import array
import ctypes
import sys
import unittest
from ctypes import (CDLL, CFUNCTYPE, Structure,
POINTER, pointer, _Pointer, _pointer_type_cache,
byref, sizeof,
c_void_p, c_char_p,
c_byte, c_ubyte, c_short, c_ushort, c_int, c_uint,
c_long, c_ulong, c_longlong, c_ulonglong,
c_float, c_double)
from test.support import import_helper
_ctypes_test = import_helper.import_module("_ctypes_test")
from ._support import (_CData, PyCPointerType, Py_TPFLAGS_DISALLOW_INSTANTIATION,
Py_TPFLAGS_IMMUTABLETYPE)
ctype_types = [c_byte, c_ubyte, c_short, c_ushort, c_int, c_uint,
c_long, c_ulong, c_longlong, c_ulonglong, c_double, c_float]
python_types = [int, int, int, int, int, int,
int, int, int, int, float, float]
class PointersTestCase(unittest.TestCase):
def test_inheritance_hierarchy(self):
self.assertEqual(_Pointer.mro(), [_Pointer, _CData, object])
self.assertEqual(PyCPointerType.__name__, "PyCPointerType")
self.assertEqual(type(PyCPointerType), type)
def test_type_flags(self):
for cls in _Pointer, PyCPointerType:
with self.subTest(cls=cls):
self.assertTrue(_Pointer.__flags__ & Py_TPFLAGS_IMMUTABLETYPE)
self.assertFalse(_Pointer.__flags__ & Py_TPFLAGS_DISALLOW_INSTANTIATION)
def test_metaclass_details(self):
# Cannot call the metaclass __init__ more than once
with self.assertRaisesRegex(SystemError, "already initialized"):
PyCPointerType.__init__(POINTER(c_byte), 'ptr', (), {})
def test_pointer_crash(self):
class A(POINTER(c_ulong)):
pass
POINTER(c_ulong)(c_ulong(22))
# Pointer can't set contents: has no _type_
self.assertRaises(TypeError, A, c_ulong(33))
def test_pass_pointers(self):
dll = CDLL(_ctypes_test.__file__)
func = dll._testfunc_p_p
if sizeof(c_longlong) == sizeof(c_void_p):
func.restype = c_longlong
else:
func.restype = c_long
i = c_int(12345678)
address = func(byref(i))
self.assertEqual(c_int.from_address(address).value, 12345678)
func.restype = POINTER(c_int)
res = func(pointer(i))
self.assertEqual(res.contents.value, 12345678)
self.assertEqual(res[0], 12345678)
def test_change_pointers(self):
dll = CDLL(_ctypes_test.__file__)
func = dll._testfunc_p_p
i = c_int(87654)
func.restype = POINTER(c_int)
func.argtypes = (POINTER(c_int),)
res = func(pointer(i))
self.assertEqual(res[0], 87654)
self.assertEqual(res.contents.value, 87654)
# C code: *res = 54345
res[0] = 54345
self.assertEqual(i.value, 54345)
# C code:
# int x = 12321;
# res = &x
x = c_int(12321)
res.contents = x
self.assertEqual(i.value, 54345)
x.value = -99
self.assertEqual(res.contents.value, -99)
def test_callbacks_with_pointers(self):
# a function type receiving a pointer
PROTOTYPE = CFUNCTYPE(c_int, POINTER(c_int))
self.result = []
def func(arg):
for i in range(10):
self.result.append(arg[i])
return 0
callback = PROTOTYPE(func)
dll = CDLL(_ctypes_test.__file__)
