williamr@2: // Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: // All rights reserved.
williamr@2: // This component and the accompanying materials are made available
williamr@2: // under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
williamr@2: // which accompanies this distribution, and is available
williamr@2: // at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
williamr@2: //
williamr@2: // Initial Contributors:
williamr@2: // Nokia Corporation - initial contribution.
williamr@2: //
williamr@2: // Contributors:
williamr@2: //
williamr@2: // Description:
williamr@2: // tcpseq.h - TCP sequence numbers
williamr@2: // This module defines a TCP sequence number with mod32 arithmetic.
williamr@2: //
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: /**
williamr@2:  @file tcpseq.h
williamr@2:  @publishedAll
williamr@2:  @released
williamr@2: */
williamr@2: 
williamr@2: #ifndef __TCPSEQ_H__
williamr@2: #define __TCPSEQ_H__
williamr@2: 
williamr@2: #include <e32std.h>
williamr@2: 
williamr@2: 
williamr@2: /**  TCP sequence number with mod-32 arithmetic.
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: class TTcpSeqNum
williamr@2: 	{
williamr@2: public:
williamr@2:   	inline TTcpSeqNum()					  			{ iSeq = 0; }
williamr@2:   	inline TTcpSeqNum(TUint32 aSeq)			  		{ iSeq = aSeq; }
williamr@2:   	inline TTcpSeqNum(const TTcpSeqNum& aSeq)		{ iSeq = aSeq.iSeq; }
williamr@2: 
williamr@2:   	inline TTcpSeqNum& operator=(TUint32 aSeq)		  { iSeq = aSeq; return *this; }
williamr@2:   	inline TTcpSeqNum& operator=(const TTcpSeqNum& aSeq)	  { iSeq = aSeq.iSeq; return *this; }
williamr@2:   	inline TTcpSeqNum& operator+=(TInt aOff)		  { iSeq += aOff; return *this; }
williamr@2:   	inline TTcpSeqNum& operator-=(TInt aOff)		  { iSeq -= aOff; return *this; }
williamr@2: 
williamr@2:   	inline TTcpSeqNum& operator++()			{ ++iSeq; return *this; }
williamr@2:   	inline TTcpSeqNum operator++(TInt)		{ return iSeq++; }
williamr@2:   	inline TTcpSeqNum& operator--()			{ --iSeq; return *this; }
williamr@2:   	inline TTcpSeqNum operator--(TInt)		{ return iSeq--; }
williamr@2: 
williamr@2:   	inline TBool operator==(const TTcpSeqNum& aSeq) const	{ return iSeq == aSeq.iSeq; }
williamr@2:   	inline TBool operator!=(const TTcpSeqNum& aSeq) const	{ return iSeq != aSeq.iSeq; }
williamr@2:   	inline TBool operator<(const TTcpSeqNum& aSeq) const	{ return (TInt32)(iSeq - aSeq.iSeq) < 0; }
williamr@2:   	inline TBool operator<=(const TTcpSeqNum& aSeq) const	{ return (TInt32)(iSeq - aSeq.iSeq) <= 0; }
williamr@2:   	inline TBool operator>(const TTcpSeqNum& aSeq) const	{ return (TInt32)(iSeq - aSeq.iSeq) > 0; }
williamr@2:   	inline TBool operator>=(const TTcpSeqNum& aSeq) const	{ return (TInt32)(iSeq - aSeq.iSeq) >= 0; }
williamr@2:   	inline TTcpSeqNum operator+(TInt aOff) const		  	{ return iSeq + aOff; }
williamr@2:   	inline TTcpSeqNum operator-(TInt aOff) const		  	{ return iSeq - aOff; }
williamr@2:   	inline TInt32 operator-(const TTcpSeqNum& aSeq) const   { return iSeq - aSeq.iSeq; }
williamr@2: 
williamr@2:   	//
williamr@2:   	// Automatic typecast can lead to ambiguous expressions and
williamr@2:   	// in the worst case to some very hard-to-track errors.
williamr@2:   	// We use the following explicit typecast instead. -ML
williamr@2:   	//
williamr@2:   	inline TUint32 Uint32() const				  { return iSeq; }
williamr@2: 	//inline operator TUint32() const			  { return iSeq; }
williamr@2: 
williamr@2:   	// Methods for checking whether a sequence number is inside or outside a given window.
williamr@2:   	inline TBool Inside(TTcpSeqNum aSeqLo, TTcpSeqNum aSeqHi)
williamr@2:     	{ return (iSeq - aSeqLo.iSeq) <= (aSeqHi.iSeq - aSeqLo.iSeq); }
williamr@2: 
williamr@2:   	inline TBool Outside(TTcpSeqNum aSeqLo, TTcpSeqNum aSeqHi)
williamr@2:     	{ return (iSeq - aSeqLo.iSeq) > (aSeqHi.iSeq - aSeqLo.iSeq); }
williamr@2: 
williamr@2: private:
williamr@2:   	TUint32 iSeq;
williamr@2: 	};
williamr@2: 
williamr@2: #endif