// Copyright (c) 2003-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "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:

// Telnet Protocol API

// Supported RFC class implementations

// 

//

/**

 @file 

*/

#include	"TELFSM.H"

#include	"TELDEBUG.H"

// The option negotiation class

// Independent of the option 

// All option classes contain one of these state machine classes

TOptionFSM::TOptionFSM()

/**

Constructor

Set up the defaults

*/

	{

	Allowed = ENoOption;

	Us = ENo;

	UsQ = EEmpty;

	Him = ENo;

	HimQ = EEmpty;

	}

void TOptionFSM::Reset()

/**

Reset restores the state machine to default but leaves the permissions

*/

	{

	Us = ENo;

	UsQ = EEmpty;

	Him = ENo;

	HimQ = EEmpty;

	}

TInt32	TOptionFSM::Request(const TInt32 aRequest,TInt32& aAction,TInt32& aEvent)

/**

Implementation of RFC 1143 Q Method bidirectional Telnet option state machine

Can be called from the client side (aRequest = EClientXX) or the line side (aRequest = EServerXX).

errors are returned for illegal requests

aEvent is set when an option transits to enabled or disabled

aAction's are the Telnet defined DO, WILL, WONT, DONT

*/

	{

	TInt32 Ret = EErrNone;

	aAction = ENoAction;

	aEvent = ENoEvent;

	switch(aRequest)

		{

//

		case	EServerWill	:

		if(Him == ENo)

			{

			if(Allowed & EServerWill)

				{

				Him = EYes;				

				Ret = EErrNone;

				aEvent = EServerEnabled;

				aAction = ESendDo;

				}

			else

				{

				Ret = EErrNone;

				aEvent = ENoEvent;

				aAction = ESendDont;

				}

			}

		else if(Him == EYes)

			{

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EWantNo && HimQ == EEmpty)

			{

			Him = ENo;

			Ret = EProtocolError;

			aEvent = EServerDisabled;

			aAction = ENoAction;

			}

		else if(Him == EWantNo && HimQ == EOpposite)

			{

			Him = EYes;

			HimQ = EEmpty;

			Ret = EProtocolError;

			aEvent = EServerEnabled;

			aAction = ENoAction;

			}

		else if(Him == EWantYes && HimQ == EEmpty)

			{

			Him = EYes;

			Ret = EErrNone;

			aEvent = EServerEnabled;

			aAction = ENoAction;

			}

		else if(Him == EWantYes && HimQ == EOpposite)

			{

			Him = EWantNo;

			HimQ = EEmpty;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ESendDont;

			}

		break;

//

		case	EServerDo	:

		if(Us == ENo)

			{

			if(Allowed & EServerDo)

				{

				Us = EYes;				

				Ret = EErrNone;

				aEvent = EClientEnabled;

				aAction = ESendWill;

				}

			else

				{

				Ret = EErrNone;

				aEvent = ENoEvent;

				aAction = ESendWont;

				}

			}

		else if(Us == EYes)

			{

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EWantNo && UsQ == EEmpty)

			{

			Us = ENo;

			Ret = EProtocolError;

			aEvent = EClientDisabled;

			aAction = ENoAction;

			}

		else if(Us == EWantNo && UsQ == EOpposite)

			{

			Us = EYes;

			UsQ = EEmpty;

			Ret = EProtocolError;

			aEvent = EClientEnabled;

			aAction = ENoAction;

			}

		else if(Us == EWantYes && UsQ == EEmpty)

			{

			Us = EYes;

			Ret = EErrNone;

			aEvent = EClientEnabled;

			aAction = ENoAction;

			}

		else if(Us == EWantYes && UsQ == EOpposite)

			{

			Us = EWantNo;

			UsQ = EEmpty;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ESendWont;

			}

		break;

//

		case	EServerWont	:

		if(Him == ENo)

			{

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EYes)

			{

			Him = ENo;

			Ret = EErrNone;

			aEvent = EServerDisabled;

			aAction = ESendDont;

			}

		else if(Him == EWantNo && HimQ == EEmpty)

			{

			Him = ENo;

			Ret = EErrNone;

			aEvent = EServerDisabled;

			aAction = ENoAction;

			}

		else if(Him == EWantNo && HimQ == EOpposite)

			{

			Him = EWantYes;

			HimQ = ENone;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ESendDo;

			}

		else if(Him == EWantYes && HimQ == EEmpty)

			{

			Him = ENo;

			Ret = EErrNone;

			aEvent = EServerDisabled;

			aAction = ENoAction;

			}

		else if(Him == EWantYes && HimQ == EOpposite)

			{

			Him = ENo;

			HimQ = ENone;

			Ret = EErrNone;

			aEvent = EServerDisabled;

			aAction = ENoAction;

			}

		break;

//

		case	EServerDont	:

		if(Us == ENo)

			{

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EYes)

			{

			Us = ENo;

			Ret = EErrNone;

			aEvent = EClientDisabled;

			aAction = ESendWont;

