coolers/mosquitto.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 "../lib/mbselib.h"
#include "coolers.h"

#ifdef HAVE_WIRINGPI_H


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

/* Global variables for use in callbacks. */
struct mosquitto    	*mymosq = NULL;
char			*myhostname;
static int		qos = 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 bool		disconnect_sent = false;
static bool		connect_lost = false;

extern bool		shutdown;
extern bool		debug;
extern sys_config	Config;
extern int		lcdHandle;
extern int		lcdupdate;


void my_connect_callback(struct mosquitto *mosq, void *obj, int result)
{
    if (connect_lost) {
	connect_lost = false;
	syslog(LOG_NOTICE, "Reconnect: %s", mosquitto_connack_string(result));
    }

    if (!result) {
	status = STATUS_CONNACK_RECVD;
    } else {
	syslog(LOG_NOTICE, "my_connect_callback: %s\n", mosquitto_connack_string(result));
    }
}


void my_disconnect_callback(struct mosquitto *mosq, void *obj, int rc)
{
    if (shutdown) {
	syslog(LOG_NOTICE, "Acknowledged DISCONNECT from %s", Config.mosq_host);
	connected = false;
    } else {
	/*
	 * The remove server was brought down. We must keep running
	 */
	syslog(LOG_NOTICE, "Received DISCONNECT from %s, connection lost", Config.mosq_host);
	connect_lost = true;
    }
}


void my_publish_callback(struct mosquitto *mosq, void *obj, int mid)
{
    last_mid_sent = mid;
}


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


int my_mosquitto_init(void)
{
    char                *id = NULL, *state = NULL;
    char                buf[1024];
    int                 rc, keepalive = 60;
    unsigned int        max_inflight = 20;
    char                err[1024];
    w1_therm		*tmp1, *old1;
    rc_switch		*tmp2, *old2;
    char		*alias;

    /*
     * Initialize mosquitto communication
     */
    mosquitto_lib_init();

    gethostname(buf, 255);
    myhostname = xstrcpy(buf);

    /*
     * Build MQTT id
     */
    id = xstrcpy((char *)"coolers/");
    id = xstrcat(id, myhostname);
    if(strlen(id) > MOSQ_MQTT_ID_MAX_LENGTH) {
	/*
	 * Enforce maximum client id length of 23 characters
	 */
	id[MOSQ_MQTT_ID_MAX_LENGTH] = '\0';
    }

    mymosq = mosquitto_new(id, true, NULL);
    if(!mymosq) {
	switch(errno) {
	    case ENOMEM:
		syslog(LOG_NOTICE, "mosquitto_new: Out of memory");
		break;
	    case EINVAL:
		syslog(LOG_NOTICE, "mosquitto_new: Invalid id");
		break;
	}
	mosquitto_lib_cleanup();
	return 1;
    }

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

    /*
     * Set our will
     */
    state = xstrcpy((char *)"clients/");
    state = xstrcat(state, myhostname);
    state = xstrcat(state, (char *)"/coolers/state");
    sprintf(buf, "0");
    if ((rc = mosquitto_will_set(mymosq, state, strlen(buf), buf, qos, true))) {
        if (rc == MOSQ_ERR_INVAL) {
            syslog(LOG_NOTICE, "mosquitto_will_set: input parameters invalid");
        } else if (rc == MOSQ_ERR_NOMEM) {
            syslog(LOG_NOTICE, "mosquitto_will_set: Out of Memory");
	} else if (rc == MOSQ_ERR_PAYLOAD_SIZE) {
	    syslog(LOG_NOTICE, "mosquitto_will_set: invalid payload size");
        }
        mosquitto_lib_cleanup();
        return rc;
    }

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

    if ((rc = mosquitto_connect(mymosq, Config.mosq_host, Config.mosq_port, keepalive))) {
	if (rc == MOSQ_ERR_ERRNO) {
	    strerror_r(errno, err, 1024);
	    syslog(LOG_NOTICE, "mosquitto_connect: error: %s", err);
	} else {
	    syslog(LOG_NOTICE, "mosquitto_connect: unable to connect (%d)", rc);
	}
	mosquitto_lib_cleanup();
	return rc;
    }
    syslog(LOG_NOTICE, "Connected with %s:%d", Config.mosq_host, Config.mosq_port);

    /*
     * Initialise is complete, report our presence state
     */
    mosquitto_loop_start(mymosq);
    sprintf(buf, "1");
    rc = mosquitto_publish(mymosq, &mid_sent, state, strlen(buf), buf, qos, 1);

