/*

* Copyright (c) 2002-2005 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:  Header file for Iscqueue

*

*/

#ifndef DISCQUEUE_H

#define DISCQUEUE_H

//  INCLUDES

#include <kernel.h>

// CONSTANTS

// MACROS

// DATA TYPES

// FUNCTION PROTOTYPES

// FORWARD DECLARATIONS

// CLASS DECLARATION

/**

*  Generic FIFO-type class

*

*  @lib IscDriver.LIB

*  @since 2.8

*/

class DIscQueue

    {

    public:  // Constructors and destructor

        DIscQueue();

        /**

        * C++ default constructor.

        */

        IMPORT_C DIscQueue( TUint32** aQueue, TUint16 Size );

        /**

        * Destructor.

        */

        IMPORT_C virtual ~DIscQueue();

        /**

        * Function to add element to queue

		* @since 2.8

        * @param TAny* pointer to frame

        * @return TInt KErrNone / KErrNoMemory

        */

        IMPORT_C TInt Add( TAny* );

        /**

        * Removes first element from the queue

		* @since 2.8

        * @return TAny* pointer to frame

        */

        IMPORT_C TAny* RemoveFirst();

        /**

        * Fetches first element from the queue

		* @since 2.8

        * @return TAny* pointer to frame

        */

        IMPORT_C TAny* GetFirst();

        /**

        * Deletes first element from the queue

		* @since 2.8

        * @return void 

        */

        IMPORT_C void DeleteFirst(); 

        /**

        * Checks if queue is empty

		* @since 2.8

        * @return TBool ETrue if empty, otherwise EFalse

        */

        IMPORT_C TBool Empty();

        /**

        * Gets length of next frame in queue

		* @since 2.8

        * @return TUint16 

        */

        IMPORT_C TUint16 NextBufferLength();

        /**

        * Inline function to tell the amount of elements in queue

		* @since 2.8

        * @return TUint16 amount of elements in queue

        */

        inline TUint16 Count() const { return iCount; };

        /**

        * Inline function to tell the size of queue

		* @since 2.8

        * @return TUint16 size of queue 

        */

        inline TUint16 SizeOf() const { return iSize; };

    protected:

        /**

        * Function to disable interrupts

		* @since 2.8

        * @return TInt KErrNone if succesful

        */

        TInt DisableIrqs();

        /**

        * Function to restore interrupts

		* @since 2.8

        * @param TInt aLevel level where interrupts should be restored

        * @return void 

        */

        void RestoreIrqs( TInt aLevel );

        volatile TUint16 iHead;

        volatile TUint16 iTail;

        volatile TUint16 iCount;

        TUint16          iSize;

        TUint32**        iQueue;

    };

#endif      // DISCQUEUE_H

// End of File