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Cannot wait on a transparent proxy in ThreadPool nonblocking wait

Can I somehow register nonblocking handler on marshalled signal in different app domain?
I have a class that cannot be MarhsalByRef, yet I need to be able to call a method A on in in a different app domain D and then method B in the same app domain D.
This is could be easily solved by MarshalByRef - but I cannot use due to other code.
So I use a simple marshallable event and signal to the other app domain. I'd want to register a nonblocking handler in the other app domain - but it doesn't seem possible. I'm left with active wait?
Below is the repro:
[Serializable]
//this cannot be MarshalByRefObject
public class AppDomainTest
{
private readonly ManualResetEvent _mrse = new ManualResetEvent(false);
public static void Test()
{
AppDomainTest ap = new AppDomainTest();
Task.Factory.StartNew(() => ap.CreateDomainAndRun());
Thread.Sleep(1000);
ap.CallIntoDomain();
}
public void CreateDomainAndRun()
{
var otherDomain = AppDomain.CreateDomain("MyDomain", AppDomain.CurrentDomain.Evidence);
Task.Run(() => otherDomain.DoCallBack(RunInternal));
}
public void CallIntoDomain()
{
this._mrse.Set();
}
private void RunInternal()
{
//----------- HERE IS THE REPRO ---------------- //
//This crashes
//"Cannot wait on a transparent proxy"
//ThreadPool.RegisterWaitForSingleObject(_mrse, CancellationCallBack, null,
// Timeout.InfiniteTimeSpan, true);
Task.Factory.StartNew(() =>
{
//This works just fine
_mrse.WaitOne();
CallIntoDomainInternal();
}, TaskCreationOptions.LongRunning).Wait();
}
private void CancellationCallBack(object state, bool timedOut)
{
CallIntoDomainInternal();
}
private void CallIntoDomainInternal()
{
Console.WriteLine($"App domain: {AppDomain.CurrentDomain.FriendlyName}");
}
}
Registering callback with ThreadPool throws 'Cannot wait on a transparent proxy'. Active wait in task works just fine.

