Python ctypes 模块，_pointer_type_cache() 实例源码

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

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[Table]

def test(self):
        class POINT(Structure):
            _fields_ = [("x", c_int), ("y", c_int)]
        class RECT(Structure):
            _fields_ = [("a", POINTER(POINT)),
                        ("b", POINTER(POINT))]
        r = RECT()
        p1 = POINT(1, 2)

        r.a = pointer(p1)
        r.b = pointer(p1)
##        from pprint import pprint as pp
##        pp(p1._objects)
##        pp(r._objects)

        r.a[0].x = 42
        r.a[0].y = 99

        # to avoid leaking when tests are run several times
        # clean up the types left in the cache.
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[POINT]

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

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[Table]

def test(self):
        class POINT(Structure):
            _fields_ = [("x", c_int), ("y", c_int)]
        class RECT(Structure):
            _fields_ = [("a", POINTER(POINT)),
                        ("b", POINTER(POINT))]
        r = RECT()
        p1 = POINT(1, 2)

        r.a = pointer(p1)
        r.b = pointer(p1)
##        from pprint import pprint as pp
##        pp(p1._objects)
##        pp(r._objects)

        r.a[0].x = 42
        r.a[0].y = 99

        # to avoid leaking when tests are run several times
        # clean up the types left in the cache.
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[POINT]

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

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[Table]

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

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[Table]

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

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[Table]

def test(self):
        class POINT(Structure):
            _fields_ = [("x", c_int), ("y", c_int)]
        class RECT(Structure):
            _fields_ = [("a", POINTER(POINT)),
                        ("b", POINTER(POINT))]
        r = RECT()
        p1 = POINT(1, 2)

        r.a = pointer(p1)
        r.b = pointer(p1)
##        from pprint import pprint as pp
##        pp(p1._objects)
##        pp(r._objects)

        r.a[0].x = 42
        r.a[0].y = 99

        # to avoid leaking when tests are run several times
        # clean up the types left in the cache.
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[POINT]

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

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[Table]

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

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[Table]

def test(self):
        class POINT(Structure):
            _fields_ = [("x", c_int), ("y", c_int)]
        class RECT(Structure):
            _fields_ = [("a", POINTER(POINT)),
                        ("b", POINTER(POINT))]
        r = RECT()
        p1 = POINT(1, 2)

        r.a = pointer(p1)
        r.b = pointer(p1)
##        from pprint import pprint as pp
##        pp(p1._objects)
##        pp(r._objects)

        r.a[0].x = 42
        r.a[0].y = 99

        # to avoid leaking when tests are run several times
        # clean up the types left in the cache.
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[POINT]

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

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[Table]

def test(self):
        class POINT(Structure):
            _fields_ = [("x", c_int), ("y", c_int)]
        class RECT(Structure):
            _fields_ = [("a", POINTER(POINT)),
                        ("b", POINTER(POINT))]
        r = RECT()
        p1 = POINT(1, 2)

        r.a = pointer(p1)
        r.b = pointer(p1)
##        from pprint import pprint as pp
##        pp(p1._objects)
##        pp(r._objects)

        r.a[0].x = 42
        r.a[0].y = 99

        # to avoid leaking when tests are run several times
        # clean up the types left in the cache.
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[POINT]

def test_struct_struct(self):
        # nested structures with different byteorders

        # create nested structures with given byteorders and set memory to data

        for nested, data in (
            (BigEndianStructure, b'\0\0\0\1\0\0\0\2'),
            (LittleEndianStructure, b'\1\0\0\0\2\0\0\0'),
        ):
            for parent in (
                BigEndianStructure,
                LittleEndianStructure,
                Structure,
            ):
                class NestedStructure(nested):
                    _fields_ = [("x", c_uint32),
                                ("y", c_uint32)]

                class TestStructure(parent):
                    _fields_ = [("point", NestedStructure)]

                self.assertEqual(len(data), sizeof(TestStructure))
                ptr = POINTER(TestStructure)
                s = cast(data, ptr)[0]
                del ctypes._pointer_type_cache[TestStructure]
                self.assertEqual(s.point.x, 1)
                self.assertEqual(s.point.y, 2)

def test_frozentable(self):
        # Python exports a PyImport_FrozenModules symbol. This is a
        # pointer to an array of struct _frozen entries.  The end of the
        # array is marked by an entry containing a NULL name and zero
        # size.

