/*
* Copyright (c) 2009 Lukas Mejdrech
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup packet
* @{
*/
/** @file
* Packet header.
*/
#ifndef __NET_PACKET_HEADER_H__
#define __NET_PACKET_HEADER_H__
#include "packet.h"
/** Returns the actual packet data length.
* @param header The packet header. Input parameter.
*/
#define PACKET_DATA_LENGTH( header ) (( header )->data_end - ( header )->data_start )
/** Returns the maximum packet address length.
* @param header The packet header. Input parameter.
*/
#define PACKET_MAX_ADDRESS_LENGTH( header ) (( header )->dest_addr - ( header )->src_addr )
/** Returns the minimum packet suffix.
* @param header The packet header. Input parameter.
*/
#define PACKET_MIN_SUFFIX( header ) (( header )->length - ( header )->data_start - ( header )->max_content )
/** Packet integrity check magic value.
*/
#define PACKET_MAGIC_VALUE 0x11227788
/** Packet header.
*/
struct packet{
/** Packet identifier.
*/
packet_id_t packet_id;
/** Packet queue sorting value.
* The packet queue is sorted the ascending order.
*/
size_t order;
/** Packet metric.
*/
size_t metric;
/** Previous packet in the queue.
*/
packet_id_t previous;
/** Next packet in the queue.
*/
packet_id_t next;
/** Total length of the packet.
* Contains the header, the addresses and the data of the packet.
* Corresponds to the mapped sharable memory block.
*/
size_t length;
/** Stored source and destination addresses length.
*/
size_t addr_len;
/** Souce address offset in bytes from the beginning of the packet header.
*/
size_t src_addr;
/** Destination address offset in bytes from the beginning of the packet header.
*/
size_t dest_addr;
/** Reserved data prefix length in bytes.
*/
size_t max_prefix;
/** Reserved content length in bytes.
*/
size_t max_content;
/** Actual data start offset in bytes from the beginning of the packet header.
*/
size_t data_start;
/** Actual data end offset in bytes from the beginning of the packet header.
*/
size_t data_end;
/** Integrity check magic value.
*/
int magic_value;
};
/** Returns whether the packet is valid.
* @param packet The packet to be checked. Input parameter.
* @returns true if the packet is not NULL and the magic value is correct.
* @returns false otherwise.
*/
static inline int packet_is_valid( const packet_t packet ){
return packet && ( packet->magic_value == PACKET_MAGIC_VALUE );
}
#endif
/** @}
*/