/* * mqtt subscribe * * @build make examples * @sub bin/mqtt_sub 127.0.0.1 1883 topic * @pub bin/mqtt_pub 127.0.0.1 1883 topic payload * */ #include "hv.h" #include "mqtt_client.h" /* * @test MQTTS * #define TEST_SSL 1 * * @build ./configure --with-mqtt --with-openssl && make clean && make * */ #define TEST_SSL 0 #define TEST_AUTH 0 #define TEST_RECONNECT 1 /* * workflow: * mqtt_client_new -> mqtt_client_xxx -> mqtt_client_run * * mqtt_client_set_xxx -> * mqtt_client_connect -> * on_connack -> mqtt_client_subscribe -> * on_publish -> handle_message * */ static void handle_message(mqtt_client_t* cli, mqtt_message_t* msg) { printf("topic: %.*s\n", msg->topic_len, msg->topic); printf("payload: %.*s\n", msg->payload_len, msg->payload); } static void on_mqtt(mqtt_client_t* cli, int type) { printf("on_mqtt type=%d\n", type); switch(type) { case MQTT_TYPE_CONNECT: printf("mqtt connected!\n"); if (cli->reconn_setting && cli->reconn_setting->cur_retry_cnt > 0) { printf("mqtt reconnect cnt=%d, delay=%d\n", cli->reconn_setting->cur_retry_cnt, cli->reconn_setting->cur_delay); } break; case MQTT_TYPE_DISCONNECT: printf("mqtt disconnected!\n"); if (cli->reconn_setting && cli->reconn_setting->cur_retry_cnt > 0) { printf("mqtt reconnect cnt=%d, delay=%d\n", cli->reconn_setting->cur_retry_cnt, cli->reconn_setting->cur_delay); } break; case MQTT_TYPE_CONNACK: printf("mqtt connack!\n"); { const char* topic = (const char*)mqtt_client_get_userdata(cli); int mid = mqtt_client_subscribe(cli, topic, 0); printf("mqtt subscribe mid=%d\n", mid); } break; case MQTT_TYPE_SUBACK: printf("mqtt suback mid=%d\n", cli->mid); break; case MQTT_TYPE_PUBLISH: handle_message(cli, &cli->message); default: break; } } static int mqtt_subscribe(const char* host, int port, const char* topic) { mqtt_client_t* cli = mqtt_client_new(NULL); if (cli == NULL) return -1; cli->keepalive = 10; #if TEST_AUTH mqtt_client_set_auth(cli, "test", "123456"); #endif mqtt_client_set_userdata(cli, (void*)topic); mqtt_client_set_callback(cli, on_mqtt); #if TEST_RECONNECT reconn_setting_t reconn; reconn_setting_init(&reconn); reconn.min_delay = 1000; reconn.max_delay = 10000; reconn.delay_policy = 2; mqtt_client_set_reconnect(cli, &reconn); #endif int ssl = 0; #if TEST_SSL ssl = 1; #endif mqtt_client_connect(cli, host, port, ssl); mqtt_client_run(cli); mqtt_client_free(cli); return 0; } int main(int argc, char** argv) { if (argc < 4) { printf("Usage: %s host port topic\n", argv[0]); return -10; } const char* host = argv[1]; int port = atoi(argv[2]); const char* topic = argv[3]; return mqtt_subscribe(host, port, topic); }