Raising Custom Class Events In Windows Service C#

I did write a windows service that can connect to a network device using a dll. so everything works fine, but The event handler does not work in win service! here is my code :
My Custom Class Code :
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace MyNewService
{
public class zkemkeeperHandler
{
public event EventHandler OnFinger;
public event EventHandler<VerifyEventArgs> OnVerify;
private System.Diagnostics.EventLog eventLog1 = new System.Diagnostics.EventLog();
public zkemkeeper.CZKEMClass axCZKEM1 = new zkemkeeper.CZKEMClass();
private bool bIsConnected = false;
private int iMachineNumber = 1;
public zkemkeeperHandler()
{
((System.ComponentModel.ISupportInitialize)(this.eventLog1)).BeginInit();
this.eventLog1.Log = "DoDyLog";
this.eventLog1.Source = "DoDyLogSource";
((System.ComponentModel.ISupportInitialize)(this.eventLog1)).EndInit();
eventLog1.WriteEntry("zkemkeeperHandler constructor");
}
public void startService()
{
eventLog1.WriteEntry("start service for (192.168.0.77:4370)");
bIsConnected = axCZKEM1.Connect_Net("192.168.0.77", Convert.ToInt32("4370"));
if (bIsConnected == true)
{
eventLog1.WriteEntry("bIsConnected == true !");
iMachineNumber = 1;
if (axCZKEM1.RegEvent(iMachineNumber, 65535))
{
this.axCZKEM1.OnFinger += new kemkeeper._IZKEMEvents_OnFingerEventHandler(axCZKEM1_OnFinger);
this.axCZKEM1.OnVerify += new zkemkeeper._IZKEMEvents_OnVerifyEventHandler(axCZKEM1_OnVerify);
//This Log Appears in Event Viewer
eventLog1.WriteEntry("Define events (OnFingers and OnVerify) !");
//This Line Fires Event in Service1.cs for testing event handler
Finger(EventArgs.Empty);
}
}
else
{
eventLog1.WriteEntry("Unable to connect the device");
}
}
public void stopService()
{
if (bIsConnected) {axCZKEM1.Disconnect(); bIsConnected = false;}
}
//This method doesn't run :(
private void axCZKEM1_OnFinger()
{
Finger(EventArgs.Empty);
}
//This method doesn't run too :(
private void axCZKEM1_OnVerify(int iUserID)
{
VerifyEventArgs args = new VerifyEventArgs();
args.UserID = iUserID;
Verify(args);
}
public class VerifyEventArgs : EventArgs
{
public int UserID { get; set; }
}
protected virtual void Finger(EventArgs e)
{
EventHandler handler = OnFinger;
if (handler != null)
handler(this, e);
}
protected virtual void Verify(VerifyEventArgs e)
{
EventHandler<VerifyEventArgs> handler = OnVerify;
if (handler != null)
handler(this, e);
}
}
}
My Main Service Class Code :
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.ServiceProcess;
using System.Linq;
using System.Threading;
namespace MyNewService
{
public class Service1 : System.ServiceProcess.ServiceBase
{
private System.Diagnostics.EventLog eventLog1;
private System.ComponentModel.Container components = null;
zkemkeeperHandler zkh;
public Service1()
{
InitializeComponent();
if (!System.Diagnostics.EventLog.SourceExists("DoDyLogSource"))
{
System.Diagnostics.EventLog.CreateEventSource("DoDyLogSource", "DoDyLog");
}
eventLog1.Source = "DoDyLogSource";
eventLog1.Log = "DoDyLog";
eventLog1.WriteEntry("Preparing to start service");
try
{
startZKHandler();
}
catch (Exception ex)
{
eventLog1.WriteEntry(ex.InnerException.Message);
}
}
private void startZKHandler()
{
eventLog1.WriteEntry("creating zkemkeeper handler class");
zkh = new zkemkeeperHandler();
zkh.OnFinger += OnFinger;
zkh.OnVerify += OnVerify;
zkh.startService();
}
private void stopZKHandler()
{
eventLog1.WriteEntry("Disconnecting from device (192.168.0.77)...");
zkh.stopService();
}
private void writeLog2DB(string message)
{
try
{
eventLog1.WriteEntry("writing to database");
DB.DBase.LogTable.AddObject(new LogTable
{
ID = ++DB.IDCounter,
deviceLog = message
});
DB.DBase.SaveChanges();
}
catch (Exception ex)
{
eventLog1.WriteEntry(ex.Message + " - " + ex.InnerException.Message);
}
this.EventLog.Log = "Event Stored in DB.";
}
// The main entry point for the process
static void Main()
{
System.ServiceProcess.ServiceBase[] ServicesToRun;
ServicesToRun = new System.ServiceProcess.ServiceBase[] { new MyNewService.Service1()};
System.ServiceProcess.ServiceBase.Run(ServicesToRun);
}
private void InitializeComponent()
{
this.eventLog1 = new System.Diagnostics.EventLog();
((System.ComponentModel.ISupportInitialize)(this.eventLog1)).BeginInit();
this.eventLog1.Log = "DoDyLog";
this.eventLog1.Source = "DoDyLogSource";
this.ServiceName = "MyNewService";
((System.ComponentModel.ISupportInitialize)(this.eventLog1)).EndInit();
}
protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
protected override void OnStart(string[] args)
{
// TODO: Add code here to start your service.
eventLog1.WriteEntry("my service started");
}
protected override void OnStop()
{
// TODO: Add code here to perform any tear-down necessary to stop your service.
eventLog1.WriteEntry("my service stoped");
stopZKHandler();
}
protected override void OnContinue()
{
eventLog1.WriteEntry("my service is continuing in working");
}
private void OnFinger(object sender, EventArgs e)
{
eventLog1.WriteEntry("Finger Event Raised");
}
private void OnVerify(object sender, zkemkeeperHandler.VerifyEventArgs e)
{
eventLog1.WriteEntry("Verify Event Raised");
}
}
}
What is my mistake? please help me!
The Windows Service that I wrote, can raise custom events but cannot raise my dll events!

