Mbed OS Reference | mqtt.h Source File

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 /**
  * @file
  * MQTT client
  */
 
 /*
  * Copyright (c) 2016 Erik Andersson
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *
  * 1. Redistributions of source code must retain the above copyright notice,
  *    this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright notice,
  *    this list of conditions and the following disclaimer in the documentation
  *    and/or other materials provided with the distribution.
  * 3. The name of the author may not be used to endorse or promote products
  *    derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  * OF SUCH DAMAGE.
  *
  * This file is part of the lwIP TCP/IP stack.
  *
  * Author: Erik Andersson
  *
  */
 #ifndef LWIP_HDR_APPS_MQTT_CLIENT_H
 #define LWIP_HDR_APPS_MQTT_CLIENT_H
 
 #include "lwip/apps/mqtt_opts.h"
 #include "lwip/err.h"
 #include "lwip/ip_addr.h"
 #include "lwip/prot/iana.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 typedef struct mqtt_client_s mqtt_client_t;
 
 #if LWIP_ALTCP && LWIP_ALTCP_TLS
 struct altcp_tls_config;
 #endif
 
 /** @ingroup mqtt
  * Default MQTT port (non-TLS) */
 #define MQTT_PORT     LWIP_IANA_PORT_MQTT
 /** @ingroup mqtt
  * Default MQTT TLS port */
 #define MQTT_TLS_PORT LWIP_IANA_PORT_SECURE_MQTT
 
 /*---------------------------------------------------------------------------------------------- */
 /* Connection with server */
 
 /**
  * @ingroup mqtt
  * Client information and connection parameters */
 struct mqtt_connect_client_info_t {
   /** Client identifier, must be set by caller */
   const char *client_id;
   /** User name, set to NULL if not used */
   const char* client_user;
   /** Password, set to NULL if not used */
   const char* client_pass;
   /** keep alive time in seconds, 0 to disable keep alive functionality*/
   u16_t keep_alive;
   /** will topic, set to NULL if will is not to be used,
       will_msg, will_qos and will retain are then ignored */
   const char* will_topic;
   /** will_msg, see will_topic */
   const char* will_msg;
   /** will_qos, see will_topic */
   u8_t will_qos;
   /** will_retain, see will_topic */
   u8_t will_retain;
 #if LWIP_ALTCP && LWIP_ALTCP_TLS
   /** TLS configuration for secure connections */
   struct altcp_tls_config *tls_config;
 #endif
 };
 
 /**
  * @ingroup mqtt
  * Connection status codes */
 typedef enum
 {
   /** Accepted */
   MQTT_CONNECT_ACCEPTED                 = 0,
   /** Refused protocol version */
   MQTT_CONNECT_REFUSED_PROTOCOL_VERSION = 1,
   /** Refused identifier */
   MQTT_CONNECT_REFUSED_IDENTIFIER       = 2,
   /** Refused server */
   MQTT_CONNECT_REFUSED_SERVER           = 3,
   /** Refused user credentials */
   MQTT_CONNECT_REFUSED_USERNAME_PASS    = 4,
   /** Refused not authorized */
   MQTT_CONNECT_REFUSED_NOT_AUTHORIZED_  = 5,
   /** Disconnected */
   MQTT_CONNECT_DISCONNECTED             = 256,
   /** Timeout */
   MQTT_CONNECT_TIMEOUT                  = 257
 } mqtt_connection_status_t;
 
 /**
  * @ingroup mqtt
  * Function prototype for mqtt connection status callback. Called when
  * client has connected to the server after initiating a mqtt connection attempt by
  * calling mqtt_client_connect() or when connection is closed by server or an error
  *
  * @param client MQTT client itself
  * @param arg Additional argument to pass to the callback function
  * @param status Connect result code or disconnection notification @see mqtt_connection_status_t
  *
  */
 typedef void (*mqtt_connection_cb_t)(mqtt_client_t *client, void *arg, mqtt_connection_status_t status);
 
 
 /**
  * @ingroup mqtt
  * Data callback flags */
 enum {
   /** Flag set when last fragment of data arrives in data callback */
   MQTT_DATA_FLAG_LAST = 1
 };
 
 /** 
  * @ingroup mqtt
  * Function prototype for MQTT incoming publish data callback function. Called when data
  * arrives to a subscribed topic @see mqtt_subscribe
  *
  * @param arg Additional argument to pass to the callback function
  * @param data User data, pointed object, data may not be referenced after callback return,
           NULL is passed when all publish data are delivered
  * @param len Length of publish data fragment
  * @param flags MQTT_DATA_FLAG_LAST set when this call contains the last part of data from publish message
  *
  */
 typedef void (*mqtt_incoming_data_cb_t)(void *arg, const u8_t *data, u16_t len, u8_t flags);
 
 
 /** 
  * @ingroup mqtt
  * Function prototype for MQTT incoming publish function. Called when an incoming publish
  * arrives to a subscribed topic @see mqtt_subscribe
  *
  * @param arg Additional argument to pass to the callback function
  * @param topic Zero terminated Topic text string, topic may not be referenced after callback return
  * @param tot_len Total length of publish data, if set to 0 (no publish payload) data callback will not be invoked
  */
 typedef void (*mqtt_incoming_publish_cb_t)(void *arg, const char *topic, u32_t tot_len);
 
 
 /**
  * @ingroup mqtt
  * Function prototype for mqtt request callback. Called when a subscribe, unsubscribe
  * or publish request has completed
  * @param arg Pointer to user data supplied when invoking request
  * @param err ERR_OK on success
  *            ERR_TIMEOUT if no response was received within timeout,
  *            ERR_ABRT if (un)subscribe was denied
  */
 typedef void (*mqtt_request_cb_t)(void *arg, err_t err);
 
 
 err_t mqtt_client_connect(mqtt_client_t *client, const ip_addr_t *ipaddr, u16_t port, mqtt_connection_cb_t cb, void *arg,
                    const struct mqtt_connect_client_info_t *client_info);
 
 void mqtt_disconnect(mqtt_client_t *client);
 
 mqtt_client_t *mqtt_client_new(void);
 void mqtt_client_free(mqtt_client_t* client);
 
 u8_t mqtt_client_is_connected(mqtt_client_t *client);
 
 void mqtt_set_inpub_callback(mqtt_client_t *client, mqtt_incoming_publish_cb_t,
                              mqtt_incoming_data_cb_t data_cb, void *arg);
 
 err_t mqtt_sub_unsub(mqtt_client_t *client, const char *topic, u8_t qos, mqtt_request_cb_t cb, void *arg, u8_t sub);
 
 /** @ingroup mqtt
  *Subscribe to topic */
 #define mqtt_subscribe(client, topic, qos, cb, arg) mqtt_sub_unsub(client, topic, qos, cb, arg, 1)
 /** @ingroup mqtt
  *  Unsubscribe to topic */
 #define mqtt_unsubscribe(client, topic, cb, arg) mqtt_sub_unsub(client, topic, 0, cb, arg, 0)
 
 err_t mqtt_publish(mqtt_client_t *client, const char *topic, const void *payload, u16_t payload_length, u8_t qos, u8_t retain,
                                     mqtt_request_cb_t cb, void *arg);
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif /* LWIP_HDR_APPS_MQTT_CLIENT_H */
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