/// <summary>
/// Perform necessary actions to shut down the node.
/// </summary>
private NodeEngineShutdownReason HandleShutdown()
{
// Wait for the RunTask task runner thread before shutting down so that we can cleanly dispose all WaitHandles.
if (_taskRunnerThread != null)
{
_taskRunnerThread.Join();
}
if (_debugCommunications)
{
using (StreamWriter writer = File.CreateText(String.Format(CultureInfo.CurrentCulture, Path.Combine(Path.GetTempPath(), @"MSBuild_NodeShutdown_{0}.txt"), Process.GetCurrentProcess().Id)))
{
writer.WriteLine("Node shutting down with reason {0}.", _shutdownReason);
}
}
#if !CLR2COMPATIBILITY
_registeredTaskObjectCache.DisposeCacheObjects(RegisteredTaskObjectLifetime.Build);
_registeredTaskObjectCache = null;
#endif
// Restore the original current directory.
NativeMethodsShared.SetCurrentDirectory(Environment.SystemDirectory);
// Restore the original environment.
CommunicationsUtilities.SetEnvironment(_savedEnvironment);
if (_nodeEndpoint.LinkStatus == LinkStatus.Active)
{
// Notify the BuildManager that we are done.
_nodeEndpoint.SendData(new NodeShutdown(_shutdownReason == NodeEngineShutdownReason.Error ? NodeShutdownReason.Error : NodeShutdownReason.Requested));
// Flush all packets to the pipe and close it down. This blocks until the shutdown is complete.
_nodeEndpoint.OnLinkStatusChanged -= new LinkStatusChangedDelegate(OnLinkStatusChanged);
}
_nodeEndpoint.Disconnect();
// Dispose these WaitHandles
_packetReceivedEvent.Close();
_shutdownEvent.Close();
_taskCompleteEvent.Close();
_taskCancelledEvent.Close();
return _shutdownReason;
}
/// <summary>
/// Starts up the node and processes messages until the node is requested to shut down.
/// </summary>
/// <param name="shutdownException">The exception which caused shutdown, if any.</param>
/// <returns>The reason for shutting down.</returns>
public NodeEngineShutdownReason Run(out Exception shutdownException)
{
#if !CLR2COMPATIBILITY
_registeredTaskObjectCache = new RegisteredTaskObjectCacheBase();
#endif
shutdownException = null;
// Snapshot the current environment
_savedEnvironment = CommunicationsUtilities.GetEnvironmentVariables();
string pipeName = "MSBuild" + Process.GetCurrentProcess().Id;
_nodeEndpoint = new NodeEndpointOutOfProcTaskHost(pipeName);
_nodeEndpoint.OnLinkStatusChanged += new LinkStatusChangedDelegate(OnLinkStatusChanged);
_nodeEndpoint.Listen(this);
WaitHandle[] waitHandles = new WaitHandle[] { _shutdownEvent, _packetReceivedEvent, _taskCompleteEvent, _taskCancelledEvent };
while (true)
{
int index = WaitHandle.WaitAny(waitHandles);
switch (index)
{
case 0: // shutdownEvent
NodeEngineShutdownReason shutdownReason = HandleShutdown();
return shutdownReason;
case 1: // packetReceivedEvent
INodePacket packet = null;
int packetCount = _receivedPackets.Count;
while (packetCount > 0)
{
lock (_receivedPackets)
{
if (_receivedPackets.Count > 0)
{
packet = _receivedPackets.Dequeue();
}
else
{
break;
}
}
if (packet != null)
{
HandlePacket(packet);
}
}
break;
case 2: // taskCompleteEvent
CompleteTask();
break;
case 3: // taskCancelledEvent
CancelTask();
break;
}
}
// UNREACHABLE
}
