// Copyright (c) 2007-2009 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:

// Implementation of this File System extension

// 

//

/**

 @file

*/

#include "win_drive_ext.h"

//#############################################################################

//# Proxy drive implementation

CWinDrvProxyDrive* CWinDrvProxyDrive::NewL(CProxyDrive* aProxyDrive, CMountCB* aMount)

{

    CWinDrvProxyDrive* pSelf = new(ELeave) CWinDrvProxyDrive(aProxyDrive, aMount);

    return pSelf;

}

CWinDrvProxyDrive::CWinDrvProxyDrive(CProxyDrive* aProxyDrive, CMountCB* aMount)

                  :CBaseExtProxyDrive(aProxyDrive, aMount)  

{

    ASSERT(aProxyDrive && aMount);

    iMount = aMount;

    iProxyDrive = aProxyDrive;

}

CWinDrvProxyDrive::~CWinDrvProxyDrive()

{

    Dismounted();

}

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

/** 

    Initialise the proxy drive (this extension)

    @return standard epoc error code.

*/

TInt CWinDrvProxyDrive::Initialise()

{

    __PRINT(_L("#-- CWinDrvProxyDriveFactory::Initialise()"));

    TInt nRes;

    ASSERT(!ipMedia);

    //-- create a scratch buffer

    nRes = iScratchBuf.CreateMax(65536);

    if(nRes != KErrNone)

        return nRes;

    //-- create media driver object, at present only generic block media supported

    if(!ipMedia)

    {

        const TInt nEpocDrvNum = iMount->DriveNumber();

        ipMedia = new CGenericBlockMedia(nEpocDrvNum);

        if(!ipMedia)

            return KErrNoMemory;

    }

    //-- connect to the media device

    nRes = ipMedia->Connect();

    return  nRes;

}

/**

    Dismount this extension.

    @return standard epoc error code.

*/

TInt CWinDrvProxyDrive::Dismounted()

{

    __PRINT(_L("#-- CWinDrvProxyDriveFactory::Dismounted()"));

    //-- disconnect from the media driver and delete it

    if(ipMedia)

    {

        ipMedia->Disconnect();

        delete ipMedia;

        ipMedia = NULL;

    }

    iScratchBuf.Close();

    return KErrNone;

}

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

TInt CWinDrvProxyDrive::GetInterface(TInt aInterfaceId,TAny*& aInterface,TAny* aInput)

{

	switch(aInterfaceId)

		{

		case ELocalBufferSupport:

			return KErrNone;

		default:

			return CBaseExtProxyDrive::GetInterface(aInterfaceId,aInterface,aInput);

		}

}

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

/**

    Read data from the media.

    @param  aPos    media position to start write with.

    @param  aLength number of bytes to read

    @param  destination data descriptor

    @return standard epoc error code.

*/

TInt CWinDrvProxyDrive::Read(TInt64 aPos, TInt aLength, TDes8& aTrg)

{

    //__PRINT3(_L("#-- CWinDrvProxyDrive::Read()#0 pos:%LU, desLen:%d, desMaxLen:%d"),aPos, aTrg.Length(), aTrg.MaxLength());

    if(aTrg.MaxLength() == 0)

        return KErrNone; //-- nothing to do

    aTrg.SetLength(0);

    TInt nRes = ipMedia->Read(aPos, aLength, aTrg);

    return nRes;

}

//-- try to find a message slot containing the required address

#define GetIndex(msg, aAddress, aIndex)			\

	aIndex = msg.Ptr0() == aAddress ? 0 :				\

				msg.Ptr1() == aAddress ? 1 :			\

					msg.Ptr1() == aAddress ? 2 :		\

						msg.Ptr1() == aAddress ? 3 : -1;

/**

    Read data from the media.

    @param  aPos            media position to start write with.

    @param  aLength         number of bytes to be written

    @param  aTrg            pointer to the destination data descriptor

    @param  aThreadHandle   can specify remote thread where the data will be copied to.

    @param  aOffset         an offset within the data descriptor to the real data to be written (see aTrg).

    @return standard epoc error code.

*/

TInt CWinDrvProxyDrive::Read(TInt64 aPos, TInt aLength, const TAny* aTrg, TInt aThreadHandle, TInt aOffset)

{

    //__PRINT4(_L("#-- CWinDrvProxyDrive::Read()#1 pos:%LU, offset:%d, desLen:%d, desMaxLen:%d"),aPos, aOffset, desData.Length(), desData.MaxLength());

    ASSERT(aTrg);

    //-- N.B. aTrg is a pointer to the data descriptor TDes8 !

