public async Task WriteAsync(Stream outStream, CancellationToken cancellationToken)
{
using (var memoryStream = new MemoryStream())
using (var writer = new BinaryWriter(memoryStream, Encoding.Unicode))
{
// Format the response
ServerLogger.Log("Formatting Response");
writer.Write((int)Type);
AddResponseBody(writer);
writer.Flush();
cancellationToken.ThrowIfCancellationRequested();
// Send the response to the client
// Write the length of the response
var length = checked ((int)memoryStream.Length);
ServerLogger.Log("Writing response length");
// There is no way to know the number of bytes written to
// the pipe stream. We just have to assume all of them are written.
await outStream
.WriteAsync(BitConverter.GetBytes(length), 0, 4, cancellationToken)
.ConfigureAwait(false);
// Write the response
ServerLogger.Log("Writing response of size {0}", length);
memoryStream.Position = 0;
await memoryStream
.CopyToAsync(outStream, bufferSize : length, cancellationToken : cancellationToken)
.ConfigureAwait(false);
}
}
public async override Task WaitForDisconnectAsync(CancellationToken cancellationToken)
{
if (!(Stream is PipeStream pipeStream))
{
return;
}
// We have to poll for disconnection by reading, PipeStream.IsConnected isn't reliable unless you
// actually do a read - which will cause it to update its state.
while (!cancellationToken.IsCancellationRequested && pipeStream.IsConnected)
{
await Task.Delay(TimeSpan.FromMilliseconds(100), cancellationToken);
try
{
ServerLogger.Log($"Before poking pipe {Identifier}.");
await Stream.ReadAsync(Array.Empty <byte>(), 0, 0, cancellationToken);
ServerLogger.Log($"After poking pipe {Identifier}.");
}
catch (OperationCanceledException)
{
}
catch (Exception e)
{
// It is okay for this call to fail. Errors will be reflected in the
// IsConnected property which will be read on the next iteration.
ServerLogger.LogException(e, $"Error poking pipe {Identifier}.");
}
}
}
public async override Task <Connection> WaitForConnectionAsync(CancellationToken cancellationToken)
{
// Create the pipe and begin waiting for a connection. This doesn't block, but could fail
// in certain circumstances, such as the OS refusing to create the pipe for some reason
// or the pipe was disconnected before we starting listening.
var pipeStream = new NamedPipeServerStream(
PipeName,
PipeDirection.InOut,
NamedPipeServerStream.MaxAllowedServerInstances, // Maximum connections.
PipeTransmissionMode.Byte,
_pipeOptions,
PipeBufferSize, // Default input buffer
PipeBufferSize); // Default output buffer
ServerLogger.Log("Waiting for new connection");
await pipeStream.WaitForConnectionAsync(cancellationToken);
ServerLogger.Log("Pipe connection detected.");
if (Environment.Is64BitProcess || Memory.IsMemoryAvailable())
{
ServerLogger.Log("Memory available - accepting connection");
return(new NamedPipeConnection(pipeStream, GetNextIdentifier()));
}
pipeStream.Close();
throw new Exception("Insufficient resources to process new connection.");
}
/// <summary>
/// This task does not complete until we are completely done reading.