			}

		else if(Us == EWantNo && UsQ == EEmpty)

			{

			Us = ENo;

			Ret = EErrNone;

			aEvent = EClientDisabled;

			aAction = ENoAction;

			}

		else if(Us == EWantNo && UsQ == EOpposite)

			{

			Us = EWantYes;

			UsQ = ENone;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ESendWill;

			}

		else if(Us == EWantYes && UsQ == EEmpty)

			{

			Us = ENo;

			Ret = EErrNone;

			aEvent = EClientDisabled;

			aAction = ENoAction;

			}

		else if(Us == EWantYes && UsQ == EOpposite)

			{

			Us = ENo;

			UsQ = ENone;

			Ret = EErrNone;

			aEvent = EClientDisabled;

			aAction = ENoAction;

			}

		break;

//

		case	EClientDo	:

		if(!(Allowed & EClientDo))

			{

			Ret = EPermissionsError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == ENo)

			{

			Him = EWantYes;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ESendDo;

			}

		else if(Him == EYes)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EWantNo && HimQ == EEmpty)

			{

			if(UsQ == EOpposite)

				{

				Ret = EErrNone;

				HimQ = EOpposite;

				}

			else

				Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EWantNo && HimQ == EOpposite)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EWantYes && HimQ == EEmpty)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EWantYes && HimQ == EOpposite)

			{

			HimQ = EEmpty;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		break;

//

		case	EClientWill	:

		if(!(Allowed & EClientWill))

			{

			Ret = EPermissionsError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == ENo)

			{

			Us = EWantYes;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ESendWill;

			}

		else if(Us == EYes)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EWantNo && UsQ == EEmpty)

			{

			if(HimQ == EOpposite)

				{

				Ret = EErrNone;

				UsQ = EOpposite;

				}

			else

				Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EWantNo && UsQ == EOpposite)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EWantYes && UsQ == EEmpty)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EWantYes && UsQ == EOpposite)

			{

			UsQ = EEmpty;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		break;

//

		case	EClientDont	:

		if(Him == ENo)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EYes)

			{

			Him = EWantNo;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ESendDont;

			}

		else if(Him == EWantNo && HimQ == EEmpty)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EWantNo && HimQ == EOpposite)

			{

			HimQ = EEmpty;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EWantYes && HimQ == EEmpty)

			{

			if(UsQ == EOpposite)

				{

				HimQ = EOpposite;

				Ret = EErrNone;

				}

			else

				Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Him == EWantYes && HimQ == EOpposite)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		break;

//

		case	EClientWont	:

		if(Us == ENo)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EYes)

			{

			Us = EWantNo;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ESendWont;

			}

		else if(Us == EWantNo && UsQ == EEmpty)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EWantNo && UsQ == EOpposite)

			{

			UsQ = EEmpty;

			Ret = EErrNone;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EWantYes && UsQ == EEmpty)

			{

			if(HimQ == EOpposite)

				{

				UsQ = EOpposite;

				Ret = EErrNone;

				}

			else

				Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		else if(Us == EWantYes && UsQ == EOpposite)

			{

			Ret = EProtocolError;

			aEvent = ENoEvent;

			aAction = ENoAction;

			}

		break;

		default	:

		break;

		}

	return(Ret);

	}

// The base class for all RFC option classes 

CRFCOptionBase::~CRFCOptionBase()

/**

Destructor

*/

	{

	__FLOG_STATIC(KTelnetLoggingCompnt(),KTelnetLoggingTag(),_L("CRFCOptionBase::D'Tor"));

	}

void CRFCOptionBase::CreateOptionResponse(TInt8 aOption,TInt32 aAction,TDes8& aBuffer)

/**

Create a Telnet protocol request or response

*/

	{

	aBuffer.Append(KTelnetIAC);

	// MAP our local codes to the genuine telnet ones

	if(aAction == TOptionFSM::ESendWill)

		aBuffer.Append(KTelnetWILL);

	else if(aAction == TOptionFSM::ESendDo)

		aBuffer.Append(KTelnetDO);

	else if(aAction == TOptionFSM::ESendDont)

		aBuffer.Append(KTelnetDONT);

	else if(aAction == TOptionFSM::ESendWont)

		aBuffer.Append(KTelnetWONT);

	aBuffer.Append(aOption);

	};

void CUnknownOption::RequestUnknown(TInt8 aOption,const TInt32 aRequest, TDes8& aAction,TInt32& aEvent)

/**

For tidy code we keep a class that handles unknown option requests from the server.

The result of a call into this object will always be WONT or DONT

*/

	{

	TInt32 action;

	iFSM.Request(aRequest,action,aEvent);

	if(action != TOptionFSM::ENoAction)

		CRFCOptionBase::CreateOptionResponse(aOption,action,aAction);

	}

CUnknownOption* CUnknownOption::NewL()

	{

	CUnknownOption* self = new(ELeave) CUnknownOption;