/* * 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 */ #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 #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_countermid); 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: Setting timer for responsible process. * 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 { /* Timed out. */ 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); } } }