nes-proj/core/net/ipv4/uaodv-rt.c

147 lines
4.1 KiB
C

/*
* Copyright (c) 2006, Swedish Institute of Computer Science.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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.
*
* This file is part of the Contiki operating system.
*
*/
/**
* \file
* Routing tables for the micro implementation of the AODV ad hoc routing protocol
* \author
* Adam Dunkels <adam@sics.se>
*/
#include "net/ipv4/uaodv-rt.h"
#include "contiki-net.h"
#ifndef UAODV_NUM_RT_ENTRIES
#define UAODV_NUM_RT_ENTRIES 8
#endif
/*
* LRU (with respect to insertion time) list of route entries.
*/
LIST(route_table);
MEMB(route_mem, struct uaodv_rt_entry, UAODV_NUM_RT_ENTRIES);
/*---------------------------------------------------------------------------*/
void
uaodv_rt_init(void)
{
list_init(route_table);
memb_init(&route_mem);
}
/*---------------------------------------------------------------------------*/
struct uaodv_rt_entry *
uaodv_rt_add(uip_ipaddr_t *dest, uip_ipaddr_t *nexthop,
unsigned hop_count, const uint32_t *seqno)
{
struct uaodv_rt_entry *e;
/* Avoid inserting duplicate entries. */
e = uaodv_rt_lookup_any(dest);
if(e != NULL) {
list_remove(route_table, e);
} else {
/* Allocate a new entry or reuse the oldest. */
e = memb_alloc(&route_mem);
if(e == NULL) {
e = list_chop(route_table); /* Remove oldest entry. */
}
}
uip_ipaddr_copy(&e->dest, dest);
uip_ipaddr_copy(&e->nexthop, nexthop);
e->hop_count = hop_count;
e->hseqno = uip_ntohl(*seqno);
e->is_bad = 0;
/* New entry goes first. */
list_push(route_table, e);
return e;
}
/*---------------------------------------------------------------------------*/
struct uaodv_rt_entry *
uaodv_rt_lookup_any(uip_ipaddr_t *dest)
{
struct uaodv_rt_entry *e;
for(e = list_head(route_table); e != NULL; e = e->next) {
if(uip_ipaddr_cmp(dest, &e->dest)) {
return e;
}
}
return NULL;
}
struct uaodv_rt_entry *
uaodv_rt_lookup(uip_ipaddr_t *dest)
{
struct uaodv_rt_entry *e;
e = uaodv_rt_lookup_any(dest);
if(e != NULL && e->is_bad)
return NULL;
return e;
}
/*---------------------------------------------------------------------------*/
#if 0
void
uaodv_rt_remove(struct uaodv_rt_entry *e)
{
list_remove(route_table, e);
memb_free(&route_mem, e);
}
#endif
void
uaodv_rt_lru(struct uaodv_rt_entry *e)
{
if(e != list_head(route_table)) {
list_remove(route_table, e);
list_push(route_table, e);
}
}
/*---------------------------------------------------------------------------*/
void
uaodv_rt_flush_all(void)
{
struct uaodv_rt_entry *e;
while (1) {
e = list_pop(route_table);
if(e != NULL)
memb_free(&route_mem, e);
else
break;
}
}