    TDes8& orgDes = *((TDes8*)aTrg);

    if(aLength == 0)

        return KErrNone; //-- nothing to do

    if(aOffset < 0 || aOffset+aLength > orgDes.MaxLength())

        return KErrArgument; 

    //-- check if we have local or remote message from a different process

    TBool localMessage = (aThreadHandle == KLocalMessageHandle);

	if(!localMessage)

	{

		RMessage2 msg(*(RMessagePtr2 *) &aThreadHandle);

		localMessage = (msg.Handle() == KLocalMessageHandle);

	}

    if(localMessage)

    {//-- we can just copy data to the descriptor; it is the same process

        TPtr8  desData((TUint8*)(orgDes.Ptr()+aOffset), orgDes.Length()-aOffset);

        return ipMedia->Read(aPos, aLength, desData);

    }

    else

    {//-- we have to read data to the local buffer first and then write to another process 

        TInt  msgSlotIdx = 0;

        RMessage2 msg(*(RMessagePtr2 *) &aThreadHandle);

		GetIndex(msg, aTrg, msgSlotIdx); //-- find out message slot index containing the desctiptor data

		if (msgSlotIdx < 0)

			return KErrArgument;

        TInt  rem = aLength;

        TInt  localOffset = 0;

        while(rem)

        {

            const TInt bytesToRead = Min(rem, iScratchBuf.Size());

            TPtr8 ptrBuf((TUint8*)iScratchBuf.Ptr(), bytesToRead);

            //-- read chunk of data from the media to the local buffer

            TInt nRes = ipMedia->Read(aPos + localOffset, bytesToRead, ptrBuf);

            if(nRes != KErrNone)

                return nRes; //-- media read error

            //-- write data from the local buffer to another process

            nRes = msg.Write(msgSlotIdx, ptrBuf, aOffset+localOffset);

            if(nRes != KErrNone)

                return nRes; 

            rem -= bytesToRead;

            localOffset += bytesToRead;

        }

        return KErrNone;

    }

}

/** the same as above */

TInt CWinDrvProxyDrive::Read(TInt64 aPos,TInt aLength, const TAny* aTrg,TInt aThreadHandle, TInt aOffset,TInt /*aFlags*/)

{

    //__PRINT4(_L("#-- CWinDrvProxyDrive::Read()#2 pos:%LU, offset:%d, desLen:%d, desMaxLen:%d"),aPos, aOffset, desData.Length(), desData.MaxLength());

    return Read(aPos, aLength, aTrg, aThreadHandle, aOffset);

}

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

/**

    Write data to the media.

    @param  aPos    media position to start write with.

    @param  aSrc    data descriptor

    @return standard epoc error code.

*/

TInt CWinDrvProxyDrive::Write(TInt64 aPos, const TDesC8& aSrc)

{

    //__PRINT2(_L("#-- CWinDrvProxyDrive::Write()#0 pos:%LU, desLen:%d"),aPos, aSrc.Length());

    if(aSrc.Length() == 0 )

        return KErrNone; //-- nothing to do

    TInt nRes = ipMedia->Write(aPos, aSrc.Size(), aSrc);

    return nRes;

}

/**

    Write data to the media.

    @param  aPos            media position to start write with.

    @param  aLength         number of bytes to be written

    @param  aSrc            pointer to the data descriptor

    @param  aThreadHandle   can specify remote thread where the data will be got from.

    @param  aOffset         an offset within the data descriptor to the real data to be written (see aSrc).

    @return standard epoc error code.

*/

TInt CWinDrvProxyDrive::Write(TInt64 aPos, TInt aLength, const TAny* aSrc, TInt aThreadHandle, TInt aOffset)

{

    //__PRINT3(_L("#-- CWinDrvProxyDrive::Write()#1 pos:%LU, offset:%d, desLen:%d"),aPos, aOffset, orgDes.Length());

    ASSERT(aSrc);

    TDesC8& orgDes = *((TDesC8*)aSrc);

    if(orgDes.Length() == 0 || aLength == 0)

        return KErrNone; //-- nothing to do

    if(aOffset < 0 || aOffset+aLength > orgDes.Length())

        return KErrArgument; 

    //-- check if we have local or remote message from a different process

    TBool localMessage = (aThreadHandle == KLocalMessageHandle);

	if(!localMessage)

	{

		RMessage2 msg(*(RMessagePtr2 *) &aThreadHandle);

		localMessage = (msg.Handle() == KLocalMessageHandle);

	}

    if(localMessage)

    {//-- we can just copy data from the descriptor; it is the same process

    TPtrC8  dataDes(orgDes.Ptr()+aOffset, orgDes.Length()-aOffset);

    return ipMedia->Write(aPos, aLength, dataDes);

}

    else

    {//-- we have to copy data to the local buffer first and then write to the media.

