thermometers/main.c

/*****************************************************************************
 * Copyright (C) 2014
 *   
 * Michiel Broek <mbroek at mbse dot eu>
 *
 * This file is part of the mbsePi-apps
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2, or (at your option) any
 * later version.
 *
 * mbsePi-apps is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with EC-65K; see the file COPYING.  If not, write to the Free
 * Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *****************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <getopt.h>
#include <sys/types.h>
#include <signal.h>
#include <string.h>
#include <errno.h>

#include <mosquitto.h>


#include "main.h"


#define STATUS_CONNECTING 0
#define STATUS_CONNACK_RECVD 1
#define STATUS_WAITING 2

/* Global variables for use in callbacks. See sub_client.c for an example of
 * using a struct to hold variables for use in callbacks. */
static char *topic = NULL;
//static char *message = NULL;
//static long msglen = 0;
static int qos = 0;
//static int retain = 0;
static int status = STATUS_CONNECTING;
static int mid_sent = 0;
static int last_mid = -1;
static int last_mid_sent = -1;
static bool connected = true;
//static char *username = NULL;
//static char *password = NULL;
static bool disconnect_sent = false;
static bool quiet = false;
static bool debug = false;
static bool shutdown = false;


void help(void)
{
    fprintf(stdout, "Usage: thermomeneters [-d] [-h]\n");
    fprintf(stdout, "  -d --debug              Debug on\n");
    fprintf(stdout, "  -h --help               Display this help\n");
}


void die(int onsig)
{
    switch (onsig) {
	case SIGHUP:	fprintf(stdout, "[main] Hangup detected\n");
			break;
	case SIGINT:	fprintf(stdout, "[main] Interrupt from keyboard\n");
			break;
	case SIGTERM:	fprintf(stdout, "[main] Termination signal received\n");
			break;
	default:	fprintf(stdout, "[main] die on signal %d\n", onsig);
    }

    shutdown = true;
}


void my_connect_callback(struct mosquitto *mosq, void *obj, int result)
{
    int rc = MOSQ_ERR_SUCCESS;

    fprintf(stdout, (char *)"my_connect_callback result=%d\n", result);
    if (!result) {
	status = STATUS_CONNACK_RECVD;
    } else {
	fprintf(stderr, "%s\n", mosquitto_connack_string(result));
    }
}


void my_disconnect_callback(struct mosquitto *mosq, void *obj, int rc)
{
    fprintf(stdout, (char *)"my_disconnect_callback\n");
    connected = false;
}


void my_publish_callback(struct mosquitto *mosq, void *obj, int mid)
{
    fprintf(stdout, (char *)"my_publish_callback mid=%d\n", mid);

    last_mid_sent = mid;
}


void my_log_callback(struct mosquitto *mosq, void *obj, int level, const char *str)
{
        printf("log: %s\n", str);
}


int main(int argc, char *argv[])
{
    int			i, c, len, rc, rc2;
    char		*id = NULL;
    char		*host = (char *)"lx02.mbse.ym";
    int			port = 1883;
    struct mosquitto	*mosq = NULL;
    char		hostname[256], buf[1024];
    int			keepalive = 60;
    unsigned int	max_inflight = 20;
    char		err[1024];

    while (1) {
	int option_index = 0;
	static struct option long_options[] = {
	    {"debug", 0, 0, 'c'},
	    {"help", 0, 0, 'h'},
	    {0, 0, 0, 0}
	};

	c = getopt_long(argc, argv, "dh", long_options, &option_index);
	if (c == -1)
	    break;

	switch (c) {
	    case 'd':	debug = true;
			break;
	    case 'h':	help();
			return 1;
	}
    }

    /*
     *  Catch all the signals we can, and ignore the rest. Note that SIGKILL can't be ignored
     *  but that's live. This daemon should only be stopped by SIGTERM.
     *  Don't catch SIGCHLD.
     */
    for (i = 0; i < NSIG; i++) {
    	if ((i != SIGCHLD) && (i != SIGKILL) && (i != SIGSTOP))
	    signal(i, (void (*))die);
    }

