/*
* 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 map and queue.
*/
#ifndef __NET_PACKET_H__
#define __NET_PACKET_H__
/** Packet identifier type.
* Value zero (0) is used as an invalid identifier.
*/
typedef int packet_id_t;
/** Type definition of the packet.
* @see packet
*/
typedef struct packet * packet_t;
/** Type definition of the packet pointer.
* @see packet
*/
typedef packet_t * packet_ref;
/** Type of the received packet.
*/
enum packet_type{
/** The packet is from the local subsystem.
*/
PACKET_SELF,
/** The packet is for all hosts.
*/
PACKET_BROADCAST,
/** The packet target complies with the local subsystem filter.
*/
PACKET_MULTICAST,
/** The packet is for the local subsystem from other host.
*/
PACKET_OTHERHOST
};
/** Finds the packet mapping.
* @param packet_id The packet identifier to be found. Input parameter.
* @returns The found packet reference.
* @returns NULL if the mapping does not exist.
*/
packet_t pm_find( packet_id_t packet_id );
/** Adds the packet mapping.
* @param packet The packet to be remembered. Input parameter.
* @returns EOK on success.
* @returns EINVAL if the packet is not valid.
* @returns EINVAL if the packet map is not initialized.
* @returns ENOMEM if there is not enough memory left.
*/
int pm_add( packet_t packet );
/** Initializes the packet map.
* @returns EOK on success.
* @returns ENOMEM if there is not enough memory left.
*/
int pm_init( void );
/** Releases the packet map.
*/
void pm_destroy( void );
/** Add packet to the sorted queue.
* The queue is sorted in the ascending order.
* The packet is inserted right before the packets of the same order value.
* @param first The first packet of the queue. May be NULL. Input parameter.
* @param packet The packet to be added. Input parameter.
* @param order The packet order value. Input parameter.
* @param metric The metric value of the packet. Input parameter.
* @returns The first packet of the queue. The original first packet may be shifted by the new packet.
* @returns NULL if the packet is not valid.
*/
packet_t pq_add( packet_t first, packet_t packet, int order, size_t metric );
/** Inserts packet after the given one.
* @param packet The packet in the queue. Input parameter.
* @param new_packet The new packet to be inserted.
* @returns EOK on success.
* @returns EINVAL if etiher of the packets is invalid.
*/
int pq_insert_after( packet_t packet, packet_t new_packet );
/** Detach the packet from the queue.
* @param packet The packet to be detached. Input parameter.
* @returns The next packet in the queue. If the packet is the first one of the queue, this becomes the new first one.
* @returns NULL if there is no packet left.
* @returns NULL if the packet is not valid.
*/
packet_t pq_detach( packet_t packet );
/** Sets the packet order and metric attributes.
* @param packet The packet to be set. Input parameter.
* @param order The packet order value. Input parameter.
* @param metric The metric value of the packet. Input parameter.
*/
int pq_set( packet_t packet, int order, size_t metric );
/** Releases the whole queue.
* Detaches all packets of the queue and calls the packet_release() for each of them.
* @param first The first packet of the queue. Input parameter.
* @param packet_release The releasing function called for each of the packets after its detachment. Input parameter.
*/
void pq_destroy( packet_t first, void ( * packet_release )( packet_t packet ));
/** Returns the next packet in the queue.
* @param packet The packet queue member. Input parameter.
* @returns The next packet in the queue.
* @returns NULL if there is no next packet.
* @returns NULL if the packet is not valid.
*/
packet_t pq_next( packet_t packet );
/** Returns the previous packet in the queue.
* @param packet The packet queue member. Input parameter.
* @returns The previous packet in the queue.
* @returns NULL if there is no previous packet.
* @returns NULL if the packet is not valid.
*/
packet_t pq_previous( packet_t packet );
#endif
/** @}
*/