paho.mqtt-sn.embedded-c/MQTTSNPacket/samples/linux/rfcomm/pub0sub1.c

/*******************************************************************************
 * Copyright (c) 2014 IBM Corp.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * and Eclipse Distribution License v1.0 which accompany this distribution.
 *
 * The Eclipse Public License is available at
 *    http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 *   http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *    Ian Craggs - initial API and implementation and/or initial documentation
 *    Sergio R. Caprile - clarifications and/or documentation extension
 *
 * Description:
 * Normal topic name is automatically registered at subscription, then
 * a message is published and the node receives it itself
 *******************************************************************************/

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "MQTTSNPacket.h"
#include "rfcomm.h"


int main(int argc, char** argv)
{
	int rc = 0;
	unsigned char buf[200];
	int buflen = sizeof(buf);
	MQTTSN_topicid topic;
	unsigned char* payload = (unsigned char*)"mypayload";
	int payloadlen = strlen((char*)payload);
	int len = 0;
	unsigned char dup = 0;
	int qos = 1;
	unsigned char retained = 0;
	short packetid = 1;
	char *topicname = "a long topic name";
    char *host = "";
    int channel = 1;
	MQTTSNPacket_connectData options = MQTTSNPacket_connectData_initializer;
	unsigned short topicid;

	if (argc > 1)
		host = argv[1];

	if (argc > 2)
        channel = atoi(argv[2]);

    printf("Sending to address %s channel %d\n", host, channel);
    if (rfcomm_open(host, channel) < 0)
    {
        goto exit;
    }

	options.clientID.cstring = "pub0sub1 MQTT-SN";
	len = MQTTSNSerialize_connect(buf, buflen, &options);
    rc = rfcomm_sendPacketBuffer(buf, len);

	/* wait for connack */
    if (MQTTSNPacket_read(buf, buflen, rfcomm_getdata) == MQTTSN_CONNACK)
	{
		int connack_rc = -1;

		if (MQTTSNDeserialize_connack(&connack_rc, buf, buflen) != 1 || connack_rc != 0)
		{
			printf("Unable to connect, return code %d\n", connack_rc);
			goto exit;
		}
		else 
			printf("connected rc %d\n", connack_rc);
	}
	else
		goto exit;


	/* subscribe */
	printf("Subscribing\n");
	topic.type = MQTTSN_TOPIC_TYPE_NORMAL;
	topic.data.long_.name = topicname;
	topic.data.long_.len = strlen(topic.data.long_.name);
	len = MQTTSNSerialize_subscribe(buf, buflen, 0, 2, packetid, &topic);
    rc = rfcomm_sendPacketBuffer(buf, len);

    if (MQTTSNPacket_read(buf, buflen, rfcomm_getdata) == MQTTSN_SUBACK) /* wait for suback */
	{
		unsigned short submsgid;
		int granted_qos;
		unsigned char returncode;

		rc = MQTTSNDeserialize_suback(&granted_qos, &topicid, &submsgid, &returncode, buf, buflen);
		if (granted_qos != 2 || returncode != 0)
		{
			printf("granted qos != 2, %d return code %d\n", granted_qos, returncode);
			goto exit;
		}
		else
			printf("suback topic id %d\n", topicid);
	}
	else
		goto exit;

	printf("Publishing\n");
	/* publish with short name */
	topic.type = MQTTSN_TOPIC_TYPE_NORMAL;
	topic.data.id = topicid;
	++packetid;
	len = MQTTSNSerialize_publish(buf, buflen, dup, qos, retained, packetid,
			topic, payload, payloadlen);
    rc = rfcomm_sendPacketBuffer(buf, len);

	/* wait for puback */
    if (MQTTSNPacket_read(buf, buflen, rfcomm_getdata) == MQTTSN_PUBACK)
	{
		unsigned short packet_id, topic_id;
		unsigned char returncode;

		if (MQTTSNDeserialize_puback(&topic_id, &packet_id, &returncode, buf, buflen) != 1 || returncode != MQTTSN_RC_ACCEPTED)
			printf("Unable to publish, return code %d\n", returncode);
		else 
			printf("puback received, msgid %d topic id %d\n", packet_id, topic_id);
	}
	else
		goto exit;

	printf("Receive publish\n");
    if (MQTTSNPacket_read(buf, buflen, rfcomm_getdata) == MQTTSN_PUBLISH)
	{
		unsigned short packet_id;
		int qos, payloadlen;
		unsigned char* payload;
		unsigned char dup, retained;
		MQTTSN_topicid pubtopic;

		if (MQTTSNDeserialize_publish(&dup, &qos, &retained, &packet_id, &pubtopic,
				&payload, &payloadlen, buf, buflen) != 1)
			printf("Error deserializing publish\n");
		else 
			printf("publish received, id %d qos %d\n", packet_id, qos);

		if (qos == 1)
		{
			len = MQTTSNSerialize_puback(buf, buflen, pubtopic.data.id, packet_id, MQTTSN_RC_ACCEPTED);
            rc = rfcomm_sendPacketBuffer(buf, len);
			if (rc == 0)
				printf("puback sent\n");
		}
	}
	else
		goto exit;

	len = MQTTSNSerialize_disconnect(buf, buflen, 0);
    rc = rfcomm_sendPacketBuffer(buf, len);

exit:
	rfcomm_close();

	return 0;
}