Signalling Initialization Failure from Service.OnStart

Question

We have a case where during Service startup (OnStart), a worker thread is started. The worker thread connects to a SQL database. If the database is unavailable, the worker thread can signal the main thread of the failure. The question is; How to signal the Service Control Manager that startup has failed.

Answer 1

This is how we handled this situation. This code was added to our main service class and then at the point where we wanted to return startup as failed, made a call to SetServiceFail(1065) followed by a return from OnStart. In this case 1065 returns a database does not exist status.

I would also note that in SetServiceFail I hard-coded the serviceType since in our case all of our services are stand-alone so I kept it simple.

private void SetServiceFail (int ErrorCode)
{
     SERVICE_STATUS _ServiceStatus = new SERVICE_STATUS ();
     _ServiceStatus.currentState = (int) State.SERVICE_STOPPED;
     _ServiceStatus.serviceType = 16; //SERVICE_WIN32_OWN_PROCESS
     _ServiceStatus.waitHint = 0;
     _ServiceStatus.win32ExitCode = ErrorCode;
     _ServiceStatus.serviceSpecificExitCode = 0;
     _ServiceStatus.checkPoint = 0;
     _ServiceStatus.controlsAccepted = 0 |
           (this.CanStop ? (int) ControlsAccepted.ACCEPT_STOP : 0) |
           (this.CanShutdown ? (int) ControlsAccepted.ACCEPT_SHUTDOWN : 0) |
           (this.CanPauseAndContinue ? (int) ControlsAccepted.ACCEPT_PAUSE_CONTINUE : 0) |
           (this.CanHandleSessionChangeEvent ? (int) ControlsAccepted.ACCEPT_SESSION_CHANGE : 0) |
           (this.CanHandlePowerEvent ? (int) ControlsAccepted.ACCEPT_POWER_EVENT : 0);
     SetServiceStatus (this.ServiceHandle, ref _ServiceStatus);
}

public enum State
{
     SERVICE_STOPPED = 1,
     SERVICE_START_PENDING = 2,
     SERVICE_STOP_PENDING = 3,
     SERVICE_RUNNING = 4,
     SERVICE_CONTINUE_PENDING = 5,
     SERVICE_PAUSE_PENDING = 6,
     SERVICE_PAUSED = 7
}

public enum ControlsAccepted
{
     ACCEPT_STOP = 1,
     ACCEPT_PAUSE_CONTINUE = 2,
     ACCEPT_SHUTDOWN = 4,
     ACCEPT_POWER_EVENT = 64,
     ACCEPT_SESSION_CHANGE = 128
}

[StructLayout (LayoutKind.Sequential)]
private struct SERVICE_STATUS
{
     public int serviceType;
     public int currentState;
     public int controlsAccepted;
     public int win32ExitCode;
     public int serviceSpecificExitCode;
     public int checkPoint;
     public int waitHint;
}

[DllImport ("advapi32.dll")]
private static extern bool SetServiceStatus (IntPtr hServiceStatus, ref SERVICE_STATUS lpServiceStatus);

Answer 2

One way to stop it is to use the ServiceController, but you wont get any fancy message in the service control manager about an error or a failure to start.

var controller = new System.ServiceProcess.ServiceController("NameOfYourService");
controller.Stop();