/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the Python XPCOM language bindings.
*
* The Initial Developer of the Original Code is
* ActiveState Tool Corp.
* Portions created by the Initial Developer are Copyright (C) 2000
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Mark Hammond <mhammond@skippinet.com.au> (original author)
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
// PyXPTStub - the stub for implementing interfaces.
//
// This code is part of the XPCOM extensions for Python.
//
// Written May 2000 by Mark Hammond.
//
// Based heavily on the Python COM support, which is
// (c) Mark Hammond and Greg Stein.
//
// (c) 2000, ActiveState corp.
#include "PyXPCOM_std.h"
#include <nsIInterfaceInfoManager.h>
PyXPCOM_XPTStub::PyXPCOM_XPTStub(PyObject *instance, const nsIID &iid)
: PyG_Base(instance, iid)
{
if (NS_FAILED(InitStub(iid)))
NS_ERROR("InitStub must not fail!");
}
void *PyXPCOM_XPTStub::ThisAsIID(const nsIID &iid)
{
// Not quite clear who should get nsISupports - I would
// expect our PyG_Base, but Java gives it the stub.
if (iid.Equals(NS_GET_IID(nsISupports)) || iid.Equals(m_iid)) {
return mXPTCStub;
}
// else
return PyG_Base::ThisAsIID(iid);
}
// call this method and return result
NS_IMETHODIMP
PyXPCOM_XPTStub::CallMethod(PRUint16 methodIndex,
const XPTMethodDescriptor* info,
nsXPTCMiniVariant* params)
{
nsresult rc = NS_ERROR_FAILURE;
NS_PRECONDITION(info, "NULL methodinfo pointer");
NS_PRECONDITION(params, "NULL variant pointer");
CEnterLeavePython _celp;
PyObject *obParams = NULL;
PyObject *result = NULL;
PyObject *obThisObject = NULL;
PyObject *obMI = PyObject_FromXPTMethodDescriptor(info);
PyXPCOM_GatewayVariantHelper arg_helper(this, methodIndex, info, params);
if (obMI==NULL)
goto done;
// base object is passed raw.
obThisObject = PyObject_FromNSInterface((nsISupports *)ThisAsIID(m_iid),
m_iid, PR_FALSE);
obParams = arg_helper.MakePyArgs();
if (obParams==NULL)
goto done;
result = PyObject_CallMethod(m_pPyObject,
"_CallMethod_",
"OiOO",
obThisObject,
(int)methodIndex,
obMI,
obParams);
if (result!=NULL) {
rc = arg_helper.ProcessPythonResult(result);
// Use an xor to check failure && pyerr, or !failure && !pyerr.
NS_ABORT_IF_FALSE( ((NS_FAILED(rc)!=0)^(PyErr_Occurred()!=0)) == 0, "We must have failure with a Python error, or success without a Python error.");
}
done:
if (PyErr_Occurred()) {
// The error handling - fairly involved, but worth it as
// good error reporting is critical for users to know WTF
// is going on - especially with TypeErrors etc in their
// return values (ie, after the Python code has successfully
// exited, but we encountered errors unpacking the
// result values for the COM caller - there is literally no
// way to catch these exceptions from Python code, as their
// is no Python function on the call-stack)
// First line of attack in an error is to call-back on the policy.
// If the callback of the error handler succeeds and returns an
// integer (for the nsresult), we take no further action.
// If this callback fails, we log _2_ exceptions - the error handler
// error, and the original error.
PRBool bProcessMainError = PR_TRUE; // set to false if our exception handler does its thing!
PyObject *exc_typ, *exc_val, *exc_tb;
PyErr_Fetch(&exc_typ, &exc_val, &exc_tb);
PyErr_NormalizeException( &exc_typ, &exc_val, &exc_tb);
PyObject *err_result = PyObject_CallMethod(m_pPyObject,
"_CallMethodException_",
"OiOO(OOO)",
obThisObject,
(int)methodIndex,
obMI,
obParams,
exc_typ ? exc_typ : Py_None, // should never be NULL, but defensive programming...
exc_val ? exc_val : Py_None, // may well be NULL.
exc_tb ? exc_tb : Py_None); // may well be NULL.
if (err_result == NULL) {
PyXPCOM_LogError("The exception handler _CallMethodException_ failed!\n");
} else if (err_result == Py_None) {
// The exception handler has chosen not to do anything with
// this error, so we still need to print it!
;
} else if (PyInt_Check(err_result)) {
// The exception handler has given us the nresult.
rc = PyInt_AsLong(err_result);
bProcessMainError = PR_FALSE;
} else {
// The exception handler succeeded, but returned other than
// int or None.
PyXPCOM_LogError("The _CallMethodException_ handler returned object of type '%s' - None or an integer expected\n", err_result->ob_type->tp_name);
}
Py_XDECREF(err_result);
PyErr_Restore(exc_typ, exc_val, exc_tb);
if (bProcessMainError) {
PyXPCOM_LogError("The function '%s' failed\n", info->name);
rc = PyXPCOM_SetCOMErrorFromPyException();
}
// else everything is already setup,
// just clear the Python error state.
PyErr_Clear();
}
Py_XDECREF(obMI);
Py_XDECREF(obParams);
Py_XDECREF(obThisObject);
Py_XDECREF(result);
return rc;
}