contiki/core/net/rime/polite.c
2014-01-26 23:20:45 +01:00

153 lines
4.4 KiB
C

/**
* \addtogroup rimepolite
* @{
*/
/*
* 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.
*
*/
/**
* \file
* Polite Anonymous best effort local area BroadCast (polite)
* \author
* Adam Dunkels <adam@sics.se>
*/
#include "net/rime/rime.h"
#include "net/rime/polite.h"
#include "lib/random.h"
#include <string.h>
#ifndef MAX
#define MAX(a,b) ((a) > (b)? (a) : (b))
#endif /* MAX */
#ifndef MIN
#define MIN(a, b) ((a) < (b)? (a) : (b))
#endif /* MIN */
/*---------------------------------------------------------------------------*/
static void
recv(struct abc_conn *abc)
{
struct polite_conn *c = (struct polite_conn *)abc;
if(c->q != NULL &&
packetbuf_datalen() == queuebuf_datalen(c->q) &&
memcmp(packetbuf_dataptr(), queuebuf_dataptr(c->q),
MIN(c->hdrsize, packetbuf_datalen())) == 0) {
/* We received a copy of our own packet, so we do not send out
packet. */
queuebuf_free(c->q);
c->q = NULL;
ctimer_stop(&c->t);
if(c->cb->dropped) {
c->cb->dropped(c);
}
}
if(c->cb->recv) {
c->cb->recv(c);
}
}
/*---------------------------------------------------------------------------*/
static void
sent(struct abc_conn *c, int status, int num_tx)
{
}
/*---------------------------------------------------------------------------*/
static void
send(void *ptr)
{
struct polite_conn *c = ptr;
if(c->q != NULL) {
queuebuf_to_packetbuf(c->q);
queuebuf_free(c->q);
c->q = NULL;
abc_send(&c->c);
if(c->cb->sent) {
c->cb->sent(c);
}
}
}
/*---------------------------------------------------------------------------*/
static const struct abc_callbacks abc = { recv, sent };
/*---------------------------------------------------------------------------*/
void
polite_open(struct polite_conn *c, uint16_t channel,
const struct polite_callbacks *cb)
{
abc_open(&c->c, channel, &abc);
c->cb = cb;
}
/*---------------------------------------------------------------------------*/
void
polite_close(struct polite_conn *c)
{
abc_close(&c->c);
ctimer_stop(&c->t);
if(c->q != NULL) {
queuebuf_free(c->q);
c->q = NULL;
}
}
/*---------------------------------------------------------------------------*/
int
polite_send(struct polite_conn *c, clock_time_t interval, uint8_t hdrsize)
{
if(c->q != NULL) {
/* If we are already about to send a packet, we cancel the old one. */
queuebuf_free(c->q);
}
c->hdrsize = hdrsize;
c->q = queuebuf_new_from_packetbuf();
if(c->q != NULL) {
ctimer_set(&c->t, interval / 2 + (random_rand() % (interval / 2)), send, c);
return 1;
}
return 0;
}
/*---------------------------------------------------------------------------*/
void
polite_cancel(struct polite_conn *c)
{
ctimer_stop(&c->t);
if(c->q != NULL) {
queuebuf_free(c->q);
c->q = NULL;
}
}
/*---------------------------------------------------------------------------*/
/** @} */