    /*
     * Initialize mosquitto communication
     */
    mosquitto_lib_init();
    hostname[0] = '\0';
    gethostname(hostname, 256);
    hostname[255] = '\0';
    len = strlen("thermometers/") + 1 + strlen(hostname);
    id = malloc(len);
    if(!id) {
	if (!quiet)
	    fprintf(stderr, "Error: Out of memory.\n");
	mosquitto_lib_cleanup();
	return 1;
    }
    snprintf(id, len, "thermometers/%s", hostname);
    if(strlen(id) > MOSQ_MQTT_ID_MAX_LENGTH) {
	/*
	 * Enforce maximum client id length of 23 characters
	 */
	id[MOSQ_MQTT_ID_MAX_LENGTH] = '\0';
    }

    fprintf(stdout, "id: %s\n", id);

    mosq = mosquitto_new(id, true, NULL);
    if(!mosq) {
	switch(errno) {
	    case ENOMEM:
		if (!quiet)
		    fprintf(stderr, "Error: Out of memory.\n");
		break;
	    case EINVAL:
		if (!quiet)
		    fprintf(stderr, "Error: Invalid id.\n");
		break;
	}
	mosquitto_lib_cleanup();
	return 1;
    }

    if(debug) {
	mosquitto_log_callback_set(mosq, my_log_callback);
    }

    /*
     * Set our will
     */
    topic = malloc(28 + strlen(hostname));
    sprintf(topic, "clients/%s/thermometers/state", hostname);
    sprintf(buf, "0");
    rc = mosquitto_will_set(mosq, topic, strlen(buf), buf, qos, true);
    if (rc) {
        if (rc == MOSQ_ERR_INVAL) {
            fprintf(stderr, "Input parameters invalid\n");
        } else if (rc == MOSQ_ERR_NOMEM) {
            fprintf(stderr, "Out of Memory\n");
	} else if (rc == MOSQ_ERR_PAYLOAD_SIZE) {
	    fprintf(stderr, "Invalid payload size\n");
        }
        mosquitto_lib_cleanup();
        return rc;
    }

    mosquitto_max_inflight_messages_set(mosq, max_inflight);
    mosquitto_connect_callback_set(mosq, my_connect_callback);
    mosquitto_disconnect_callback_set(mosq, my_disconnect_callback);
    mosquitto_publish_callback_set(mosq, my_publish_callback);

    rc = mosquitto_connect(mosq, host, port, keepalive);
    if (rc) {
	if (rc == MOSQ_ERR_ERRNO) {
	    strerror_r(errno, err, 1024);
	    fprintf(stderr, "Error: %s\n", err);
	} else {
	    fprintf(stderr, "Unable to connect (%d).\n", rc);
	}
	mosquitto_lib_cleanup();
	return rc;
    }

    /*
     * Initialise is complete, report our presence state
     */
    mosquitto_loop_start(mosq);

//    topic = malloc(28 + strlen(hostname));
    sprintf(topic, "clients/%s/thermometers/state", hostname);
    sprintf(buf, "1");
    rc2 = mosquitto_publish(mosq, &mid_sent, topic, strlen(buf), buf, qos, 1);
    free(topic);


    fprintf(stdout, (char *)"Enter loop, connected %d\n", connected);
    do {
	if (status == STATUS_CONNACK_RECVD) {
//	    fprintf(stdout, (char *)"Ok\n");
//                                if(fgets(buf, 1024, stdin)){
//                                        buf[strlen(buf)-1] = '\0';
//                                        rc2 = mosquitto_publish(mosq, &mid_sent, topic, strlen(buf), buf, qos, retain);
//                                        if(rc2){
//                                                if(!quiet) fprintf(stderr, "Error: Publish returned %d, disconnecting.\n", rc2);
//                                                mosquitto_disconnect(mosq);
//                                        }
//	    } else
	    if (shutdown) {
		fprintf(stdout, (char *)"Shutdown\n");
		topic = malloc(28 + strlen(hostname));
		sprintf(topic, "clients/%s/thermometers/state", hostname);
		sprintf(buf, "0");
		rc2 = mosquitto_publish(mosq, &mid_sent, topic, strlen(buf), buf, qos, true);
		free(topic);
		last_mid = mid_sent;
		status = STATUS_WAITING;
	    }
	} else if (status == STATUS_WAITING) {
	    fprintf(stdout, (char *)"Waiting\n");
	    if (last_mid_sent == last_mid && disconnect_sent == false) {
		mosquitto_disconnect(mosq);
		disconnect_sent = true;
	    }
	    usleep(100000);
	}
	rc = MOSQ_ERR_SUCCESS;

    } while(rc == MOSQ_ERR_SUCCESS && connected);
    fprintf(stdout, (char *)"Out of loop\n");

    mosquitto_loop_stop(mosq, false);

    mosquitto_destroy(mosq);
    mosquitto_lib_cleanup();

    fprintf(stdout, (char *)"Bye Bye\n");
    return 0;
}