[ctypes-commit] ctypes/source callproc.c,1.114,1.115

[Thomas H. <th...@us...>]

Update of /cvsroot/ctypes/ctypes/source
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv18585

Modified Files:
	callproc.c 
Log Message:
Define a new protocol for function's restype.  If it is a ctypes'
type, it is handled in the usual way.  But if it additionally has an
_check_retval_ attribute, this is called with the result, and the
return value of this call is the functions return value.

This allows to define HRESULT as a ctypes' type, because it can check
for failure in it's _check_retval_ static method, and raise a
WindowsError.

Although HRESULT is defined in python code (since it is derived from
c_long), the _check_retval_ method is implemented in C - in this way
the traceback won't include the _check_retval_ method definition itself.


Index: callproc.c
===================================================================
RCS file: /cvsroot/ctypes/ctypes/source/callproc.c,v
retrieving revision 1.114
retrieving revision 1.115
diff -C2 -d -r1.114 -r1.115
*** callproc.c	28 Oct 2004 17:45:50 -0000	1.114
--- callproc.c	29 Oct 2004 18:46:38 -0000	1.115
***************
*** 768,772 ****
  		   Is there another way?
  		 */
! 		PyObject *retval;
  		char c;
  		short s;
--- 768,772 ----
  		   Is there another way?
  		 */
! 		PyObject *retval, *checker;
  		char c;
  		short s;
***************
*** 798,802 ****
  			break;
  		}
! 		return retval;
  	}
  	if (PyCallable_Check(restype))
--- 798,812 ----
  			break;
  		}
! 		if (retval == NULL)
! 			return NULL;
! 		checker = PyObject_GetAttrString(restype, "_check_retval_");
! 		if (checker == NULL) {
! 			PyErr_Clear();
! 			return retval;
! 		} else {
! 			PyObject *v = PyObject_CallFunctionObjArgs(checker, retval, NULL);
! 			Py_DECREF(retval);
! 			return v;
! 		}
  	}
  	if (PyCallable_Check(restype))
***************
*** 1418,1421 ****
--- 1428,1432 ----
  #endif
  
+ 
  PyMethodDef module_methods[] = {
  	{"string_at", string_at, METH_VARARGS, string_at_doc},
***************
*** 1433,1437 ****
  	{"FreeLibrary", free_library, METH_VARARGS, free_library_doc},
  	{"call_commethod", call_commethod, METH_VARARGS },
! 	{"HRESULT", check_hresult, METH_VARARGS},
  #else
  	{"dlopen", py_dl_open, METH_VARARGS, "dlopen a library"},
--- 1444,1448 ----
  	{"FreeLibrary", free_library, METH_VARARGS, free_library_doc},
  	{"call_commethod", call_commethod, METH_VARARGS },
! 	{"_check_HRESULT", check_hresult, METH_VARARGS},
  #else
  	{"dlopen", py_dl_open, METH_VARARGS, "dlopen a library"},