IotMqtt_DeserializeResponse

Deserialize incoming ack packets.

IotMqttError_t IotMqtt_DeserializeResponse( IotMqttPacketInfo_t * pMqttPacket );

Parameters

[in,out]

pMqttPacket

The caller of this API sets type, remainingLength and pRemainingData. On success, packetIdentifier will be set.

Returns

One of the following:

• IOT_MQTT_SUCCESS
• IOT_MQTT_BAD_RESPONSE
• IOT_MQTT_SERVER_REFUSED

Note

This call is part of serializer API used for implementing light-weight MQTT client.

Example

// Example below shows how  IotMqtt_DeserializeResponse() is used to process unsubscribe ack.
// xMQTTSocket here is posix socket created and connected to MQTT broker outside of this function.
void processUnsubscribeAck( int xMQTTSocket )
{
     IotMqttError_t xResult;
     IotMqttPacketInfo_t xIncomingPacket;

     xResult = IotMqtt_GetIncomingMQTTPacketTypeAndLength( &xIncomingPacket, getNextByte, ( void * ) xMQTTSocket );
    IotMqtt_Assert( xResult == IOT_MQTT_SUCCESS );
    IotMqtt_Assert( xIncomingPacket.type == MQTT_PACKET_TYPE_UNSUBACK );
    IotMqtt_Assert( xIncomingPacket.remainingLength <= sizeof( ucSharedBuffer ) );

    // Receive the remaining bytes.
    if( recv( xMQTTSocket, ( void * ) ucSharedBuffer, xIncomingPacket.remainingLength, 0 ) == xIncomingPacket.remainingLength )
    {
        xIncomingPacket.pRemainingData = ucSharedBuffer;

        if( IotMqtt_DeserializeResponse( &xIncomingPacket ) != IOT_MQTT_SUCCESS )
        {
            xResult = IOT_MQTT_BAD_RESPONSE;
        }
    }
    else
    {
        xResult = IOT_MQTT_NETWORK_ERROR;
    }
     IotMqtt_Assert( xResult == IOT_MQTT_SUCCESS );
}