/**
* Returns the last written value written to this port, in case it is
* kept by this port, otherwise, returns a default T().
* @return The last written value or T().
*/
T getLastWrittenValue() const
{
typename internal::AssignableDataSource<T>::shared_ptr last_written_value = this->last_written_value;
if (written && last_written_value)
return last_written_value->get();
else return T();
}
virtual bool connectionAdded( base::ChannelElementBase::shared_ptr channel_input, ConnPolicy const& policy ) {
// Initialize the new channel with last written data if requested
// (and available)
// This this the input channel element of the whole connection
typename base::ChannelElement<T>::shared_ptr channel_el_input =
static_cast< base::ChannelElement<T>* >(channel_input.get());
if (written)
{
typename internal::AssignableDataSource<T>::shared_ptr last_written_value = this->last_written_value;
if (last_written_value)
{
T sample = last_written_value->get();
if ( channel_el_input->data_sample(sample) ) {
if ( policy.init )
return channel_el_input->write(sample);
return true;
} else {
Logger::In in("OutputPort");
log(Error) << "Failed to pass data sample to data channel. Aborting connection."<<endlog();
return false;
}
}
}
// even if we're not written, test the connection with a default sample.
return channel_el_input->data_sample( T() );
}
/**
* Reads the last written value written to this port, in case it is
* kept by this port, otherwise, returns false.
* @param sample The data sample to store the value into.
* @return true if it could be retrieved, false otherwise.
*/
bool getLastWrittenValue(T& sample) const
{
typename internal::AssignableDataSource<T>::shared_ptr last_written_value = this->last_written_value;
if (written && last_written_value)
{
sample = last_written_value->get();
return true;
}
return false;
}