# This function expects a function pointer,
# and calls this with an integer pointer as parameter.
# The int pointer points to a table containing the numbers 1..10
doit = dll._testfunc_callback_with_pointer
doit(callback)
doit(callback)
def test_basics(self):
for ct, pt in zip(ctype_types, python_types):
i = ct(42)
p = pointer(i)
self.assertIs(type(p.contents), ct)
# p.contents is the same as p[0]
with self.assertRaises(TypeError):
del p[0]
def test_from_address(self):
a = array.array('i', [100, 200, 300, 400, 500])
addr = a.buffer_info()[0]
p = POINTER(POINTER(c_int))
def test_other(self):
class Table(Structure):
_fields_ = [("a", c_int),
("b", c_int),
("c", c_int)]
pt = pointer(Table(1, 2, 3))
self.assertEqual(pt.contents.a, 1)
self.assertEqual(pt.contents.b, 2)
self.assertEqual(pt.contents.c, 3)
pt.contents.c = 33
del _pointer_type_cache[Table]
def test_basic(self):
p = pointer(c_int(42))
# Although a pointer can be indexed, it has no length
self.assertRaises(TypeError, len, p)
self.assertEqual(p[0], 42)
self.assertEqual(p[0:1], [42])
self.assertEqual(p.contents.value, 42)
def test_charpp(self):
"""Test that a character pointer-to-pointer is correctly passed"""
dll = CDLL(_ctypes_test.__file__)
func = dll._testfunc_c_p_p
func.restype = c_char_p
argv = (c_char_p * 2)()
argc = c_int( 2 )
argv[0] = b'hello'
argv[1] = b'world'
result = func( byref(argc), argv )
self.assertEqual(result, b'world')
def test_bug_1467852(self):
# http://sourceforge.net/tracker/?func=detail&atid=532154&aid=1467852&group_id=71702
x = c_int(5)
dummy = []
for i in range(32000):
dummy.append(c_int(i))
y = c_int(6)
p = pointer(x)
pp = pointer(p)
q = pointer(y)
pp[0] = q # <==
self.assertEqual(p[0], 6)
def test_c_void_p(self):
# http://sourceforge.net/tracker/?func=detail&aid=1518190&group_id=5470&atid=105470
if sizeof(c_void_p) == 4:
self.assertEqual(c_void_p(0xFFFFFFFF).value,
c_void_p(-1).value)
self.assertEqual(c_void_p(0xFFFFFFFFFFFFFFFF).value,
c_void_p(-1).value)
elif sizeof(c_void_p) == 8:
self.assertEqual(c_void_p(0xFFFFFFFF).value,
0xFFFFFFFF)
self.assertEqual(c_void_p(0xFFFFFFFFFFFFFFFF).value,
c_void_p(-1).value)
self.assertEqual(c_void_p(0xFFFFFFFFFFFFFFFFFFFFFFFF).value,
c_void_p(-1).value)
self.assertRaises(TypeError, c_void_p, 3.14) # make sure floats are NOT accepted
self.assertRaises(TypeError, c_void_p, object()) # nor other objects
def test_pointers_bool(self):
# NULL pointers have a boolean False value, non-NULL pointers True.
self.assertEqual(bool(POINTER(c_int)()), False)
self.assertEqual(bool(pointer(c_int())), True)
self.assertEqual(bool(CFUNCTYPE(None)(0)), False)
self.assertEqual(bool(CFUNCTYPE(None)(42)), True)
# COM methods are boolean True:
if sys.platform == "win32":
mth = ctypes.WINFUNCTYPE(None)(42, "name", (), None)
self.assertEqual(bool(mth), True)
def test_pointer_type_name(self):
LargeNamedType = type('T' * 2 ** 25, (Structure,), {})
self.assertTrue(POINTER(LargeNamedType))
# to not leak references, we must clean _pointer_type_cache
del _pointer_type_cache[LargeNamedType]
def test_pointer_type_str_name(self):
large_string = 'T' * 2 ** 25
P = POINTER(large_string)
self.assertTrue(P)
# to not leak references, we must clean _pointer_type_cache
del _pointer_type_cache[id(P)]
def test_abstract(self):
self.assertRaises(TypeError, _Pointer.set_type, 42)
if __name__ == '__main__':
unittest.main()