Method enable

dds/DCPS/DataReaderImpl.cpp:1101–1293

#endif // !defined (DDS_HAS_MINIMUM_BIT)

DDS::ReturnCode_t
DataReaderImpl::enable()
{
  // According to spec:
  // - Calling enable on an already enabled Entity has no effect and returns OK.
  // - Calling enable on an Entity whose factory is not enabled will fail
  //   and return PRECONDITION_NOT_MET.

  if (this->is_enabled()) {
    return DDS::RETCODE_OK;
  }

  RcHandle<SubscriberImpl> subscriber = get_subscriber_servant();
  if (!subscriber) {
    return DDS::RETCODE_ERROR;
  }

  if (!subscriber->is_enabled()) {
    return DDS::RETCODE_PRECONDITION_NOT_MET;
  }

  if (topic_servant_ && !topic_servant_->is_enabled()) {
    return DDS::RETCODE_PRECONDITION_NOT_MET;
  }

  RcHandle<DomainParticipantImpl> participant = participant_servant_.lock();
  if (participant) {
    dp_id_ = participant->get_id();
  }

  if (topic_servant_) {
    set_reader_effective_data_rep_qos(qos_.representation.value);
    if (!topic_servant_->check_data_representation(qos_.representation.value, false)) {
      return DDS::RETCODE_ERROR;
    }
  }

  if (qos_.history.kind == DDS::KEEP_ALL_HISTORY_QOS) {
    // The spec says qos_.history.depth is "has no effect"
    // when history.kind = KEEP_ALL so use max_samples_per_instance
    depth_ = qos_.resource_limits.max_samples_per_instance;

  } else { // qos_.history.kind == DDS::KEEP_LAST_HISTORY_QOS
    depth_ = qos_.history.depth;
  }

  if (depth_ == DDS::LENGTH_UNLIMITED) {
    // DDS::LENGTH_UNLIMITED is negative so make it a positive
    // value that is, for all intents and purposes, unlimited
    // and we can use it for comparisons.
    // WARNING: The client risks running out of memory in this case.
    depth_ = ACE_INT32_MAX;
  }

  if (qos_.resource_limits.max_samples != DDS::LENGTH_UNLIMITED) {
    n_chunks_ = static_cast<size_t>(qos_.resource_limits.max_samples);
  }