int mqtt_client_unsubscribe()

in src/mqtt_client.c [1250:1296]
41 lines of code
8 McCabe index (conditional complexity)

int mqtt_client_unsubscribe(MQTT_CLIENT_HANDLE handle, uint16_t packetId, const char** unsubscribeList, size_t count)
{
    int result;
    MQTT_CLIENT* mqtt_client = (MQTT_CLIENT*)handle;
    if (mqtt_client == NULL || unsubscribeList == NULL || count == 0 || packetId == 0)
    {
        /*Codes_SRS_MQTT_CLIENT_07_016: [If any of the parameters handle, unsubscribeList is NULL or count is 0 then mqtt_client_unsubscribe shall return a non-zero value.]*/
        LogError("Invalid parameter specified mqtt_client: %p, unsubscribeList: %p, count: %lu, packetId: %d", mqtt_client, unsubscribeList, (unsigned long)count, packetId);
        result = MU_FAILURE;
    }
    else
    {
        STRING_HANDLE trace_log = construct_trace_log_handle(mqtt_client);

        BUFFER_HANDLE unsubPacket = mqtt_codec_unsubscribe(packetId, unsubscribeList, count, trace_log);
        if (unsubPacket == NULL)
        {
            /*Codes_SRS_MQTT_CLIENT_07_017: [If any failure is encountered then mqtt_client_unsubscribe shall return a non-zero value.]*/
            LogError("Error: mqtt_codec_unsubscribe failed");
            result = MU_FAILURE;
        }
        else
        {
            mqtt_client->packetState = UNSUBSCRIBE_TYPE;

            size_t size = BUFFER_length(unsubPacket);
            /*Codes_SRS_MQTT_CLIENT_07_018: [On success mqtt_client_unsubscribe shall send the MQTT SUBCRIBE packet to the endpoint.]*/
            if (sendPacketItem(mqtt_client, BUFFER_u_char(unsubPacket), size) != 0)
            {
                /*Codes_SRS_MQTT_CLIENT_07_017: [If any failure is encountered then mqtt_client_unsubscribe shall return a non-zero value.].]*/
                LogError("Error: mqtt_client_unsubscribe send failed");
                result = MU_FAILURE;
            }
            else
            {
                log_outgoing_trace(mqtt_client, trace_log);
                result = 0;
            }
            BUFFER_delete(unsubPacket);
        }
        if (trace_log != NULL)
        {
            STRING_delete(trace_log);
        }
    }
    return result;
}