Skip to content

Commit

Permalink
gh-126384: Add tests to verify the behavior of basic COM methods. (GH…
Browse files Browse the repository at this point in the history
  • Loading branch information
junkmd authored Nov 22, 2024
1 parent 0cb2017 commit 7725c03
Showing 1 changed file with 188 additions and 0 deletions.
188 changes: 188 additions & 0 deletions Lib/test/test_ctypes/test_win32_com_foreign_func.py
Original file line number Diff line number Diff line change
@@ -0,0 +1,188 @@
import ctypes
import gc
import sys
import unittest
from ctypes import POINTER, byref, c_void_p
from ctypes.wintypes import BYTE, DWORD, WORD

if sys.platform != "win32":
raise unittest.SkipTest("Windows-specific test")


from _ctypes import COMError
from ctypes import HRESULT


COINIT_APARTMENTTHREADED = 0x2
CLSCTX_SERVER = 5
S_OK = 0
OUT = 2
TRUE = 1
E_NOINTERFACE = -2147467262


class GUID(ctypes.Structure):
# https://learn.microsoft.com/en-us/windows/win32/api/guiddef/ns-guiddef-guid
_fields_ = [
("Data1", DWORD),
("Data2", WORD),
("Data3", WORD),
("Data4", BYTE * 8),
]


def create_proto_com_method(name, index, restype, *argtypes):
proto = ctypes.WINFUNCTYPE(restype, *argtypes)

def make_method(*args):
foreign_func = proto(index, name, *args)

def call(self, *args, **kwargs):
return foreign_func(self, *args, **kwargs)

return call

return make_method


def create_guid(name):
guid = GUID()
# https://learn.microsoft.com/en-us/windows/win32/api/combaseapi/nf-combaseapi-clsidfromstring
ole32.CLSIDFromString(name, byref(guid))
return guid


def is_equal_guid(guid1, guid2):
# https://learn.microsoft.com/en-us/windows/win32/api/objbase/nf-objbase-isequalguid
return ole32.IsEqualGUID(byref(guid1), byref(guid2))


ole32 = ctypes.oledll.ole32

IID_IUnknown = create_guid("{00000000-0000-0000-C000-000000000046}")
IID_IStream = create_guid("{0000000C-0000-0000-C000-000000000046}")
IID_IPersist = create_guid("{0000010C-0000-0000-C000-000000000046}")
CLSID_ShellLink = create_guid("{00021401-0000-0000-C000-000000000046}")

# https://learn.microsoft.com/en-us/windows/win32/api/unknwn/nf-unknwn-iunknown-queryinterface(refiid_void)
proto_query_interface = create_proto_com_method(
"QueryInterface", 0, HRESULT, POINTER(GUID), POINTER(c_void_p)
)
# https://learn.microsoft.com/en-us/windows/win32/api/unknwn/nf-unknwn-iunknown-addref
proto_add_ref = create_proto_com_method("AddRef", 1, ctypes.c_long)
# https://learn.microsoft.com/en-us/windows/win32/api/unknwn/nf-unknwn-iunknown-release
proto_release = create_proto_com_method("Release", 2, ctypes.c_long)
# https://learn.microsoft.com/en-us/windows/win32/api/objidl/nf-objidl-ipersist-getclassid
proto_get_class_id = create_proto_com_method(
"GetClassID", 3, HRESULT, POINTER(GUID)
)


class ForeignFunctionsThatWillCallComMethodsTests(unittest.TestCase):
def setUp(self):
# https://learn.microsoft.com/en-us/windows/win32/api/combaseapi/nf-combaseapi-coinitializeex
ole32.CoInitializeEx(None, COINIT_APARTMENTTHREADED)

def tearDown(self):
# https://learn.microsoft.com/en-us/windows/win32/api/combaseapi/nf-combaseapi-couninitialize
ole32.CoUninitialize()
gc.collect()

@staticmethod
def create_shelllink_persist(typ):
ppst = typ()
# https://learn.microsoft.com/en-us/windows/win32/api/combaseapi/nf-combaseapi-cocreateinstance
ole32.CoCreateInstance(
byref(CLSID_ShellLink),
None,
CLSCTX_SERVER,
byref(IID_IPersist),
byref(ppst),
)
return ppst

def test_without_paramflags_and_iid(self):
class IUnknown(c_void_p):
QueryInterface = proto_query_interface()
AddRef = proto_add_ref()
Release = proto_release()

class IPersist(IUnknown):
GetClassID = proto_get_class_id()

ppst = self.create_shelllink_persist(IPersist)

clsid = GUID()
hr_getclsid = ppst.GetClassID(byref(clsid))
self.assertEqual(S_OK, hr_getclsid)
self.assertEqual(TRUE, is_equal_guid(CLSID_ShellLink, clsid))

self.assertEqual(2, ppst.AddRef())
self.assertEqual(3, ppst.AddRef())

punk = IUnknown()
hr_qi = ppst.QueryInterface(IID_IUnknown, punk)
self.assertEqual(S_OK, hr_qi)
self.assertEqual(3, punk.Release())

with self.assertRaises(OSError) as e:
punk.QueryInterface(IID_IStream, IUnknown())
self.assertEqual(E_NOINTERFACE, e.exception.winerror)

self.assertEqual(2, ppst.Release())
self.assertEqual(1, ppst.Release())
self.assertEqual(0, ppst.Release())

def test_with_paramflags_and_without_iid(self):
class IUnknown(c_void_p):
QueryInterface = proto_query_interface(None)
AddRef = proto_add_ref()
Release = proto_release()

class IPersist(IUnknown):
GetClassID = proto_get_class_id(((OUT, "pClassID"),))

ppst = self.create_shelllink_persist(IPersist)

clsid = ppst.GetClassID()
self.assertEqual(TRUE, is_equal_guid(CLSID_ShellLink, clsid))

punk = IUnknown()
hr_qi = ppst.QueryInterface(IID_IUnknown, punk)
self.assertEqual(S_OK, hr_qi)
self.assertEqual(1, punk.Release())

with self.assertRaises(OSError) as e:
ppst.QueryInterface(IID_IStream, IUnknown())
self.assertEqual(E_NOINTERFACE, e.exception.winerror)

self.assertEqual(0, ppst.Release())

def test_with_paramflags_and_iid(self):
class IUnknown(c_void_p):
QueryInterface = proto_query_interface(None, IID_IUnknown)
AddRef = proto_add_ref()
Release = proto_release()

class IPersist(IUnknown):
GetClassID = proto_get_class_id(((OUT, "pClassID"),), IID_IPersist)

ppst = self.create_shelllink_persist(IPersist)

clsid = ppst.GetClassID()
self.assertEqual(TRUE, is_equal_guid(CLSID_ShellLink, clsid))

punk = IUnknown()
hr_qi = ppst.QueryInterface(IID_IUnknown, punk)
self.assertEqual(S_OK, hr_qi)
self.assertEqual(1, punk.Release())

with self.assertRaises(COMError) as e:
ppst.QueryInterface(IID_IStream, IUnknown())
self.assertEqual(E_NOINTERFACE, e.exception.hresult)

self.assertEqual(0, ppst.Release())


if __name__ == '__main__':
unittest.main()

0 comments on commit 7725c03

Please sign in to comment.