/// </summary>
internal static async Task ReadAllAsync(
Stream stream,
byte[] buffer,
int count,
CancellationToken cancellationToken)
{
var totalBytesRead = 0;
do
{
ServerLogger.Log("Attempting to read {0} bytes from the stream", count - totalBytesRead);
var bytesRead = await stream.ReadAsync(
buffer,
totalBytesRead,
count - totalBytesRead,
cancellationToken)
.ConfigureAwait(false);
if (bytesRead == 0)
{
ServerLogger.Log("Unexpected -- read 0 bytes from the stream.");
throw new EndOfStreamException("Reached end of stream before end of read.");
}
ServerLogger.Log("Read {0} bytes", bytesRead);
totalBytesRead += bytesRead;
} while (totalBytesRead < count);
ServerLogger.Log("Finished read");
}
public static ServerRequest Create(
string workingDirectory,
string tempDirectory,
IList <string> args,
string keepAlive = null)
{
ServerLogger.Log("Creating ServerRequest");
ServerLogger.Log($"Working directory: {workingDirectory}");
ServerLogger.Log($"Temp directory: {tempDirectory}");
var requestLength = args.Count + 1;
var requestArgs = new List <RequestArgument>(requestLength)
{
new RequestArgument(RequestArgument.ArgumentId.CurrentDirectory, 0, workingDirectory),
new RequestArgument(RequestArgument.ArgumentId.TempDirectory, 0, tempDirectory)
};
if (keepAlive != null)
{
requestArgs.Add(new RequestArgument(RequestArgument.ArgumentId.KeepAlive, 0, keepAlive));
}
for (var i = 0; i < args.Count; ++i)
{
var arg = args[i];
ServerLogger.Log($"argument[{i}] = {arg}");
requestArgs.Add(new RequestArgument(RequestArgument.ArgumentId.CommandLineArgument, i, arg));
}
return(new ServerRequest(ServerProtocol.ProtocolVersion, requestArgs));
}
public override ServerResponse Execute(ServerRequest request, CancellationToken cancellationToken)
{
if (!TryParseArguments(request, out var parsed))
{
return(new RejectedServerResponse());
}
var exitCode = 0;
var commandArgs = parsed.args.ToArray();
var outputWriter = new StringWriter();
var errorWriter = new StringWriter();
var checker = new DefaultExtensionDependencyChecker(Loader, outputWriter, errorWriter);
var app = new Application(cancellationToken, Loader, checker, AssemblyReferenceProvider, outputWriter, errorWriter);
exitCode = app.Execute(commandArgs);
var output = outputWriter.ToString();
var error = errorWriter.ToString();
outputWriter.Dispose();
errorWriter.Dispose();
// This will no-op if server logging is not enabled.
ServerLogger.Log(output);
ServerLogger.Log(error);
return(new CompletedServerResponse(exitCode, utf8output: false, output, error));
}
/// <summary>
/// Try to process the request using the server. Returns a null-containing Task if a response
/// from the server cannot be retrieved.
/// </summary>
private static async Task <ServerResponse> TryProcessRequest(
Client client,
ServerRequest request,
CancellationToken cancellationToken)
{
ServerResponse response;
using (client)
{
// Write the request
try
{
ServerLogger.Log("Begin writing request");
await request.WriteAsync(client.Stream, cancellationToken).ConfigureAwait(false);
ServerLogger.Log("End writing request");
}
catch (Exception e)
{
ServerLogger.LogException(e, "Error writing build request.");
return(new RejectedServerResponse());
}
// Wait for the compilation and a monitor to detect if the server disconnects
var serverCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
ServerLogger.Log("Begin reading response");
var responseTask = ServerResponse.ReadAsync(client.Stream, serverCts.Token);
var monitorTask = client.WaitForDisconnectAsync(serverCts.Token);
await Task.WhenAny(new[] { responseTask, monitorTask }).ConfigureAwait(false);
ServerLogger.Log("End reading response");
if (responseTask.IsCompleted)
{
// await the task to log any exceptions
try
{
response = await responseTask.ConfigureAwait(false);
}
catch (Exception e)
{
ServerLogger.LogException(e, "Error reading response");
response = new RejectedServerResponse();
}
}
else
{
ServerLogger.Log("Server disconnect");
response = new RejectedServerResponse();
}
// Cancel whatever task is still around
serverCts.Cancel();
Debug.Assert(response != null);
return(response);
}
}
// Based on: https://github.com/dotnet/roslyn/blob/14aed138a01c448143b9acf0fe77a662e3dfe2f4/src/Compilers/Shared/BuildServerConnection.cs#L290
public static async Task <Client> ConnectAsync(string pipeName, TimeSpan?timeout, CancellationToken cancellationToken)
{
var timeoutMilliseconds = timeout == null ? Timeout.Infinite : (int)timeout.Value.TotalMilliseconds;
try
{
// Machine-local named pipes are named "\\.\pipe\<pipename>".
// We use the SHA1 of the directory the compiler exes live in as the pipe name.
// The NamedPipeClientStream class handles the "\\.\pipe\" part for us.
ServerLogger.Log("Attempt to open named pipe '{0}'", pipeName);
var stream = new NamedPipeClientStream(".", pipeName, PipeDirection.InOut, _pipeOptions);
cancellationToken.ThrowIfCancellationRequested();
ServerLogger.Log("Attempt to connect named pipe '{0}'", pipeName);
try
{
await stream.ConnectAsync(timeoutMilliseconds, cancellationToken);
}
catch (Exception e) when(e is IOException || e is TimeoutException)
{
// Note: IOException can also indicate timeout.
// From docs:
// - TimeoutException: Could not connect to the server within the specified timeout period.
