mqtt.h

Go to the documentation of this file.

#pragma once
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>

// TYPES

typedef union net_mqtt_t {
  uintptr_t _align; // ensure suitable alignment for internal state
  uint8_t opaque[128];
} net_mqtt_t;

typedef enum {
  net_mqtt_status_connected_t =
      (1 << 0), 
  net_mqtt_status_disconnected_t =
      (1 << 1), 
  net_mqtt_status_dns_error_t = (1 << 2), 
  net_mqtt_status_protocol_error_t =
      (1 << 3), 
  net_mqtt_status_auth_error_t =
      (1
       << 4), 
  net_mqtt_status_timeout_t =
      (1 << 5), 
  net_mqtt_status_error_t =
      (1 << 6), 
} net_mqtt_status_t;

typedef void (*net_mqtt_connect_callback_t)(net_mqtt_t *mqtt,
                                            net_mqtt_status_t status,
                                            void *user_data);

// LIFECYCLE

net_mqtt_t net_mqtt_init(net_mqtt_connect_callback_t connect, void *user_data);

bool net_mqtt_valid(net_mqtt_t *mqtt);

void net_mqtt_finalize(net_mqtt_t *mqtt);

bool net_mqtt_connect(net_mqtt_t *mqtt, const char *hostname, uint16_t port,
                      const char *client_id, const char *user,
                      const char *password, uint16_t keepalive_secs,
                      const char *will_topic, const char *will_message);

bool net_mqtt_disconnect(net_mqtt_t *mqtt);

// METHODS

bool net_mqtt_publish(net_mqtt_t *mqtt, const char *topic, const void *data,
                      size_t size, uint8_t qos);

static inline bool net_mqtt_publish_str(net_mqtt_t *mqtt, const char *topic,
                                        const char *str, uint8_t qos) {
  return net_mqtt_publish(mqtt, topic, str, strlen(str), qos);
}

bool net_mqtt_subscribe(net_mqtt_t *mqtt, const char *topic, uint8_t qos);

/*
// Future API (publish/subscribe):
// The following functions are planned and will follow the same asynchronous
// completion model. They are left commented-out to document the intended
// surface while implementation stabilizes.


bool net_mqtt_unsubscribe(net_mqtt_t *mqtt, const char *topic);
*/