// before
static void get_sensor_data(size_t iteration,
                            size_t sensor_id,
                            float* value,
                            const char** name,
                            bool* need_output)
{
    *need_output = false;
    switch (sensor_id) {
    case 0:
        *value = get_sensor_A_value();
        *name = "A";
        *need_output = true;
        break;
    // 中略
    }
}