// - IOException: The server is connected to another client and the time-out period has expired.
ServerLogger.Log($"Connecting to server timed out after {timeoutMilliseconds} ms");
return(null);
}
ServerLogger.Log("Named pipe '{0}' connected", pipeName);
cancellationToken.ThrowIfCancellationRequested();
#if NETFRAMEWORK
// Verify that we own the pipe.
if (!CheckPipeConnectionOwnership(stream))
{
ServerLogger.Log("Owner of named pipe is incorrect");
return(null);
}
#endif
return(new NamedPipeClient(stream, GetNextIdentifier()));
}
catch (Exception e) when(!(e is TaskCanceledException || e is OperationCanceledException))
{
ServerLogger.LogException(e, "Exception while connecting to process");
return(null);
}
}
private Task <ServerResponse> ExecuteRequestAsync(ServerRequest buildRequest, CancellationToken cancellationToken)
{
Func <ServerResponse> func = () =>
{
ServerLogger.Log("Begin processing request");
var response = _compilerHost.Execute(buildRequest, cancellationToken);
ServerLogger.Log("End processing request");
return(response);
};
var task = new Task <ServerResponse>(func, cancellationToken, TaskCreationOptions.LongRunning);
task.Start();
return(task);
}
protected override void Dispose(bool disposing)
{
ServerLogger.Log($"Pipe {Identifier}: Closing.");
try
{
Stream.Dispose();
}
catch (Exception ex)
{
// The client connection failing to close isn't fatal to the server process. It is simply a client
// for which we can no longer communicate and that's okay because the Close method indicates we are
// done with the client already.
var message = $"Pipe {Identifier}: Error closing pipe.";
ServerLogger.LogException(ex, message);
}
}
/// <summary>
/// Read a Request from the given stream.
///
/// The total request size must be less than 1MB.
/// </summary>
/// <returns>null if the Request was too large, the Request otherwise.</returns>
public static async Task <ServerRequest> ReadAsync(Stream inStream, CancellationToken cancellationToken)
{
// Read the length of the request
var lengthBuffer = new byte[4];
ServerLogger.Log("Reading length of request");
await ServerProtocol.ReadAllAsync(inStream, lengthBuffer, 4, cancellationToken).ConfigureAwait(false);
var length = BitConverter.ToInt32(lengthBuffer, 0);
// Back out if the request is > 1MB
if (length > 0x100000)
{
ServerLogger.Log("Request is over 1MB in length, cancelling read.");
return(null);
}
cancellationToken.ThrowIfCancellationRequested();
// Read the full request
var requestBuffer = new byte[length];
await ServerProtocol.ReadAllAsync(inStream, requestBuffer, length, cancellationToken).ConfigureAwait(false);
cancellationToken.ThrowIfCancellationRequested();
ServerLogger.Log("Parsing request");
// Parse the request into the Request data structure.
using (var reader = new BinaryReader(new MemoryStream(requestBuffer), Encoding.Unicode))
{
var protocolVersion = reader.ReadUInt32();
var argumentCount = reader.ReadUInt32();
var argumentsBuilder = new List <RequestArgument>((int)argumentCount);
for (var i = 0; i < argumentCount; i++)
{
cancellationToken.ThrowIfCancellationRequested();
argumentsBuilder.Add(RequestArgument.ReadFromBinaryReader(reader));
}
return(new ServerRequest(protocolVersion, argumentsBuilder));
}
}
/// <summary>
/// May throw exceptions if there are pipe problems.
/// </summary>
/// <param name="stream"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
public static async Task <ServerResponse> ReadAsync(Stream stream, CancellationToken cancellationToken = default(CancellationToken))
{
ServerLogger.Log("Reading response length");
// Read the response length
var lengthBuffer = new byte[4];
await ServerProtocol.ReadAllAsync(stream, lengthBuffer, 4, cancellationToken).ConfigureAwait(false);
var length = BitConverter.ToUInt32(lengthBuffer, 0);
// Read the response
ServerLogger.Log("Reading response of length {0}", length);
var responseBuffer = new byte[length];
await ServerProtocol.ReadAllAsync(
stream,
responseBuffer,
responseBuffer.Length,
cancellationToken)
.ConfigureAwait(false);
using (var reader = new BinaryReader(new MemoryStream(responseBuffer), Encoding.Unicode))
{
var responseType = (ResponseType)reader.ReadInt32();
switch (responseType)
{
case ResponseType.Completed:
return(CompletedServerResponse.Create(reader));
case ResponseType.MismatchedVersion:
return(new MismatchedVersionServerResponse());
case ResponseType.Shutdown:
return(ShutdownServerResponse.Create(reader));
case ResponseType.Rejected:
return(new RejectedServerResponse());
default:
throw new InvalidOperationException("Received invalid response type from server.");
}
}
}
/// <summary>
/// Write a Request to the stream.
