/// <summary>
/// Listens at the transport path for new connections.
/// </summary>
/// <param name="maxConnections">The maximum number of connections the server will support.</param>
/// <param name="token">The token to monitor for cancellation requests.</param>
/// <returns>A task that completes when the server is no longer listening at the transport path.</returns>
private async Task ListenAsync(int maxConnections, CancellationToken token)
{
using var transport = IpcServerTransport.Create(_transportPath, maxConnections);
while (!token.IsCancellationRequested)
{
Stream stream = null;
IpcAdvertise advertise = null;
try
{
stream = await transport.AcceptAsync(token).ConfigureAwait(false);
}
catch (OperationCanceledException)
{
}
catch (Exception)
{
// The advertise data could be incomplete if the runtime shuts down before completely writing
// the information. Catch the exception and continue waiting for a new connection.
}
if (null != stream)
{
// Cancel parsing of advertise data after timeout period to
// mitigate runtimes that write partial data and do not close the stream (avoid waiting forever).
using var parseCancellationSource = new CancellationTokenSource();
using var linkedSource = CancellationTokenSource.CreateLinkedTokenSource(token, parseCancellationSource.Token);
try
{
parseCancellationSource.CancelAfter(ParseAdvertiseTimeout);
advertise = await IpcAdvertise.ParseAsync(stream, linkedSource.Token).ConfigureAwait(false);
}
catch (Exception)
{
}
}
if (null != advertise)
{
Guid runtimeCookie = advertise.RuntimeInstanceCookie;
int pid = unchecked ((int)advertise.ProcessId);
lock (_streamLock)
{
ProvideStream(runtimeCookie, stream);
if (!_cachedEndpoints.ContainsKey(runtimeCookie))
{
ServerIpcEndpoint endpoint = new ServerIpcEndpoint(this, runtimeCookie);
_cachedEndpoints.Add(runtimeCookie, endpoint);
ProvideEndpointInfo(new IpcEndpointInfo(endpoint, pid, runtimeCookie));
}
}
}
}
}
public bool Equals(ServerIpcEndpoint other)
{
return(other != null && other._runtimeId == _runtimeId && other._server == _server);
}
/// <summary>
/// Listens at the address for new connections.
/// </summary>
/// <param name="maxConnections">The maximum number of connections the server will support.</param>
/// <param name="token">The token to monitor for cancellation requests.</param>
/// <returns>A task that completes when the server is no longer listening at the address.</returns>
private async Task ListenAsync(int maxConnections, CancellationToken token)
{
// This disposal shuts down the transport in case an exception is thrown.
using var transport = IpcServerTransport.Create(_address, maxConnections, _enableTcpIpProtocol, TransportCallback);
// This disposal shuts down the transport in case of cancellation; causes the transport
// to not recreate the server stream before the AcceptAsync call observes the cancellation.
using var _ = token.Register(() => transport.Dispose());
while (!token.IsCancellationRequested)
{
Stream stream = null;
IpcAdvertise advertise = null;
try
{
stream = await transport.AcceptAsync(token).ConfigureAwait(false);
}
catch (OperationCanceledException)
{
}
catch (Exception)
{
// The advertise data could be incomplete if the runtime shuts down before completely writing
// the information. Catch the exception and continue waiting for a new connection.
}
if (null != stream)
{
// Cancel parsing of advertise data after timeout period to
// mitigate runtimes that write partial data and do not close the stream (avoid waiting forever).
using var parseCancellationSource = new CancellationTokenSource();
using var linkedSource = CancellationTokenSource.CreateLinkedTokenSource(token, parseCancellationSource.Token);
try
{
parseCancellationSource.CancelAfter(ParseAdvertiseTimeout);
advertise = await IpcAdvertise.ParseAsync(stream, linkedSource.Token).ConfigureAwait(false);
}
catch (Exception)
{
stream.Dispose();
}
}
if (null != advertise)
{
Guid runtimeCookie = advertise.RuntimeInstanceCookie;
int pid = unchecked ((int)advertise.ProcessId);
// The valueFactory parameter of the GetOrAdd overload that uses Func<TKey, TValue> valueFactory
// does not execute the factory under a lock thus it is not thread-safe. Create the collection and
// use a thread-safe version of GetOrAdd; use equality comparison on the result to determine if
// the new collection was added to the dictionary or if an existing one was returned.
