public static void StartWatchdogForPid()

in rd-net/Lifetimes/Diagnostics/ProcessWatchdog.cs [74:131]
48 lines of code
7 McCabe index (conditional complexity)

    public static void StartWatchdogForPid(Options options)
    {
      var pid = options.Pid;
      var watchThread = new Thread(() =>
      {
        var lifetime = options.Lifetime;
        var beforeProcessKill = options.BeforeProcessKill;
        var gracefulShutdownPeriod = options.GracefulShutdownPeriod;
        var killCurrentProcess = options.KillCurrentProcess;

        ourLogger.Info($"Monitoring parent process PID:{pid}");

        var useWinApi = true;

        while (true)
        {
          if (lifetime.IsNotAlive)
          {
            ourLogger.Info($"Monitoring of process {pid} stopped by lifetime termination");
            return;
          }
          if (!ProcessExists(pid, ref useWinApi))
          {
            var exitMsg = $"Parent process PID:{pid} has quit, killing ourselves via Process.Kill";
            try
            {
              LogLog.Error(exitMsg);
              ourLogger.Error(exitMsg);
              
              beforeProcessKill?.Invoke();
              
              if (gracefulShutdownPeriod.HasValue)
              {
                var waitingMessage = $"Waiting for grace period: {gracefulShutdownPeriod.Value}";
                LogLog.Info(waitingMessage);
                ourLogger.Info(waitingMessage);
                
                Thread.Sleep(gracefulShutdownPeriod.Value);
              }
            }
            catch
            {
              // ignored
            }

            if (killCurrentProcess != null)
              killCurrentProcess();
            else
              Process.GetCurrentProcess().Kill();
            return;
          }

          Thread.Sleep(DELAY_BEFORE_RETRY);
        }
      }) {IsBackground = true, Name = "WatchParentPid:" + pid};

      watchThread.Start();
    }