| /******************************************************************************* |
| * Copyright (c) 2012, 2020 IBM Corp. |
| * |
| * All rights reserved. This program and the accompanying materials |
| * are made available under the terms of the Eclipse Public License v2.0 |
| * and Eclipse Distribution License v1.0 which accompany this distribution. |
| * |
| * The Eclipse Public License is available at |
| * https://www.eclipse.org/legal/epl-2.0/ |
| * and the Eclipse Distribution License is available at |
| * http://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * Contributors: |
| * Ian Craggs - initial contribution |
| *******************************************************************************/ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include "MQTTClient.h" |
| |
| #define ADDRESS "tcp://mqtt.eclipse.org:1883" |
| #define CLIENTID "ExampleClientSub" |
| #define TOPIC "MQTT Examples" |
| #define PAYLOAD "Hello World!" |
| #define QOS 1 |
| #define TIMEOUT 10000L |
| |
| volatile MQTTClient_deliveryToken deliveredtoken; |
| |
| void delivered(void *context, MQTTClient_deliveryToken dt) |
| { |
| printf("Message with token value %d delivery confirmed\n", dt); |
| deliveredtoken = dt; |
| } |
| |
| int msgarrvd(void *context, char *topicName, int topicLen, MQTTClient_message *message) |
| { |
| printf("Message arrived\n"); |
| printf(" topic: %s\n", topicName); |
| printf(" message: %.*s\n", message->payloadlen, (char*)message->payload); |
| MQTTClient_freeMessage(&message); |
| MQTTClient_free(topicName); |
| return 1; |
| } |
| |
| void connlost(void *context, char *cause) |
| { |
| printf("\nConnection lost\n"); |
| printf(" cause: %s\n", cause); |
| } |
| |
| int main(int argc, char* argv[]) |
| { |
| MQTTClient client; |
| MQTTClient_connectOptions conn_opts = MQTTClient_connectOptions_initializer; |
| int rc; |
| |
| if ((rc = MQTTClient_create(&client, ADDRESS, CLIENTID, |
| MQTTCLIENT_PERSISTENCE_NONE, NULL)) != MQTTCLIENT_SUCCESS) |
| { |
| printf("Failed to create client, return code %d\n", rc); |
| rc = EXIT_FAILURE; |
| goto exit; |
| } |
| |
| if ((rc = MQTTClient_setCallbacks(client, NULL, connlost, msgarrvd, delivered)) != MQTTCLIENT_SUCCESS) |
| { |
| printf("Failed to set callbacks, return code %d\n", rc); |
| rc = EXIT_FAILURE; |
| goto destroy_exit; |
| } |
| |
| conn_opts.keepAliveInterval = 20; |
| conn_opts.cleansession = 1; |
| if ((rc = MQTTClient_connect(client, &conn_opts)) != MQTTCLIENT_SUCCESS) |
| { |
| printf("Failed to connect, return code %d\n", rc); |
| rc = EXIT_FAILURE; |
| goto destroy_exit; |
| } |
| |
| printf("Subscribing to topic %s\nfor client %s using QoS%d\n\n" |
| "Press Q<Enter> to quit\n\n", TOPIC, CLIENTID, QOS); |
| if ((rc = MQTTClient_subscribe(client, TOPIC, QOS)) != MQTTCLIENT_SUCCESS) |
| { |
| printf("Failed to subscribe, return code %d\n", rc); |
| rc = EXIT_FAILURE; |
| } |
| else |
| { |
| int ch; |
| do |
| { |
| ch = getchar(); |
| } while (ch!='Q' && ch != 'q'); |
| |
| if ((rc = MQTTClient_unsubscribe(client, TOPIC)) != MQTTCLIENT_SUCCESS) |
| { |
| printf("Failed to unsubscribe, return code %d\n", rc); |
| rc = EXIT_FAILURE; |
| } |
| } |
| |
| if ((rc = MQTTClient_disconnect(client, 10000)) != MQTTCLIENT_SUCCESS) |
| { |
| printf("Failed to disconnect, return code %d\n", rc); |
| rc = EXIT_FAILURE; |
| } |
| destroy_exit: |
| MQTTClient_destroy(&client); |
| exit: |
| return rc; |
| } |