public void QueueOp(AssetOp op)
{
if (_threadAborted)
{
throw new Exception("Thread has already been aborted for this op manager!");
}
op.SetStatus(OpStatus.Queued);
_opQueue.Enqueue(op);
OpStatusChanged?.Invoke(this, op);
lock (_threadLock)
{
if (_thread != null && !_thread.IsAlive)
{
Log.LogErr("Thread in opmanager was stopped but not null!");
try
{
_thread.Abort();
_opQueue.Where(x => x.Status == OpStatus.Started).ToList().ForEach(x => {
x.SetStatus(OpStatus.Failed, new Exception("Op was in a Started state when the thread died. Failing it."));
Log.LogErr("Op was found in a started state while the thread had died!");
});
_thread = null;
}
catch
{ }
}
if (_thread == null)
{
_thread = new Thread(WorkerThreadProc);
_thread.Start();
}
}
_queueEvent.Set();
}
private void WorkerThreadProc(object o)
{
bool entered = false;
//I *think* this covers all the race conditions where the thread would stop as an item was being enqueued, probably need to re-review
try
{
do
{
if (_threadAborted)
{
Log.LogMsg("Opmanager worker thread has been aborted");
return;
}
AssetOp op = null;
bool dequeued = false;
bool threadAborting = false;
dequeued = _opQueue.TryDequeue(out op);
if (!dequeued)
{
if (entered)
{
Log.LogMsg("trying to exit on thread " + Thread.CurrentThread.ManagedThreadId);
Monitor.Exit(_context.Manager);
entered = false;
}
_queueEvent.WaitOne(2000);
continue;
}
if (!entered)
{
entered = Monitor.TryEnter(_context.Manager);
if (!entered)
{
continue;
}
Log.LogMsg("entered on thread " + Thread.CurrentThread.ManagedThreadId);
}
try
{
Stopwatch sw = new Stopwatch();
op.SetStatus(OpStatus.Started);
OpStatusChanged?.Invoke(this, op);
Log.LogMsg($"AssetOpManager starting op of type {op.GetType().Name}");
sw.Start();
op.PerformOp(_context);
sw.Stop();
Log.LogMsg($"AssetOpManager completed op of type {op.GetType().Name} in {sw.ElapsedMilliseconds}ms");
op.SetStatus(OpStatus.Complete);
OpStatusChanged?.Invoke(this, op);
}
catch (ThreadAbortException)
{
//just die if being aborted
_thread = null;
threadAborting = true;
Log.LogMsg("Op thread aborting");
return;
}
catch (Exception ex)
{
Log.LogErr($"Error handling Op type {op.GetType()}, operation threw an exception.", ex);
op.SetStatus(OpStatus.Failed, ex);
}
finally
{
if (!threadAborting)
{
OpStatusChanged?.Invoke(this, op);
}
}
} while (true);
}
catch (ThreadAbortException)
{
//Thread aborting, so let it
Log.LogErr("Op manager thread is aborting");
_thread = null;
return;
}
catch (Exception ex)
{
Log.LogErr("Exception in op manager's worker thread proc!", ex);
}
finally
{
if (entered)
{
Monitor.Exit(_context.Manager);
}
//just to make sure it gets set null in all cases
_thread = null;
}
}