        # In standard Python, this table contains a __hello__
        # module, and a __phello__ package containing a spam
        # module.
        class struct_frozen(Structure):
            _fields_ = [("name", c_char_p),
                        ("code", POINTER(c_ubyte)),
                        ("size", c_int)]
        FrozenTable = POINTER(struct_frozen)

        ft = FrozenTable.in_dll(pythonapi, "PyImport_FrozenModules")
        # ft is a pointer to the struct_frozen entries:
        items = []
        for entry in ft:
            # This is dangerous. We *can* iterate over a pointer, but
            # the loop will not terminate (maybe with an access
            # violation;-) because the pointer instance has no size.
            if entry.name is None:
                break
            items.append((entry.name, entry.size))

        expected = [("__hello__", 104),
                    ("__phello__", -104),
                    ("__phello__.spam", 104)]
        self.assertEqual(items, expected)

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[struct_frozen]

def test_incomplete_example(self):
        lpcell = POINTER("cell")
        class cell(Structure):
            _fields_ = [("name", c_char_p),
                        ("next", lpcell)]

        SetPointerType(lpcell, cell)

        c1 = cell()
        c1.name = "foo"
        c2 = cell()
        c2.name = "bar"

        c1.next = pointer(c2)
        c2.next = pointer(c1)

        p = c1

        result = []
        for i in range(8):
            result.append(p.name)
            p = p.next[0]
        self.assertEqual(result, ["foo", "bar"] * 4)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[cell]

################################################################

def test_struct_struct(self):
        # nested structures with different byteorders

        # create nested structures with given byteorders and set memory to data

        for nested, data in (
            (BigEndianStructure, b'\0\0\0\1\0\0\0\2'),
            (LittleEndianStructure, b'\1\0\0\0\2\0\0\0'),
        ):
            for parent in (
                BigEndianStructure,
                LittleEndianStructure,
                Structure,
            ):
                class NestedStructure(nested):
                    _fields_ = [("x", c_uint32),
                                ("y", c_uint32)]

                class TestStructure(parent):
                    _fields_ = [("point", NestedStructure)]

                self.assertEqual(len(data), sizeof(TestStructure))
                ptr = POINTER(TestStructure)
                s = cast(data, ptr)[0]
                del ctypes._pointer_type_cache[TestStructure]
                self.assertEqual(s.point.x, 1)
                self.assertEqual(s.point.y, 2)

def test_frozentable(self):
            # Python exports a PyImport_FrozenModules symbol. This is a
            # pointer to an array of struct _frozen entries.  The end of the
            # array is marked by an entry containing a NULL name and zero
            # size.

            # In standard Python, this table contains a __hello__
            # module, and a __phello__ package containing a spam
            # module.
            class struct_frozen(Structure):
                _fields_ = [("name", c_char_p),
                            ("code", POINTER(c_ubyte)),
                            ("size", c_int)]
            FrozenTable = POINTER(struct_frozen)

            ft = FrozenTable.in_dll(pydll, "PyImport_FrozenModules")
            # ft is a pointer to the struct_frozen entries:
            items = []
            for entry in ft:
                # This is dangerous. We *can* iterate over a pointer, but
                # the loop will not terminate (maybe with an access
                # violation;-) because the pointer instance has no size.
                if entry.name is None:
                    break
                items.append((entry.name, entry.size))
            import sys
            if sys.version_info[:2] >= (2, 3):
                expected = [("__hello__", 104), ("__phello__", -104), ("__phello__.spam", 104)]
            else:
                expected = [("__hello__", 100), ("__phello__", -100), ("__phello__.spam", 100)]
            self.assertEqual(items, expected)

            from ctypes import _pointer_type_cache
            del _pointer_type_cache[struct_frozen]

def test_incomplete_example(self):
        lpcell = POINTER("cell")
        class cell(Structure):
            _fields_ = [("name", c_char_p),
                        ("next", lpcell)]

