osd-contiki/core/net/rime/nf.c
2007-03-15 09:56:30 +00:00

185 lines
5.2 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.
*
* $Id: nf.c,v 1.2 2007/03/15 09:56:30 adamdunkels Exp $
*/
/**
* \file
* Best-effort network flooding (nf)
* \author
* Adam Dunkels <adam@sics.se>
*/
#include "net/rime/nf.h"
#include "net/rime.h"
#include "lib/rand.h"
#include <string.h>
#define QUEUE_TIME ((CLOCK_SECOND / 16) * (rand() % 16))
#define HOPS_MAX 16
struct nf_hdr {
u8_t hops;
u8_t originator_seqno;
node_id_t originator_id;
};
static u8_t seqno;
static void send(void *ptr);
/*---------------------------------------------------------------------------*/
static void
set_timer(struct nf_conn *c)
{
ctimer_set(&c->t, QUEUE_TIME, send, c);
}
/*---------------------------------------------------------------------------*/
static void
send(void *ptr)
{
struct nf_conn *c = ptr;
if(c->packets_received > 0) {
c->packets_received = 0;
set_timer(c);
} else {
/* DEBUGF(3, "nf: send()\n");*/
queuebuf_to_rimebuf(c->buf);
queuebuf_free(c->buf);
c->buf = NULL;
ibc_send(&c->c);
if(c->u->sent != NULL) {
c->u->sent(c);
}
}
}
/*---------------------------------------------------------------------------*/
static int
queue_for_send(struct nf_conn *c)
{
if(c->buf == NULL) {
c->buf = queuebuf_new_from_rimebuf();
}
if(c->buf == NULL) {
return 0;
}
c->packets_received = 0;
set_timer(c);
return 1;
}
/*---------------------------------------------------------------------------*/
static void
recv_from_ibc(struct ibc_conn *ibc, node_id_t from_id)
{
register struct nf_conn *c = (struct nf_conn *)ibc;
struct nf_hdr *hdr = rimebuf_dataptr();
u8_t hops;
struct queuebuf *queuebuf;
c->packets_received++;
hops = hdr->hops;
/* Remember packet if we need to forward it. */
queuebuf = queuebuf_new_from_rimebuf();
rimebuf_hdrreduce(sizeof(struct nf_hdr));
if(c->u->recv != NULL) {
if(!(hdr->originator_id == c->last_originator_id &&
hdr->originator_seqno <= c->last_originator_seqno)) {
if(c->u->recv(c, from_id, hdr->originator_id, hdr->originator_seqno,
hops)) {
if(queuebuf != NULL) {
queuebuf_to_rimebuf(queuebuf);
queuebuf_free(queuebuf);
queuebuf = NULL;
hdr = rimebuf_dataptr();
/* Rebroadcast received packet. */
if(hops < HOPS_MAX) {
/* printf("rebroadcasting %d/%d (%d/%d) hops %d\n",
hdr->originator_id, hdr->originator_seqno,
c->last_originator_id, c->last_originator_seqno,
hops);*/
hdr->hops++;
queue_for_send(c);
c->last_originator_id = hdr->originator_id;
c->last_originator_seqno = hdr->originator_seqno;
}
}
}
}
}
if(queuebuf != NULL) {
queuebuf_free(queuebuf);
}
}
/*---------------------------------------------------------------------------*/
static const struct ibc_ulayer nf = {recv_from_ibc};
/*---------------------------------------------------------------------------*/
void
nf_setup(struct nf_conn *c, u16_t channel,
const struct nf_ulayer *u)
{
ibc_setup(&c->c, channel, &nf);
c->u = u;
}
/*---------------------------------------------------------------------------*/
int
nf_send(struct nf_conn *c)
{
if(c->buf != NULL) {
queuebuf_free(c->buf);
c->buf = NULL;
}
if(rimebuf_hdrextend(sizeof(struct nf_hdr))) {
struct nf_hdr *hdr = rimebuf_hdrptr();
c->last_originator_id = hdr->originator_id = node_id;
c->last_originator_seqno = hdr->originator_seqno = ++seqno;
hdr->hops = 0;
return queue_for_send(c);
}
return 0;
}
/*---------------------------------------------------------------------------*/
void
nf_cancel(struct nf_conn *c)
{
ctimer_stop(&c->t);
}
/*---------------------------------------------------------------------------*/