netone backend with "-t 0" doesn't work correctly

[alowell-ssl]

Describe the bug

I have a netjack 1 setup between two hosts. On the slave machine, where I run "jackd -d netone", the JACK transport is slaved to the master, and I think this is the intended behavior. Trying to control the transport from the slave has no effect, and the transport on the slave follows the transport on the master.

In some situations, this might not be desirable. For example, I discovered that Bitwig on the slave machine will not roll its transport because it is unable to influence the JACK transport which is completely controlled by the master machine (and unfortunately it seems Bitwig cannot be configured to ignore the JACK transport when using its JACK backend). I noticed that the netone backend has a flag -t "Whether or not to slave the transport to the master transport.", which seemed like a way to work around this. Setting this to zero like "jackd -d netone -t 0", I found that the local transport is no longer slaved to the master, however the local transport on the slave is left in a non-functional state. I cannot get it to roll from Bitwig or even jack_transport.

Environment

JACK version: jackdmp version 1.9.21 tmpdir /dev/shm protocol 9

Operating system: Ubuntu 24.04.3 LTS

Installation: installed via apt package manager.

Steps to reproduce

1. Start a netjack master instance with "netsource -H slave_ip" once a jackd session is already running on the master.
2. On the slave machine, do "jackd -d netone -t 0" to start the netjack slave
3. On the slave machine, run jack_transport and enter the "play" command
4. On the slave machine, run jack_showtime and observe that the transport state is not "rolling"

[alowell-ssl]

I'm able to workaround this issue by doing the following in JackNetOneDriver::Initialize() (common/JackNetOneDriver.cpp):

fEngineControl->fTransport.SetNetworkSync(true);

to

if(netj.handle_transport_sync)                                                                                                                                                            
   fEngineControl->fTransport.SetNetworkSync(true);                                                                                                                                      
else                                                                                                                                                                                      
   fEngineControl->fTransport.SetNetworkSync(false);

With the above change, I'm able to exchange audio with the netjack master AND control the transport locally when I pass the -t 0 to the netone backend.