/*

* Copyright (c) 2009 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:

*

*/

// INCLUDE FILES

#include "menubuf.h"

#include "menumsg.h"

#include "mcsmenu.h"

// ================= MEMBER FUNCTIONS =======================

// ---------------------------------------------------------

// RMenuBuf::Open

// ---------------------------------------------------------

//

TInt RMenuBuf::Open( RMenu& aMenu )

    {

	SetBuf( ERead | EWrite, iBuf.iData, iBuf.iData ); // Empty.

    return CreateSubSession( aMenu, EMenuStreamOpen, TIpcArgs() );

    }

// ---------------------------------------------------------

// RMenuBuf::Open

// ---------------------------------------------------------

//

TInt RMenuBuf::Open( RMenu& aMenu, TInt aFunction, TIpcArgs& aArgs )

    {

    iBuf.iLen = 0;

	SetBuf( ERead | EWrite, iBuf.iData, iBuf.iData ); // Initially empty.

    TPckg<TMenuBuf> buf( iBuf );

    aArgs.Set( 2, &buf );

    TInt err = CreateSubSession( aMenu, aFunction, aArgs );

    if ( !err && iBuf.iLen > 0 )

        {

        // If aFunction provided data, it is already here.

        SetEnd( ERead, iBuf.iData + iBuf.iLen );

        }

    return err;

    }

// ---------------------------------------------------------

// RMenuBuf::Close()

// ---------------------------------------------------------

//

void RMenuBuf::Close()

    {

    // Mind the order: TStreamBuf::Close calls SynchL -> needs an open buf.

    TStreamBuf::Close();

    CloseSubSession( EMenuStreamClose );

    }

// ---------------------------------------------------------

// RMenuBuf::UnderflowL()

// ---------------------------------------------------------

//

TInt RMenuBuf::UnderflowL( TInt /*aMaxLength*/ )

    {

    __ASSERT_DEBUG( Avail( ERead ) == 0, User::Invariant() );

    TInt len;

    IpcReadL( len );

    return len;

    }

// ---------------------------------------------------------

// RMenuBuf::OverflowL()

// ---------------------------------------------------------

//

void RMenuBuf::OverflowL()

    {

    __ASSERT_DEBUG( Avail( EWrite ) == 0, User::Invariant() );

    IpcWriteL();

    }

// ---------------------------------------------------------

// RMenuBuf::DoSynchL()

// ---------------------------------------------------------

//

void RMenuBuf::DoSynchL()

    {

    if ( Lag( ERead ) )

        {

        // Read lag unexpected, we do not support seeking.

        User::Leave( KErrNotSupported );

        }

    IpcWriteL();    // Flush write lag.

	SetBuf( ERead | EWrite, iBuf.iData, iBuf.iData );

    }

// ---------------------------------------------------------

// RMenuBuf::IpcReadL()

// ---------------------------------------------------------

//

void RMenuBuf::IpcReadL( TInt& aLength )

    {

	TPtr8 ptr( iBuf.iData, KMenuStreamBufSize );

    User::LeaveIfError( SendReceive( EMenuStreamRead, TIpcArgs( &ptr ) ) );

    SetBuf( EWrite, iBuf.iData, iBuf.iData );

    SetBuf( ERead, iBuf.iData, iBuf.iData + ptr.Length() );

    aLength = ptr.Length();

    }

// ---------------------------------------------------------

// RMenuBuf::IpcWriteL()

// ---------------------------------------------------------

//

void RMenuBuf::IpcWriteL()

    {

    if ( Lag( EWrite ) )

        {

        TPtrC8 ptr( iBuf.iData, Lag( EWrite ) );

        User::LeaveIfError

            ( SendReceive( EMenuStreamWrite, TIpcArgs( &ptr ) ) );

        }

    SetBuf( ERead, iBuf.iData, iBuf.iData );

    SetBuf( EWrite, iBuf.iData, iBuf.iData + KMenuStreamBufSize );

    }

//  End of File