public async Task <byte[]> ReadAsync(ResponseReadingFinalizer responseReadingFinalizer, TimeSpan timeout)
{
using (var timeoutCancellationTokenSource = new CancellationTokenSource(timeout))
{
return(await ReadAsync(responseReadingFinalizer, timeoutCancellationTokenSource.Token, null));
}
}
public async Task <byte[]> ReadAsync(ResponseReadingFinalizer responseReadingFinalizer, TimeSpan timeout, CancellationToken externalCancellationToken)
{
if (timeout == TimeSpan.Zero)
{
return(await ReadAsync(responseReadingFinalizer, null, externalCancellationToken));
}
else
{
using (var timeoutCancellationTokenSource = new CancellationTokenSource(timeout))
{
return(await ReadAsync(responseReadingFinalizer, timeoutCancellationTokenSource.Token, externalCancellationToken));
}
}
}
private async Task <byte[]> ReadAsync(ResponseReadingFinalizer responseReadingFinalizer, CancellationToken?timeoutCancellationToken, CancellationToken?externalCancellationToken)
{
EnsureOpened();
Assure.ArgumentNotNull(responseReadingFinalizer, nameof(responseReadingFinalizer));
if (timeoutCancellationToken == null && externalCancellationToken == null)
{
throw new ArgumentException($"At least either '{nameof(timeoutCancellationToken)}' or '{nameof(externalCancellationToken)}' should be passed.");
}
CancellationTokenSource linkedTokenSource = null;
CancellationToken? readContinuationTimeoutCancellationToken = null;
try
{
try
{
CancellationToken cancellationToken;
if (timeoutCancellationToken != null && externalCancellationToken != null)
{
linkedTokenSource = CancellationTokenSource.CreateLinkedTokenSource(timeoutCancellationToken.Value, externalCancellationToken.Value);
cancellationToken = linkedTokenSource.Token;
}
else
{
cancellationToken = timeoutCancellationToken ?? externalCancellationToken.Value;
}
var responseBytes = new List <byte>();
var isFirstRead = true;
// ReSharper disable LoopVariableIsNeverChangedInsideLoop
do
{
const int readBufferSize = 256;
byte[] readBytes;
if (isFirstRead)
{
isFirstRead = false;
// wait with general cancellation token
readBytes = await _deviceIoPort.ReadAsync(readBufferSize, InputStreamOptions.Partial, cancellationToken);
}
else
{
// after first bytes are read, wait max 1s for the following ones
using (var readContinuationTimeoutCancellationSource = new CancellationTokenSource(TimeSpan.FromSeconds(1)))
{
readContinuationTimeoutCancellationToken = readContinuationTimeoutCancellationSource.Token;
using (var linkedContinuationTokenSource = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken, readContinuationTimeoutCancellationToken.Value))
{
readBytes = await _deviceIoPort.ReadAsync(readBufferSize, InputStreamOptions.Partial, linkedContinuationTokenSource.Token);
}
}
}
responseBytes.AddRange(readBytes);
}while (!responseReadingFinalizer(responseBytes));
// ReSharper restore LoopVariableIsNeverChangedInsideLoop
return(responseBytes.ToArray());
}
catch (OperationCanceledException)
{
// rethrow specific token exception (for case of linked sources)
externalCancellationToken?.ThrowIfCancellationRequested();
timeoutCancellationToken?.ThrowIfCancellationRequested();
readContinuationTimeoutCancellationToken?.ThrowIfCancellationRequested();
throw new InvalidFlowStateException($"'{nameof(ReadAsync)}' - at least one of cancellation tokens should trigger exception.");
}
}
catch (OperationCanceledException ex)
{
if (ex.CancellationToken == timeoutCancellationToken)
{
throw new DeviceIoPortTimeoutException();
}
else if (ex.CancellationToken == readContinuationTimeoutCancellationToken)
{
throw new DeviceIoPortTimeoutException(partialRead: true);
}
else
{
throw;
}
}
finally
{
linkedTokenSource?.Dispose();
}
}
public async Task <byte[]> ReadAsync(ResponseReadingFinalizer responseReadingFinalizer, CancellationToken externalCancellationToken)
{
return(await ReadAsync(responseReadingFinalizer, null, externalCancellationToken));
}