        SetPointerType(lpcell, cell)

        c1 = cell()
        c1.name = b"foo"
        c2 = cell()
        c2.name = b"bar"

        c1.next = pointer(c2)
        c2.next = pointer(c1)

        p = c1

        result = []
        for i in range(8):
            result.append(p.name)
            p = p.next[0]
        self.assertEqual(result, [b"foo", b"bar"] * 4)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[cell]

################################################################

def test_struct_struct(self):
        # nested structures with different byteorders

        # create nested structures with given byteorders and set memory to data

        for nested, data in (
            (BigEndianStructure, b'\0\0\0\1\0\0\0\2'),
            (LittleEndianStructure, b'\1\0\0\0\2\0\0\0'),
        ):
            for parent in (
                BigEndianStructure,
                LittleEndianStructure,
                Structure,
            ):
                class NestedStructure(nested):
                    _fields_ = [("x", c_uint32),
                                ("y", c_uint32)]

                class TestStructure(parent):
                    _fields_ = [("point", NestedStructure)]

                self.assertEqual(len(data), sizeof(TestStructure))
                ptr = POINTER(TestStructure)
                s = cast(data, ptr)[0]
                del ctypes._pointer_type_cache[TestStructure]
                self.assertEqual(s.point.x, 1)
                self.assertEqual(s.point.y, 2)

def test_frozentable(self):
        # Python exports a PyImport_FrozenModules symbol. This is a
        # pointer to an array of struct _frozen entries.  The end of the
        # array is marked by an entry containing a NULL name and zero
        # size.

        # In standard Python, this table contains a __hello__
        # module, and a __phello__ package containing a spam
        # module.
        class struct_frozen(Structure):
            _fields_ = [("name", c_char_p),
                        ("code", POINTER(c_ubyte)),
                        ("size", c_int)]
        FrozenTable = POINTER(struct_frozen)

        ft = FrozenTable.in_dll(pythonapi, "PyImport_FrozenModules")
        # ft is a pointer to the struct_frozen entries:
        items = []
        for entry in ft:
            # This is dangerous. We *can* iterate over a pointer, but
            # the loop will not terminate (maybe with an access
            # violation;-) because the pointer instance has no size.
            if entry.name is None:
                break
            items.append((entry.name, entry.size))

        expected = [("__hello__", 104),
                    ("__phello__", -104),
                    ("__phello__.spam", 104)]
        self.assertEqual(items, expected)

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[struct_frozen]

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
        from ctypes import _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
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[id(P)]

def test_incomplete_example(self):
        lpcell = POINTER("cell")
        class cell(Structure):
            _fields_ = [("name", c_char_p),
                        ("next", lpcell)]

        SetPointerType(lpcell, cell)

        c1 = cell()
        c1.name = "foo"
        c2 = cell()
        c2.name = "bar"

        c1.next = pointer(c2)
        c2.next = pointer(c1)

        p = c1

        result = []
        for i in range(8):
            result.append(p.name)
            p = p.next[0]
        self.assertEqual(result, ["foo", "bar"] * 4)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[cell]

################################################################

def test_with_refcounts(runner, verbosity, testcase):
    """Run testcase several times, tracking reference counts."""
    import gc
    import ctypes
    ptc = ctypes._pointer_type_cache.copy()
    cfc = ctypes._c_functype_cache.copy()
    wfc = ctypes._win_functype_cache.copy()