I know this thread is old, but I had this problem yesterday, and now I have finally found a solution, after many hours wasted.
The problem is that, the COM object must be created from an STA Thread, and then, for the events to be dispatched correctly, the same STA thread (exactly the same) must be pumping COM messages. This can be done calling Application.DoEvents() in a loop or Application.Run().
So here is my working code (it works, even as a non-interactive Windows Service in Vista+, I am using Windows 8.1)
Thread createComAndMessagePumpThread = new Thread(() =>
{
this.Device = new CZKEMClass(); //Here create COM object
Application.Run();
});
createComAndMessagePumpThread.SetApartmentState(ApartmentState.STA);
createComAndMessagePumpThread.Start();
After the device gets created you can register the events from any thread, and they get dispatched by the STA thread, that created the COM object.
In Windows Forms application, this worked without doing this, because the STA main thread run the form calling Application.Run(Form). Application.Run() then dispatch events like COM events and Windows GUI events, so there is no need to to the trick above.

Reviving this question as I've just been dealing with a related one. Apparently, the OP is using some COM STA objects which need an STA thread and a functional message pump loop to operate properly. The Windows Service execution model doesn't have that by default. Visit the linked answer for more details.

You cannot use events in Windows Service. Exists several causes why not but I would like to offer a solution just for zkemkeeper:
ZK released a zkemkeeper.dll as COM object for working with Windows Application. All device events will fired and not raised in your application when you run it as windows service. Try to add a reference System.Windows.Forms to the project and after successfully connect add row:
Application.Run();

TCP listener not working when it is behind a load balancer

I have a TCP listener in a windows service that listens for any incoming TCP requests on a specific port and processes the message. It works fine when it is accessed directly. But once this is running behind a load balancer (in intranet), then it is not accepting any requests. I get errors like "unable to connect to remote server" OR "operation timed out". After a while the service terminates with "out of memory" exception. Please let me know what could be the reason for this. Pasting the code below. I even tried async mode as well (to avoid explicit thread launching). but that didn't help.
public class SampleListener: IDisposable
{
public delegate void JobRecieved(HttpMessage msg);
public event JobRecieved OnJobRecieved;
#region Property
private TcpListener _tcpListener;
private Thread _listenerThread;
public int Port { get; private set; }
public string Url
{
get
{
return new UriBuilder { Scheme = "http", Port = Port, Host = Dns.GetHostName() }.ToString();
}
}
#endregion
public SampleListener(int port)
{
Port = port;
}
~SampleListener()
{
DisposeImpl(false);
}
public void Start()
{
_tcpListener = new TcpListener(IPAddress.Any, Port);
_tcpListener.Start();
_listenerThread = new Thread(ListenCallback);
_listenerThread.Start();
}
public void ListenCallback()
{
try
{
while (true)
{
using (TcpClient client = _tcpListener.AcceptTcpClient())
using (var clientStream = client.GetStream())
{
var msg = new HttpMessage();
msg.Receive(clientStream);
SendOKResponse(client, "");
OnJobRecieved(msg);
client.Close();
}
}
}
catch (System.Net.Sockets.SocketException e)
{
// Expected, TcpClient.Stop called
}
catch (System.Threading.ThreadAbortException)
{
// Expected, thread going away
}
catch (System.IO.IOException)
{
// Expected, shutdown while reading
}
}
private void SendOKResponse(TcpClient tcpClient, String responseBody)
{
var response = new HttpMessage
{
Status = "200",
Reason = "OK",
Version = "HTTP/1.1"
};
response.Send(tcpClient.GetStream(), responseBody);
}
public void Shutdown()
{
lock (this)
{
if (_listenerThread != null)
{
_listenerThread.Abort();
_listenerThread = null;
}
if (_tcpListener != null)
{
_tcpListener.Stop();
_tcpListener.Server.Close();
_tcpListener = null;
}
}
}
#region IDisposable Members
private void DisposeImpl(Boolean bDisposing)
{
lock (this)
{
Shutdown();
}
}
public void Dispose()
{
GC.SuppressFinalize(this);
DisposeImpl(true);
}
#endregion
}

That's because NLB on Windows needs your application be a clustered one by default. And if it is not (which it is your case) you must use Sticky Sessions. Apparently your NLB is not using Sticky Sessions so requests may travel to different servers on each pass. That's why you get those exceptions (Take a look at this).
That happened to me on one of my own projects (a high performance TCP Server - the opposite of what you are doing).

