from ctypes import * from ctypes.test import need_symbol import unittest import sys class Test(unittest.TestCase): def test_array2pointer(self): array = (c_int * 3)(42, 17, 2) # casting an array to a pointer works. ptr = cast(array, POINTER(c_int)) self.assertEqual([ptr[i] for i in range(3)], [42, 17, 2]) if 2*sizeof(c_short) == sizeof(c_int): ptr = cast(array, POINTER(c_short)) if sys.byteorder == "little": self.assertEqual([ptr[i] for i in range(6)], [42, 0, 17, 0, 2, 0]) else: self.assertEqual([ptr[i] for i in range(6)], [0, 42, 0, 17, 0, 2]) def test_address2pointer(self): array = (c_int * 3)(42, 17, 2) address = addressof(array) ptr = cast(c_void_p(address), POINTER(c_int)) self.assertEqual([ptr[i] for i in range(3)], [42, 17, 2]) ptr = cast(address, POINTER(c_int)) self.assertEqual([ptr[i] for i in range(3)], [42, 17, 2]) def test_p2a_objects(self): array = (c_char_p * 5)() self.assertEqual(array._objects, None) array[0] = b"foo bar" self.assertEqual(array._objects, {'0': b"foo bar"}) p = cast(array, POINTER(c_char_p)) # array and p share a common _objects attribute self.assertIs(p._objects, array._objects) self.assertEqual(array._objects, {'0': b"foo bar", id(array): array}) p[0] = b"spam spam" self.assertEqual(p._objects, {'0': b"spam spam", id(array): array}) self.assertIs(array._objects, p._objects) p[1] = b"foo bar" self.assertEqual(p._objects, {'1': b'foo bar', '0': b"spam spam", id(array): array}) self.assertIs(array._objects, p._objects) def test_other(self): p = cast((c_int * 4)(1, 2, 3, 4), POINTER(c_int)) self.assertEqual(p[:4], [1,2, 3, 4]) self.assertEqual(p[:4:], [1, 2, 3, 4]) self.assertEqual(p[3:-1:-1], [4, 3, 2, 1]) self.assertEqual(p[:4:3], [1, 4]) c_int() self.assertEqual(p[:4], [1, 2, 3, 4]) self.assertEqual(p[:4:], [1, 2, 3, 4]) self.assertEqual(p[3:-1:-1], [4, 3, 2, 1]) self.assertEqual(p[:4:3], [1, 4]) p[2] = 96 self.assertEqual(p[:4], [1, 2, 96, 4]) self.assertEqual(p[:4:], [1, 2, 96, 4]) self.assertEqual(p[3:-1:-1], [4, 96, 2, 1]) self.assertEqual(p[:4:3], [1, 4]) c_int() self.assertEqual(p[:4], [1, 2, 96, 4]) self.assertEqual(p[:4:], [1, 2, 96, 4]) self.assertEqual(p[3:-1:-1], [4, 96, 2, 1]) self.assertEqual(p[:4:3], [1, 4]) def test_char_p(self): # This didn't work: bad argument to internal function s = c_char_p(b"hiho") self.assertEqual(cast(cast(s, c_void_p), c_char_p).value, b"hiho") @need_symbol('c_wchar_p') def test_wchar_p(self): s = c_wchar_p("hiho") self.assertEqual(cast(cast(s, c_void_p), c_wchar_p).value, "hiho") def test_bad_type_arg(self): # The type argument must be a ctypes pointer type. array_type = c_byte * sizeof(c_int) array = array_type() self.assertRaises(TypeError, cast, array, None) self.assertRaises(TypeError, cast, array, array_type) class Struct(Structure): _fields_ = [("a", c_int)] self.assertRaises(TypeError, cast, array, Struct) class MyUnion(Union): _fields_ = [("a", c_int)] self.assertRaises(TypeError, cast, array, MyUnion) if __name__ == "__main__": unittest.main() SIMPAN PERUBAHAN