    # when searching for refcount leaks, we have to manually reset any
    # caches that ctypes has.
    def cleanup():
        ctypes._pointer_type_cache = ptc.copy()
        ctypes._c_functype_cache = cfc.copy()
        ctypes._win_functype_cache = wfc.copy()
        gc.collect()

    test = unittest.makeSuite(testcase)
    for i in range(5):
        rc = sys.gettotalrefcount()
        runner.run(test)
        cleanup()
    COUNT = 5
    refcounts = [None] * COUNT
    for i in range(COUNT):
        rc = sys.gettotalrefcount()
        runner.run(test)
        cleanup()
        refcounts[i] = sys.gettotalrefcount() - rc
    if filter(None, refcounts):
        print "%s leaks:\n\t" % testcase, refcounts
    elif verbosity:
        print "%s: ok." % testcase

def test_struct_by_value(self):
        class POINT(Structure):
            _fields_ = [("x", c_long),
                        ("y", c_long)]

        class RECT(Structure):
            _fields_ = [("left", c_long),
                        ("top", c_long),
                        ("right", c_long),
                        ("bottom", c_long)]

        dll = CDLL(_ctypes_test.__file__)

        pt = POINT(15, 25)
        left = c_long.in_dll(dll, 'left')
        top = c_long.in_dll(dll, 'top')
        right = c_long.in_dll(dll, 'right')
        bottom = c_long.in_dll(dll, 'bottom')
        rect = RECT(left, top, right, bottom)
        PointInRect = dll.PointInRect
        PointInRect.argtypes = [POINTER(RECT), POINT]
        self.assertEqual(1, PointInRect(byref(rect), pt))

        ReturnRect = dll.ReturnRect
        ReturnRect.argtypes = [c_int, RECT, POINTER(RECT), POINT, RECT,
                               POINTER(RECT), POINT, RECT]
        ReturnRect.restype = RECT
        for i in range(4):
            ret = ReturnRect(i, rect, pointer(rect), pt, rect,
                         byref(rect), pt, rect)
            # the c function will check and modify ret if something is
            # passed in improperly
            self.assertEqual(ret.left, left.value)
            self.assertEqual(ret.right, right.value)
            self.assertEqual(ret.top, top.value)
            self.assertEqual(ret.bottom, bottom.value)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[RECT]

def test_struct_struct(self):
        # nested structures with different byteorders

        # create nested structures with given byteorders and set memory to data

        for nested, data in (
            (BigEndianStructure, b'\0\0\0\1\0\0\0\2'),
            (LittleEndianStructure, b'\1\0\0\0\2\0\0\0'),
        ):
            for parent in (
                BigEndianStructure,
                LittleEndianStructure,
                Structure,
            ):
                class NestedStructure(nested):
                    _fields_ = [("x", c_uint32),
                                ("y", c_uint32)]

                class TestStructure(parent):
                    _fields_ = [("point", NestedStructure)]

                self.assertEqual(len(data), sizeof(TestStructure))
                ptr = POINTER(TestStructure)
                s = cast(data, ptr)[0]
                del ctypes._pointer_type_cache[TestStructure]
                self.assertEqual(s.point.x, 1)
                self.assertEqual(s.point.y, 2)

def test_frozentable(self):
        # Python exports a PyImport_FrozenModules symbol. This is a
        # pointer to an array of struct _frozen entries.  The end of the
        # array is marked by an entry containing a NULL name and zero
        # size.

        # In standard Python, this table contains a __hello__
        # module, and a __phello__ package containing a spam
        # module.
        class struct_frozen(Structure):
            _fields_ = [("name", c_char_p),
                        ("code", POINTER(c_ubyte)),
                        ("size", c_int)]
        FrozenTable = POINTER(struct_frozen)

        ft = FrozenTable.in_dll(pythonapi, "PyImport_FrozenModules")
        # ft is a pointer to the struct_frozen entries:
        items = []
        for entry in ft:
            # This is dangerous. We *can* iterate over a pointer, but
            # the loop will not terminate (maybe with an access
            # violation;-) because the pointer instance has no size.
            if entry.name is None:
                break
            items.append((entry.name, entry.size))

        expected = [("__hello__", 104),
                    ("__phello__", -104),
                    ("__phello__.spam", 104)]
        self.assertEqual(items, expected)

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[struct_frozen]

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
        from ctypes import _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
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[id(P)]

def test_incomplete_example(self):
        lpcell = POINTER("cell")
        class cell(Structure):
            _fields_ = [("name", c_char_p),
                        ("next", lpcell)]

