public async Task PrepareData()
{
if (!_isDone && _bufferNeedsData)
{
_length = await _stream.ReadAsync(_buffer, 0, _buffer.Length, CancellationToken.None).ConfigureAwait(false);
if (_length == 0)
{
_isDone = true;
return;
}
_offset = 0;
_bufferNeedsData = false;
}
if (!_isDone && _bufferNeedsData2)
{
_length2 = await _stream.ReadAsync(_buffer2, 0, _buffer2.Length, CancellationToken.None).ConfigureAwait(false);
if (_length2 == 0)
{
_isDone = true;
return;
}
_offset2 = 0;
_bufferNeedsData2 = false;
}
}
/// <summary>
/// Straight copy from the reader to the writer
/// </summary>
public static async Task CopyToAsync(this IReadAsyncStream readStream, IWriteAsyncStream writeStream, CancellationToken ct)
{
// We have the double exception catching to avoid the using() from hiding the inner exception
Exception inner = null;
try
{
using (readStream)
{
try
{
var buffer = new byte[BufferSize];
int read;
do
{
ct.ThrowIfCancellationRequested();
read = await readStream.ReadAsync(buffer, 0, buffer.Length, ct).ConfigureAwait(false);
if (read > 0)
{
ct.ThrowIfCancellationRequested();
await writeStream.WriteAsync(buffer, 0, read, ct).ConfigureAwait(false);
}
} while (read > 0);
}
catch (Exception e)
{
inner = e;
throw;
}
}
}
catch (Exception)
{
if (inner != null)
{
throw inner;
}
else
{
throw;
}
}
}