/// </summary>
public async Task WriteAsync(Stream outStream, CancellationToken cancellationToken = default(CancellationToken))
{
using (var memoryStream = new MemoryStream())
using (var writer = new BinaryWriter(memoryStream, Encoding.Unicode))
{
// Format the request.
ServerLogger.Log("Formatting request");
writer.Write(ProtocolVersion);
writer.Write(Arguments.Count);
foreach (var arg in Arguments)
{
cancellationToken.ThrowIfCancellationRequested();
arg.WriteToBinaryWriter(writer);
}
writer.Flush();
cancellationToken.ThrowIfCancellationRequested();
// Write the length of the request
var length = checked ((int)memoryStream.Length);
// Back out if the request is > 1 MB
if (memoryStream.Length > 0x100000)
{
ServerLogger.Log("Request is over 1MB in length, cancelling write");
throw new ArgumentOutOfRangeException();
}
// Send the request to the server
ServerLogger.Log("Writing length of request.");
await outStream
.WriteAsync(BitConverter.GetBytes(length), 0, 4, cancellationToken)
.ConfigureAwait(false);
ServerLogger.Log("Writing request of size {0}", length);
// Write the request
memoryStream.Position = 0;
await memoryStream
.CopyToAsync(outStream, bufferSize : length, cancellationToken : cancellationToken)
.ConfigureAwait(false);
}
}
private static int RunApplication(string[] args)
{
DebugMode.HandleDebugSwitch(ref args);
var cancel = new CancellationTokenSource();
Console.CancelKeyPress += (sender, e) => { cancel.Cancel(); };
var outputWriter = new StringWriter();
var errorWriter = new StringWriter();
// Prevent shadow copying.
var loader = new DefaultExtensionAssemblyLoader(baseDirectory: null);
var checker = new DefaultExtensionDependencyChecker(loader, outputWriter, errorWriter);
var application = new Application(
cancel.Token,
loader,
checker,
(path, properties) => MetadataReference.CreateFromFile(path, properties),
outputWriter,
errorWriter);
var result = application.Execute(args);
var output = outputWriter.ToString();
var error = errorWriter.ToString();
outputWriter.Dispose();
errorWriter.Dispose();
Console.Write(output);
Console.Error.Write(error);
// This will no-op if server logging is not enabled.
ServerLogger.Log(output);
ServerLogger.Log(error);
return(result);
}
internal async Task <ConnectionResult> AcceptConnection(Task <Connection> task, bool accept, CancellationToken cancellationToken)
{
Connection connection;
try
{
connection = await task;
}
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.
ServerLogger.LogException(ex, "Error creating client named pipe");
return(new ConnectionResult(ConnectionResult.Reason.CompilationNotStarted));
}
try
{
using (connection)
{
ServerRequest request;
try
{
ServerLogger.Log("Begin reading request.");
request = await ServerRequest.ReadAsync(connection.Stream, cancellationToken).ConfigureAwait(false);
ServerLogger.Log("End reading request.");
}
catch (Exception e)
{
ServerLogger.LogException(e, "Error reading build request.");
return(new ConnectionResult(ConnectionResult.Reason.CompilationNotStarted));
}
if (request.IsShutdownRequest())
{
// Reply with the PID of this process so that the client can wait for it to exit.
var response = new ShutdownServerResponse(Environment.ProcessId);
await response.WriteAsync(connection.Stream, cancellationToken);
// We can safely disconnect the client, then when this connection gets cleaned up by the event loop
// the server will go to a shutdown state.
return(new ConnectionResult(ConnectionResult.Reason.ClientShutdownRequest));
}
else if (!accept)
{
// We're already in shutdown mode, respond gracefully so the client can run in-process.
var response = new RejectedServerResponse();
await response.WriteAsync(connection.Stream, cancellationToken).ConfigureAwait(false);
return(new ConnectionResult(ConnectionResult.Reason.CompilationNotStarted));
}
else
{
// If we get here then this is a real request that we will accept and process.
