// Copyright (c) 2001-2009 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:

//

#include <bluetooth/logger.h>

#include <e32base.h>

#include "rfcommutil.h"

#include "rfcommmuxer.h"

#include "rfcommflow.h"

#ifdef __FLOG_ACTIVE

_LIT8(KLogComponent, LOG_COMPONENT_RFCOMM);

#endif

/*************************************************************************/

CRfcommFlowStrategyFactory::CRfcommFlowStrategyFactory()

	{

	LOG_FUNC

//	iFlowStrategies.Reset();  // Null all the pointers -- not necessary as array is in CBase class.

	}

CRfcommFlowStrategyFactory::~CRfcommFlowStrategyFactory()

	{

	LOG_FUNC

	// Destroy all the state objects

	iFlowStrategies.DeleteAll();

	}

CRfcommFlowStrategyFactory* CRfcommFlowStrategyFactory::NewL()

	{

	LOG_STATIC_FUNC

	CRfcommFlowStrategyFactory* factory  = new (ELeave) CRfcommFlowStrategyFactory();

	CleanupStack::PushL(factory);

	// Create all the new states

	factory->iFlowStrategies[EFlowInitial]  = new (ELeave) TRfcommFlowStrategyInitial(factory);

	factory->iFlowStrategies[EFlowCreditBased] = new (ELeave) TRfcommFlowStrategyCreditBased(factory);

	factory->iFlowStrategies[EFlowNonCreditBased] = new (ELeave) TRfcommFlowStrategyNonCreditBased(factory);

	// etc...

	CleanupStack::Pop();

	return factory;

	}

TRfcommFlowStrategy& CRfcommFlowStrategyFactory::GetFlowStrategy(const TFlowStrategies aFlowStrategy) const

	{

	LOG_FUNC

	__ASSERT_DEBUG(aFlowStrategy != EMaxFlowStrategy, Panic(ERfCommFlowStrategyOutOfBounds));

	return *iFlowStrategies[aFlowStrategy];

	}

/*************************************************************************/

TRfcommFlowStrategy::TRfcommFlowStrategy(CRfcommFlowStrategyFactory* aFactory)

:iFactory(aFactory)

	{

	LOG_FUNC

	//iFactory = aFactory;

	}

TRfcommFlowStrategy::~TRfcommFlowStrategy()

	{

	LOG_FUNC

	}

TRfcommFlowStrategyInitial::TRfcommFlowStrategyInitial(CRfcommFlowStrategyFactory* aFactory)

:TRfcommFlowStrategy(aFactory) 

	{

	LOG_FUNC

	}

TRfcommFlowStrategyInitial::~TRfcommFlowStrategyInitial()

	{

	LOG_FUNC

	}

TInt TRfcommFlowStrategyInitial::DataBufferMultiple()

	{

	LOG_FUNC

	return KRfcommSAPBufferMultiple;

	};

TUint16 TRfcommFlowStrategyInitial::UsableMTU(const CRfcommSAP& aSAP, TUint8 /*aCredit*/) const

	/**

	  Available frame space for data

	**/

	{

	LOG_FUNC

	__ASSERT_DEBUG(aSAP.NegotiatedMTU(), Panic(ERfcommBadCalculatedMTU));

	return aSAP.NegotiatedMTU();

	}

TBool TRfcommFlowStrategyInitial::AllowWrite(CRfcommSAP& /*aSAP*/)

	/**

	  Ignore CBFC Credits

	**/

	{

	LOG_FUNC

	return ETrue;

	}

TBool TRfcommFlowStrategyInitial::AllowFCOnOff(TBool /*aCommand*/)

	/**

	  Always allow 'FC On/Off' commands (not be confused with FC bit in an MSC command!).

	**/

	{

	LOG_FUNC

	return ETrue;

	}

TInt TRfcommFlowStrategyInitial::PNConvergenceLayer(TBool aCommand)

	/**

	  We are negotiating so keep trying for CBFC.

	**/

	{

	LOG_FUNC

	return aCommand?KCBFCCommandFlag:KCBFCResponseFlag;

	}

TUint8 TRfcommFlowStrategyInitial::PNFinalOctet() // FIXME: Rename to InitialCredit()

	/**

	  We are negotiating so keep trying for CBFC.

