// 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:

// e32\euser\maths\um_frac.cpp

// Writes the fractional part of aTrg to aSrc

// 

//

#include "um_std.h"

#if defined(__USE_VFP_MATH) && !defined(__CPU_HAS_VFP)

#error	__USE_VFP_MATH was defined but not __CPU_HAS_VFP - impossible combination, check variant.mmh 

#endif

#ifndef __USE_VFP_MATH

#ifndef __REALS_MACHINE_CODED__

EXPORT_C TInt Math::Frac(TReal &aTrg,const TReal &aSrc)

/**

Calculates the fractional part of a number.

The fractional part is that after a decimal point.

Truncation is toward zero, so that

Frac(2.4)=0.4, Frac(2)=0, Frac(-1)=0, Frac(-1.4)=0.4.

@param aTrg A reference containing the result.

@param aSrc The number whose fractional part is required. 

@return KErrNone if successful, otherwise another of

        the system-wide error codes.

*/

	{

	TRealX f;

	TInt ret=f.Set(aSrc);

	if (ret!=KErrNone)

		{

		if (ret==KErrArgument)

			SetNaN(aTrg);

		if (ret==KErrOverflow)

			SetZero(aTrg,f.iSign&1);

		return(ret);

		}

	TInt intbits=f.iExp-0x7FFE;

	if (intbits<=0)	 // aSrc is already a fraction

		{

		aTrg=aSrc;

		return(KErrNone);

		}

	if (intbits>KMantissaBits)

		{

		SetZero(aTrg,f.iSign&1);

		return(KErrNone);

		}

	// calculate integer part and subtract

	// this means that the subtraction normalises the result

	TRealX g=f;

	TUint64 mask = ~(UI64LIT(0));

	mask <<= (64 - intbits);

	g.iMantHi &= static_cast<TUint32>(mask >> 32);

	g.iMantLo &= static_cast<TUint32>(mask);

	f-=g;

	f.GetTReal(aTrg);

	return(KErrNone);

	}

#endif //__REALS_MACHINE_CODED__

#else // __USE_VFP_MATH

// definitions come from RVCT math library

extern "C" TReal modf(TReal,TReal*);

EXPORT_C TInt Math::Frac(TReal& aTrg, const TReal& aSrc)

	{

	if (Math::IsNaN(aSrc))

		{

		SetNaN(aTrg);

		return KErrArgument;

		}

	if (Math::IsInfinite(aSrc))

		{

		SetZero(aTrg);

		return KErrOverflow;

		}

	TReal temp;

	aTrg = modf(aSrc,&temp);

	return KErrNone;

	}

#endif