        SetPointerType(lpcell, cell)

        c1 = cell()
        c1.name = "foo"
        c2 = cell()
        c2.name = "bar"

        c1.next = pointer(c2)
        c2.next = pointer(c1)

        p = c1

        result = []
        for i in range(8):
            result.append(p.name)
            p = p.next[0]
        self.assertEqual(result, ["foo", "bar"] * 4)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[cell]

################################################################

def test_with_refcounts(runner, verbosity, testcase):
    """Run testcase several times, tracking reference counts."""
    import gc
    import ctypes
    ptc = ctypes._pointer_type_cache.copy()
    cfc = ctypes._c_functype_cache.copy()
    wfc = ctypes._win_functype_cache.copy()

    # when searching for refcount leaks, we have to manually reset any
    # caches that ctypes has.
    def cleanup():
        ctypes._pointer_type_cache = ptc.copy()
        ctypes._c_functype_cache = cfc.copy()
        ctypes._win_functype_cache = wfc.copy()
        gc.collect()

    test = unittest.makeSuite(testcase)
    for i in range(5):
        rc = sys.gettotalrefcount()
        runner.run(test)
        cleanup()
    COUNT = 5
    refcounts = [None] * COUNT
    for i in range(COUNT):
        rc = sys.gettotalrefcount()
        runner.run(test)
        cleanup()
        refcounts[i] = sys.gettotalrefcount() - rc
    if filter(None, refcounts):
        print "%s leaks:\n\t" % testcase, refcounts
    elif verbosity:
        print "%s: ok." % testcase

def test_struct_by_value(self):
        class POINT(Structure):
            _fields_ = [("x", c_long),
                        ("y", c_long)]

        class RECT(Structure):
            _fields_ = [("left", c_long),
                        ("top", c_long),
                        ("right", c_long),
                        ("bottom", c_long)]

        dll = CDLL(_ctypes_test.__file__)

        pt = POINT(15, 25)
        left = c_long.in_dll(dll, 'left')
        top = c_long.in_dll(dll, 'top')
        right = c_long.in_dll(dll, 'right')
        bottom = c_long.in_dll(dll, 'bottom')
        rect = RECT(left, top, right, bottom)
        PointInRect = dll.PointInRect
        PointInRect.argtypes = [POINTER(RECT), POINT]
        self.assertEqual(1, PointInRect(byref(rect), pt))

        ReturnRect = dll.ReturnRect
        ReturnRect.argtypes = [c_int, RECT, POINTER(RECT), POINT, RECT,
                               POINTER(RECT), POINT, RECT]
        ReturnRect.restype = RECT
        for i in range(4):
            ret = ReturnRect(i, rect, pointer(rect), pt, rect,
                         byref(rect), pt, rect)
            # the c function will check and modify ret if something is
            # passed in improperly
            self.assertEqual(ret.left, left.value)
            self.assertEqual(ret.right, right.value)
            self.assertEqual(ret.top, top.value)
            self.assertEqual(ret.bottom, bottom.value)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[RECT]

def test_struct_struct(self):
        # nested structures with different byteorders

        # create nested structures with given byteorders and set memory to data

        for nested, data in (
            (BigEndianStructure, b'\0\0\0\1\0\0\0\2'),
            (LittleEndianStructure, b'\1\0\0\0\2\0\0\0'),
        ):
            for parent in (
                BigEndianStructure,
                LittleEndianStructure,
                Structure,
            ):
                class NestedStructure(nested):
                    _fields_ = [("x", c_uint32),
                                ("y", c_uint32)]

                class TestStructure(parent):
                    _fields_ = [("point", NestedStructure)]

                self.assertEqual(len(data), sizeof(TestStructure))
                ptr = POINTER(TestStructure)
                s = cast(data, ptr)[0]
                del ctypes._pointer_type_cache[TestStructure]
                self.assertEqual(s.point.x, 1)
                self.assertEqual(s.point.y, 2)

def test_frozentable(self):
        # Python exports a PyImport_FrozenModules symbol. This is a
        # pointer to an array of struct _frozen entries.  The end of the
        # array is marked by an entry containing a NULL name and zero
        # size.

