/*

* 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 the License "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 "msgqueue.h"           // For DMsgQueue

#include "p2proutertrace.h"     // For C_TRACE..

// Fault identifiers

enum TDMsgQueueFaults

    {

    EDMsgQueueMemAllocFail = 0x00,

    EDMsgQueueMemAllocFail2,

    EDMsgQueueInvalidQueueSize,

    EDMsgQueueNotEmpty,

    EDMsgQueueNotInSync,

    EDMsgQueueNotInSync2,

    EDMsgQueueNotInSync3,

    EDMsgQueueNotInSync4,

    EDMsgQueueNotInSync5,

    };

DMsgQueue::DMsgQueue(

        const TUint16 aSize

        )

    {

    C_TRACE( ( _T( "DMsgQueue::DMsgQueue 0x%x %d>" ), this, aSize ) );

    iQueueMutex = new NFastMutex();

    ASSERT_RESET_ALWAYS( iQueueMutex, ( EDMsgQueueMemAllocFail | EDMsgQueueTraceId << KClassIdentifierShift ) );

    iSize = aSize;

    ASSERT_RESET_ALWAYS( ( iSize > 0 ), ( EDMsgQueueInvalidQueueSize | EDMsgQueueTraceId << KClassIdentifierShift ) );

    iShInputIndex = 0;

    iShOutputIndex = 0;

    iShCount = 0;

    // Reserve memory for the buffer.

    iShRingBuffer = new TDes8*[ aSize ];

    C_TRACE( ( _T( "DMsgQueue::DMsgQueue 0x%x" ), iShRingBuffer ) );

    ASSERT_RESET_ALWAYS( iShRingBuffer, ( EDMsgQueueMemAllocFail2 | EDMsgQueueTraceId << KClassIdentifierShift ) );

    for( TInt i( 0 ); i < iSize; ++i )

        {

        iShRingBuffer[ i ] = NULL;

        }

    C_TRACE( ( _T( "DMsgQueue::DMsgQueue 0x%x<" ), this ) );

    }

DMsgQueue::~DMsgQueue(

        // None

        )

    {

    C_TRACE( ( _T( "DMsgQueue::~DMsgQueue 0x%x %d>" ), this, iShCount ) );

    ASSERT_RESET_ALWAYS( iShCount == 0, ( EDMsgQueueNotEmpty | EDMsgQueueTraceId << KClassIdentifierShift ) );

    // NOTE! This does not deallocate the blocks from the allocated memory just the pointers!

    for( TInt i( 0 ); i < iSize; ++i )

        {

        TDes8* temp = iShRingBuffer[ i ];

        if( temp )

            {

            C_TRACE( ( _T( "DMsgQueue::~DMsgQueue ptr 0x%x" ), temp ) );

            delete temp;

            temp = NULL;

            }

        }

    if( iShRingBuffer )

        {

        C_TRACE( ( _T( "DMsgQueue::~DMsgQueue iShRingBuffer 0x%x iShRingBuffer[0] 0x%x" ), iShRingBuffer, iShRingBuffer[0] ) );

        delete [] iShRingBuffer;

        iShRingBuffer = NULL;

        }

    iSize = 0;

    iShInputIndex = 0;

    iShOutputIndex = 0;

    iShCount = 0;

    C_TRACE( ( _T( "DMsgQueue::~DMsgQueue iQueueMutex" ) ) );

    // Only modified in constructor if allocated failed, already reseted.

    delete iQueueMutex;

    iQueueMutex = NULL;

    C_TRACE( ( _T( "DMsgQueue::~DMsgQueue 0x%x<" ), this ) );

    }

void DMsgQueue::Add(

        const TDesC8& aMessage

        )

    {

    C_TRACE( ( _T( "DMsgQueue::Add 0x%x %d %d %d %d 0x%x>" ), this, iSize, iShCount, iShInputIndex, iShOutputIndex, &aMessage ) );

    NKern::FMWait( iQueueMutex );

    // If queue get's overfilled throw kernel fault.