        TInt  msgSlotIdx = 0;

        RMessage2 msg(*(RMessagePtr2 *) &aThreadHandle);

		GetIndex(msg, aSrc, msgSlotIdx);

		if (msgSlotIdx < 0)

			return KErrArgument;

        TInt  rem = aLength;

        TInt  localOffset = 0;

        while(rem)

        {

            const TInt bytesToWrite = Min(rem, iScratchBuf.Size());

            TInt nRes = msg.Read(msgSlotIdx, iScratchBuf, aOffset+localOffset);

            if(nRes != KErrNone)

                return nRes; 

            nRes = ipMedia->Write(aPos+localOffset, bytesToWrite, iScratchBuf);

            if(nRes != KErrNone)

                return nRes; 

            rem -= bytesToWrite;

            localOffset += bytesToWrite;

        }

        return KErrNone;

    }

}

/** the same as above */

TInt CWinDrvProxyDrive::Write(TInt64 aPos,TInt aLength,const TAny* aSrc,TInt aThreadHandle, TInt aOffset,TInt /*aFlags*/)

{

    //__PRINT3(_L("#-- CWinDrvProxyDrive::Write()#2 pos:%LU, offset:%d, desLen:%d"),aPos, aOffset, orgDes.Length());

    return Write(aPos, aLength, aSrc, aThreadHandle, aOffset);

}

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

/** 

    get drive capabilities 

    @param anInfo packed descriptor of TLocalDriveCaps

    @return standard Epoc error code

*/

TInt CWinDrvProxyDrive::Caps(TDes8& anInfo)

{

    TInt nRes;

    //-- get capabilities of the EPOC drive we are overriding

    nRes = CBaseExtProxyDrive::Caps(anInfo);

    if(nRes != KErrNone)

        return nRes;

    TLocalDriveCaps& orgCaps = ((TLocalDriveCapsBuf&)anInfo)();

    //-- override capabilities with the data from our device.

    ipMedia->GetEpocCaps(orgCaps);

    return KErrNone;

}

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

/** 

    Format whole media.

    This method can be called many times, each call represents the formatting step.

    @param  anInfo specifies the formatting parameters.    

    @return KErrNone if the formatting step has  gone OK.

            KErrEof  if the formatting has finished

            standard epoc error code otherwise.

*/

TInt CWinDrvProxyDrive::Format(TFormatInfo& anInfo)

{

    return ipMedia->Format(anInfo);

}

/** 

    format part of the media 

    @param  aPos    starting media position

    @param  aLength length of the media space to be formatted.

    @return standard epoc error code

*/

TInt CWinDrvProxyDrive::Format(TInt64 aPos, TInt aLength)

{

    return ipMedia->Format(aPos, aLength);

}

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

//#############################################################################

//# Extension factory implementation

CWinDrvProxyDriveFactory::CWinDrvProxyDriveFactory()

{

}

TInt CWinDrvProxyDriveFactory::Install()

{

    _LIT(KExtensionName,"Win_Drive"); //-- this extensoin name.

    __PRINT(_L("#-- CWinDrvProxyDriveFactory::Install()"));

    return(SetName(&KExtensionName));

}

CProxyDrive* CWinDrvProxyDriveFactory::NewProxyDriveL(CProxyDrive* aProxy, CMountCB* aMount)

{

    __PRINT(_L("#-- CWinDrvProxyDriveFactory::NewProxyDriveL()"));

    return (CWinDrvProxyDrive::NewL(aProxy, aMount));

}

/** DLL entrypoint */

extern "C" 

{

    EXPORT_C CProxyDriveFactory* CreateFileSystem()

    {

        __PRINT(_L("#-- Win_Drive extension CreateFileSystem()"));

        return new CWinDrvProxyDriveFactory();

    }

}