var newStreamCollection = new HandleableCollection <Stream>();
var streamCollection = _streamCollections.GetOrAdd(runtimeCookie, newStreamCollection);
try
{
streamCollection.ClearItems();
streamCollection.Add(stream);
if (newStreamCollection == streamCollection)
{
ServerIpcEndpoint endpoint = new ServerIpcEndpoint(this, runtimeCookie);
_endpointInfos.Add(new IpcEndpointInfo(endpoint, pid, runtimeCookie));
}
else
{
newStreamCollection.Dispose();
}
}
catch (ObjectDisposedException)
{
// The stream collection could be disposed by RemoveConnection which would cause an
// ObjectDisposedException to be thrown if trying to clear/add the stream.
stream.Dispose();
}
}
}
}
/// <summary>
/// Provides endpoint information when a new runtime instance connects to the server.
/// </summary>
/// <param name="token">The token to monitor for cancellation requests.</param>
/// <returns>A <see cref="IpcEndpointInfo"/> that contains information about the new runtime instance connection.</returns>
/// <remarks>
/// This will only provide endpoint information on the first time a runtime connects to the server.
/// If a connection is removed using <see cref="RemoveConnection(Guid)"/> and the same runtime instance,
/// reconnects after this call, then a new <see cref="IpcEndpointInfo"/> will be produced.
/// </remarks>
public async Task <IpcEndpointInfo> AcceptAsync(CancellationToken token)
{
VerifyNotDisposed();
while (true)
{
Stream stream = null;
IpcAdvertise advertise = null;
try
{
stream = await _transport.AcceptAsync(token).ConfigureAwait(false);
}
catch (Exception ex) when(!(ex is OperationCanceledException))
{
// The advertise data could be incomplete if the runtime shuts down before completely writing
// the information. Catch the exception and continue waiting for a new connection.
}
token.ThrowIfCancellationRequested();
if (null != stream)
{
// Cancel parsing of advertise data after timeout period to
// mitigate runtimes that write partial data and do not close the stream (avoid waiting forever).
using var parseCancellationSource = new CancellationTokenSource();
using var linkedSource = CancellationTokenSource.CreateLinkedTokenSource(token, parseCancellationSource.Token);
try
{
parseCancellationSource.CancelAfter(ParseAdvertiseTimeout);
advertise = await IpcAdvertise.ParseAsync(stream, linkedSource.Token).ConfigureAwait(false);
}
catch (OperationCanceledException) when(parseCancellationSource.IsCancellationRequested)
{
// Only handle cancellation if it was due to the parse timeout.
}
catch (Exception ex) when(!(ex is OperationCanceledException))
{
// Catch all other exceptions and continue waiting for a new connection.
}
}
token.ThrowIfCancellationRequested();
if (null != advertise)
{
Guid runtimeCookie = advertise.RuntimeInstanceCookie;
int pid = unchecked ((int)advertise.ProcessId);
lock (_lock)
{
ProvideStream(runtimeCookie, stream);
// Consumers should hold onto the endpoint info and use it for diagnostic communication,
// regardless of the number of times the same runtime instance connects. This requires consumers
// to continuously invoke the AcceptAsync method in order to handle runtime instance reconnects,
// even if the consumer only wants to handle a single endpoint.
if (!_cachedEndpoints.ContainsKey(runtimeCookie))
{
ServerIpcEndpoint endpoint = new ServerIpcEndpoint(this, runtimeCookie);
_cachedEndpoints.Add(runtimeCookie, endpoint);
return(new IpcEndpointInfo(endpoint, pid, runtimeCookie));
}
}
}
token.ThrowIfCancellationRequested();
}
}