	**/

	{

	LOG_FUNC

	return KInitialCredit;

	}

TUint8 TRfcommFlowStrategyInitial::WriteCredit(CRfcommSAP& /*aSAP*/)

	/**

	  Return number of CBFC credits to send in UIH frame.

	**/

	{

	LOG_FUNC

	return 0;

	}

void TRfcommFlowStrategyInitial::OutgoingMSCReviseSignals(TBool /*aCommand*/, TUint8& /*aSignals*/)

	/**

	  Only requires action for CBFC.

	**/

	{

	LOG_FUNC

	}

void TRfcommFlowStrategyInitial::ReviseDonatedCredits(CRfcommSAP& /*aSAP*/, TUint8 /*aCredit*/)

	/**

	  Only requires action for CBFC.

	**/

	{

	LOG_FUNC

	}

void TRfcommFlowStrategyInitial::ReviseTransmittedCredits(CRfcommSAP& /*aSAP*/)

	{

	LOG_FUNC

	/**

	  Only requires action for CBFC.

	**/

	}

CRfcommDataFrame* TRfcommFlowStrategyInitial::NewDataFrame(CRfcommMuxer& aMuxer, 

													 TUint8 aAddr, 

												     TInt aLen, 

#ifdef _DEBUG

												     TUint8 aCredit,

#else

												     TUint8 /*aCredit*/,

#endif

												     CRfcommSAP* aSAP)

	/**

	   Returns a new data (UIH) frame for the specified DLCI

	   The C/R bit for the UIH frame is always 1 for the initiator and

	   0 for the responder, which is the same as for commands.

	**/

	{

	LOG_FUNC

	__ASSERT_DEBUG(!aCredit, Panic(ERfcommUnexpectedCBFCCredit));

	CRfcommDataFrame* frm=NULL;

	TRAPD(err, frm=CRfcommDataFrame::NewL(aLen, aMuxer, aSAP));

	if(!err)

		{

		frm->SetAddress(aAddr);

		frm->SetControl(KUIHCtrlField);

		}

	return frm;	//	NB should be NULL if CRfcommDataFrame was not created

	}

TBool TRfcommFlowStrategyInitial::CanProcessNewData(const TBool aAllowProcessNewData) const

	/**

	  If a SAP's buffer becomes too full, then that SAP will cause the muxer

	  to block any further intake of data. 'aSAPNoFreeSpaceMask' points to the

	  relevant muxer flag.

	**/

	{

	LOG_FUNC

	return aAllowProcessNewData;

	}

void TRfcommFlowStrategyInitial::DecodeLength(TBool /*aCBFC*/, 

										 	  TDesC8& /*aPacket*/, 

											  TInt& /*aCreditBuffer*/, 

											  TInt& /*aHeaderLengthBuffer*/)

	/**

	  Do nothing - not CBFC.

	**/

	{

	LOG_FUNC

	}

TBool TRfcommFlowStrategyInitial::ProcessDataFrameReviseCredits(CRfcommSAP& /*aSAP*/, 

													   TBool /*aPoll*/,

													   TUint8 /*aCredit*/)

	/**

	  Not CBFC - return false => do nothing.

	**/

	{

	LOG_FUNC

	return EFalse;

	}

TBool TRfcommFlowStrategyInitial::MSC(CRfcommSAP& aSAP, TUint8 aSignals)

	/**

	  Respond to flow control aspects of an MSC signal.

	**/

	{

	LOG_FUNC

	// Set CTS. We're clear to send if flow control is off so this 

	// is the inverse of the Flow Control bit

	aSAP.CTS(!(aSignals & KModemSignalFC));

	if(aSAP.CTS())

		{

		// Unblock ESOCK to try again (which might block again!)

		return ETrue;

		}

	return EFalse;

	}

void TRfcommFlowStrategyInitial::UpdateRxFlowControlState(CRfcommSAP& aSAP)

	/**

		Do non-CBFC flow control.

