// Copyright (c) 1998-2009 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\sfat32\inc\sl_facache32.h

// FAT32 various cache classes definition

// 

//

/**

 @file

 @internalTechnology

*/

#ifndef SL_FAT_CACHE_32_INL

#define SL_FAT_CACHE_32_INL

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

void CFatBitCache::SetState(CFatBitCache::TState aState) 

    {

    iState = aState;

    }

/**

    Converts FAT index to the corresponding bit array bit number (or FAT cache sector number).

    @param  aFatIndex index in the FAT 

    @return corresponding index in the FAT bit array

*/

TUint32 CFatBitCache::FatIndexToCacheSectorNumber(TUint32 aFatIndex) const

    {

    ASSERT(aFatIndex >= KFatFirstSearchCluster);

    return (aFatIndex >> iFatIdxToSecCoeff);

    }

/**

    Converts FAT32 cache sector number to the FAT32 entry index (in the beginning of this cache sector)

    @param  aCacheSecNum index in the FAT bit array (or FAT cache sector number)

    @return corresponding index in the FAT 

*/

TUint32 CFatBitCache::CacheSectorNumberToFatIndex(TUint32 aCacheSecNum) const

    {

    ASSERT(aCacheSecNum < iBitCache.Size());

    return (aCacheSecNum << iFatIdxToSecCoeff);

    }

/** @return state of the cache*/

CFatBitCache::TState CFatBitCache::State() const 

    {

    return iState;

    }

/** 

    @return ETrue if the cache can be used, i.e. is fully populated

*/

TBool CFatBitCache::UsableState() const

    {

    return State() == EPopulated;

    }

/**

    @return ETrue if the FAT cache sector number "aFatSectorNum" is marked as having at least one free FAT entry.

    N.B. The cache must be in consistent state, i.e. fully populated.

*/

TBool CFatBitCache::FatSectorHasFreeEntry(TUint32 aFatSectorNum) const

    {

    ASSERT(UsableState());

    return iBitCache[aFatSectorNum];

    }

/**

    Mark FAT cache sector number "aFatSectorNum" is as having/not having free FAT entry.

    N.B. The cache must be in consistent state, i.e. fully populated.

    @param  aFatSectorNum FAT32 cache sector number [index in a bit vector] 

    @param  aHasFreeEntry ETrue  if we want to mark this sector as having free FAT entries; 

                          EFalse if we want to mark this sector as NOT having free FAT entries; 

*/

void CFatBitCache::SetFreeEntryInFatSector(TUint32 aFatSectorNum, TBool aHasFreeEntry)

    {

    ASSERT(UsableState());

    iBitCache.SetBitVal(aFatSectorNum, aHasFreeEntry);

    }

#endif //SL_FAT_CACHE_32_INL