// Copyright (c) 2008-2009 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 "browsingframe.h"

/** Verifies the length of a frame is correct.  Checking:

1) Header is present

2) Data length indicated is present

This does not semantically check that the data expected for

the PDU ID is present.

@param aFrame The frame to verify

@leave KErrCorrupt if the length of the frame is incorrect

*/

void AvrcpBrowsing::BrowsingFrame::VerifyFrameL(const TDesC8& aFrame)

	{

	if((aFrame.Length() < AvrcpBrowsing::KHeaderLength) ||

	  (aFrame.Length() < (AvrcpBrowsing::KHeaderLength + ParamLength(aFrame))))

		{

		User::Leave(KErrCorrupt);

		}

	}

/** Retreives the PDU ID from this frame.

@pre The integrity of the frame must have been verified (@see 

	 BrowsingFrame::VerifyFrameL) as the length is not checked

	 before retrieving the PDU ID.

@param aFrame The frame to retrieve the PDU ID for.

@return The PDU ID of aFrame

*/

AvrcpBrowsing::TPduId AvrcpBrowsing::BrowsingFrame::PduId(const TDesC8& aFrame)

	{

	return aFrame[0];

	}

/** Retreives the parameter length from this frame.

@pre The integrity of the frame must have been verified (@see 

	 BrowsingFrame::VerifyFrameL) as the length is not checked

	 before retrieving the parameter length.

@param aFrame The frame to retrieve the parameter length for.

@return The parameter length of aFrame

*/

TInt AvrcpBrowsing::BrowsingFrame::ParamLength(const TDesC8& aFrame)

	{

	TInt paramLength = 0;

	paramLength += aFrame[2];

	paramLength += ((TUint)aFrame[1]) << 8;

	return paramLength;

	}

/** Retreives the payload from this frame.

@pre The integrity of the frame must have been verified (@see 

	 BrowsingFrame::VerifyFrameL) as the length is not checked

	 before retrieving the payload.

@param aFrame The frame to retrieve the payload for.

@param aPayload On return the payload of aFrame

*/

void AvrcpBrowsing::BrowsingFrame::Payload(const TDesC8& aFrame, TPtrC8& aPayload)

	{

	aPayload.Set(aFrame.Mid(AvrcpBrowsing::KHeaderLength, AvrcpBrowsing::BrowsingFrame::ParamLength(aFrame)));

	}