// Copyright (c) 2004-2009 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:

// Decodes domain names within protocol messages as specified in:

// "RFC 1035 - Domain names - implementation and specification"

// 

//

/**

 @file DomainNameDecoder.cpp

 @internalTechnology

*/

#include "DomainNameDecoder.h"

void CDomainNameCodec::EncodeL(TDomainNameArray& aNames, RBuf8& aBuf8)

	{

	TUint requiredLength = 0;

	TUint8 nameIdx = 0;

	for (nameIdx=0;nameIdx<aNames.Count();nameIdx++)

		{

		// The total length required for the labels that comprise an

		// individual domain name needs to take into the length octet

		// for the initial label and the null-termination character.

		// Hence the '+ 2' below.

		requiredLength += (aNames[nameIdx].Length() + 2);		

		// A further length check is performed on each domain name to

		// ensure it does not exceed the maximum length permitted according

		// to RFC 1035.

		if(aNames[nameIdx].Length() > KMaxDomainNameLength)

			{

			User::Leave(KErrArgument);

			}

		}		

	aBuf8.Zero();

	aBuf8.ReAllocL(requiredLength);

	TLex8 domainName;

	TPtrC8 currentLabel;

	for (nameIdx=0;nameIdx<aNames.Count();nameIdx++)

		{

		domainName.Assign(aNames[nameIdx]);		

		domainName.Mark();

		while (!domainName.Eos())

			{

			TChar ch;

			do

				{

				ch = domainName.Get();

				}

			while ( ch != TChar('.') && !domainName.Eos() );

			// if not the end of the string, unget the previous char to skip the trailing

			//  dot in our marked token

			//

			if( !domainName.Eos() )

				{

				domainName.UnGet();

				}

			currentLabel.Set(domainName.MarkedToken());

			// move past the dot again, or do nothing in particular at EOS

			//

			domainName.Get();

			User::LeaveIfError(currentLabel.Length() > KMaxDnsLabelLength ? 

				KErrArgument : KErrNone);

			aBuf8.Append(TChar(currentLabel.Length()));

			aBuf8.Append(currentLabel);

			domainName.Mark();

			}

		aBuf8.Append(TChar(0));

		}

	}

void CDomainNameCodec::DecodeL(TPtr8& aInDes)

	{

	TDomainName domainName;

	TUint8* pChar = const_cast<TUint8*>(aInDes.Ptr());

	TUint listLength = aInDes.Length();

	TUint8 labelLength = 0;

	// Walk the list of domain names

	while(pChar < aInDes.Ptr() + listLength)

		{

		domainName.Zero();

		while(*pChar++ != NULL)

			{

			if(domainName.Length() > 0)

				{

				domainName.Append('.');

				}

			labelLength = *(pChar - 1);

			// The two highest order bits must be clear

			User::LeaveIfError(labelLength & 0xC0 ? KErrArgument : KErrNone);

			// Add in the label data

			domainName.Append(pChar, labelLength);

			// Advance the pointer to the next length value

			pChar += labelLength;

			}

		iDomainList.Append(domainName);

		}

	}

CDomainNameCodec::~CDomainNameCodec()

	{

	iDomainList.Close();

	}