    ASSERT_RESET_ALWAYS( ( iShCount < iSize ), ( EDMsgQueueNotInSync | EDMsgQueueTraceId << KClassIdentifierShift ) );

    // Place the buffer into the queue.

    iShRingBuffer[ iShInputIndex ] = static_cast<TDes8*>( &const_cast<TDesC8&>( aMessage ) );

    // Adjust input pointer.

    iShInputIndex = ( ( iShInputIndex + 1 ) % iSize );

    // Remember the amount of the requests in the queue.

    iShCount++;

    NKern::FMSignal( iQueueMutex );

    C_TRACE( ( _T( "DMsgQueue::Add 0x%x %d %d %d %d 0x%x<" ), this, iSize, iShCount, iShInputIndex, iShOutputIndex, &aMessage ) );

    }

TUint16 DMsgQueue::Count(

        // None

        )

    {

    C_TRACE( ( _T( "DMsgQueue::Count 0x%x %d>" ), this, iShCount ) );

    TUint16 count( KErrNone );

    NKern::FMWait( iQueueMutex );

    // If count is too big.

    ASSERT_RESET_ALWAYS( ( iShCount <= iSize ), ( EDMsgQueueNotInSync2 | EDMsgQueueTraceId << KClassIdentifierShift ) );

    count = iShCount;

    NKern::FMSignal( iQueueMutex );

    C_TRACE( ( _T( "DMsgQueue::Count 0x%x %d %d<" ), this, iShCount, count ) );

    return count;

    }

TDes8& DMsgQueue::Get(

        // None

        )

    {

    C_TRACE( ( _T( "DMsgQueue::Get 0x%x %d %d %d %d>" ), this, iSize, iShCount, iShInputIndex, iShOutputIndex ) );

    NKern::FMWait( iQueueMutex );

    // If queue is empty.

    ASSERT_RESET_ALWAYS( ( iShCount > 0 ), ( EDMsgQueueNotInSync3 | EDMsgQueueTraceId << KClassIdentifierShift ) );

    // Get the buffer from the queue.

    TDes8* temp = iShRingBuffer[ iShOutputIndex ];

    // Set buffer location to NULL.

    iShRingBuffer[ iShOutputIndex ] = NULL;

    // Adjust output pointer.

    iShOutputIndex = ( ( iShOutputIndex + 1 ) % iSize );

    // Remember the amount of the requests in the queue.

    iShCount--;

    NKern::FMSignal( iQueueMutex );

    ASSERT_RESET_ALWAYS( temp, ( EDMsgQueueNotInSync4 | EDMsgQueueTraceId << KClassIdentifierShift ) );

    C_TRACE( ( _T( "DMsgQueue::Get 0x%x %d %d %d %d 0x%x<" ), this, iSize, iShCount, iShInputIndex, iShOutputIndex, temp ) );

    return *temp;

    }

void DMsgQueue::RollBack(

        const TDesC8& aMsgToRoll

        )

    {

    C_TRACE( ( _T( "DMsgQueue::RollBack 0x%x %d %d %d %d 0x%x>" ), this, iSize, iShCount, iShInputIndex, iShOutputIndex, &aMsgToRoll ) );

    NKern::FMWait( iQueueMutex );

    ASSERT_RESET_ALWAYS( ( iShCount < iSize ), ( EDMsgQueueNotInSync5 | EDMsgQueueTraceId << KClassIdentifierShift ) );

    // If needs to rollback from 0 to iSize -1 index.

    iShOutputIndex = ( iShOutputIndex == 0 ) ? iSize : iShOutputIndex; 

    // Adjust output pointer.

    iShOutputIndex = ( ( iShOutputIndex - 1 ) % iSize );

    // Get the descriptor from queue where the rollback is made.

    iShRingBuffer[ iShOutputIndex ] = static_cast<TDes8*>( &const_cast<TDesC8&>( aMsgToRoll ) );

    // Remember the amount of the requests in the queue.

    iShCount++;    

    NKern::FMSignal( iQueueMutex );

    C_TRACE( ( _T( "DMsgQueue::RollBack 0x%x %d %d %d %d 0x%x<" ), this, iSize, iShCount, iShInputIndex, iShOutputIndex, &aMsgToRoll ) );

    }

// End of file.