// Copyright (c) 1996-2009 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:

// f32\sfat\sl_drv.cpp

// 

//

#include "sl_std.h"

#include "sl_cache.h"

const TInt KMaxRecoverableRetries=10;

const TInt KMaxCriticalRetries=10;

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

TFatDriveInterface::TFatDriveInterface() 

                   :iMount(NULL)

{

}

/**

    Initialise the interface object.

    @param  aMount the CFatMountCB that owns this object

*/

TBool TFatDriveInterface::Init(CFatMountCB* aMount)

{

    ASSERT(aMount);

    iMount = aMount;

	aMount->LocalDrive()->SetMount(aMount);

    return iProxyDrive.Init(aMount->LocalDrive());

}

/**

    pseudo-destructor. 

*/

void TFatDriveInterface::Close()

{

	 if(iMount)

		iMount->LocalDrive()->SetMount(NULL);

     iMount = NULL;

}

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

/**

    Read data from the media via CProxyDrive interface.

    This is non-critical read: on error Non-critical notifier is involved

    @param  aPos        absolute media position

    @param  aLength     how many bytes to read

    @param  aTrg        data descriptor

    @return KErrNone - success

    @return KErrNotReady - non-critical error

    @return KErrCorrupt - an illegal write is detected

    @return KErrBadPower - failure due to low power

*/

TInt TFatDriveInterface::ReadNonCritical(TInt64 aPos, TInt aLength, TDes8& aTrg) const

{

    TInt nRes = KErrNone;

    TInt cntRetry = KMaxRecoverableRetries;

    //__PRINT2(_L("#=+++ Read_nc1: pos:%LU, len:%u"), aPos, aLength);

    for(;;)

    {

        nRes = iProxyDrive.Read(aPos,aLength,aTrg);

        if (nRes==KErrNone)

            break;

        __PRINT4(_L("TFatDriveInterface::ReadNonCritical() failure! drv:%d Posl=%LU len=%d retval=%d"), iMount->DriveNumber(), aPos, aLength, nRes);

        if(--cntRetry <= 0)

        {

            nRes = KErrCorrupt;

            break;

        }

        nRes = HandleRecoverableError(nRes);

        if (nRes !=ERetry)

            break;

    }

    return nRes;

}

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

/**

    Read data from the media via CProxyDrive interface. 

    This is non-critical read: on error Non-critical notifier is involved

    @param  aPos        absolute media position

    @param  aLength     how many bytes to read

    @param  aTrg        data descriptor

    @param  aMessage

    @param  anOffset

    @return KErrNone - success

    @return KErrNotReady - non-critical error

    @return KErrCorrupt - an illegal write is detected

    @return KErrBadPower - failure due to low power

*/

TInt TFatDriveInterface::ReadNonCritical(TInt64 aPos,TInt aLength,const TAny* aTrg,const RMessagePtr2 &aMessage,TInt anOffset) const

{

    //__PRINT2(_L("#=+++ Read_nc2: pos:%LU, len:%u"), aPos, aLength);

    TInt nRes = KErrNone;

    TInt cntRetry = KMaxRecoverableRetries;

    for(;;)

    {

        nRes = iProxyDrive.Read(aPos, aLength, aTrg, aMessage, anOffset);

        if (nRes==KErrNone)

            break;

        __PRINT4(_L("TFatDriveInterface::ReadNonCritical() Failure! drv:%d aPosl=%d len=%d anOffset=%d"), iMount->DriveNumber(), aPos,aLength, anOffset);

        if(--cntRetry <= 0)

        {

            nRes = KErrCorrupt;

            break;

        }

        nRes = HandleRecoverableError(nRes);

        if (nRes !=ERetry)

            break;

    }

    return nRes;

}

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

/**

    Read data from the media via CProxyDrive interface with a critical notifier.

    This method shall be used to read critical filesystem data, such as directory entries, FAT data.

    @param  aPos        absolute media position

    @param  aLength     how many bytes to read

    @param  aTrg        data descriptor

    @return KErrNone - success

    @return KErrNotReady - non-critical error

    @return KErrCorrupt - an illegal write is detected

    @return KErrAbort - user aborted read

*/

TInt TFatDriveInterface::ReadCritical(TInt64 aPos,TInt aLength,TDes8& aTrg) const

{

    //__PRINT2(_L("#=+++ Read_C: pos:%LU, len:%u"), aPos, aLength);

    TInt nRes = KErrNone;

    for(;;)

    {

        nRes = iProxyDrive.Read(aPos, aLength, aTrg);

		if(nRes == KErrNone)

            break;

		__PRINT4(_L("TFatDriveInterface::ReadCritical() Error! drv:%d Posl=%LU len=%d retval=%d"), iMount->DriveNumber(), aPos, aLength, nRes);

        nRes=HandleCriticalError(nRes);

		if (nRes != ERetry)

            break;

    }

    return nRes;

}

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

/**

    Write data to the media via CProxyDrive interface.

