/*

* Copyright (c) 2010 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:

*

*/

/**

@file

@internalComponent

*/

#include "ncmbuffermanager.h"

#include "OstTraceDefinitions.h"

#ifdef OST_TRACE_COMPILER_IN_USE

#include "ncmbuffermanagerTraces.h"

#endif

// if there are KCongestionCount buffers will notify networking to stop sending

// if there are at least KUnCongestionCount, will notify networking to start sending

const TInt KCongestionCount = 1;

const TInt KUnCongestionCount = 3;

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

//

CNcmBufferManager* CNcmBufferManager::NewL()

    {

    OstTraceFunctionEntry0( CNCMBUFFERMANAGER_NEWL_ENTRY );

    CNcmBufferManager *self = new (ELeave) CNcmBufferManager();

    OstTraceFunctionExit0( CNCMBUFFERMANAGER_NEWL_EXIT );

    return self;

    }

CNcmBufferManager::~CNcmBufferManager()

    {

    OstTraceFunctionEntry1( CNCMBUFFERMANAGER_CNCMBUFFERMANAGER_ENTRY, this );

    iFreeQueue.Reset();

    OstTraceFunctionExit1( CNCMBUFFERMANAGER_CNCMBUFFERMANAGER_EXIT, this );

    }

//

// get a buffer block from manager

//

TInt CNcmBufferManager::GetBuffer(TNcmBuffer& aBuffer)

    {

	OstTraceFunctionEntry1( CNCMBUFFERMANAGER_GETBUFFER_ENTRY, this );

    TInt count = iFreeQueue.Count();

    TInt ret = KErrNone;

    if (count == 0)

        {

        OstTraceFunctionExit1( CNCMBUFFERMANAGER_GETBUFFER_EXIT, this );

        return KErrNoBuffer;

        }

    else if (count == KCongestionCount)

        {

        iIsCongestion = ETrue;

        ret = KErrCongestion;

        }

    aBuffer = iFreeQueue[0];

    iFreeQueue.Remove(0);

    OstTraceFunctionExit1( CNCMBUFFERMANAGER_GETBUFFER_EXIT_DUP1, this );

    return ret;

    }

//

// free a buffer block to manager

//

void CNcmBufferManager::FreeBuffer(const TNcmBuffer& aBuffer)

    {

    OstTraceFunctionEntry1( CNCMBUFFERMANAGER_FREEBUFFER_ENTRY, this );

    iFreeQueue.Append(aBuffer);  

    int count = iFreeQueue.Count();

    iFreeQueue[count-1].iLen = 0;

    if (count == KUnCongestionCount)

        {

        iIsCongestion = EFalse;

        }

    OstTraceFunctionExit1( CNCMBUFFERMANAGER_FREEBUFFER_EXIT, this );

    }

//

// set the whole buffer area to create buffer blocks

//

void CNcmBufferManager::InitBufferArea(TAny* aBuf, TInt aLength)

    {

    OstTrace1( TRACE_NORMAL, CNCMBUFFERMANAGER_INITBUFFERAREA, "CNcmBufferManager::InitBufferArea aLength=%d", aLength );    

    iBuf = (TUint8*)aBuf;

    iLen = aLength;

    }

//

// set the size of a buffer block, create buffer blocks on the buffer area

//

TInt CNcmBufferManager::SetBufferCellSize(TInt aSize)

    {

    OstTraceFunctionEntry1( CNCMBUFFERMANAGER_SETBUFFERCELLSIZE_ENTRY, this );

//    buffer block size must be aligned with KAlignSize to make the each buffer start align with KAlignSize 

    iCellSize = (aSize+iAlignSize-1)&~(iAlignSize-1);

    OstTraceExt2( TRACE_NORMAL, CNCMBUFFERMANAGER_SETBUFFERCELLSIZE, "CNcmBufferManager::SetBufferCellSize aSize=%d, iCellSize=%d", aSize, iCellSize );

//   buffer area got from share chunk LDD may not align, make it align to KAlignSize first

    TUint32 buf = (TUint)iBuf;

    buf = (buf+iAlignSize-1)&~(iAlignSize-1);

    TUint8* alignbuf = (TUint8*)buf;

    TUint32 offset = buf - (TUint)iBuf;

    int count = (iLen-offset)/iCellSize;

    iFreeQueue.Reset();

    if (count < KUnCongestionCount)

        {        

        OstTrace1( TRACE_FATAL, CNCMBUFFERMANAGER_SETBUFFERCELLSIZE1, "the buffer cell size is too big and create too less buffers %d", count );

        OstTraceFunctionExit1( CNCMBUFFERMANAGER_SETBUFFERCELLSIZE_EXIT, this );

        return KErrUnknown;

        }

    TNcmBuffer ncmbuf;

    for (TInt i=0 ; i<count ; i++)

        {

        ncmbuf.iPtr = alignbuf+i*iCellSize;

        ncmbuf.iLen = 0;

        ncmbuf.iMaxLength = iCellSize;

        iFreeQueue.Append(ncmbuf);

        }

    iIsCongestion = EFalse;

    OstTraceFunctionExit1( CNCMBUFFERMANAGER_SETBUFFERCELLSIZE_EXIT_DUP1, this );

    return KErrNone;

    }

CNcmBufferManager::CNcmBufferManager()

    {

    iIsCongestion = EFalse;

    }

//

// if there is not enough buffer blocks, return ETrue and will start flow control in networking

//

TBool CNcmBufferManager::IsCongestion()

    {

    OstTrace1( TRACE_NORMAL, CNCMBUFFERMANAGER_ISCONGESTION, "CNcmBufferManager::FreeBufferCount %d", iFreeQueue.Count() );

    return iIsCongestion;

    }

TInt CNcmBufferManager::RequiredBufferCount()

    {

    return KUnCongestionCount;

    }