = f(self.wrap(-10), self.wrap(cb))
+        self.failUnlessEqual(result, -18)
+
+        AnotherCallback = CALLBACK_FUNCTYPE(c_int, c_int, c_int, c_int, c_int)
+
+        # check that the prototype works: we call f with wrong
+        # argument types
+        cb = AnotherCallback(callback)
+        self.assertRaises(ArgumentError, f, self.wrap(-10), self.wrap(cb))
+
+    def test_callbacks_2(self):
+        # Can also use simple datatypes as argument type specifiers
+        # for the callback function.
+        # In this case the call receives an instance of that type
+        f = dll._testfunc_callback_i_if
+        f.restype = c_int
+
+        MyCallback = CFUNCTYPE(c_int, c_int)
+
+        f.argtypes = [c_int, MyCallback]
+
+        def callback(value):
+            #print "called back with", value
+            self.failUnlessEqual(type(value), int)
+            return value
+
+        cb = MyCallback(callback)
+        result = f(self.wrap(-10), self.wrap(cb))
+        self.failUnlessEqual(result, -18)
+
+    def test_longlong_callbacks(self):
+
+        f = dll._testfunc_callback_q_qf
+        f.restype = c_longlong
+
+        MyCallback = CFUNCTYPE(c_longlong, c_longlong)
+
+        f.argtypes = [c_longlong, MyCallback]
+
+        def callback(value):
+            self.failUnless(isinstance(value, (int, long)))
+            return value & 0x7FFFFFFF
+
+        cb = MyCallback(callback)
+
+        self.failUnlessEqual(13577625587, int(f(self.wrap(1000000000000), self.wrap(cb))))
+
+    def test_byval(self):
+        # without prototype
+        ptin = POINT(1, 2)
+        ptout = POINT()
+        # EXPORT int _testfunc_byval(point in, point *pout)
+        result = dll._testfunc_byval(ptin, byref(ptout))
+        got = result, ptout.x, ptout.y
+        expected = 3, 1, 2
+        self.failUnlessEqual(got, expected)
+
+        # with prototype
+        ptin = POINT(101, 102)
+        ptout = POINT()
+        dll._testfunc_byval.argtypes = (POINT, POINTER(POINT))
+        dll._testfunc_byval.restype = c_int
+        result = dll._testfunc_byval(self.wrap(ptin), byref(ptout))
+        got = result, ptout.x, ptout.y
+        expected = 203, 101, 102
+        self.failUnlessEqual(got, expected)
+
+    def test_struct_return_2H(self):
+        class S2H(Structure):
+            _fields_ = [("x", c_short),
+                        ("y", c_short)]
+        dll.ret_2h_func.restype = S2H
+        dll.ret_2h_func.argtypes = [S2H]
+        inp = S2H(99, 88)
+        s2h = dll.ret_2h_func(self.wrap(inp))
+        self.failUnlessEqual((s2h.x, s2h.y), (99*2, 88*3))
+
+    def test_struct_return_8H(self):
+        class S8I(Structure):
+            _fields_ = [("a", c_int),
+                        ("b", c_int),
+                        ("c", c_int),
+                        ("d", c_int),
+                        ("e", c_int),
+                        ("f", c_int),
+                        ("g", c_int),
+                        ("h", c_int)]
+        dll.ret_8i_func.restype = S8I
+        dll.ret_8i_func.argtypes = [S8I]
+        inp = S8I(9, 8, 7, 6, 5, 4, 3, 2)
+        s8i = dll.ret_8i_func(self.wrap(inp))
+        self.failUnlessEqual((s8i.a, s8i.b, s8i.c, s8i.d, s8i.e, s8i.f, s8i.g, s8i.h),
+                             (9*2, 8*3, 7*4, 6*5, 5*6, 4*7, 3*8, 2*9))
+
+#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+class AsParamWrapper(object):
+    def __init__(self, param):
+        self._as_parameter_ = param
+
+class AsParamWrapperTestCase(BasicWrapTestCase):
+    wrap = AsParamWrapper
+
+#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+class AsParamPropertyWrapper(object):
+    def __init__(self, param):
+        self._param = param
+
+    def getParameter(self):
+        return self._param
+    _as_parameter_ = property(getParameter)
+
+class AsParamPropertyWrapperTestCase(BasicWrapTestCase):
+    wrap = AsParamPropertyWrapper
+
+#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+if __name__ == '__main__':
+    unittest.main()

Lib/ctypes/test/test_numbers.py

@@ -19,7 +19,7 @@ def valid_ranges(*types):
         result.append((min(a, b, c, d), max(a, b, c, d)))
     return result
 
-ArgType = type(c_int(0)._as_parameter_)
+ArgType = type(byref(c_int(0)))
 
 unsigned_types = [c_ubyte, c_ushort, c_uint, c_ulong]
 signed_types = [c_byte, c_short, c_int, c_long, c_longlong]
@@ -80,19 +80,6 @@ class NumberTestCase(unittest.TestCase):
         for t in signed_types + unsigned_types + float_types:
             self.failUnlessEqual(ArgType, type(t.from_param(0)))
 
-    def test_as_parameter(self):
-        # The _as_parameter_ property must also
-        # be a PyCArgObject instance
-        for t in signed_types + unsigned_types + float_types:
-            parm = t()._as_parameter_
-            self.failUnlessEqual(ArgType, type(parm))
-
-            # _as_parameter_ is readonly!
-            #
-            # Python 2.3 and 2.4 raise a TypeError when trying to set
-            # a readonly attribute, 2.5 raises an AttributeError.
-            self.assertRaises((AttributeError, TypeError), setattr, t(), "_as_parameter_", None)
-
     def test_byref(self):
         # calling byref returns also a PyCArgObject instance
         for t in signed_types + unsigned_types + float_types:

Lib/ctypes/test/test_prototypes.py

@@ -125,13 +125,18 @@ class CharPointersTestCase(unittest.TestCase):
             self.failUnlessEqual(None, func(c_wchar_p(None)))
             self.failUnlessEqual(u"123", func(c_wchar_p(u"123")))
 
-##    def test_instance(self):
-##        func = testdll._testfunc_p_p
+    def test_instance(self):
+        func = testdll._testfunc_p_p
+        func.restype = c_void_p
+
+        class X:
+            _as_parameter_ = None
 
-##        class X:
-##            _as_parameter_ = 0
+        func.argtypes = c_void_p,
+        self.failUnlessEqual(None, func(X()))
 
-##        self.failUnlessEqual(0, func(X()))
+        func.argtypes = None
+        self.failUnlessEqual(None, func(X()))
 
 try:
     c_wchar

Misc/NEWS

@@ -66,6 +66,10 @@ Library
 Extension Modules
 -----------------
 
+- Patch #1532975 was applied, which fixes Bug #1533481: ctypes now
+  uses the _as_parameter_ attribute when objects are passed to foreign
+  function calls.  The ctypes version number was changed to 1.0.1.
+
 - Bug #1530559, struct.pack raises TypeError where it used to convert.
   Passing float arguments to struct.pack when integers are expected
   now triggers a DeprecationWarning.

Modules/_ctypes/callproc.c

@@ -465,7 +465,21 @@ struct argument {
  */
 static int ConvParam(PyObject *obj, int index, struct argument *pa)
 {
+	StgDictObject *dict;
 	pa->keep = NULL; /* so we cannot forget it later */
+
+	dict = PyObject_stgdict(obj);
+	if (dict) {
+		PyCArgObject *carg;
+		assert(dict->paramfunc);
+		/* If it has an stgdict, it is a CDataObject */
+		carg = dict->paramfunc((CDataObject *)obj);
+		pa->ffi_type = carg->pffi_type;
+		memcpy(&pa->value, &carg->value, sizeof(pa->value));
+		pa->keep = (PyObject *)carg;
+		return 0;
+	}
+
 	if (PyCArg_CheckExact(obj)) {
 		PyCArgObject *carg = (PyCArgObject *)obj;
 		pa->ffi_type = carg->pffi_type;
@@ -548,25 +562,12 @@ static int ConvParam(PyObject *obj, int index, struct argument *pa)
 		   as parameters (they have to expose the '_as_parameter_'
 		   attribute)
 		*/
-		if (arg == 0) {
-			PyErr_Format(PyExc_TypeError,
-				     "Don't know how to convert parameter %d", index);
-			return -1;
-		}
-		if (PyCArg_CheckExact(arg)) {
-			PyCArgObject *carg = (PyCArgObject *)arg;
-			pa->ffi_type = carg->pffi_type;
-			memcpy(&pa->value, &carg->value, sizeof(pa->value));
-			pa->keep = arg;
-			return 0;
-		}
-		if (PyInt_Check(arg)) {
-			pa->ffi_type = &ffi_type_sint;
-			pa->value.i = PyInt_AS_LONG(arg);
-			pa->keep = arg;
-			return 0;
-		}
+		if (arg) {
+			int result;
+			result = ConvParam(arg, index, pa);
 			Py_DECREF(arg);
+			return result;
+		}
 		PyErr_Format(PyExc_TypeError,
 			     "Don't know how to convert parameter %d", index);
 		return -1;

Modules/_ctypes/ctypes.h

@@ -23,9 +23,11 @@ typedef int Py_ssize_t;
 #define PY_LONG_LONG LONG_LONG
 #endif
 
+typedef struct tagPyCArgObject PyCArgObject;
 typedef struct tagCDataObject CDataObject;
 typedef PyObject *(* GETFUNC)(void *, unsigned size);
 typedef PyObject *(* SETFUNC)(void *, PyObject *value, unsigned size);
+typedef PyCArgObject *(* PARAMFUNC)(CDataObject *obj);
 
 /* A default buffer in CDataObject, which can be used for small C types.  If
 this buffer is too small, PyMem_Malloc will be called to create a larger one,
@@ -205,6 +207,7 @@ typedef struct {
 	PyObject *proto;	/* Only for Pointer/ArrayObject */
 	SETFUNC setfunc;	/* Only for simple objects */
 	GETFUNC getfunc;	/* Only for simple objects */
+	PARAMFUNC paramfunc;
 
 	/* Following fields only used by CFuncPtrType_Type instances */
 	PyObject *argtypes;	/* tuple of CDataObjects */
@@ -283,7 +286,7 @@ PyObject *_CallProc(PPROC pProc,
 
 #define DICTFLAG_FINAL 0x1000
 
-typedef struct {
+struct tagPyCArgObject {
 	PyObject_HEAD
 	ffi_type *pffi_type;
 	char tag;
@@ -302,7 +305,7 @@ typedef struct {
 	} value;
 	PyObject *obj;
 	int size; /* for the 'V' tag */
-} PyCArgObject;
+};
 
 extern PyTypeObject PyCArg_Type;
 extern PyCArgObject *new_CArgObject(void);