        # In standard Python, this table contains a __hello__
        # module, and a __phello__ package containing a spam
        # module.
        class struct_frozen(Structure):
            _fields_ = [("name", c_char_p),
                        ("code", POINTER(c_ubyte)),
                        ("size", c_int)]
        FrozenTable = POINTER(struct_frozen)

        ft = FrozenTable.in_dll(pythonapi, "PyImport_FrozenModules")
        # ft is a pointer to the struct_frozen entries:
        items = []
        for entry in ft:
            # This is dangerous. We *can* iterate over a pointer, but
            # the loop will not terminate (maybe with an access
            # violation;-) because the pointer instance has no size.
            if entry.name is None:
                break
            items.append((entry.name, entry.size))

        expected = [("__hello__", 104),
                    ("__phello__", -104),
                    ("__phello__.spam", 104)]
        self.assertEqual(items, expected)

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[struct_frozen]

def test_incomplete_example(self):
        lpcell = POINTER("cell")
        class cell(Structure):
            _fields_ = [("name", c_char_p),
                        ("next", lpcell)]

        SetPointerType(lpcell, cell)

        c1 = cell()
        c1.name = "foo"
        c2 = cell()
        c2.name = "bar"

        c1.next = pointer(c2)
        c2.next = pointer(c1)

        p = c1

        result = []
        for i in range(8):
            result.append(p.name)
            p = p.next[0]
        self.assertEqual(result, ["foo", "bar"] * 4)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[cell]

################################################################

def test_struct_struct(self):
        # nested structures with different byteorders

        # create nested structures with given byteorders and set memory to data

        for nested, data in (
            (BigEndianStructure, b'\0\0\0\1\0\0\0\2'),
            (LittleEndianStructure, b'\1\0\0\0\2\0\0\0'),
        ):
            for parent in (
                BigEndianStructure,
                LittleEndianStructure,
                Structure,
            ):
                class NestedStructure(nested):
                    _fields_ = [("x", c_uint32),
                                ("y", c_uint32)]

                class TestStructure(parent):
                    _fields_ = [("point", NestedStructure)]

                self.assertEqual(len(data), sizeof(TestStructure))
                ptr = POINTER(TestStructure)
                s = cast(data, ptr)[0]
                del ctypes._pointer_type_cache[TestStructure]
                self.assertEqual(s.point.x, 1)
                self.assertEqual(s.point.y, 2)

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
        from ctypes import _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
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[id(P)]

def test_incomplete_example(self):
        lpcell = POINTER("cell")
        class cell(Structure):
            _fields_ = [("name", c_char_p),
                        ("next", lpcell)]

        SetPointerType(lpcell, cell)

        c1 = cell()
        c1.name = b"foo"
        c2 = cell()
        c2.name = b"bar"

        c1.next = pointer(c2)
        c2.next = pointer(c1)

        p = c1

        result = []
        for i in range(8):
            result.append(p.name)
            p = p.next[0]
        self.assertEqual(result, [b"foo", b"bar"] * 4)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[cell]

################################################################

def test_struct_by_value(self):
        class POINT(Structure):
            _fields_ = [("x", c_long),
                        ("y", c_long)]

        class RECT(Structure):
            _fields_ = [("left", c_long),
                        ("top", c_long),
                        ("right", c_long),
                        ("bottom", c_long)]

        dll = CDLL(_ctypes_test.__file__)

        pt = POINT(15, 25)
        left = c_long.in_dll(dll, 'left')
        top = c_long.in_dll(dll, 'top')
        right = c_long.in_dll(dll, 'right')
        bottom = c_long.in_dll(dll, 'bottom')
        rect = RECT(left, top, right, bottom)
        PointInRect = dll.PointInRect
        PointInRect.argtypes = [POINTER(RECT), POINT]
        self.assertEqual(1, PointInRect(byref(rect), pt))

