/// <summary>
/// Ensures the monitoring process is restarted if it crashed.
/// </summary>
/// <param name="parameter">The monitoring process.</param>
private static void ExecuteSymmetricWatch(object?parameter)
{
// Wait a bit to ensure the new process is started.
// A proper synchronization would be preferable, but at this point I'm too lazy.
Thread.Sleep(1000);
Monitoring Monitoring = (Monitoring)parameter !;
Debug.Assert(Monitoring.MonitorProcess != null);
Debug.Assert(Monitoring.CancelEvent != null);
#pragma warning disable CS8604 // Possible null reference argument.
ExecuteSymmetricWatch(Monitoring, Monitoring.MonitorProcess, Monitoring.CancelEvent);
#pragma warning restore CS8604 // Possible null reference argument.
}
/// <summary>
/// Installs the monitor.
/// </summary>
/// <returns>True if successful; False otherwise and <see cref="LastError"/> contains the error.</returns>
public bool ZombifyMe()
{
Monitoring NewMonitoring = new Monitoring()
{
ClientName = ClientName, Delay = Delay, WatchingMessage = WatchingMessage, RestartMessage = RestartMessage, Flags = Flags, IsSymmetric = IsSymmetric, AliveTimeout = AliveTimeout, MonitorFolder = MonitorFolder
};
Debug.Assert(NewMonitoring.CancelEvent == null);
bool Result = ZombifyMeInternal(NewMonitoring, out Errors Error);
CancelEvent = NewMonitoring.CancelEvent;
LastError = Error;
return(Result);
}
/// <summary>
/// Ensures the monitoring process is restarted if it crashed.
/// </summary>
/// <param name="monitoring">The monitoring information.</param>
/// <param name="monitorProcess">The monitoring process.</param>
/// <param name="cancelEvent">The cancellation event.</param>
private static void ExecuteSymmetricWatch(Monitoring monitoring, Process monitorProcess, EventWaitHandle cancelEvent)
{
TimeSpan AliveTimeout = monitoring.AliveTimeout;
Debug.Assert(AliveTimeout > TimeSpan.Zero);
bool IsAlive = true;
AliveWatch.Start();
while (IsAlive)
{
if (AliveWatch.Elapsed >= AliveTimeout)
{
break;
}
if (cancelEvent.WaitOne(SharedDefinitions.CheckInterval))
{
break;
}
IsAlive = !monitorProcess.HasExited;
if (!IsAlive)
{
using (monitorProcess)
{
}
// Wait the same delay as if restarting the original process.
Thread.Sleep(monitoring.Delay);
ZombifyMeInternal(monitoring, out _);
}
}
}
/// <summary>
/// Starts a thread to ensure the monitoring process is restarted if it crashed.
/// </summary>
/// <param name="monitoring">Monitoring parameters.</param>
private static void StartSymmetricWatch(Monitoring monitoring)
{
Thread NewThread = new Thread(ExecuteSymmetricWatch);
NewThread.Start(monitoring);
}
private static bool ZombifyMeInternal(Monitoring monitoring, out Errors error)
{
error = Errors.Success;
if (!LoadMonitor(monitoring.MonitorFolder, out string MonitorProcessFileName))
{
error = Errors.UnableToLoadSource;
return(false);
}
#if NET48
int ProcessId = Process.GetCurrentProcess().Id;
#else
int ProcessId = Environment.ProcessId;
#endif
Contracts.Contract.RequireNotNull(Assembly.GetEntryAssembly(), out Assembly EntryAssembly);
string ClientExePath = EntryAssembly.Location;
string ArgsText = string.Empty;
if (monitoring.Flags.HasFlag(Flags.ForwardArguments))
{
// Accumulate arguments in a single string.
string[] Args = Environment.GetCommandLineArgs();
for (int Index = 1; Index < Args.Length; Index++)
{
string Arg = Args[Index];
if (ArgsText.Length > 0)
{
ArgsText += " ";
}
ArgsText += Arg;
}
}
long DelayTicks = monitoring.Delay.Ticks;
monitoring.CancelEvent = new EventWaitHandle(false, EventResetMode.ManualReset, SharedDefinitions.GetCancelEventName(monitoring.ClientName));
// Use this impossible value as a hack to fail the launch.
if (monitoring.Delay == TimeSpan.MinValue)
{
MonitorProcessFileName = string.Empty;
}
// Start the monitoring process.
// Don't dispose of it, it's passed to another thread.
Process MonitorProcess = new Process
{
StartInfo =
{
FileName = MonitorProcessFileName,
Arguments = $"{ProcessId} \"{ClientExePath}\" \"{ArgsText}\" \"{monitoring.ClientName}\" {DelayTicks} \"{monitoring.WatchingMessage}\" \"{monitoring.RestartMessage}\" {(int)monitoring.Flags}",
UseShellExecute = false,
CreateNoWindow = true,
},
};
bool Result;
try
{
Result = MonitorProcess.Start();
}
catch
{
Result = false;
}
if (!Result)
{
error = Errors.MonitorNotStarted;
monitoring.MonitorProcess = null;
}
else
{
monitoring.MonitorProcess = MonitorProcess;
if (monitoring.IsSymmetric && monitoring.AliveTimeout > TimeSpan.Zero)
{
StartSymmetricWatch(monitoring);
}
}
return(Result);
}
