/*

* 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: Declaration for CMMCScBkupReadDataTransferRequestBase

*     

*

*/

#ifndef __CMMCSCBKUPTRANSFERREADREQUEST_H__

#define __CMMCSCBKUPTRANSFERREADREQUEST_H__

// User includes

#include "MMCScBkupConfig.h"

#include "MMCScBkupSBEUtils.h"

#include "TMMCScBkupOwnerDataType.h"

#include "CMMCScBkupDataOwnerInfo.h"

#include "CMMCScBkupTransferRequest.h"

#include "CMMCScBkupIndexWithIdentifier.h"

// Classes referenced

class MMMCScBkupDriver;

class CMMCScBkupArchiveFooter;

// Constants

const TInt KMMCScBkupDefaultChunkReadSize = 4096; // 4k read chunks

// CMMCScBkupIndexEntry

/**

*

*

* @since 3.0

*/

NONSHARABLE_CLASS(CMMCScBkupReadDataTransferRequestBase) : public CMMCScBkupTransferRequestBase

    {

    public:

        /**

        * C++ destructor

        */

        ~CMMCScBkupReadDataTransferRequestBase();

    protected:

        /**

        * C++ default constructor

        */

        CMMCScBkupReadDataTransferRequestBase( MMMCScBkupDriver& aDriver, 

                                               TMMCScBkupOwnerDataType aElementType,

                                               TInt aChunkSize = KMMCScBkupDefaultChunkReadSize,

                                               TInt aPriority = CActive::EPriorityIdle );

    public: // API

        /**

        *

        */

        void RequestL( CMMCScBkupDataOwnerInfo& aOwner, TRequestStatus& aObserver, const RArray<TMMCScBkupArchiveDriveAndVector>& aEntries );

    protected: // New Framework API

        /**

        *

        */

        virtual CSBGenericTransferType* PrepareTransferTypeL( const CSBGenericDataType& aGeneric, 

            TDriveNumber aDrive, TInt aVersion ) const = 0;

    private: // From CMMCScBkupTransferRequest

        TBool ProcessChunkOfDataL();

        void PrepareDataTransferL();

    private: // Internal methods

        /**

        *

        */

        void ReadChunkL( TDes8& aSink, TInt aLength );

        /**

        *

        */

        TBool DoProcessChunkOfDataL();

        /**

        *

        */

        TBool PrepareForNextEntry();

        /**

        *

        */

        TDriveNumber CurrentDrive() const;

        /**

        *

        */

        const TMMCScBkupArchiveVector& CurrentReadInfo() const;

        /**

        *

        */

        const TMMCScBkupArchiveDriveAndVector& CurrentEntry() const;

        /**

        *

        */

        inline TInt CurrentOffset() const { return iCurrentOffset; }

    private: // From CActive

        TInt RunError( TInt aError );

    private: // Debugging support

        /**

        *

        */

#ifdef DEBUGGING_DATA_TRANSFER

        void DumpTransferDataL( RFs& aFsSession, const TDesC8& aData ) const;

#endif

    private: // Member data

        // Owned externally

        //

        const RArray<TMMCScBkupArchiveDriveAndVector>* iEntries;

        // Owned by this object

        // Pointer to the SBE's shared chunk. It *must* be a reference

        // because otherwise the SBE loses track of what we actually write

        // to the chunk!

        TPtr8* iTransferChunkPointer;

        //

        const TInt iReadChunkSize;

        //

        TInt iCurrentIndex;

        //

        TBool iFinishedSupplyingData;

        //

        CSBGenericTransferType* iTransferType;

        //

        TInt iCurrentOffset;

        //

        HBufC8* iTemporaryTransferSink;

    };

/**

*

*

* @since 3.0

*/

template <class Type>

class CMMCScBkupReadDataTransferRequest : public CMMCScBkupReadDataTransferRequestBase

    {

    public: // Construction

        /**

        *

        */

        inline static CMMCScBkupReadDataTransferRequest* NewL( MMMCScBkupDriver& aDriver, 

                                                        TMMCScBkupOwnerDataType aElementType,

                                                        Type aTransferEnumType,

                                                        TInt aChunkSize = KMMCScBkupDefaultChunkReadSize,

                                                        TInt aPriority = CActive::EPriorityIdle )

            {

            CMMCScBkupReadDataTransferRequest<Type>* self = new(ELeave) CMMCScBkupReadDataTransferRequest<Type>( aDriver, aElementType, aTransferEnumType, aChunkSize, aPriority );

            return self;

            }

    private: // Internal construction

        /**

        * C++ default constructor

        */

        inline CMMCScBkupReadDataTransferRequest( MMMCScBkupDriver& aDriver, 

                                           TMMCScBkupOwnerDataType aElementType,

                                           Type aTransferEnumType,

                                           TInt aChunkSize = KMMCScBkupDefaultChunkReadSize,

                                           TInt aPriority = CActive::EPriorityIdle )

        :   CMMCScBkupReadDataTransferRequestBase( aDriver, aElementType, aChunkSize, aPriority), 

            iTransferEnumType( aTransferEnumType )

            {

            }

    private: // From CMMCScBkupTransferRequest

        inline CSBGenericTransferType* PrepareTransferTypeL( const CSBGenericDataType& aGeneric, 

            TDriveNumber aDrive, TInt aVersion ) const

            {

            CSBGenericTransferType* transferType = MMCScBkupSBEUtils::TransferTypeLC( aGeneric, aDrive, 

                iTransferEnumType, aVersion );

            CleanupStack::Pop( transferType );

            return transferType;

            }

    private: // Member data

        //

        Type iTransferEnumType;

    };

#endif // __CMMCSCBKUPTRANSFERREADREQUEST_H__

// End of File