/*

* Copyright (c) 2006-2007 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:  Network buffer

*

*/

#ifndef IRNETWORKBUFFER_H

#define IRNETWORKBUFFER_H

#include <e32base.h>

//========================================class declaration CIRNetworkBuffer============================================

/**

 * This class is wrapper class which can hold an address of a memory chunk

 * and size (granularity) of memory chunk.

 * This is implemented so as to use with queue like TSglQue

 * iLink is public member and is of a member of type TSglQueLink

 * The memory address is of TUint8* type and address is of type TInt

 * you can assign the address and granularity only when you create an instance

 * and retrive address and size using Des() and GetSize() respectively

 * typical usage is as follows

 * Note: This class DOESN'T take any responsibility of removing memory chunk

 * associated to it when you delete the chunk, since it is not creating the memory

 * chunk it doesn't do deallocation it has to taken care from where you create

 * the memory chunk

 *

 * Since it may require changes we are not using irbuffercontainer.cpp present in IRMediaEngine

 * however the logic is borrowed from IRMediaEngine

 * @code

 *

 * TSglQue<CIRNetworkBuffer> Myque;

 * TInt f_off = _FOFF(CIRNetworkBuffer,iLink);

 * Myque.SetOffset(f_off);

 * TUint8* buffer;

 * TInt sizeofbuffer;

 * CIRNetworkBuffer* bufferholder;

 * bufferholder = CIRNetworkBuffer::NewL(buffer,sizeofbuffer);

 * Myque.AddLast(*bufferholder);

 * TUint8* ptr = bufferholder->Des();

 * TInt size = bufferholder->GetSize();

 * bufferholder = Myque.First();

 * Myque.Remove(*bufferholder);

 * delete bufferholder; //deleting bufferholder doesn't deletes memory allocated

 *			            //to buffer is not getting deleted we have delete it explicitly

 * 

 * delete buffer;

 *

 * @endcode

 *   

 */

NONSHARABLE_CLASS( CIRNetworkBuffer ) : public CBase

	{

											//member functions

public :

	/**

	 * Two Phase NewL

	 * returns an instance CIRNetworkBuffer

	 * Owned by CIRNetworkBuffer

	 * @param aAddress Address of data chunk

	 * @param aSize Size of data chunk

	 * @return instance CIRNetworkBuffer

	 */	

	static CIRNetworkBuffer* NewL( TUint8* aAddress,TInt aSize );

	/**

	 * Two Phase NewLC

	 * Creates an instance CIRNetworkBuffer

	 * Owned by CIRNetworkBuffer

	 * @param aAddress Address of data chunk

	 * @param aSize Size of data chunk

	 * @return instance CIRNetworkBuffer

	 */

	static CIRNetworkBuffer* NewLC( TUint8* aAddress,TInt aSize );

	/**

	 * destructor function

	 * Owned by CIRNetworkBuffer

	 */ 

	~CIRNetworkBuffer();

 	/**	

	 *  Des returns the Address of the chunk;

	 *  Owned by CIRNetworkBuffer Class

	 *  @return address

	 */	

	 TUint8* Des() const;

	/**	

	 *  Size returns the size of the chunk;

	 *  Owned by CIRNetworkBuffer Class

	 *  @return size of chunk

	 */

	 TInt Size() const;	

private:

	/**

	 * Function : CIRNetworkBuffer

	 * default constructor

	 */	

	CIRNetworkBuffer();

	/**

	 * Two Phase ConstructL

	 * Owned by CIRNetworkBuffer

	 * @param aAddress Address of data chunk

	 * @param aSize Size of data chunk

	 */

 	void ConstructL( TUint8* aAddress,TInt aSize );

public:

	/**

	 * Queue Link owned by CIRNetworkBuffer

	 */

	TSglQueLink iLink; 

private:

	/**

	 * Queued buffer pointer owned by CIRNetworkBuffer

	 */

	 TUint8* iDataAddress;

	/**

	 * Size of the chunk

	 */

	 TInt iSize;		

	};

#include "irnetworkbuffer.inl"

#endif //IRNETWORKBUFFER_H