/// <summary>
/// Relay all received by one stream to another stream.
/// </summary>
public static Task RelayToAsync(
this INetworkStream readStream,
INetworkStream writeStream,
CancellationToken token)
{
return(Task.Run(async() =>
{
// Use a buffer that is as large as possible, but does not exceed
// any of the two stream's capabilities.
int bufferSize = Math.Min(
writeStream.MaxWriteSize,
Math.Max(
MaxBufferSize,
readStream.MinReadSize));
var buffer = new byte[bufferSize];
while (true)
{
token.ThrowIfCancellationRequested();
try
{
TraceSources.Compute.TraceVerbose(
"NetworkStream [{0} > {1}]: Reading...",
readStream,
writeStream);
int bytesRead = await readStream.ReadAsync(
buffer,
0,
buffer.Length,
token).ConfigureAwait(false);
if (bytesRead > 0)
{
TraceSources.Compute.TraceVerbose(
"NetworkStream [{0} > {1}]: Relaying {2} bytes",
readStream,
writeStream,
bytesRead);
await writeStream.WriteAsync(buffer, 0, bytesRead, token).ConfigureAwait(false);
}
else
{
TraceSources.Compute.TraceVerbose(
"NetworkStream [{0} > {1}]: gracefully closed connection",
readStream,
writeStream);
// Propagate.
await writeStream.CloseAsync(token).ConfigureAwait(false);
break;
}
}
catch (NetworkStreamClosedException e)
{
TraceSources.Compute.TraceWarning(
"NetworkStream [{0} > {1}]: forcefully closed connection: {2}",
readStream,
writeStream,
e.Message);
// Propagate.
await writeStream.CloseAsync(token).ConfigureAwait(false);
break;
}
catch (Exception e)
{
TraceSources.Compute.TraceWarning(
"NetworkStream [{0} > {1}]: Caught unhandled exception: {2} {3}",
readStream,
writeStream,
e.Message,
e.StackTrace);
throw;
}
}
}));
}