        ReturnRect = dll.ReturnRect
        ReturnRect.argtypes = [c_int, RECT, POINTER(RECT), POINT, RECT,
                               POINTER(RECT), POINT, RECT]
        ReturnRect.restype = RECT
        for i in range(4):
            ret = ReturnRect(i, rect, pointer(rect), pt, rect,
                         byref(rect), pt, rect)
            # the c function will check and modify ret if something is
            # passed in improperly
            self.assertEqual(ret.left, left.value)
            self.assertEqual(ret.right, right.value)
            self.assertEqual(ret.top, top.value)
            self.assertEqual(ret.bottom, bottom.value)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[RECT]

def test_struct_struct(self):
        # nested structures with different byteorders

        # create nested structures with given byteorders and set memory to data

        for nested, data in (
            (BigEndianStructure, b'\0\0\0\1\0\0\0\2'),
            (LittleEndianStructure, b'\1\0\0\0\2\0\0\0'),
        ):
            for parent in (
                BigEndianStructure,
                LittleEndianStructure,
                Structure,
            ):
                class NestedStructure(nested):
                    _fields_ = [("x", c_uint32),
                                ("y", c_uint32)]

                class TestStructure(parent):
                    _fields_ = [("point", NestedStructure)]

                self.assertEqual(len(data), sizeof(TestStructure))
                ptr = POINTER(TestStructure)
                s = cast(data, ptr)[0]
                del ctypes._pointer_type_cache[TestStructure]
                self.assertEqual(s.point.x, 1)
                self.assertEqual(s.point.y, 2)

def test_frozentable(self):
            # Python exports a PyImport_FrozenModules symbol. This is a
            # pointer to an array of struct _frozen entries.  The end of the
            # array is marked by an entry containing a NULL name and zero
            # size.

            # In standard Python, this table contains a __hello__
            # module, and a __phello__ package containing a spam
            # module.
            class struct_frozen(Structure):
                _fields_ = [("name", c_char_p),
                            ("code", POINTER(c_ubyte)),
                            ("size", c_int)]
            FrozenTable = POINTER(struct_frozen)

            ft = FrozenTable.in_dll(pydll, "PyImport_FrozenModules")
            # ft is a pointer to the struct_frozen entries:
            items = []
            for entry in ft:
                # This is dangerous. We *can* iterate over a pointer, but
                # the loop will not terminate (maybe with an access
                # violation;-) because the pointer instance has no size.
                if entry.name is None:
                    break
                items.append((entry.name, entry.size))
            import sys
            if sys.version_info[:2] >= (2, 3):
                expected = [("__hello__", 104), ("__phello__", -104), ("__phello__.spam", 104)]
            else:
                expected = [("__hello__", 100), ("__phello__", -100), ("__phello__.spam", 100)]
            self.assertEqual(items, expected)

            from ctypes import _pointer_type_cache
            del _pointer_type_cache[struct_frozen]

def test_incomplete_example(self):
        lpcell = POINTER("cell")
        class cell(Structure):
            _fields_ = [("name", c_char_p),
                        ("next", lpcell)]

        SetPointerType(lpcell, cell)

        c1 = cell()
        c1.name = "foo"
        c2 = cell()
        c2.name = "bar"

        c1.next = pointer(c2)
        c2.next = pointer(c1)

        p = c1

        result = []
        for i in range(8):
            result.append(p.name)
            p = p.next[0]
        self.assertEqual(result, ["foo", "bar"] * 4)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[cell]

################################################################

def test_struct_struct(self):
        # nested structures with different byteorders

        # create nested structures with given byteorders and set memory to data

        for nested, data in (
            (BigEndianStructure, b'\0\0\0\1\0\0\0\2'),
            (LittleEndianStructure, b'\1\0\0\0\2\0\0\0'),
        ):
            for parent in (
                BigEndianStructure,
                LittleEndianStructure,
                Structure,
            ):
                class NestedStructure(nested):
                    _fields_ = [("x", c_uint32),
                                ("y", c_uint32)]

                class TestStructure(parent):
                    _fields_ = [("point", NestedStructure)]

                self.assertEqual(len(data), sizeof(TestStructure))
                ptr = POINTER(TestStructure)
                s = cast(data, ptr)[0]
                del ctypes._pointer_type_cache[TestStructure]
                self.assertEqual(s.point.x, 1)
                self.assertEqual(s.point.y, 2)

def test_incomplete_example(self):
        lpcell = POINTER("cell")
        class cell(Structure):
            _fields_ = [("name", c_char_p),
                        ("next", lpcell)]