    @param  aPos        absolute media position

    @param  aLength     how many bytes to write

    @param  aSrc        pointer to the data 

    @param  aMessage

    @param  anOffset

    @return KErrNone - success

    @return KErrNotReady - non-critical error

    @return KErrBadPower - write not attempted due to low batteries

    @return KErrCorrupt - an illegal write is detected

    @return KErrAccessDenied - write to protected media

*/

TInt TFatDriveInterface::WriteNonCritical(TInt64 aPos, TInt aLength, const TAny* aSrc, const RMessagePtr2 &aMessage, TInt anOffset)

{

    //__PRINT2(_L("#=+++ Write_NC: pos:%LU, len:%u"), aPos, aLength);

    TInt nRes = KErrNone;

    TInt cntRetry = KMaxRecoverableRetries;

    for(;;)

    {

        iMount->OpenMountForWrite(); //-- make a callback to CFatMountCB to perform some actions on 1st write.

        nRes = iProxyDrive.Write(aPos, aLength, aSrc, aMessage, anOffset);

        if (nRes==KErrNone)

            break;

        __PRINT4(_L("TFatDriveInterface::WriteNonCritical() failure! drv:%d, Pos=%LU len=%d anOffset=%d"), iMount->DriveNumber(), aPos, aLength, anOffset);

        if(--cntRetry <= 0)

        {

            nRes = KErrCorrupt;

            break;

        }

        nRes = HandleRecoverableError(nRes);

        if (nRes !=ERetry)

            break;

    }

    return nRes;

}

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

/**

    Write data to the media via CProxyDrive interface. On error this method can invoke a critical notifier.

    This method is intended to be called for the filesstem critical data, i.e. FAT metadata, such as directory entries,

    FAT table etc.

    @param  aPos  absolute media position

    @param  aSrc  descriptor with the source data

    @return KErrNone - success

    @return KErrNotReady - non-critical error

    @return KErrBadPower - write not attempted due to low batteries

    @return KErrCorrupt - an illegal write is detected

    @return KErrAccessDenied - write to protected media

*/

TInt TFatDriveInterface::WriteCritical(TInt64 aPos, const TDesC8& aSrc)

{

    //__PRINT2(_L("#=+++ Write_C: pos:%LU, len:%u"), aPos, aSrc.Length());

    TInt nRes = KErrNone;

#ifdef _DEBUG

    TBool simulatedWriteFailure = EFalse; //-- if true it means that the write failure has been simulated

    //-- debug interface to simulate write failure

	if(iMount->IsWriteFail())

    {

		if(iMount->WriteFailCount() != 0)

        {

            iMount->DecWriteFailCount();

        }

        else

		{//-- simulate write failure

			if(iMount->WriteFailError()==-99)

				UserSvr::ResetMachine(EStartupWarmReset);

			else

			{

			    //-- invalidate caches, because actual write to the drive isn't going to happen

                if(iMount->RawDisk().DirCacheInterface())

                    iMount->RawDisk().DirCacheInterface()->InvalidateCache();

                iMount->SetWriteFail(EFalse);

                TRAP_IGNORE(iMount->RawDisk().InvalidateUidCache()); //-- invalidate whole UID data cache

                TRAP_IGNORE(iMount->FAT().InvalidateCacheL());       //-- invalidate whole FAT cache

                iMount->InvalidateLeafDirCache();

                nRes = iMount->WriteFailError(); 

                simulatedWriteFailure = ETrue; //-- won't perform actual write later

                __PRINT4(_L("TFatDriveInterface::WriteCritical() Simulating write failure. drv:%d, aPos=%LU len=%d Code=%d"), iMount->DriveNumber(), aPos,aSrc.Length(),nRes);

			}

		}

    }//if(iMount->IsWriteFail())

    if(!simulatedWriteFailure)

#endif // _DEBUG

    {

        //-- try to write data until success or user gives up

	    for(;;)

	    {

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

            {

                iMount->OpenMountForWrite();  //-- make a callback to CFatMountCB to perform some actions on 1st write.

                nRes=iProxyDrive.Write(aPos,aSrc);

			    if (nRes==KErrNone)

                    return nRes;

		    }

            //-- write error occured

            __PRINT4(_L("TFatDriveInterface::WriteCritical() failure! drv:%d, aPos=%LU len=%d retval=%d"), iMount->DriveNumber(), aPos,aSrc.Length(),nRes);

            nRes=HandleCriticalError(nRes);

            if (nRes!=ERetry)

                break;

	    }//for(;;)

    }// if(!simulatedWriteFailure)

    return nRes;

}

/**

    Get Last Error Info from the proxy drive

    @param  aErrorInfo data descriptor for the error info.

