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// Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
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// All rights reserved.
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// This component and the accompanying materials are made available
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// under the terms of the License "Eclipse Public License v1.0"
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// which accompanies this distribution, and is available
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// at the URL "http://www.eclipse.org/legal/epl-v10.html".
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//
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// Initial Contributors:
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// Nokia Corporation - initial contribution.
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//
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// Contributors:
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//
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// Description:
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// Utility functions for the Mass Storage file system.
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//
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//
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/**
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@file
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@internalTechnology
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*/
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#include <e32std.h>
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#include <e32std_private.h>
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/**
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Returns ETrue if aNum is a power of two
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*/
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GLDEF_C TBool IsPowerOfTwo(TInt aNum)
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{
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if (aNum==0)
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return(EFalse);
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while(aNum)
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{
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if (aNum & 0x01)
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{
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if (aNum>>1)
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return EFalse;
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break;
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}
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aNum>>=1;
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}
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return ETrue;
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}
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/**
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Returns the position of the highest bit in aNum or -1 if aNum == 0
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*/
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GLDEF_C TInt Log2(TInt aNum)
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{
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TInt res=-1;
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while(aNum)
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{
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res++;
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aNum>>=1;
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}
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return(res);
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}
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