        SetPointerType(lpcell, cell)

        c1 = cell()
        c1.name = b"foo"
        c2 = cell()
        c2.name = b"bar"

        c1.next = pointer(c2)
        c2.next = pointer(c1)

        p = c1

        result = []
        for i in range(8):
            result.append(p.name)
            p = p.next[0]
        self.assertEqual(result, [b"foo", b"bar"] * 4)

        # to not leak references, we must clean _pointer_type_cache
        from ctypes import _pointer_type_cache
        del _pointer_type_cache[cell]

################################################################

def test_frozentable(self):
        # Python exports a PyImport_FrozenModules symbol. This is a
        # pointer to an array of struct _frozen entries.  The end of the
        # array is marked by an entry containing a NULL name and zero
        # size.

        # In standard Python, this table contains a __hello__
        # module, and a __phello__ package containing a spam
        # module.
        class struct_frozen(Structure):
            _fields_ = [("name", c_char_p),
                        ("code", POINTER(c_ubyte)),
                        ("size", c_int)]
        FrozenTable = POINTER(struct_frozen)

        ft = FrozenTable.in_dll(pythonapi, "PyImport_FrozenModules")
        # ft is a pointer to the struct_frozen entries:
        items = []
        # _frozen_importlib changes size whenever importlib._bootstrap
        # changes, so it gets a special case.  We should make sure it's
        # found, but don't worry about its size too much.
        _fzn_implib_seen = False
        for entry in ft:
            # This is dangerous. We *can* iterate over a pointer, but
            # the loop will not terminate (maybe with an access
            # violation;-) because the pointer instance has no size.
            if entry.name is None:
                break

            if entry.name == b'_frozen_importlib':
                _fzn_implib_seen = True
                self.assertTrue(entry.size,
                    "_frozen_importlib was reported as having no size")
                continue
            items.append((entry.name, entry.size))

        expected = [(b"__hello__", 161),
                    (b"__phello__", -161),
                    (b"__phello__.spam", 161),
                    ]
        self.assertEqual(items, expected)

        self.assertTrue(_fzn_implib_seen,
            "_frozen_importlib wasn't found in PyImport_FrozenModules")

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[struct_frozen]

def test_frozentable(self):
        # Python exports a PyImport_FrozenModules symbol. This is a
        # pointer to an array of struct _frozen entries.  The end of the
        # array is marked by an entry containing a NULL name and zero
        # size.

        # In standard Python, this table contains a __hello__
        # module, and a __phello__ package containing a spam
        # module.
        class struct_frozen(Structure):
            _fields_ = [("name", c_char_p),
                        ("code", POINTER(c_ubyte)),
                        ("size", c_int)]
        FrozenTable = POINTER(struct_frozen)

        ft = FrozenTable.in_dll(pythonapi, "PyImport_FrozenModules")
        # ft is a pointer to the struct_frozen entries:
        items = []
        # _frozen_importlib changes size whenever importlib._bootstrap
        # changes, so it gets a special case.  We should make sure it's
        # found, but don't worry about its size too much.
        _fzn_implib_seen = False
        for entry in ft:
            # This is dangerous. We *can* iterate over a pointer, but
            # the loop will not terminate (maybe with an access
            # violation;-) because the pointer instance has no size.
            if entry.name is None:
                break

            if entry.name == b'_frozen_importlib':
                _fzn_implib_seen = True
                self.assertTrue(entry.size,
                    "_frozen_importlib was reported as having no size")
                continue
            items.append((entry.name, entry.size))

        expected = [(b"__hello__", 161),
                    (b"__phello__", -161),
                    (b"__phello__.spam", 161),
                    ]
        self.assertEqual(items, expected)

        self.assertTrue(_fzn_implib_seen,
            "_frozen_importlib wasn't found in PyImport_FrozenModules")

        from ctypes import _pointer_type_cache
        del _pointer_type_cache[struct_frozen]