add watchdog timer to bsnes process to make sure they dont accumulate when the frontend terminates oddly

BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesApi.cs

@@ -34,6 +34,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 		
 		string InstanceName;
 		Process process;
+		System.Threading.EventWaitHandle watchdogEvent;
 		NamedPipeServerStream pipe;
 		BinaryWriter bwPipe;
 		BinaryReader brPipe;
@@ -96,6 +97,13 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 
 			pipe = new NamedPipeServerStream(pipeName, PipeDirection.InOut, 1, PipeTransmissionMode.Byte, PipeOptions.None, 1024 * 1024, 1024);
 
+			//slim chance this might be useful sometimes:
+			//http://stackoverflow.com/questions/2590334/creating-a-cross-process-eventwaithandle
+			//create an event for the child process to monitor with a watchdog, to make sure it terminates when the emuhawk process terminates.
+			//NOTE: this is alarming! for some reason .net releases this event when it gets finalized, instead of when i (dont) dispose it.
+			bool createdNew;
+			watchdogEvent = new System.Threading.EventWaitHandle(false, System.Threading.EventResetMode.AutoReset, InstanceName + "-event", out createdNew);
+
 			process = new Process();
 			process.StartInfo.WorkingDirectory = Path.GetDirectoryName(exePath);
 			process.StartInfo.FileName = exePath;
@@ -134,6 +142,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 
 		public void Dispose()
 		{
+			watchdogEvent.Dispose();
 			process.Kill();
 			process.Dispose();
 			process = null;

libsnes/bsnes/target-libsnes/libsnes_pwrap.cpp

@@ -342,10 +342,51 @@ public:
 	}
 }; //class IPCRingBuffer
 
+
+class Watchdog
+{
+public:
+	void Start(const char* _eventName)
+	{
+		HANDLE thread = CreateThread( NULL, 0, (LPTHREAD_START_ROUTINE)&ThreadProc, this, 0, NULL);
+		SetThreadPriority(thread,THREAD_PRIORITY_LOWEST);
+		eventName = _eventName;
+	}
+
+private:
+
+	std::string eventName;
+
+
+	static DWORD ThreadProc(LPVOID lpParam)
+	{
+		Watchdog* w = (Watchdog*)lpParam;
+		for(;;)
+		{
+			//only check once per second
+			Sleep(1000);
+
+			//try opening the handle. if its gone, the process is gone
+			HANDLE hEvent = OpenEvent(SYNCHRONIZE  | EVENT_ALL_ACCESS, FALSE, w->eventName.c_str());
+			
+			//printf("event handle: %08X (%d)\n",hEvent,hEvent?0:GetLastError()); //debugging
+			
+			//handle was gone, terminate process
+			if(hEvent == 0)
+			{
+				TerminateProcess(INVALID_HANDLE_VALUE,0);
+			}
+
+			CloseHandle(hEvent);
+		}
+	}
+}; //class Watchdog
+
 static bool bufio = false;
 static IPCRingBuffer *rbuf = NULL, *wbuf = NULL;
 
-HANDLE hPipe, hMapFile;
+Watchdog s_Watchdog;
+HANDLE hPipe, hMapFile, hEvent;
 void* hMapFilePtr;
 static bool running = false;
 
@@ -1199,7 +1240,9 @@ int xmain(int argc, char** argv)
 	}
 
 	char pipename[256];
+	char eventname[256];
 	sprintf(pipename, "\\\\.\\Pipe\\%s",argv[1]);
+	sprintf(eventname, "%s-event",argv[1]);
 
 	if(!strncmp(argv[1],"console",7))
 	{
@@ -1207,6 +1250,9 @@ int xmain(int argc, char** argv)
 	}
 
 	printf("pipe: %s\n",pipename);
+	printf("event: %s\n",eventname);
+
+	s_Watchdog.Start(eventname);
 
 	hPipe = CreateFile(pipename, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);