SOME/IP SD server dead-lock

[langroodi]

Describe the bug
In some situation (probably a racing condition), the SOME/IP SD server stuck in the Main phase state, and it cannot get out of that state anymore, even by calling server Stop!

To Reproduce
It is a bit difficult to re-produce the error, but it seems sometimes stopping occurs before starting the server. The best way to debug sequence is to analyze the code itself.

Expected behavior
The server should be gracefully stop event the Stop function is called explicitly or the server destructor is being invoked.

Additional context (please complete the following information):

• Linux Distribution and Version: Ubuntu 20.04
• CMake Version: 3.14
• Compiler: GCC 9.3.0

[langroodi]

After a modification on the SOME/IP SD client, the stop mechanism dead-lock still can occur in the following unit tests sequence:

56/84 Test #56: SomeIpSdTest.ClientStart ...........................   Passed    0.70 sec
      Start 57: SomeIpSdTest.StartScenario
Error: The operation was canceled.

,

 59/104 Test  #59: SomeIpSdTest.ServerStopScenario ....................   Passed    0.81 sec
        Start  60: SomeIpSdTest.StopScenario

and

 57/133 Test  #57: SomeIpSdTest.StartScenario .........................***Exception: SegFault  0.89 sec
        Start  58: SomeIpSdTest.ClientStopScenario

[langroodi]

After 1ac136b commit, the issue is seen again once at 54: SomeIpSdTest.ClientStart.