	**/

	{

	LOG_FUNC

	if(aSAP.DataBuffer().Count() + aSAP.Mux()->GetMaxDataSize() <=

	   aSAP.DataBuffer().Length())

		{

		// Let the mux know we can take more data

		//FC

		aSAP.Mux()->SetCanHandleData(aSAP, ETrue);

		}

	if(aSAP.DataBuffer().Count() <= aSAP.LowTideMark())

		{

		if(!aSAP.CTR())

			{

			// We should send a flow on since we've sent an off

			//FC

			TUint8 signals=aSAP.Signals();

			signals &= (~KModemSignalFC);

			TInt result=aSAP.Mux()->SendMSC(aSAP, signals);

			if(result == KErrNone)

				{

				// Update state if we sent it, otherwise don't

				aSAP.SetSignals(signals);

				aSAP.CTR(ETrue);

				}

			//

			}

		}

	}

TBool TRfcommFlowStrategyInitial::NewDataReviseCredits(CRfcommSAP& /*aSAP*/, const TDesC8& /*aData*/)

	/**

		Do nothing - SAPWise (CBFC) only.

	**/

	{

	LOG_FUNC

	return ETrue;

	}

void TRfcommFlowStrategyInitial::NewData(CRfcommSAP& aSAP)

	/**

		Deal with flow control when new data is coming in and CBFC is not on.

	**/

	{

	LOG_FUNC

	if(aSAP.DataBuffer().Count() + aSAP.Mux()->GetMaxDataSize() >=

	   aSAP.DataBuffer().Length())

		/**

			N.B. CircularBuffers: Length() is MaxLength() and Count() is Length()!

		**/

		{

		//Tell the mux we canna take any more, capt'n

		aSAP.Mux()->SetCanHandleData(aSAP, EFalse);

		}

	if(aSAP.DataBuffer().Count() >= aSAP.HighTideMark())

		{

		// Now try to send a flow off, if we haven't already

		if(aSAP.CTR())

			{

			//FC

			TUint8 signals=aSAP.Signals();

			signals |= KModemSignalFC;

			TInt result=aSAP.Mux()->SendMSC(aSAP, signals);

			if(result == KErrNone)

				{

				// we sent it, so update state

				aSAP.SetSignals(signals);

				aSAP.CTR(EFalse);

				}

			//

			}

		}

	return;

	}

CRfcommFlowStrategyFactory::TFlowStrategies TRfcommFlowStrategyInitial::FlowType()

	{

	LOG_FUNC

	return CRfcommFlowStrategyFactory::EFlowInitial;

	}

TRfcommFlowStrategyCreditBased::TRfcommFlowStrategyCreditBased(CRfcommFlowStrategyFactory* aFactory)

:TRfcommFlowStrategyInitial(aFactory) 

	{

	LOG_FUNC

	}

TRfcommFlowStrategyCreditBased::~TRfcommFlowStrategyCreditBased()

	{

	LOG_FUNC

	}

TInt TRfcommFlowStrategyCreditBased::DataBufferMultiple()

	{

	LOG_FUNC

	return KRfcommSAPCBFCBufferMultiple;

	};

TUint16 TRfcommFlowStrategyCreditBased::UsableMTU(const CRfcommSAP& aSAP, TUint8 aCredit) const

	/**

	  Available frame space for data

	**/

	{

	LOG_FUNC

	__ASSERT_DEBUG(aSAP.NegotiatedMTU(), Panic(ERfcommBadCalculatedMTU));

	//Allow for possible credit in header.

	return (STATIC_CAST(TUint16, (aSAP.NegotiatedMTU() - (aCredit?1:0))));

	}

TBool TRfcommFlowStrategyCreditBased::AllowWrite(CRfcommSAP& aSAP)

	/**

	**/

	{

	LOG_FUNC

	return aSAP.LocalCredit();

	}

TBool TRfcommFlowStrategyCreditBased::AllowFCOnOff(TBool aCommand)

	/**

	  Allow responses only. Do not transmit an 'FC On/Off' command.

	  (not be confused with FC bit in an MSC command!)

	**/

	{

	LOG_FUNC

	return !aCommand; //N.B. Reverse logic - if command then return 'EFalse'

	}

TUint8 TRfcommFlowStrategyCreditBased::WriteCredit(CRfcommSAP& aSAP)

	/**

	  Return number of CBFC credits to send in UIH frame

	**/

	{

	LOG_FUNC

	return aSAP.FreeCredit();

	}

void TRfcommFlowStrategyCreditBased::OutgoingMSCReviseSignals(TBool aCommand, TUint8& aSignals)

	/**

	  There is a bit that when zero => CTS should be set to true. 

	  For CBFC this bit must always be zero if we are sending a command. 

