YarpRobotLoggerDevice sets global blf factories in the costructor

[traversaro]

See

bipedal-locomotion-framework/devices/YarpRobotLoggerDevice/src/YarpRobotLoggerDevice.cpp

Lines 111 to 123 in 4ea3780

	YarpRobotLoggerDevice::YarpRobotLoggerDevice()
	: yarp::os::PeriodicThread(0.01, yarp::os::ShouldUseSystemClock::No)
	{
	// Use the yarp clock in blf
	BipedalLocomotion::System::ClockBuilder::setFactory(
	std::make_shared<BipedalLocomotion::System::YarpClockFactory>());
	// the logging message are streamed using yarp
	BipedalLocomotion::TextLogging::LoggerBuilder::setFactory(
	std::make_shared<BipedalLocomotion::TextLogging::YarpLoggerFactory>());
	m_sendDataRT = false;
	}

.

This works fine if the device is launched as part of a standalone yarprobotinterface process, but if this is done as part of a robotinterface instance created with the libYARP_robotinterface, what can happen is that the YARP libraries are unloaded, but the factories are never restored to the non-YARP ones, resulting in segmentation fault if the textlogging or clock functions are used.

[GiulioRomualdi]

Thanks for spotting it, what do you think is the correct solution?

[traversaro]

That is kind of a tricky one, as any kind of global state is always tricky to handle. Perhaps we could have an option to enable/disable setting this global state? It may be even more clean to have a dedicated device that only set the logger and the clock, but that would be a bit cumbersome as you would need to remember to insert it in any yarprobotinterface, while the option may be more easy to handle?