contiki/apps/er-coap-07/er-coap-07-transactions.c
2012-01-31 04:38:07 +01:00

196 lines
6.2 KiB
C

/*
* Copyright (c) 2011, Institute for Pervasive Computing, ETH Zurich
* 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
* CoAP module for reliable transport
* \author
* Matthias Kovatsch <kovatsch@inf.ethz.ch>
*/
#include "contiki.h"
#include "contiki-net.h"
#include "er-coap-07-transactions.h"
#include "er-coap-07-observing.h"
/*
* Modulo mask (+1 and +0.5 for rounding) for a random number to get the tick number for the random
* retransmission time between COAP_RESPONSE_TIMEOUT and COAP_RESPONSE_TIMEOUT*COAP_RESPONSE_RANDOM_FACTOR.
*/
#define COAP_RESPONSE_TIMEOUT_TICKS (CLOCK_SECOND * COAP_RESPONSE_TIMEOUT)
#define COAP_RESPONSE_TIMEOUT_BACKOFF_MASK ((CLOCK_SECOND * COAP_RESPONSE_TIMEOUT * (COAP_RESPONSE_RANDOM_FACTOR - 1)) + 1.5)
#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#define PRINT6ADDR(addr) PRINTF("[%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x]", ((uint8_t *)addr)[0], ((uint8_t *)addr)[1], ((uint8_t *)addr)[2], ((uint8_t *)addr)[3], ((uint8_t *)addr)[4], ((uint8_t *)addr)[5], ((uint8_t *)addr)[6], ((uint8_t *)addr)[7], ((uint8_t *)addr)[8], ((uint8_t *)addr)[9], ((uint8_t *)addr)[10], ((uint8_t *)addr)[11], ((uint8_t *)addr)[12], ((uint8_t *)addr)[13], ((uint8_t *)addr)[14], ((uint8_t *)addr)[15])
#define PRINTLLADDR(lladdr) PRINTF("[%02x:%02x:%02x:%02x:%02x:%02x]",(lladdr)->addr[0], (lladdr)->addr[1], (lladdr)->addr[2], (lladdr)->addr[3],(lladdr)->addr[4], (lladdr)->addr[5])
#else
#define PRINTF(...)
#define PRINT6ADDR(addr)
#define PRINTLLADDR(addr)
#endif
MEMB(transactions_memb, coap_transaction_t, COAP_MAX_OPEN_TRANSACTIONS);
LIST(transactions_list);
static struct process *transaction_handler_process = NULL;
void
coap_register_as_transaction_handler()
{
transaction_handler_process = PROCESS_CURRENT();
}
coap_transaction_t *
coap_new_transaction(uint16_t mid, uip_ipaddr_t *addr, uint16_t port)
{
coap_transaction_t *t = memb_alloc(&transactions_memb);
if (t)
{
t->mid = mid;
t->retrans_counter = 0;
/* save client address */
uip_ipaddr_copy(&t->addr, addr);
t->port = port;
list_add(transactions_list, t); /* List itself makes sure same element is not added twice. */
}
return t;
}
void
coap_send_transaction(coap_transaction_t *t)
{
PRINTF("Sending transaction %u\n", t->mid);
coap_send_message(&t->addr, t->port, t->packet, t->packet_len);
if (COAP_TYPE_CON==((COAP_HEADER_TYPE_MASK & t->packet[0])>>COAP_HEADER_TYPE_POSITION))
{
if (t->retrans_counter<COAP_MAX_RETRANSMIT)
{
PRINTF("Keeping transaction %u\n", t->mid);
if (t->retrans_counter==0)
{
t->retrans_timer.timer.interval = COAP_RESPONSE_TIMEOUT_TICKS + (random_rand() % (clock_time_t) COAP_RESPONSE_TIMEOUT_BACKOFF_MASK);
PRINTF("Initial interval %f\n", (float)t->retrans_timer.timer.interval/CLOCK_SECOND);
}
else
{
t->retrans_timer.timer.interval <<= 1; /* double */
PRINTF("Doubled (%u) interval %f\n", t->retrans_counter, (float)t->retrans_timer.timer.interval/CLOCK_SECOND);
}
/*FIXME hack, maybe there is a better way, but avoid posting everything to the process */
struct process *process_actual = PROCESS_CURRENT();
process_current = transaction_handler_process;
etimer_restart(&t->retrans_timer); /* interval updated above */
process_current = process_actual;
t = NULL;
}
else
{
/* timeout */
PRINTF("Timeout\n");
restful_response_handler callback = t->callback;
void *callback_data = t->callback_data;
/* handle observers */
coap_remove_observer_by_client(&t->addr, t->port);
coap_clear_transaction(t);
if (callback) {
callback(callback_data, NULL);
}
}
}
else
{
coap_clear_transaction(t);
}
}
void
coap_clear_transaction(coap_transaction_t *t)
{
if (t)
{
PRINTF("Freeing transaction %u: %p\n", t->mid, t);
etimer_stop(&t->retrans_timer);
list_remove(transactions_list, t);
memb_free(&transactions_memb, t);
}
}
coap_transaction_t *
coap_get_transaction_by_mid(uint16_t mid)
{
coap_transaction_t *t = NULL;
for (t = (coap_transaction_t*)list_head(transactions_list); t; t = t->next)
{
if (t->mid==mid)
{
PRINTF("Found transaction for MID %u: %p\n", t->mid, t);
return t;
}
}
return NULL;
}
void
coap_check_transactions()
{
coap_transaction_t *t = NULL;
for (t = (coap_transaction_t*)list_head(transactions_list); t; t = t->next)
{
if (etimer_expired(&t->retrans_timer))
{
++(t->retrans_counter);
PRINTF("Retransmitting %u (%u)\n", t->mid, t->retrans_counter);
coap_send_transaction(t);
}
}
}