/*

* 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:

* Name        : MessageReader.h

* Part of     : SigComp / dispatcher

* Interface   : 

* SigComp message reader

* Version     : 1.0

*

*/

/**

 @internalComponent

*/

#ifndef MESSAGEREADER_H

#define MESSAGEREADER_H

//  INCLUDES

#include <e32base.h>

// CLASS DECLARATION

/**

 * @brief Class for reading from sigcomp message.

 * 

 * @class CMessageReader messagereader.h "messagereader.h"

 *

 * This class is used for reading from sigcomp message with optional 

 * record marker decoding as specified in RFC 3320, chapter 4.2.2

 */

class CMessageReader : public CBase

    {

    public:

        /**

         * Constructs object.

         *

         * @param aMessage message to be read

         * @param aStreamBasedProtocol if ETrue, a message will be record

         *                             marker decoded.

         */

        CMessageReader(const TDesC8& aMessage, TBool aStreamBasedProtocol);

        /**

         * Read one byte from message.

         *

         * @returns If the reading is successful, the value of readed

         *          byte (0-255).

         *          If the reading fails, a negative value indicating 

         *          the cause of failure.

         *          KErrEof if delimiter is reached, or KErrTooBig if 

         *          end of buffer.

         */

        TInt ReadByte(TUint& aByte);

        /**

         * Read block of bytes from message.

         *

         * @param aBlock contains data read from the buffer; on exit, 

         *               its Length() specifies the length of readed

         *               (successful or failed) data.

         * @param aLentgh specifies the amount of data to be read.

         *

         * @returns If the reading is successful, a KErrNone.

         *          If the reading fails, a negative value indicating

         *          the cause of failure.

         *          KErrEof if delimiter is reached, or KErrTooBig if

         *          end of buffer.

         */

        TInt ReadBlock(TDes8& aBlock, TInt aLength);

        /**

         * Read block of bytes from message.

         *

         * @param aBlock contains data read from the buffer; on call, 

         *               its MaxLength()

         *               specifies the amount of data to be read; on exit,

         *               its Length() specifies the length of readed 

         *               (successful or failed) data.

         *

         * @returns If the reading is successful, a KErrNone.

         *          If the reading fails, a negative value indicating the 

         *          cause of failure.

         *          KErrEof if delimiter is reached, or KErrTooBig if end 

         *          of buffer.

         */

        TInt ReadBlock(TDes8& aBlock);

        /**

         * Check if specified number of bytes is available in buffer.

         *

         * @param aLength number of bytes to check

         *

         * @returns If the specified number of bytes is available, a KErrNone.

         *          If not, a negative value indicating the cause of failure.

         *          KErrEof if delimiter is reached, or KErrTooBig if end of 

         *          buffer.

         */

        TInt Avail(TInt aLength);

        /**

         * Get current position in message buffer.

         *

         * @returns position in message buffer.

         */

        TInt Pos();

        /**

         * If stream-based protocol, skip message delimiters.

         *

         * @param aDelToSkip number of delimiters to skip, default maximumm

         *                   possible.

         *

         * @returns KErrNone if seccesfful, error code if failure.

         */

        TInt SkipDelimiters(TUint aDelToSkip=KMaxTUint32);

    private:    // Data

        TPtrC8 iMessage;

        TBool iStreamBasedProtocol;

        TInt iPos;

        TInt iQuoteBytes;

    };

#endif

// End of File