paho.mqtt-sn.embedded-c/MQTTSNGateway/src/MQTTGWPacket.h

/*******************************************************************************
 * Copyright (c) 2009, 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
 *    Ian Craggs, Allan Stockdill-Mander - SSL updates
 *    Ian Craggs - MQTT 3.1.1 support
 *    Tomoaki Yamaguchi - modify codes for MATT-SN Gateway
 *******************************************************************************/

#ifndef MQTTGWPACKET_H_
#define MQTTGWPACKET_H_

#include "Network.h"

namespace MQTTSNGW
{

typedef void* (*pf)(unsigned char, char*, size_t);

#define BAD_MQTT_PACKET -4

enum msgTypes
{
	CONNECT = 1, CONNACK, PUBLISH, PUBACK, PUBREC, PUBREL,
	PUBCOMP, SUBSCRIBE, SUBACK, UNSUBSCRIBE, UNSUBACK,
	PINGREQ, PINGRESP, DISCONNECT
};


/**
 * Bitfields for the MQTT header byte.
 */
typedef union
{
	/*unsigned*/ char byte;	/**< the whole byte */
#if defined(REVERSED)
	struct
	{
		unsigned int type : 4;	/**< message type nibble */
		bool dup : 1;			/**< DUP flag bit */
		unsigned int qos : 2;	/**< QoS value, 0, 1 or 2 */
		bool retain : 1;		/**< retained flag bit */
	} bits;
#else
	struct
	{
		bool retain : 1;		/**< retained flag bit */
		unsigned int qos : 2;	/**< QoS value, 0, 1 or 2 */
		bool dup : 1;			/**< DUP flag bit */
		unsigned int type : 4;	/**< message type nibble */
	} bits;
#endif
} Header;


/**
 * Data for a connect packet.
 */

enum MQTT_connackCodes{
	MQTT_CONNECTION_ACCEPTED ,
	MQTT_UNACCEPTABLE_PROTOCOL_VERSION,
	MQTT_IDENTIFIER_REJECTED,
	MQTT_SERVER_UNAVAILABLE,
	MQTT_BAD_USERNAME_OR_PASSWORD,
	MQTT_NOT_AUTHORIZED
};

typedef struct
{
	Header header;	/**< MQTT header byte */
	union
	{
		unsigned char all;	/**< all connect flags */
#if defined(REVERSED)
		struct
		{
			bool username : 1;			/**< 3.1 user name */
			bool password : 1; 			/**< 3.1 password */
			bool willRetain : 1;		/**< will retain setting */
			unsigned int willQoS : 2;	/**< will QoS value */
			bool will : 1;			/**< will flag */
			bool cleanstart : 1;	/**< cleansession flag */
			int : 1;	/**< unused */
		} bits;
#else
		struct
		{
			int : 1;	/**< unused */
			bool cleanstart : 1;	/**< cleansession flag */
			bool will : 1;			/**< will flag */
			unsigned int willQoS : 2;	/**< will QoS value */
			bool willRetain : 1;		/**< will retain setting */
			bool password : 1; 			/**< 3.1 password */
			bool username : 1;			/**< 3.1 user name */
		} bits;
#endif
	} flags;	/**< connect flags byte */

	char *Protocol, /**< MQTT protocol name */
		*clientID,	/**< string client id */
        *willTopic,	/**< will topic */
        *willMsg;	/**< will payload */

	int keepAliveTimer;		/**< keepalive timeout value in seconds */
	unsigned char version;	/**< MQTT version number */
} Connect;

/**
 * Data for a willMessage.
 */
typedef struct
{
	char* topic;
	char* msg;
	int retained;
	int qos;
}willMessages;

/**
 * Data for a connack packet.
 */
typedef struct
{
	Header header; /**< MQTT header byte */
	union
	{
		unsigned char all;	/**< all connack flags */
#if defined(REVERSED)
		struct
		{
			unsigned int reserved : 7;	/**< message type nibble */
			bool sessionPresent : 1;    /**< was a session found on the server? */
		} bits;
#else
		struct
		{
			bool sessionPresent : 1;    /**< was a session found on the server? */
			unsigned int reserved : 7;	/**< message type nibble */
		} bits;
#endif
	} flags;	 /**< connack flags byte */
	char rc; /**< connack return code */
} Connack;


/**
 * Data for a publish packet.
 */
typedef struct
{
	Header header;	/**< MQTT header byte */
	char* topic;	/**< topic string */
	int topiclen;
	int msgId;		/**< MQTT message id */
	char* payload;	/**< binary payload, length delimited */
	int payloadlen;	/**< payload length */
} Publish;


/**
 * Data for one of the ack packets.
 */
typedef struct
{
	Header header;	/**< MQTT header byte */
	int msgId;		/**< MQTT message id */
} Ack;

/**
 * Class MQTT Packet
 */
class MQTTGWPacket
{
public:
	MQTTGWPacket();
	~MQTTGWPacket();
	int recv(Network* network);
	int send(Network* network);
	int getType(void);
	int getPacketData(unsigned char* buf);
	int getPacketLength(void);
	const char* getName(void);

	int getAck(Ack* ack);
	int getCONNACK(Connack* resp);
	int getSUBACK(unsigned short* msgId, unsigned char* rc);
	int getPUBLISH(Publish* pub);

	int setCONNECT(Connect* conect, unsigned char* username, unsigned char* password);
	int setPUBLISH(Publish* pub);
	int setAck(unsigned char msgType, unsigned short msgid);
	int setHeader(unsigned char msgType);
	int setSUBSCRIBE(const char* topic, unsigned char qos, unsigned short msgId);
	int setUNSUBSCRIBE(const char* topics, unsigned short msgid);
	char* getMsgId(char* buf);
	char* print(char* buf);
	MQTTGWPacket& operator =(MQTTGWPacket& packet);

private:
	void  clearData(void);
	Header	 _header;
	int _remainingLength;
	unsigned char* _data;
};

}

#endif /* MQTTGWPACKET_H_ */