private static async Task ListenCoreAsync(
string pipeName,
AsyncQueue <ListenResult> queue,
Func <string> getClientLoggingIdentifier,
CancellationToken cancellationToken)
{
while (!cancellationToken.IsCancellationRequested)
{
NamedPipeServerStream?pipeStream = null;
try
{
// Create the pipe and begin waiting for a connection. This
// doesn't block, but could fail in certain circumstances, such
// as Windows refusing to create the pipe for some reason
// (out of handles?), or the pipe was disconnected before we
// starting listening
CompilerServerLogger.Log($"Constructing pipe and waiting for connections '{pipeName}'");
pipeStream = NamedPipeUtil.CreateServer(pipeName);
// The WaitForConnectionAsync API does not fully respect the provided CancellationToken
// on all platforms:
//
// https://github.com/dotnet/runtime/issues/40289
//
// To mitigate this we need to setup a cancellation Task and dispose the NamedPipeServerStream
// if it ever completes. Once all of the NamedPipeServerStream for the given pipe name are
// disposed they will all exit the WaitForConnectionAsync method
var connectTask = pipeStream.WaitForConnectionAsync(cancellationToken);
if (!PlatformInformation.IsWindows)
{
var cancelTask = Task.Delay(TimeSpan.FromMilliseconds(-1), cancellationToken);
var completedTask = await Task.WhenAny(new[] { connectTask, cancelTask }).ConfigureAwait(false);
if (completedTask == cancelTask)
{
throw new OperationCanceledException();
}
}
await connectTask.ConfigureAwait(false);
CompilerServerLogger.Log("Pipe connection established.");
var connection = new NamedPipeClientConnection(pipeStream, getClientLoggingIdentifier());
queue.Enqueue(new ListenResult(connection: connection));
}
catch (OperationCanceledException)
{
// Expected when the host is shutting down.
CompilerServerLogger.Log($"Pipe connection cancelled");
pipeStream?.Dispose();
}
catch (Exception ex)
{
CompilerServerLogger.LogException(ex, $"Pipe connection error");
queue.Enqueue(new ListenResult(exception: ex));
pipeStream?.Dispose();
}
}
}
/// <summary>
/// Creates a Task representing the processing of the new connection. Returns null
/// if the server is unable to create a new Task object for the connection.
/// </summary>
private async Task <CompletionReason> CreateHandleConnectionTask(Task <NamedPipeServerStream> pipeStreamTask, TaskCompletionSource <TimeSpan?> changeKeepAliveSource, CancellationToken cancellationToken)
{
var pipeStream = await pipeStreamTask.ConfigureAwait(false);
var clientConnection = new NamedPipeClientConnection(pipeStream);
var connection = new Connection(clientConnection, _handler);
return(await connection.ServeConnection(changeKeepAliveSource, cancellationToken).ConfigureAwait(false));
}
/// <summary>
/// Creates a Task representing the processing of the new connection. This will return a task that
/// will never fail. It will always produce a <see cref="ConnectionData"/> value. Connection errors
/// will end up being represented as <see cref="CompletionReason.ClientDisconnect"/>
/// </summary>
internal static async Task <ConnectionData> CreateHandleConnectionTask(Task <NamedPipeServerStream> pipeStreamTask, IRequestHandler handler, CancellationToken cancellationToken)
{
Connection connection;
try
{
var pipeStream = await pipeStreamTask.ConfigureAwait(false);
var clientConnection = new NamedPipeClientConnection(pipeStream);
connection = new Connection(clientConnection, handler);
}
catch (Exception ex)
{
// Unable to establish a connection with the client. The client is responsible for
// handling this case. Nothing else for us to do here.
CompilerServerLogger.LogException(ex, "Error creating client named pipe");
return(new ConnectionData(CompletionReason.CompilationNotStarted));
}
return(await connection.ServeConnection(cancellationToken).ConfigureAwait(false));
}
/// <summary>
/// Creates a Task representing the processing of the new connection. This will return a task that
/// will never fail. It will always produce a <see cref="ConnectionData"/> value. Connection errors
/// will end up being represented as <see cref="CompletionReason.ClientDisconnect"/>
/// </summary>
internal static async Task<ConnectionData> CreateHandleConnectionTask(Task<NamedPipeServerStream> pipeStreamTask, IRequestHandler handler, CancellationToken cancellationToken)
{
Connection connection;
try
{
var pipeStream = await pipeStreamTask.ConfigureAwait(false);
var clientConnection = new NamedPipeClientConnection(pipeStream);
connection = new Connection(clientConnection, handler);
}
catch (Exception ex)
{
// Unable to establish a connection with the client. The client is responsible for
// handling this case. Nothing else for us to do here.
CompilerServerLogger.LogException(ex, "Error creating client named pipe");
return new ConnectionData(CompletionReason.CompilationNotStarted);
}
return await connection.ServeConnection(cancellationToken).ConfigureAwait(false);
}
/// <summary>
/// Creates a Task representing the processing of the new connection. Returns null
/// if the server is unable to create a new Task object for the connection.
/// </summary>
private async Task<CompletionReason> CreateHandleConnectionTask(Task<NamedPipeServerStream> pipeStreamTask, TaskCompletionSource<TimeSpan?> changeKeepAliveSource, CancellationToken cancellationToken)
{
var pipeStream = await pipeStreamTask.ConfigureAwait(false);
var clientConnection = new NamedPipeClientConnection(pipeStream);
var connection = new Connection(clientConnection, _handler);
return await connection.ServeConnection(changeKeepAliveSource, cancellationToken).ConfigureAwait(false);
}