// Copyright (c) 1995-2009 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:

// 

/**

    @file

    @internalTechnology

*/

#if !defined(__FILESYSTEM_UTILS_INL__)

#define __FILESYSTEM_UTILS_INL__

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

/** @return 2^aVal */

inline TUint32 Pow2(TUint32 aVal)

    {

    ASSERT(aVal<32);

    return 1 << aVal;

    }

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

/** @return TUint32 value equals 2^aVal */

inline TUint32 Pow2_32(TUint32 aVal)

    {

    ASSERT(aVal < 32);

    return 1 << aVal;

    }

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

/** @return TUint64 value equals 2^aVal */

inline TUint64 Pow2_64(TUint32 aVal)

    {

    ASSERT(aVal < 64);

    return ((TUint64)1) << aVal;

    }

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

/**

    Indicates if a number passed in is a power of two

    @return ETrue if aVal is a power of 2 

*/

inline TBool IsPowerOf2(TUint32 aVal)

    {

    if (aVal==0)

        return EFalse;

    return !(aVal & (aVal-1));

    }

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

/**

    Indicates if a number passed in is a power of two

    @return ETrue if aVal is a power of 2 

*/

inline TBool IsPowerOf2_64(TUint64 aVal)

    {

    if (aVal==0)

        return EFalse;

    return !(aVal & (aVal-1));

    }

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

/**

    rounds down the given value to 2^aGranularityLog2

    @param  aVal                input value to round down

    @param  aGranularityLog2    Log2(granularity)

    @return rounded - down value

*/

inline TUint32 RoundDown(TUint32 aVal, TUint32 aGranularityLog2)

{

    ASSERT(aGranularityLog2 < 32);

    return (aVal >> aGranularityLog2) << aGranularityLog2;

}

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

/**  

    Rounds up aVal to the 2^aGranularityLog2 

    For example: RoundUp(0x08, 2) == 0x08; RoundUp(0x08, 3) == 0x08; RoundUp(0x08, 4) == 0x10; RoundUp(0x19, 4) == 0x20

    @return rounded-up value

*/

inline TUint32 RoundUp(TUint32 aVal, TUint32 aGranularityLog2)

    {

    ASSERT(aGranularityLog2 < 32);

    if( (aVal & ((1<<aGranularityLog2)-1)) == 0)

        return aVal;    

    aVal >>= aGranularityLog2;

    aVal++;

    aVal <<= aGranularityLog2;

    return aVal;

    }

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

/**

    @return Boolean exclusive OR between a1 and a2

    This function should be used on C-style TBool, which is, actually TInt type; Its '0' value means "False" and _any_ non-zero means "True"

    E.g: BoolXor(0x17, 0x4a) == EFalse;

*/

TBool BoolXOR(TBool a1, TBool a2)

    {

    if(!a1 && !a2)        

        return EFalse;

    else if(a1 && a2)

        return EFalse;

    else

        return ETrue;

    }

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

/**

    Calculates the log2 of a number

    This is the explicitly inlined version. Extensive using it may result in a code bloat.

    @param aNum Number to calulate the log two of

    @return The log two of the number passed in

*/

inline TUint32 Log2_inline(TUint32 aVal)

    {

    __ASSERT_COMPILE(sizeof(TUint32) == 4);

    ASSERT(aVal);

    TUint32 bitPos=31;

    if(!(aVal >> 16)) {bitPos-=16; aVal<<=16;}

    if(!(aVal >> 24)) {bitPos-=8;  aVal<<=8 ;}

    if(!(aVal >> 28)) {bitPos-=4;  aVal<<=4 ;}

    if(!(aVal >> 30)) {bitPos-=2;  aVal<<=2 ;}

    if(!(aVal >> 31)) {bitPos-=1;}

    return bitPos;

    }

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

/**

    Calculates number of '1' bits in the aVal

    This is the explicitly inlined version. Extensive using it may result in a code bloat.

    @param aVal some value

    @return number of '1' bits in the aVal

*/

inline TUint32 Count1Bits_inline(TUint32 aVal)

    {

    if(!aVal)

        return 0;

    if(aVal == 0xFFFFFFFF)

        return 32;

    aVal = aVal - ((aVal >> 1) & 0x55555555);

    aVal = (aVal & 0x33333333) + ((aVal >> 2) & 0x33333333);

    aVal = (aVal + (aVal >> 4)) & 0x0f0f0f0f;

    aVal = aVal + (aVal >> 8);

    aVal = aVal + (aVal >> 16);

    return aVal & 0x3f;

    }

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

/** clear all bits */

void T32Bits::Clear()

    {

    iData = 0;

    }

/** @return non-0 if at least one of 32 bits is set to '1' */

TBool T32Bits::HasBitsSet() const 

    {

    return iData;

    } 

/** sets bit number "aIndex" to '1' */

void T32Bits::SetBit(TUint32 aIndex)

    {

    ASSERT(aIndex < 32);

    iData |= (1<<aIndex);

    }

/** 

    Get value of the bit number "aIndex". 

    @return 0 if the bit aIndex is '0' non-zero otherwise

*/

TBool T32Bits::operator[](TUint32 aIndex) const

    {

    ASSERT(aIndex < 32);

    return (iData & (1<<aIndex));

    }

#endif //__FILESYSTEM_UTILS_INL__