sl@0: /*
sl@0: * Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: * All rights reserved.
sl@0: * This component and the accompanying materials are made available
sl@0: * under the terms of the License "Eclipse Public License v1.0"
sl@0: * which accompanies this distribution, and is available
sl@0: * at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: *
sl@0: * Initial Contributors:
sl@0: * Nokia Corporation - initial contribution.
sl@0: *
sl@0: * Contributors:
sl@0: *
sl@0: * Description:
sl@0: *
sl@0: */
sl@0: //
sl@0: // tmsmemmap.cpp
sl@0: //
sl@0: // Maps a position to mass storage address space
sl@0: //
sl@0: 
sl@0: /** @file
sl@0: @internalTechnology
sl@0: */
sl@0: 
sl@0: #include <e32def.h>
sl@0: #include <e32err.h>
sl@0: 
sl@0: #include "tmsmemmap.h"
sl@0: #include "debug.h"
sl@0: 
sl@0: 
sl@0: TMsDataMemMap::TMsDataMemMap()
sl@0: 	{
sl@0: 	__MSFNSLOG
sl@0:     Reset();
sl@0: 	}
sl@0: 
sl@0: 
sl@0: /**
sl@0:     Checks that the block is within the limits of the media memory address space
sl@0:     and truncates the length if block extends beyond media size.
sl@0: 
sl@0:    @param aPos [IN] Position of start address [OUT] Adjusted position to real
sl@0:    address on media.
sl@0:    @param aLength [IN] Number of bytes [OUT] Number of bytes truncated in case
sl@0:    of block overflow.
sl@0: 
sl@0:    @return TInt KErrNone if block fits. KErrArgument if start position is
sl@0:    greater than the media size. KErrEof if block extends beyond media size.
sl@0:  */
sl@0: TInt TMsDataMemMap::TranslateDataPos(TInt64& aPos, TInt& aLength) const
sl@0:     {
sl@0: 	__MSFNSLOG
sl@0:     // Map to the actual position on the media
sl@0:     aPos += iDataOffset;
sl@0: 
sl@0:     if (aPos > iSize)
sl@0:         {
sl@0:         return KErrArgument;
sl@0:         }
sl@0: 
sl@0:     TInt64 endPos = aPos + aLength;
sl@0:     if (endPos > iSize)
sl@0:         {
sl@0:         aLength = iSize - aPos;
sl@0:         return KErrEof;
sl@0:         }
sl@0:     return KErrNone;
sl@0:     }
sl@0: 
sl@0: /**
sl@0:    Checks that the block is within the limits of the media memory address space
sl@0: 
sl@0:    @param aPos [IN] Position of start address [OUT] Adjusted position to real
sl@0:    address on media.
sl@0:    @param aLength Number of bytes.
sl@0: 
sl@0:    @return TInt KErrNone if block fits. KErrArgument if start position is
sl@0:    greater than the media size. KErrEof if block extends beyond media size.
sl@0:  */
sl@0: TInt TMsDataMemMap::CheckBlockInRange(TInt64& aPos, TInt aLength) const
sl@0:     {
sl@0: 	__MSFNSLOG
sl@0:     // Map to the actual position on the media
sl@0:     aPos += iDataOffset;
sl@0: 
sl@0:     if (aPos > iSize)
sl@0:         {
sl@0:         return KErrArgument;
sl@0:         }
sl@0: 
sl@0:     TInt64 endPos = aPos + aLength;
sl@0:     if (endPos > iSize)
sl@0:         {
sl@0:         __PXYPRINT2(_L("EOF found 0x%lx x%x"), aPos, aLength);
sl@0:         return KErrEof;
sl@0:         }
sl@0: 
sl@0:     return KErrNone;
sl@0:     }