linklayerprotocols/pppnif/INC/vjcomp.inl
author Dremov Kirill (Nokia-D-MSW/Tampere) <kirill.dremov@nokia.com>
Tue, 26 Jan 2010 15:23:49 +0200
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// Copyright (c) 2003-2009 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 "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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//
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#if !defined(__VJCOMP_INL_)
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#define __VJCOMP_INL_
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/**
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Tests if the delta value is compressible into the 16 bit VJ delta format.
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The aDelta value actually needs a 33 bit signed integer to hold the entire
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possible range, but the twos complement math works out if it's just
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stored as a 32 bit unsigned integer.
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@param aDelta Delta value to test
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@return ETrue if the value is compressible
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*/
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inline TBool CVJCompressor::IsDeltaCompressible(TUint32 aDelta) const
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	{
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	// This test is a faster equivalent to:
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	//    (aDelta >= 0) && (aDelta <= 0xffff)
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	// if aDelta were signed
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	return !(aDelta & 0xffff0000);
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	}
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inline TUint8* CVJCompressor::GetTCPOpts(ThdrTCP* aTCPHeader) const
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/**
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Returns a pointer to the start of the TCP options (if there are any).
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@param aTCPHeader TCP header
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@return Start of the TCP options
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*/
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	{
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	TUint8* aPtr = (TUint8*)aTCPHeader+KTCPHeaderSize;
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	return aPtr;
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	}
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#endif // __VJCOMP_INL_
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