contiki/core/net/rime/neighbor.c

342 lines
9.5 KiB
C

/**
* \addtogroup rimeneighbor
* @{
*/
/*
* 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.
*
* $Id: neighbor.c,v 1.22 2010/02/03 20:38:33 adamdunkels Exp $
*/
/**
* \file
* Radio neighborhood management
* \author
* Adam Dunkels <adam@sics.se>
*/
#include <limits.h>
#include <stdio.h>
#include "contiki.h"
#include "lib/memb.h"
#include "lib/list.h"
#include "net/rime/neighbor.h"
#include "net/rime/ctimer.h"
#include "net/rime/collect.h"
#ifdef NEIGHBOR_CONF_MAX_NEIGHBORS
#define MAX_NEIGHBORS NEIGHBOR_CONF_MAX_NEIGHBORS
#else /* NEIGHBOR_CONF_MAX_NEIGHBORS */
#define MAX_NEIGHBORS 8
#endif /* NEIGHBOR_CONF_MAX_NEIGHBORS */
#define RTMETRIC_MAX COLLECT_MAX_DEPTH
MEMB(neighbors_mem, struct neighbor, MAX_NEIGHBORS);
LIST(neighbors_list);
/*static struct neighbor neighbors[MAX_NEIGHBORS];*/
static struct ctimer t;
static int max_time = 120;
#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif
/*---------------------------------------------------------------------------*/
static void
periodic(void *ptr)
{
struct neighbor *n, *next;
/* Go through all neighbors and remove old ones. */
for(n = list_head(neighbors_list); n != NULL; n = next) {
next = NULL;
/* for(i = 0; i < MAX_NEIGHBORS; ++i) {*/
if(!rimeaddr_cmp(&n->addr, &rimeaddr_null) &&
n->time < max_time) {
n->time++;
if(n->time == max_time) {
n->rtmetric = RTMETRIC_MAX;
PRINTF("%d.%d: removing old neighbor %d.%d\n",
rimeaddr_node_addr.u8[0],rimeaddr_node_addr.u8[1],
n->addr.u8[0], n->addr.u8[1]);
rimeaddr_copy(&n->addr, &rimeaddr_null);
next = n->next;
list_remove(neighbors_list, n);
memb_free(&neighbors_mem, n);
}
}
if(next == NULL) {
next = n->next;
}
}
/* PRINTF("neighbor periodic\n");*/
ctimer_set(&t, CLOCK_SECOND, periodic, NULL);
}
/*---------------------------------------------------------------------------*/
void
neighbor_init(void)
{
static uint8_t initialized = 0;
if(initialized == 0) {
initialized = 1;
memb_init(&neighbors_mem);
list_init(neighbors_list);
ctimer_set(&t, CLOCK_SECOND, periodic, NULL);
}
}
/*---------------------------------------------------------------------------*/
struct neighbor *
neighbor_find(const rimeaddr_t *addr)
{
struct neighbor *n;
for(n = list_head(neighbors_list); n != NULL; n = n->next) {
if(rimeaddr_cmp(&n->addr, addr)) {
return n;
}
}
return NULL;
}
/*---------------------------------------------------------------------------*/
void
neighbor_update(struct neighbor *n, uint8_t rtmetric)
{
if(n != NULL) {
n->rtmetric = rtmetric;
n->time = 0;
}
}
/*---------------------------------------------------------------------------*/
void
neighbor_timedout_etx(struct neighbor *n, uint8_t etx)
{
if(n != NULL) {
n->etxs[n->etxptr] += etx;
if(n->etxs[n->etxptr] > RTMETRIC_MAX / NEIGHBOR_ETX_SCALE) {
n->etxs[n->etxptr] = RTMETRIC_MAX / NEIGHBOR_ETX_SCALE;
}
n->etxptr = (n->etxptr + 1) % NEIGHBOR_NUM_ETXS;
}
}
/*---------------------------------------------------------------------------*/
void
neighbor_update_etx(struct neighbor *n, uint8_t etx)
{
if(n != NULL) {
n->etxs[n->etxptr] = etx;
n->etxptr = (n->etxptr + 1) % NEIGHBOR_NUM_ETXS;
n->time = 0;
}
}
/*---------------------------------------------------------------------------*/
uint8_t
neighbor_etx(struct neighbor *n)
{
int i, etx;
etx = 0;
for(i = 0; i < NEIGHBOR_NUM_ETXS; ++i) {
etx += n->etxs[i];
}
return NEIGHBOR_ETX_SCALE * etx / NEIGHBOR_NUM_ETXS;
}
/*---------------------------------------------------------------------------*/
void
neighbor_add(const rimeaddr_t *addr, uint8_t nrtmetric, uint8_t netx)
{
uint16_t rtmetric;
uint16_t etx;
struct neighbor *n, *max;
int i;
PRINTF("neighbor_add: adding %d.%d\n", addr->u8[0], addr->u8[1]);
