contiki/core/net/rime/trickle.c

155 lines
4.6 KiB
C

/**
* \addtogroup trickle
* @{
*/
/*
* Copyright (c) 2007, 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: trickle.c,v 1.6 2008/01/08 07:59:51 adamdunkels Exp $
*/
/**
* \file
* Trickle (reliable single source flooding) for Rime
* \author
* Adam Dunkels <adam@sics.se>
*/
#include "net/rime/trickle.h"
#define INTERVAL_MIN 1
#define INTERVAL_MAX 4
#define SEQNO_LT(a, b) ((signed char)((a) - (b)) < 0)
#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif
/*---------------------------------------------------------------------------*/
static void
send(void *ptr)
{
struct trickle_conn *c = ptr;
if(c->q != NULL) {
queuebuf_to_rimebuf(c->q);
nf_send(&c->c, c->seqno);
ctimer_set(&c->t, c->interval << c->interval_scaling,
send, c);
} else {
PRINTF("%d.%d: trickle send but c->q == NULL\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1]);
}
}
/*---------------------------------------------------------------------------*/
static int
recv(struct nf_conn *nf, rimeaddr_t *from,
rimeaddr_t *originator, u8_t seqno, u8_t hops)
{
struct trickle_conn *c = (struct trickle_conn *)nf;
PRINTF("%d.%d: trickle recv seqno %d our %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
seqno, c->seqno);
if(seqno == c->seqno) {
/* c->cb->recv(c);*/
} else if(SEQNO_LT(seqno, c->seqno)) {
c->interval_scaling = 0;
send(c);
} else { /* hdr->seqno > c->seqno */
c->seqno = seqno;
/* Store the incoming data in the queuebuf */
if(c->q != NULL) {
queuebuf_free(c->q);
}
c->q = queuebuf_new_from_rimebuf();
c->interval_scaling = 0;
send(c);
c->cb->recv(c);
}
return 0;
}
/*---------------------------------------------------------------------------*/
static void
sent_or_dropped(struct nf_conn *nf)
{
struct trickle_conn *c = (struct trickle_conn *)nf;
c->interval_scaling++;
if(c->interval_scaling > INTERVAL_MAX) {
c->interval_scaling = INTERVAL_MAX;
}
}
/*---------------------------------------------------------------------------*/
static const struct nf_callbacks nf = {recv,
sent_or_dropped,
sent_or_dropped};
/*---------------------------------------------------------------------------*/
void
trickle_open(struct trickle_conn *c, clock_time_t interval,
u16_t channel, const struct trickle_callbacks *cb)
{
nf_open(&c->c, interval, channel, &nf);
c->cb = cb;
c->q = NULL;
c->interval = interval;
}
/*---------------------------------------------------------------------------*/
void
trickle_close(struct trickle_conn *c)
{
nf_close(&c->c);
ctimer_stop(&c->t);
}
/*---------------------------------------------------------------------------*/
void
trickle_send(struct trickle_conn *c)
{
if(c->q != NULL) {
queuebuf_free(c->q);
}
c->q = queuebuf_new_from_rimebuf();
c->seqno++;
PRINTF("%d.%d: trickle send seqno %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
c->seqno);
send(c);
}
/*---------------------------------------------------------------------------*/
/** @} */