Connecting Anonymous Pipe across processes gives Invalid Handle Error, I'm using System.Io.Pipes

I'm trying to put together a class to handle Ipc between processes using anonymous pipes provided by System.Io.Pipes.
The problem I'm having is that when I test the class using a single process the pipes set up correctly and I can send data between client and server without a problem. However, when I split the client and server into separate processes ( on the same machine ), the client is unable to connect to the end of the server pipe.
The error System.Io.Exception Invalid pipe handle is raised when call
_outboundPipeServerStream = new AnonymousPipeClientStream(PipeDirection.Out, serverHandle);
The full code of the class is pasted below.
Essentially its work like this;
Server Process. Create anonymous pipe set for inbound data - call this Pipe A
Server Process. Starts Client process and passes PipeHandle via command argument
Client Process. Connects to end of Pipe A
Client Process. Create anonymous pipe set for inbound data (Pipe B)
5 Client process. Passes pipe handle back to Server using Pipe A
Server Process. Connects to end of Pipe B
So now we have two anonymous pipes, pointing in opposite directions between Server and Client.
Here is the full code of my IPC class
public class MessageReceivedEventArgs : EventArgs
{
public string Message { get; set; }
}
public class IpcChannel : IDisposable
{
private AnonymousPipeServerStream _inboundPipeServerStream;
private StreamReader _inboundMessageReader;
private string _inboundPipeHandle;
private AnonymousPipeClientStream _outboundPipeServerStream;
private StreamWriter _outboundMessageWriter;
public delegate void MessageReceivedHandler(object sender, MessageReceivedEventArgs e);
public event MessageReceivedHandler MessageReceived;
private Thread _clientListenerThread;
private bool _disposing = false;
public IpcChannel()
{
SetupServerChannel();
}
public IpcChannel(string serverHandle)
{
SetupServerChannel();
// this is the client end of the connection
// create an outbound connection to the server
System.Diagnostics.Trace.TraceInformation("Connecting client stream to server : {0}", serverHandle);
SetupClientChannel(serverHandle);
IntroduceToServer();
}
private void SetupClientChannel(string serverHandle)
{
_outboundPipeServerStream = new AnonymousPipeClientStream(PipeDirection.Out, serverHandle);
_outboundMessageWriter = new StreamWriter(_outboundPipeServerStream)
{
AutoFlush = true
};
}
private void SetupServerChannel()
{
_inboundPipeServerStream = new AnonymousPipeServerStream(PipeDirection.In);
_inboundMessageReader = new StreamReader(_inboundPipeServerStream);
_inboundPipeHandle = _inboundPipeServerStream.GetClientHandleAsString();
_inboundPipeServerStream.DisposeLocalCopyOfClientHandle();
System.Diagnostics.Trace.TraceInformation("Created server stream " + _inboundPipeServerStream.GetClientHandleAsString());
_clientListenerThread = new Thread(ClientListener)
{
IsBackground = true
};
_clientListenerThread.Start();
}
public void SendMessage(string message)
{
System.Diagnostics.Trace.TraceInformation("Sending message {0} chars", message.Length);
_outboundMessageWriter.WriteLine("M" + message);
}
private void IntroduceToServer()
{
System.Diagnostics.Trace.TraceInformation("Telling server callback channel is : " + _inboundPipeServerStream.GetClientHandleAsString());
_outboundMessageWriter.WriteLine("CI" + _inboundPipeServerStream.GetClientHandleAsString());
}
public string ServerHandle
{
get
{
return _inboundPipeHandle;
}
}
private void ProcessControlMessage(string message)
{
if (message.StartsWith("CI"))
{
ConnectResponseChannel(message.Substring(2));
}
}
private void ConnectResponseChannel(string channelHandle)
{
System.Diagnostics.Trace.TraceInformation("Connecting response (OUT) channel to : {0}", channelHandle);
_outboundPipeServerStream = new AnonymousPipeClientStream(PipeDirection.Out, channelHandle);
_outboundMessageWriter = new StreamWriter(_outboundPipeServerStream);
_outboundMessageWriter.AutoFlush = true;
}
private void ClientListener()
{
System.Diagnostics.Trace.TraceInformation("ClientListener started on thread {0}", Thread.CurrentThread.ManagedThreadId);
try
{
while (!_disposing)
{
var message = _inboundMessageReader.ReadLine();
if (message != null)
{
if (message.StartsWith("C"))
{
ProcessControlMessage(message);
}
else if (MessageReceived != null)
MessageReceived(this, new MessageReceivedEventArgs()
{
Message = message.Substring(1)
});
}
}
}
catch (ThreadAbortException)
{
}
finally
{
}
}
public void Dispose()
{
_disposing = true;
_clientListenerThread.Abort();
_outboundMessageWriter.Flush();
_outboundMessageWriter.Close();
_outboundPipeServerStream.Close();
_outboundPipeServerStream.Dispose();
_inboundMessageReader.Close();
_inboundMessageReader.Dispose();
_inboundPipeServerStream.DisposeLocalCopyOfClientHandle();
_inboundPipeServerStream.Close();
_inboundPipeServerStream.Dispose();
}
}
In a single process, it can be used like this;
class Program
{
private static IpcChannel _server;
private static IpcChannel _client;
static void Main(string[] args)
{
_server = new IpcChannel();
_server.MessageReceived += (s, e) => Console.WriteLine("Server Received : " + e.Message);
_client = new IpcChannel(_server.ServerHandle);
_client.MessageReceived += (s, e) => Console.WriteLine("Client Received : " + e.Message);
Console.ReadLine();
_server.SendMessage("This is the server sending to the client");
Console.ReadLine();
_client.SendMessage("This is the client sending to the server");
Console.ReadLine();
_client.Dispose();
_server.Dispose();
}
Thanks in advance for any suggestions.

