/*

* Copyright (c) 2001-2006 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "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:  EAP and WLAN authentication protocols.

*

*/

#if !defined(_EAP_TLV_HEADER_H_)

#define _EAP_TLV_HEADER_H_

#include "eap_am_types.h"

#include "eap_tools.h"

#include "eap_general_header_base.h"

/** @file */

typedef u32_t eap_tlv_type_t;

const eap_tlv_type_t eap_tlv_type_none = 0ul;

//----------------------------------------------------------------------------

/// This class defines header of Attribute-Value Pairs.

/**

 * Here is a figure of header of Attribute-Value Pairs.

 * Value data follows eap_tlv_header_c.

 * @code

 *  EAP-TLV-header:

 *  0                   1                   2                   3   

 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 

 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 * |                              Type                             |

 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 * |                             Length                            |

 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 * |                              Value...

 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

 * @endcode

 * 

 * @code

 * The fields of this header are:

 * 32-bits Type;                   This is a type of value.

 * 32-bits value length (Length);  This is a length field, the length (in bytes) of the following value.

 * @endcode

 * 

 */

class EAP_EXPORT eap_tlv_header_c

: public eap_general_header_base_c

{

private:

	//--------------------------------------------------

	abs_eap_am_tools_c * const m_am_tools;

	//--------------------------------------------------

protected:

	//--------------------------------------------------

	/// This is enumeration of offsets to data fields.

	enum offsets

	{

		m_type_offset = 0ul,                           ///< This is offset to fags and tlv type 32-bit field.

		m_length_offset = m_type_offset+sizeof(u32_t), ///< This is offset to length 32-bit field.

		m_data_offset = m_length_offset+sizeof(u32_t), ///< This is offset to data field.

	};

	//--------------------------------------------------

public:

	//--------------------------------------------------

	/**

	 * The destructor of the eap_tlv_header_c class does nothing.

	 */

	EAP_FUNC_IMPORT virtual ~eap_tlv_header_c();

	/**

	 * The constructor of the eap_tlv_header_c class simply initializes the attributes.

	 */

	EAP_FUNC_IMPORT eap_tlv_header_c(

		abs_eap_am_tools_c * const tools,

		void * const header_begin,

		const u32_t header_buffer_length);

	/**

	 * This function returns the type.

	 */

	EAP_FUNC_IMPORT eap_tlv_type_t get_type() const;

	/**

	 * This function returns the data length of value.

	 */

	EAP_FUNC_IMPORT u32_t get_value_length() const;

	/**

	 * This function returns the header length of TLV.

	 */

	EAP_FUNC_IMPORT static u32_t get_header_length();

	/**

	 * This function returns pointer to the offset of value.

	 * @param offset is the offset of queried data in bytes.

	 * @param contignuous_bytes is the length of queried data in bytes.

	 */

	EAP_FUNC_IMPORT u8_t * get_value_offset(const u32_t offset, const u32_t contignuous_bytes) const;

	/**

	 * This function returns pointer to begin of value.

	 * @param contignuous_bytes is the length of queried data in bytes.

	 */

	EAP_FUNC_IMPORT u8_t * get_value(const u32_t contignuous_bytes) const;

	/**

	 * This function checks the header is valid.

	 */

	EAP_FUNC_IMPORT eap_status_e check_header() const;

	/**

	 * This function returns the type.

	 */

	EAP_FUNC_IMPORT eap_status_e set_type(const eap_tlv_type_t type);

	/**

	 * This function sets the value length.

	 */

	EAP_FUNC_IMPORT eap_status_e set_value_length(const u32_t value_length);

	/**

	 * This function resets the TLV header.

	 */

	EAP_FUNC_IMPORT eap_status_e reset_header(

		const eap_tlv_type_t type,

		const u32_t value_length);

	// 

	//--------------------------------------------------

}; // class eap_tlv_header_c

//--------------------------------------------------

#endif //#if !defined(_EAP_TLV_HEADER_H_)

// End.