	  Thus we are masking that part of an MSC command which tells the remote 

	  to switch its CTS off (and so stop sending). 

	  Required by SPEC.

	**/

	{

	LOG_FUNC

	if(aCommand)

		aSignals &= (~KModemSignalFC);

	}

void TRfcommFlowStrategyCreditBased::ReviseDonatedCredits(CRfcommSAP& aSAP, TUint8 aCredit)

	/**

	  Revise proxy credit (our knowledge of remote credit) upwards by 'aCredit'.

	**/

	{

	LOG_FUNC

	//credit change

	//Increase proxy credit by 'aCredit'.

	aSAP.ProxyForRemoteCreditAddCredit(aCredit);

	}

void TRfcommFlowStrategyCreditBased::ReviseTransmittedCredits(CRfcommSAP& aSAP)

	/**

	  Revise our own credits downward by one.

	  Revise proxy credit (our knowledge of remote credit) upwards by 'aCredit'.

	**/

	{

	LOG_FUNC

	//Decrement allowed transmission credits.

	aSAP.LocalCreditDecrement();

	}

CRfcommDataFrame* TRfcommFlowStrategyCreditBased::NewDataFrame(CRfcommMuxer& aMuxer, 

												   TUint8 aAddr, 

												   TInt aLen, 

												   TUint8 aCredit,

												   CRfcommSAP* aSAP)

	/**

	   Returns a new data (UIH) frame for the specified DLCI

	   The C/R bit for the UIH frame is always 1 for the initiator and

	   0 for the responder, which is the same as for commands.

	**/

	{

	LOG_FUNC

	CRfcommDataFrame* frm=NULL;

	TInt err = 0;

	if(aCredit)

		{

		TRAP(err, frm=CRfcommCreditDataFrame::NewL(aLen, aMuxer, aSAP));

		if(!err)

			{

			frm->SetAddress(aAddr);

			frm->SetControl(KUIHCBFCCtrlField); //FIXME - redone later

			((CRfcommCreditDataFrame*)frm)->SetCredit(aCredit);

			}

		}

	else

		{

		TRAP(err, frm=CRfcommDataFrame::NewL(aLen, aMuxer, aSAP));

		if(!err)

			{

			frm->SetAddress(aAddr);

			frm->SetControl(KUIHCtrlField); //FIXME - redone later ... Poll bit always 0 for UIH

			}

		}

	return frm;	//	NB should be NULL if CRfcommDataFrame was not created

	}

TBool TRfcommFlowStrategyCreditBased::CanProcessNewData(const TBool /*aAllowProcessNewData*/) const

	/**

	  CBFC is on (=>SAP wise flow control). This function is for MUX wide 

	  flow control, and so should ignore all flags and never block here.

	**/

	{

	LOG_FUNC

	return ETrue;

	}

void TRfcommFlowStrategyCreditBased::DecodeLength(TBool aCBFC, 

											      TDesC8& aPacket, 

											      TInt& aCreditBuffer, 

											      TInt& aHeaderLengthBuffer)

	/**

		Provides the credit buffer with the sent credit, and revises the

		header length buffer to take credit byte into account.

	**/

	{

	LOG_FUNC

	TInt cIndex = ((aPacket)[2] & 1)?3:4;

	if (aCBFC)

		{

		aCreditBuffer = aPacket[cIndex];

		aHeaderLengthBuffer++;	// data is 1 byte smaller

		LOG1(_L("RFCOMM: Incoming packet: value in credit field is %d"), aCreditBuffer);

		}

	else

		{

		LOG(_L("RFCOMM: No credit field in incoming packet"));

		}

	}

TBool TRfcommFlowStrategyCreditBased::ProcessDataFrameReviseCredits(CRfcommSAP& aSAP, 

													   TBool aPoll,

													   TUint8 aCredit)

	/**

	   Add 'aCredit' (discovered in incoming data frame)to our credit.

	   If as a result we have credits when non had previously existed, 

	   return true to unblock SAP.

	**/

	//credit change

	{

	LOG_FUNC

	LOG(_L("CRfcommFlowSAPWise::ProcessDataFrameReviseCredits"));

	if (aPoll)

		{

		TBool isUnblock = (!(aSAP.LocalCredit()) && aCredit)?ETrue:EFalse;