You didn't post the server code, but anyway. In the server:
You need to specify that the client's pipe handle is inheritable when you create it.
When you launch the client you need to specify that inheritable handles will be inherited.
If you miss either of these steps then the pipe handle will be invalid in the client process.
Also, your step 4 won't work. If you create a pipe handle in the client it won't mean anything to the server when you pass it back. You can make this work using the DuplicateHandle function, but it's much easier to create all the handles in the server and inherit them in the client.
The key point is that handles are per-process, not system-wide.

Starting child process do not forget to set UseShellExecute = false or the handle will not be inherited.

Using WebBrowser control in class library

I'm trying to use this control inside a class library, but when I run the code below, I did not see a request to google being sent (using fiddler).
public class WebBrowserTest
{
public WebBrowserTest()
{
var t = new Thread(StartBrowser);
t.SetApartmentState(ApartmentState.STA);
t.Start();
}
private void StartBrowser()
{
WebBrowser web;
web = new WebBrowser();
web.Navigate("http://www.google.com");
}
}
My guess is this has something to do with threading, and possibly the thread ending before the control gets a chance to send the request. But I have no idea where to start with solving this.
THE SOLUTION
I found this solution to work, the events are getting fired and the main thread waits for the STA thread.
public class WebThread
{
private WebBrowser web { get; set; }
public void StartBrowser()
{
web = new WebBrowser();
web.Visible = true;
web.DocumentCompleted += Web_DocumentCompleted;
web.ScriptErrorsSuppressed = true;
web.Navigate("http://www.google.com");
Application.Run();
web.Dispose();
}
private void Web_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
Debug.Print("Arrived: " + e.Url.ToString());
if (e.Url.ToString() == "http://www.google.com.au/")
{
Application.ExitThread();
}
}
}
public class WebBrowserTest
{
public WebBrowserTest()
{
Debug.Print("Thread is starting.");
var webThread = new WebThread();
var t = new Thread(webThread.StartBrowser);
t.SetApartmentState(ApartmentState.STA);
t.Start();
while(t.IsAlive)
{
Thread.Sleep(5000);
}
Debug.Print("Thread has finished.");
}
}

WebBrowser.Navigate( ... ) doesn't block - it returns immediately, before the request is sent. Since your thread function then exits, your whole thread ends and takes your WebBrowser control with it.
If you're just trying to download a web page, have a look at the WebClient class. It has many async methods which means you probably won't even have to create your own thread.