Linux: Prevent infrequent freeze/crash when closing

GUI.NET/Forms/frmMain.cs

@@ -242,6 +242,17 @@ namespace Mesen.GUI.Forms
 				return;
 			}
 
+			if(!_shuttingDown && Program.IsMono) {
+				//This appears to prevent Mono from locking up when closing the form
+				Task.Run(() => {
+					StopEmu();
+					_shuttingDown = true;
+					this.BeginInvoke((Action)(() => this.Close()));
+				});
+				e.Cancel = true;
+				return;
+			}
+
 			_shuttingDown = true;
 
 			//Stop menu update timer, and process all pending events before stopping the core

Linux/LinuxKeyManager.cpp

@@ -270,6 +270,7 @@ LinuxKeyManager::LinuxKeyManager()
 LinuxKeyManager::~LinuxKeyManager()
 {
 	_stopUpdateDeviceThread = true;
+	_stopSignal.Signal();
 	_updateDeviceThread.join();
 }
 
@@ -387,7 +388,7 @@ void LinuxKeyManager::StartUpdateDeviceThread()
 				Console::Resume();
 			}
 
-			std::this_thread::sleep_for(std::chrono::duration<int, std::milli>(2000));
+			_stopSignal.Wait(2000);
 		}
 	});
 }	

Linux/LinuxKeyManager.h

@@ -3,6 +3,7 @@
 #include <vector>
 #include <thread>
 #include "../Core/IKeyManager.h"
+#include "../Utilities/AutoResetEvent.h"
 
 class LinuxGameController;
 
@@ -24,6 +25,7 @@ private:
 
 	std::thread _updateDeviceThread;
 	atomic<bool> _stopUpdateDeviceThread; 
+	AutoResetEvent _stopSignal;
 	bool _disableAllKeys;
 
 	void StartUpdateDeviceThread();