//
// Kick off both the compilation and a task to monitor the pipe for closing.
var buildCancelled = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
var watcher = connection.WaitForDisconnectAsync(buildCancelled.Token);
var worker = ExecuteRequestAsync(request, buildCancelled.Token);
// await will end when either the work is complete or the connection is closed.
await Task.WhenAny(worker, watcher);
// Do an 'await' on the completed task, preference being compilation, to force
// any exceptions to be realized in this method for logging.
ConnectionResult.Reason reason;
if (worker.IsCompleted)
{
var response = await worker;
try
{
ServerLogger.Log("Begin writing response.");
await response.WriteAsync(connection.Stream, cancellationToken);
ServerLogger.Log("End writing response.");
reason = ConnectionResult.Reason.CompilationCompleted;
_eventBus.CompilationCompleted();
}
catch
{
reason = ConnectionResult.Reason.ClientDisconnect;
}
}
else
{
await watcher;
reason = ConnectionResult.Reason.ClientDisconnect;
}
// Begin the tear down of the Task which didn't complete.
buildCancelled.Cancel();
return(new ConnectionResult(reason, request.KeepAlive));
}
}
}
catch (Exception ex)
{
ServerLogger.LogException(ex, "Error handling connection");
return(new ConnectionResult(ConnectionResult.Reason.ClientException));
}
}
// Internal for testing.
internal static bool TryCreateServerCore(string clientDir, string pipeName, out int?processId, bool debug = false)
{
processId = null;
// The server should be in the same directory as the client
var expectedCompilerPath = Path.Combine(clientDir, ServerName);
var expectedPath = Environment.GetEnvironmentVariable("DOTNET_HOST_PATH") ?? "dotnet";
var argumentList = new string[]
{
expectedCompilerPath,
debug ? "--debug" : "",
"server",
"-p",
pipeName
};
var processArguments = ArgumentEscaper.EscapeAndConcatenate(argumentList);
if (!File.Exists(expectedCompilerPath))
{
return(false);
}
if (PlatformInformation.IsWindows)
{
// Currently, there isn't a way to use the Process class to create a process without
// inheriting handles(stdin/stdout/stderr) from its parent. This might cause the parent process
// to block on those handles. So we use P/Invoke. This code was taken from MSBuild task starting code.
// The work to customize this behavior is being tracked by https://github.com/dotnet/corefx/issues/306.
var startInfo = new STARTUPINFO();
startInfo.cb = Marshal.SizeOf(startInfo);
startInfo.hStdError = NativeMethods.InvalidIntPtr;
startInfo.hStdInput = NativeMethods.InvalidIntPtr;
startInfo.hStdOutput = NativeMethods.InvalidIntPtr;
startInfo.dwFlags = NativeMethods.STARTF_USESTDHANDLES;
var dwCreationFlags = NativeMethods.NORMAL_PRIORITY_CLASS | NativeMethods.CREATE_NO_WINDOW;
ServerLogger.Log("Attempting to create process '{0}'", expectedPath);
var builder = new StringBuilder($@"""{expectedPath}"" {processArguments}");
var success = NativeMethods.CreateProcess(
lpApplicationName: null,
lpCommandLine: builder,
lpProcessAttributes: NativeMethods.NullPtr,
lpThreadAttributes: NativeMethods.NullPtr,
bInheritHandles: false,
dwCreationFlags: dwCreationFlags,
lpEnvironment: NativeMethods.NullPtr, // Inherit environment
lpCurrentDirectory: clientDir,
lpStartupInfo: ref startInfo,
lpProcessInformation: out var processInfo);
if (success)
{
ServerLogger.Log("Successfully created process with process id {0}", processInfo.dwProcessId);
NativeMethods.CloseHandle(processInfo.hProcess);
NativeMethods.CloseHandle(processInfo.hThread);
processId = processInfo.dwProcessId;
}
else
{
ServerLogger.Log("Failed to create process. GetLastError={0}", Marshal.GetLastWin32Error());
}
return(success);
}
else
{
try
{
var startInfo = new ProcessStartInfo()
{
FileName = expectedPath,
Arguments = processArguments,
UseShellExecute = false,
WorkingDirectory = clientDir,
RedirectStandardInput = true,
RedirectStandardOutput = true,
RedirectStandardError = true,
CreateNoWindow = true
};
var process = Process.Start(startInfo);
processId = process.Id;
return(true);
}
catch
{
return(false);
}
}
}