    @return KErrNone - success, interrogate aErrorInfo for further info

    @return KErrNotSupported - media driver does not support

*/

TInt TFatDriveInterface::GetLastErrorInfo(TDes8& aErrorInfo) const

{

    return iProxyDrive.GetLastErrorInfo(aErrorInfo);

}

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

/**

    Handle critical error

    @param aResult result from the media driver (error code)

    @return ERetry - Attempt operation again

    @return KErrAbort - User aborted notifier

    @return KErrAccessDenied - media is read only

    @return KErrCorrupt - cf-card is corrupt

*/

TInt TFatDriveInterface::HandleCriticalError(TInt aResult) const

	{

    __PRINT2(_L("TFatDriveInterface::HandleCriticalError drv:%d, code:%d"), iMount->DriveNumber(),aResult);

	TLocaleMessage line1;

	TLocaleMessage line2;

	TInt r=KErrAbort;

	if (aResult==KErrLocked)

	{

		r=KErrLocked;

		goto End;

	}

	if (aResult==KErrAccessDenied)

		{

		r=KErrAccessDenied;

		goto End;

		}

	if (aResult==KErrArgument || aResult==KErrBadDescriptor)

		{

		r=KErrCorrupt;

		goto End;

		}

	if (iMount->Drive().IsChanged())

		{//-- check if the media we accessing is the same as it used to be

          if(iMount->CheckVolumeTheSame())

        	{//-- the media is the same

			if(!IsDriveWriteProtected())

				{

				iMount->Drive().SetChanged(EFalse);

				r=ERetry;

				goto End;

				}

			}

		}

	if (aResult==KErrAbort && !iMount->Drive().IsChanged())

		{

		r=ERetry;

		goto End;

		}

	if (aResult==KErrBadPower)

		{

		line1=EFileServer_LowPowerLine1;

		line2=EFileServer_LowPowerLine2;

		}

	else if (iMount->Drive().IsChanged())

		{

		line1=EFileServer_PutTheCardBackLine1;

		line2=EFileServer_PutTheCardBackLine2;

		}

	else

		{

		line1=EFileServer_DiskErrorLine1;

		line2=EFileServer_DiskErrorLine2;

		}

	if (NotifyUser())

		{

		FOREVER

			{

			TInt buttonVal;

			TInt ret=iMount->Notifier()->Notify(TLocaleMessageText(line1),

												TLocaleMessageText(line2),

												TLocaleMessageText(EFileServer_Button1),

												TLocaleMessageText(EFileServer_Button2),

												buttonVal);

			if (ret!=KErrNone)

				break; 

			if (buttonVal!=1)

				break; // Abort

			if (iMount->Drive().IsChanged())

				{

//

// Without this code, retry will indiscriminately write over whatever disk happens to be present.

// However if the write error is to the bootsector remounting will always fail because the boot

// sector will have changed and hence the disk is useless.

// 

                if(!iMount->CheckVolumeTheSame())

                    continue; //-- the media isn't the same as originally mounted; continue asking

                if(IsDriveWriteProtected())

                    continue; //-- still can not write to the drive

				iMount->Drive().SetChanged(EFalse);

				}

			r=ERetry; // Retry

			break;

			}

		}

End:

	return(r);

	}

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

/**

    Handle recoverable error

    @param aResult result from the media driver (error code)

    @return ERetry - retry write

    @return KErrCorrupt - media is corrupt

    @return KErrBadPower - low power failure

    @return KErrNotReady - non-critical error

*/

TInt TFatDriveInterface::HandleRecoverableError(TInt aResult) const

	{

	__PRINT2(_L("TFatDriveInterface::HandleRecoverableError drv:%d, code:%d"), iMount->DriveNumber(),aResult);

	if (aResult==KErrAccessDenied)

		return(KErrAccessDenied);

	if (aResult == KErrLocked)

		return KErrLocked;

	if (aResult==KErrArgument || aResult==KErrBadDescriptor)

		return(KErrCorrupt);

	if (aResult==KErrBadPower)

		return(KErrBadPower);

	if (aResult==KErrDied)	// client thread died

		return(KErrDied);

	if (iMount->Drive().IsChanged())

		{

        if(! iMount->CheckVolumeTheSame())

            {//-- the media is different now.

            return KErrNotReady;

			}

		else if(!IsRecoverableRemount())

			{

			return KErrAccessDenied;

			}

		}

	return(ERetry);

	}	

/** @return true if the mount can be remounted for a recoverable error */

TBool TFatDriveInterface::IsRecoverableRemount() const

	{

	if(IsDriveWriteProtected()&&(iMount->Drive().IsWriteableResource()||iMount->Drive().IsCurrentWriteFunction()))

		return(EFalse);

	return(ETrue);

	}

/** return true if the media is write protected */

TBool TFatDriveInterface::IsDriveWriteProtected() const

	{

	TLocalDriveCapsV2Buf localDriveCaps;

    TInt r=iProxyDrive.Caps(localDriveCaps);

	if(r!=KErrNone)

		return(EFalse);

	return((localDriveCaps().iMediaAtt&KMediaAttWriteProtected)!=0);

	}

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

TFatDriveInterface::XProxyDriveWrapper::XProxyDriveWrapper() 

                   :iLocalDrive(0) 

{

    TInt nRes = iLock.CreateLocal();

    ASSERT(nRes == KErrNone);

    (void)nRes; 

}

TFatDriveInterface::XProxyDriveWrapper::~XProxyDriveWrapper() 

{

    iLock.Close();

}

/** 

    Initialise interface wrapper.

    @param  aProxyDrive pointer to the raw drive access interface