/* Check if the neighbor is already on the list. */
for(n = list_head(neighbors_list); n != NULL; n = n->next) {
if(rimeaddr_cmp(&n->addr, &rimeaddr_null) ||
rimeaddr_cmp(&n->addr, addr)) {
PRINTF("neighbor_add: already on list %d.%d\n", addr->u8[0], addr->u8[1]);
break;
}
}
/* If the neighbor was not on the list, we try to allocate memory
for it. */
if(n == NULL) {
PRINTF("neighbor_add: not on list, allocating %d.%d\n", addr->u8[0], addr->u8[1]);
n = memb_alloc(&neighbors_mem);
if(n != NULL) {
list_add(neighbors_list, n);
}
}
/* If we could not allocate memory, we try to recycle an old
neighbor */
if(n == NULL) {
PRINTF("neighbor_add: not on list, not allocated, recycling %d.%d\n", addr->u8[0], addr->u8[1]);
/* Find the first unused entry or the used entry with the highest
rtmetric and highest etx. */
rtmetric = 0;
etx = 0;
max = NULL;
for(n = list_head(neighbors_list); n != NULL; n = n->next) {
if(!rimeaddr_cmp(&n->addr, &rimeaddr_null)) {
if(n->rtmetric > rtmetric) {
rtmetric = n->rtmetric;
etx = neighbor_etx(n);
max = n;
} else if(n->rtmetric == rtmetric) {
if(neighbor_etx(n) > etx) {
rtmetric = n->rtmetric;
etx = neighbor_etx(n);
max = n;
/* PRINTF("%d: found worst neighbor %d with rtmetric %d, signal %d\n",
node_id, neighbors[n].nodeid, rtmetric, signal);*/
}
}
}
}
n = max;
}
/* PRINTF("%d: adding neighbor %d with rtmetric %d, signal %d at %d\n",
node_id, neighbors[n].nodeid, rtmetric, signal, n);*/
if(n != NULL) {
n->time = 0;
rimeaddr_copy(&n->addr, addr);
n->rtmetric = nrtmetric;
for(i = 0; i < NEIGHBOR_NUM_ETXS; ++i) {
n->etxs[i] = netx;
}
n->etxptr = 0;
}
}
/*---------------------------------------------------------------------------*/
void
neighbor_remove(const rimeaddr_t *addr)
{
struct neighbor *n;
for(n = list_head(neighbors_list); n != NULL; n = n->next) {
if(rimeaddr_cmp(&n->addr, addr)) {
PRINTF("%d.%d: removing %d.%d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
addr->u8[0], addr->u8[1]);
rimeaddr_copy(&n->addr, &rimeaddr_null);
n->rtmetric = RTMETRIC_MAX;
list_remove(neighbors_list, n);
memb_free(&neighbors_mem, n);
return;
}
}
/* int i;
for(i = 0; i < MAX_NEIGHBORS; ++i) {
if(rimeaddr_cmp(&neighbors[i].addr, addr)) {
PRINTF("%d: removing %d @ %d\n", rimeaddr_node_addr.u16[0], addr->u16[0], i);
rimeaddr_copy(&neighbors[i].addr, &rimeaddr_null);
neighbors[i].rtmetric = RTMETRIC_MAX;
return;
}
}*/
}
/*---------------------------------------------------------------------------*/
struct neighbor *
neighbor_best(void)
{
int found;
/* int lowest, best;*/
struct neighbor *n, *best;
uint16_t rtmetric;
rtmetric = RTMETRIC_MAX;
best = NULL;
found = 0;
/* PRINTF("%d: ", node_id);*/
/* Find the lowest rtmetric. */
for(n = list_head(neighbors_list); n != NULL; n = n->next) {
if(!rimeaddr_cmp(&n->addr, &rimeaddr_null) &&
rtmetric > n->rtmetric + neighbor_etx(n)) {
rtmetric = n->rtmetric + neighbor_etx(n);
best = n;
}
}
return best;
}
/*---------------------------------------------------------------------------*/
void
neighbor_set_lifetime(int seconds)
{
max_time = seconds;
}
/*---------------------------------------------------------------------------*/
int
neighbor_num(void)
{
PRINTF("neighbor_num %d\n", list_length(neighbors_list));
return list_length(neighbors_list);
}
/*---------------------------------------------------------------------------*/
struct neighbor *
neighbor_get(int num)
{
int i;
struct neighbor *n;
PRINTF("neighbor_get %d\n", num);
i = 0;
for(n = list_head(neighbors_list); n != NULL; n = n->next) {
if(i == num) {
PRINTF("neighbor_get found %d.%d\n", n->addr.u8[0], n->addr.u8[1]);
return n;
}
i++;
}
return NULL;
}
/*---------------------------------------------------------------------------*/
/** @} */