--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/natfw/natfwstunturnclient/inc/casynccallback.h	Tue Feb 02 01:04:58 2010 +0200
@@ -0,0 +1,130 @@
+/*
+* Copyright (c) 2005 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:    
+*
+*/
+
+
+
+
+#ifndef C_ASYNCCALLBACK_H
+#define C_ASYNCCALLBACK_H
+
+// INCLUDES
+#include <e32base.h>
+#include "tstuncallbackinfo.h"
+
+// FORWARD DECLARATIONS
+class MSTUNClientObserver;
+class CBinding;
+
+// CLASS DECLARATION
+/*
+ * CAsyncCallback is an active object used to guarantee that when the function
+ * calls to the MSTUNClientObserver are made, the upper layer can delete any
+ * STUN client related object it owns.
+ */
+class CAsyncCallback : public CActive
+    {
+public: // Constructor and destructor
+
+    /**
+     * Creates a new instance of CAsyncCallback.
+     *
+     * @param aObserver Observer implementing the callback functions
+     * @return value New CAsyncCallback object. Ownership is transferred.
+     */
+    static CAsyncCallback* NewL( MSTUNClientObserver& aObserver );
+
+    /**     
+     * Frees the resources of CAsyncCallback. Any issued callback request that
+     * have not yet been executed, are discarded.
+     */
+    ~CAsyncCallback();
+
+public: // From CActive
+
+    void DoCancel();
+
+    void RunL();
+
+    TInt RunError( TInt aError );
+
+public: // New functions
+
+    /**
+     * Orders a specified callback function to be called, and provides all
+     * necessary parameters.
+     *     
+     * @param aFunction Identifies the function of MSTUNClientObserver to use
+     * @param aBinding STUN binding
+     * @param aErrorCode Error reason
+     * @param aClient STUN client     
+     */
+    void MakeCallbackL( TSTUNCallbackInfo::TFunction aFunction,
+                        const CBinding* aBinding,
+                        TInt aErrorCode = KErrNone,
+                        const CSTUNClient* aClient = NULL );
+
+    /**
+     * Removes all pending callbacks, which have the specified binding as a
+     * parameter.
+     *
+     * @param aBinding STUN binding     
+     */
+    void CancelCallback( const CBinding& aBinding );
+
+    /**
+     * Calls the oldest callback entry, if any.
+     *
+     * @param aBinding STUN binding     
+     */
+    void ExecuteFirstCallback();
+
+private: // Constructors
+
+    CAsyncCallback();
+
+    CAsyncCallback( MSTUNClientObserver& aObserver );
+
+    CAsyncCallback( const CAsyncCallback& aAsyncCallback );
+
+private: // New functions, for internal use
+
+    /**
+     * Starts waiting for MakeCallbackL events.
+     */
+    void WaitForRequests();
+
+    void Wakeup();
+
+private: // Data
+
+    // Implements the callback functions
+    MSTUNClientObserver& iObserver;
+
+    // Callback requests that have not yet been executed
+    TSglQue<TSTUNCallbackInfo> iPendingCallbacks;
+
+private: // For testing purposes
+
+#ifdef TEST_EUNIT
+    friend class CAsyncCallbackTest;
+    friend class CSTUNClientTest;
+#endif
+    };
+
+#endif // end of C_ASYNCCALLBACK_H
+
+// End of File