Merge pull request #16 from alxf/issue-#15

Issue #15: Fix returned pointer with caca types.

python/caca/canvas.py

@@ -21,12 +21,16 @@ from caca import _lib, utf8_to_utf32, utf32_to_utf8
 from caca import _PYTHON3, _str_to_bytes, _bytes_to_str
 from caca.font import _Font
 
+
+class _CanvasStruct(ctypes.Structure):
+    pass
+
 class _Canvas(object):
     """ Model for Canvas objects.
     """
 
     def __init__(self):
-        self._cv = 0
+        self._cv = None
 
     def from_param(self):
         """ Required by ctypes module to call object as parameter of
@@ -38,7 +42,7 @@ class _Canvas(object):
         return "<CacaCanvas %dx%d>" % (self.get_width(), self.get_height())
 
     def __del__(self):
-        if self._cv > 0 and _lib is not None:
+        if self._cv and _lib is not None:
             self._free()
 
     def _free(self):
@@ -61,6 +65,7 @@ class Canvas(_Canvas):
             pointer -- pointer to libcaca canvas
         """
         _lib.caca_create_canvas.argtypes = [ctypes.c_int, ctypes.c_int]
+        _lib.caca_create_canvas.restype = ctypes.POINTER(_CanvasStruct)
 
         if pointer is None:
             try:

python/caca/display.py

@@ -19,6 +19,11 @@ import ctypes
 from caca import _lib, _PYTHON3, _str_to_bytes
 from caca.canvas import _Canvas, Canvas
 
+
+class _DisplayStruct(ctypes.Structure):
+    pass
+
+
 class _Display(object):
     """ Model for Display objects.
     """
@@ -32,7 +37,7 @@ class _Display(object):
         return "<CacaDisplay>"
 
     def __del__(self):
-        if self._dp > 0 and _lib is not None:
+        if self._dp and _lib is not None:
             self._free()
 
     def _free(self):
@@ -57,11 +62,15 @@ class Display(_Display):
 
         if driver is None:
             _lib.caca_create_display.argtypes = [_Canvas]
+            _lib.caca_create_display.restype = ctypes.POINTER(_DisplayStruct)
             self._dp = _lib.caca_create_display(cv)
         else:
             _lib.caca_create_display_with_driver.argtypes = [
                 _Canvas, ctypes.c_char_p
             ]
+            _lib.caca_create_display_with_driver.restype = ctypes.POINTER(
+                    _DisplayStruct
+                )
             if _PYTHON3 and isinstance(driver, str):
                 driver = _str_to_bytes(driver)
 
@@ -197,9 +206,11 @@ class Display(_Display):
 
         return _lib.caca_get_mouse_y(self)
 
+
 class DisplayError(Exception):
     pass
 
+
 class Event(ctypes.Structure):
     """ Object to store libcaca event.
     """

python/caca/dither.py

@@ -19,11 +19,15 @@ import ctypes
 from caca import _lib
 from caca.canvas import _Canvas
 
+
+class _DitherStruct(ctypes.Structure):
+    pass
+
 class _Dither(object):
     """ Model for Dither object.
     """
     def __init__(self):
-        self._dither = 0
+        self._dither = None
 
     def from_param(self):
         """ Required by ctypes module to call object as parameter of
@@ -32,7 +36,7 @@ class _Dither(object):
         return self._dither
 
     def __del__(self):
-        if self._dither > 0:
+        if self._dither:
             self._free()
 
     def __str__(self):
@@ -66,6 +70,7 @@ class Dither(_Dither):
             ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int,
             ctypes.c_uint, ctypes.c_uint, ctypes.c_uint, ctypes.c_uint,
         ]
+        _lib.caca_create_dither.restype = ctypes.POINTER(_DitherStruct)
 
         self._dither = _lib.caca_create_dither(bpp, width, height, pitch,
                                                rmask, gmask, bmask, amask)

python/caca/font.py

@@ -19,11 +19,15 @@ import errno
 
 from caca import _lib, _PYTHON3, _str_to_bytes
 
+
+class _FontStruct(ctypes.Structure):
+    pass
+
 class _Font(object):
     """ Model for Font object.
     """
     def __init__(self):
-        self._font = 0
+        self._font = None
 
     def from_param(self):
         """ Required by ctypes module to call object as parameter of
@@ -33,7 +37,7 @@ class _Font(object):
 
     def __del__(self):
         if hasattr(self, "_font"):
-            if self._font > 0:
+            if self._font:
                 self._free()
 
     def __str__(self):
@@ -62,7 +66,7 @@ class Font(_Font):
         else:
             raise FontError("Unsupported method")
 
-        _lib.caca_load_font.restype = ctypes.c_int
+        _lib.caca_load_font.restype = ctypes.POINTER(_FontStruct)
 
         if _PYTHON3:
             font = _str_to_bytes(font)