CIM Port Scanning and usage causes AsTeRICS to freeze or crash

[klues]

We encountered some strange situations, where CIM Port scanning or usage of CIM Ports caused AsTeRICS to crash. Unfortunately we could not reproduce all errors or causes of errors. These errors occur:

• endless exceptions if disconnecting a CIM device while using it
• freezing of AsTeRICS GUI after disconnecting a CIM device while using it, but also spontaneously on at random times
• rescanning on USB attach does not work properly

These issues should be resolved or at least improved.

[klues]

https://github.com/asterics/AsTeRICS/pull/221/files

changes in functionality:

• now there is a property CIM.mode.raw, default false, if set to true only raw connections can be used, but CIM scanning is used in order to get mapping cimID -> comPortName

other changes regarding performance and stability:

• CIMPortManager.rescan() is started in own thread, and therfore does not block starting of AsTeRICS. If a model wants to use a CIMPort, methods retrieving the ports are blocking until rescan has finished.
• sending of packets (sendPacket) is started in own threads and has a default timeout of 2 seconds -> prevents freezing of AsTeRICS if sendPacket fails
• improved handling of threads - e.g. waiting for threads to end before closing the port in CIMIdentifyPortController
• threads of controllers are closed if an IOException occurs and therefore do not produce endless exceptions
• numerous other small fixes and cleaning up of code

[klues]

Did tests with the following CIM devices:

• LIPMouse
• Accelerometer Sensor
• Digital IN
• HID actuator

Testing steps I did:

1. connected all devices, started ARE
2. all devices were found and listed after startup
3. set model Acceleration_test.acs as autostart
4. on ARE start, model start waits until rescan is finished - afterwards Acceleration_test.acs starts and works without errors
5. start/stop/redeploy of Acceleration_test.acs works without problems
6. furter tests:
   • DigitalIn_test.acs with digital in module
   • RemoteMouse_test.acs with HID actuator module (bluetooth)
   • start/stop/redeploy worked without problems
7. Started each of the test models mentioned above, unplugged the corresponding USB device -> no ARE freeze or shutdown, ports are correctly closed and redeploy of model shows error message, that device is not found.
8. Other models with connected devices still work, after another device was disconnected
9. Re-connected Accelerometer -> rescan triggered -> found it and Acceleration_test.acs works again
10. Reconnecting the other devices -> rescan triggered -> devices were not found.

So all looks good, except of (10). The reason for not finding a re-connected device again is probably that the close() method of the RXTX-library does not correclty close the device in every case and therefore rescan() fails because of an "already in use" error. After restarting ARE, the devices are found again, normally.

[klues]

merged https://github.com/asterics/AsTeRICS/pull/221 -> closing issue