    /*
     * Report alias names
     */
    for (tmp1 = Config.w1therms; tmp1; tmp1 = old1) {
	old1 = tmp1->next;

	alias = xstrcpy((char *)"/raw/");
	alias = xstrcat(alias, myhostname);
	alias = xstrcat(alias, (char *)"/coolers/w1/");
	alias = xstrcat(alias, tmp1->master);
	alias = xstrcat(alias, (char *)"/");
	alias = xstrcat(alias, tmp1->name);
	alias = xstrcat(alias, (char *)"/alias");

	sprintf(buf, "%s", tmp1->alias);
	if ((rc = mosquitto_publish(mymosq, &mid_sent, alias, strlen(buf), buf, qos, 1))) {
	    if (rc == MOSQ_ERR_NO_CONN)
		mosquitto_reconnect(mymosq);
	    else
		syslog(LOG_NOTICE, "mainloop: error %d from mosquitto_publish", rc);
	}

	free(alias);
	alias = NULL;
    }

    for (tmp2 = Config.rcswitch; tmp2; tmp2 = old2) {
	old2 = tmp2->next;

	alias = xstrcpy((char *)"/raw/");
	alias = xstrcat(alias, myhostname);
	alias = xstrcat(alias, (char *)"/coolers/rcswitch/");
	alias = xstrcat(alias, tmp2->address);
	alias = xstrcat(alias, (char *)"/alias");

	sprintf(buf, "%s", tmp2->alias);
	if ((rc = mosquitto_publish(mymosq, &mid_sent, alias, strlen(buf), buf, qos, 1))) {
	    if (rc == MOSQ_ERR_NO_CONN)
		mosquitto_reconnect(mymosq);
	    else
		syslog(LOG_NOTICE, "mainloop: error %d from mosquitto_publish", rc);
	}

	free(alias);
	alias = NULL;
    }

    return 0;
}


int my_mosquitto_loop(void)
{
    w1_therm		*tmp1, *old1;
    char		buf[1024], *alias, *state = NULL;
    int			rc;

	if (status == STATUS_CONNACK_RECVD) {
	    /*
	     * Here send our 1-wire sensors values
	     */
	    for (tmp1 = Config.w1therms; tmp1; tmp1 = old1) {
		old1 = tmp1->next;

		/*
		 * Build path and alias topic
		 */
		alias = xstrcpy((char *)"/raw/");
		alias = xstrcat(alias, myhostname);
		alias = xstrcat(alias, (char *)"/coolers/w1/");
		alias = xstrcat(alias, tmp1->master);
		alias = xstrcat(alias, (char *)"/");
		alias = xstrcat(alias, tmp1->name);
		alias = xstrcat(alias, (char *)"/temperature");

		if (tmp1->update) {
		    /*
		     * Temperature is changed and valid, update and publish this.
		     */
		    sprintf(buf, "%.1f", tmp1->lastval / 1000.0);
		    if ((rc = mosquitto_publish(mymosq, &mid_sent, alias, strlen(buf), buf, qos, 1))) {
			if (rc == MOSQ_ERR_NO_CONN)
			    mosquitto_reconnect(mymosq);
			else
			    syslog(LOG_NOTICE, "mainloop: error %d from mosquitto_publish", rc);
		    }
		    tmp1->update = FALSE;
		    lcdupdate = TRUE;
		} 

		free(alias);
		alias = NULL;
	    }

	    if (shutdown) {
		/*
		 * Final publish 0 to clients/<hostname>/coolers/state
		 */
		sprintf(buf, "0");
		mosquitto_publish(mymosq, &mid_sent, state, strlen(buf), buf, qos, true);
		last_mid = mid_sent;
		status = STATUS_WAITING;
		lcdClear(lcdHandle);
		lcdPosition(lcdHandle, 0, 0);
		lcdPuts(lcdHandle, "Shuting down ...");
	    }

	    usleep(100000);

	} else if (status == STATUS_WAITING) {
	    if (debug)
	    	fprintf(stdout, (char *)"Waiting\n");
	    if (last_mid_sent == last_mid && disconnect_sent == false) {
		mosquitto_disconnect(mymosq);
		disconnect_sent = true;
	    }
	    usleep(100000);
	}
	rc = MOSQ_ERR_SUCCESS;

    return (rc == MOSQ_ERR_SUCCESS && connected);
}


void my_mosquitto_exit(void)
{
    mosquitto_loop_stop(mymosq, false);
    mosquitto_destroy(mymosq);
    mosquitto_lib_cleanup();
}


#endif