static int send_mqtt_message(PROV_TRANSPORT_MQTT_INFO* mqtt_info, const char* msg_topic)
{
int result;
MQTT_MESSAGE_HANDLE msg_handle = NULL;
if ((msg_handle = mqttmessage_create(get_next_packet_id(mqtt_info), msg_topic, DELIVER_AT_MOST_ONCE, NULL, 0)) == NULL)
{
LogError("Failed creating mqtt message");
result = __FAILURE__;
}
else
{
if (mqtt_client_publish(mqtt_info->mqtt_client, msg_handle) != 0)
{
LogError("Failed publishing client message");
result = __FAILURE__;
}
else
{
result = 0;
}
mqttmessage_destroy(msg_handle);
}
return result;
}
int mqtt_unsubscribe(mqtt_client_t* c, const char* topicFilter)
{
int rc = MQTT_FAILURE;
mqtt_timer_t timer;
mqtt_string_t topic = mqtt_string_initializer;
topic.cstring = (char *)topicFilter;
int len = 0;
mqtt_timer_init(&timer);
mqtt_timer_countdown_ms(&timer, c->command_timeout_ms);
if (!c->isconnected)
goto exit;
if ((len = mqtt_serialize_unsubscribe(c->buf, c->buf_size, 0, get_next_packet_id(c), 1, &topic)) <= 0)
goto exit;
if ((rc = send_packet(c, len, &timer)) != MQTT_SUCCESS) // send the subscribe packet
goto exit; // there was a problem
if (waitfor(c, MQTTPACKET_UNSUBACK, &timer) == MQTTPACKET_UNSUBACK)
{
unsigned short mypacketid; // should be the same as the packetid above
if (mqtt_deserialize_unsuback(&mypacketid, c->readbuf, c->readbuf_size) == 1)
rc = 0;
}
else
rc = MQTT_FAILURE;
exit:
return rc;
}
int mqtt_subscribe(mqtt_client_t* c, const char* topic, enum mqtt_qos qos, mqtt_message_handler_t handler)
{
int rc = MQTT_FAILURE;
mqtt_timer_t timer;
int len = 0;
mqtt_string_t topicStr = mqtt_string_initializer;
topicStr.cstring = (char *)topic;
mqtt_timer_init(&timer);
mqtt_timer_countdown_ms(&timer, c->command_timeout_ms);
if (!c->isconnected)
goto exit;
len = mqtt_serialize_subscribe(c->buf, c->buf_size, 0, get_next_packet_id(c), 1, &topicStr, (int*)&qos);
if (len <= 0)
goto exit;
if ((rc = send_packet(c, len, &timer)) != MQTT_SUCCESS) // send the subscribe packet
{
goto exit; // there was a problem
}
if (waitfor(c, MQTTPACKET_SUBACK, &timer) == MQTTPACKET_SUBACK) // wait for suback
{
int count = 0, grantedQoS = -1;
unsigned short mypacketid;
if (mqtt_deserialize_suback(&mypacketid, 1, &count, &grantedQoS, c->readbuf, c->readbuf_size) == 1)
rc = grantedQoS; // 0, 1, 2 or 0x80
if (rc != 0x80)
{
int i;
rc = MQTT_FAILURE;
for (i = 0; i < MQTT_MAX_MESSAGE_HANDLERS; ++i)
{
if (c->messageHandlers[i].topicFilter == 0)
{
c->messageHandlers[i].topicFilter = topic;
c->messageHandlers[i].fp = handler;
rc = 0;
break;
}
}
}
}
else
rc = MQTT_FAILURE;
exit:
return rc;
}
static int subscribe_to_topic(PROV_TRANSPORT_MQTT_INFO* mqtt_info)
{
int result;
SUBSCRIBE_PAYLOAD subscribe[SUBSCRIBE_TOPIC_COUNT];
subscribe[0].subscribeTopic = MQTT_SUBSCRIBE_TOPIC;
subscribe[0].qosReturn = DELIVER_AT_LEAST_ONCE;
if (mqtt_client_subscribe(mqtt_info->mqtt_client, get_next_packet_id(mqtt_info), subscribe, SUBSCRIBE_TOPIC_COUNT) != 0)
{
LogError("Failed subscribing to topic.");
result = __FAILURE__;
}
else
{
result = 0;
}
return result;
}
int mqtt_publish(mqtt_client_t* c, const char* topic, mqtt_message_t* message)
{
int rc = MQTT_FAILURE;
mqtt_timer_t timer;
mqtt_string_t topicStr = mqtt_string_initializer;
topicStr.cstring = (char *)topic;
int len = 0;
mqtt_timer_init(&timer);
mqtt_timer_countdown_ms(&timer, c->command_timeout_ms);
if (!c->isconnected)
goto exit;
if (message->qos == MQTT_QOS1 || message->qos == MQTT_QOS2)
message->id = get_next_packet_id(c);
len = mqtt_serialize_publish(c->buf, c->buf_size, 0, message->qos, message->retained, message->id,
topicStr, (unsigned char*)message->payload, message->payloadlen);
if (len <= 0)
goto exit;
if ((rc = send_packet(c, len, &timer)) != MQTT_SUCCESS) // send the subscribe packet
{
goto exit; // there was a problem
}
if (message->qos == MQTT_QOS1)
{
if (waitfor(c, MQTTPACKET_PUBACK, &timer) == MQTTPACKET_PUBACK)
{
// We still can receive from broker, treat as recoverable
c->fail_count = 0;
unsigned short mypacketid;
unsigned char dup, type;
if (mqtt_deserialize_ack(&type, &dup, &mypacketid, c->readbuf, c->readbuf_size) != 1)
rc = MQTT_FAILURE;
else
rc = MQTT_SUCCESS;
}
else
{
rc = MQTT_FAILURE;
}
}
else if (message->qos == MQTT_QOS2)
{
if (waitfor(c, MQTTPACKET_PUBCOMP, &timer) == MQTTPACKET_PUBCOMP)
{
// We still can receive from broker, treat as recoverable
c->fail_count = 0;
unsigned short mypacketid;
unsigned char dup, type;
if (mqtt_deserialize_ack(&type, &dup, &mypacketid, c->readbuf, c->readbuf_size) != 1)
rc = MQTT_FAILURE;
else
rc = MQTT_SUCCESS;
}
else
{
rc = MQTT_FAILURE;
}
}
exit:
return rc;
}
