/*

* Copyright (c) 2007 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_NATFWASYNCCALLBACK_H

#define C_NATFWASYNCCALLBACK_H

// INCLUDES

#include <e32base.h>

#include "natfwcallbackinfo.h"

// CLASS DECLARATION

/**

 * CNatFwAsyncCallback is an active object used to guarantee that when the

 * function calls to the MNATFWConnectivityObserver are made, the upper layer

 * can delete any plugin related object it owns.

 */

NONSHARABLE_CLASS( CNatFwAsyncCallback ) : public CActive

    {

public: // Constructor and destructor

    /**

     * Two-phased constructor.

     */

    static CNatFwAsyncCallback* NewL();

    /**

     * Frees the resources of CNatFwAsyncCallback. Any issued callback

     * request that have not yet been executed, are discarded.

     *

     * @since   s60 3.2

     */

    ~CNatFwAsyncCallback();

public: // New functions

    /**

     * Orders a specified callback function to be called, and provides all

     * necessary parameters.

     *

     * @since   s60 3.2

     * @param   aController Event registration controller

     * @param   aFunction   Identifies the function of

     *                      MNATFWConnectivityObserver to use

     * @param   aSessionId  Session ID

     * @param   aStreamId   Stream ID

     * @param   aErrorCode  Error reason

     * @return  void

     */

    void MakeCallbackL( MNATFWRegistrationController& aController,

                        CNatFwCallbackInfo::TFunction aFunction,

                        TUint aSessionId,

                        TUint aStreamId,

                        TInt aErrorCode,

                        TAny* aEventData );

    /**

     * Removes all pending callbacks, which have the specified

     * stream ID as a parameter.

     *

     * @since   s60 3.2

     * @param   aStreamId

     * @return  void

     */

    void CancelCallback( TUint aStreamId );

protected: // From CActive

    void DoCancel();

    void RunL();

    TInt RunError( TInt aError );

private: // Constructors

    CNatFwAsyncCallback();

private: // New functions, for internal use

    /**

     * Starts waiting for MakeCallbackL events.

     *

     * @since   s60 3.2

     * @return  void

     */

    void WaitForRequestsL();

    /**

     * Wakes system up.

     *

     * @since   s60 3.2

     * @return  void

     */

    void Wakeup();

    /**

     * Calls the oldest callback entry, if any.

     *

     * @since   s60 3.2

     * @return  void

     */

    void ExecuteFirstCallback();

private: // Data

    /**

     * Callback requests that have not yet been executed

     */

    TSglQue<CNatFwCallbackInfo> iPendingCallbacks;

    };

#endif // C_NATFWASYNCCALLBACK_H