bpo-28129: fix ctypes crashes (#386)

* init commit, with initial tests for from_param and fields __set__ and __get__, and some additions to from_buffer and from_buffer_copy

* added the rest of tests and patches. probably only a first draft.

* removed trailing spaces

* replace ctype with ctypes in error messages

* change back from ctypes instance to ctype instance

5 files changed, 53 insertions, 0 deletions

diff --git a/Lib/ctypes/test/test_frombuffer.py b/Lib/ctypes/test/test_frombuffer.py
index 7ab38f1..55c2443 100644
--- a/Lib/ctypes/test/test_frombuffer.py
+++ b/Lib/ctypes/test/test_frombuffer.py
@@ -121,12 +121,21 @@ class Test(unittest.TestCase):
             (c_int * 1).from_buffer_copy(a, 16 * sizeof(c_int))
 
     def test_abstract(self):
+        from ctypes import _Pointer, _SimpleCData, _CFuncPtr
+
         self.assertRaises(TypeError, Array.from_buffer, bytearray(10))
         self.assertRaises(TypeError, Structure.from_buffer, bytearray(10))
         self.assertRaises(TypeError, Union.from_buffer, bytearray(10))
+        self.assertRaises(TypeError, _CFuncPtr.from_buffer, bytearray(10))
+        self.assertRaises(TypeError, _Pointer.from_buffer, bytearray(10))
+        self.assertRaises(TypeError, _SimpleCData.from_buffer, bytearray(10))
+
         self.assertRaises(TypeError, Array.from_buffer_copy, b"123")
         self.assertRaises(TypeError, Structure.from_buffer_copy, b"123")
         self.assertRaises(TypeError, Union.from_buffer_copy, b"123")
+        self.assertRaises(TypeError, _CFuncPtr.from_buffer_copy, b"123")
+        self.assertRaises(TypeError, _Pointer.from_buffer_copy, b"123")
+        self.assertRaises(TypeError, _SimpleCData.from_buffer_copy, b"123")
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/Lib/ctypes/test/test_funcptr.py b/Lib/ctypes/test/test_funcptr.py
index f34734b..e0b9b54 100644
--- a/Lib/ctypes/test/test_funcptr.py
+++ b/Lib/ctypes/test/test_funcptr.py
@@ -123,5 +123,10 @@ class CFuncPtrTestCase(unittest.TestCase):
         self.assertEqual(strtok(None, b"\n"), b"c")
         self.assertEqual(strtok(None, b"\n"), None)
 
+    def test_abstract(self):
+        from ctypes import _CFuncPtr
+
+        self.assertRaises(TypeError, _CFuncPtr, 13, "name", 42, "iid")
+
 if __name__ == '__main__':
     unittest.main()
diff --git a/Lib/ctypes/test/test_parameters.py b/Lib/ctypes/test/test_parameters.py
index 363f586..4eaa15a 100644
--- a/Lib/ctypes/test/test_parameters.py
+++ b/Lib/ctypes/test/test_parameters.py
@@ -169,6 +169,16 @@ class SimpleTypesTestCase(unittest.TestCase):
         # ArgumentError: argument 1: ValueError: 99
         self.assertRaises(ArgumentError, func, 99)
 
+    def test_abstract(self):
+        from ctypes import (Array, Structure, Union, _Pointer,
+                            _SimpleCData, _CFuncPtr)
+
+        self.assertRaises(TypeError, Array.from_param, 42)
+        self.assertRaises(TypeError, Structure.from_param, 42)
+        self.assertRaises(TypeError, Union.from_param, 42)
+        self.assertRaises(TypeError, _CFuncPtr.from_param, 42)
+        self.assertRaises(TypeError, _Pointer.from_param, 42)
+        self.assertRaises(TypeError, _SimpleCData.from_param, 42)
 
 ################################################################
 
diff --git a/Lib/ctypes/test/test_pointers.py b/Lib/ctypes/test/test_pointers.py
index 751f85f..e975158 100644
--- a/Lib/ctypes/test/test_pointers.py
+++ b/Lib/ctypes/test/test_pointers.py
@@ -213,6 +213,11 @@ class PointersTestCase(unittest.TestCase):
         from ctypes import _pointer_type_cache
         del _pointer_type_cache[id(P)]
 
+    def test_abstract(self):
+        from ctypes import _Pointer
+
+        self.assertRaises(TypeError, _Pointer.set_type, 42)
+
 
 if __name__ == '__main__':
     unittest.main()
diff --git a/Lib/ctypes/test/test_struct_fields.py b/Lib/ctypes/test/test_struct_fields.py
index 22eb3b0..8045cc8 100644
--- a/Lib/ctypes/test/test_struct_fields.py
+++ b/Lib/ctypes/test/test_struct_fields.py
@@ -46,5 +46,29 @@ class StructFieldsTestCase(unittest.TestCase):
         Y._fields_ = []
         self.assertRaises(AttributeError, setattr, X, "_fields_", [])
 
+    # __set__ and __get__ should raise a TypeError in case their self
+    # argument is not a ctype instance.
+    def test___set__(self):
+        class MyCStruct(Structure):
+            _fields_ = (("field", c_int),)
+        self.assertRaises(TypeError,
+                          MyCStruct.field.__set__, 'wrong type self', 42)
+
+        class MyCUnion(Union):
+            _fields_ = (("field", c_int),)
+        self.assertRaises(TypeError,
+                          MyCUnion.field.__set__, 'wrong type self', 42)
+
+    def test___get__(self):
+        class MyCStruct(Structure):
+            _fields_ = (("field", c_int),)
+        self.assertRaises(TypeError,
+                          MyCStruct.field.__get__, 'wrong type self', 42)
+
+        class MyCUnion(Union):
+            _fields_ = (("field", c_int),)
+        self.assertRaises(TypeError,
+                          MyCUnion.field.__get__, 'wrong type self', 42)
+
 if __name__ == "__main__":
     unittest.main()