private static async ValueTask <TransformSource> ReadAsync(PipeReader reader,
Func <TransformSource, bool> canTransform)
{
var source = new TransformSource()
{
Reader = reader,
Memory = ReadOnlySequence <byte> .Empty,
};
try
{
while (true)
{
var read = await reader.ReadAsync();
var buffer = read.Buffer;
source.IsCompleted = read.IsCompleted;
if (buffer.IsEmpty && read.IsCompleted)
{
return(source);
}
SequencePosition consumed;
//SequencePosition examined = buffer.End;
source.Memory = buffer;
if (canTransform(source))
{
// will need to be advanced and/or completed
return(source);
}
else
{
consumed = buffer.GetPosition(0);
}
reader.AdvanceTo(consumed);//, examined);
}
}
catch (Exception err)
{
reader.Complete(err);
return(source);
}
}
public static async ValueTask ContinuousReadAsync(PipeReader reader, PipeWriter writer,
Func <TransformSource, bool> canTransform,
Func <TransformSource, Task <TransformResult> > transform)
{
var source = new TransformSource(writer)
{
Reader = reader,
Memory = ReadOnlySequence <byte> .Empty,
};
try
{
while (true)
{
var read = await reader.ReadAsync();
var buffer = read.Buffer;
if (buffer.IsEmpty && read.IsCompleted)
{
break;
}
SequencePosition consumed;
//SequencePosition examined = buffer.End;
source.Memory = buffer;
if (canTransform(source))
{
var transformResult = await transform(source);
writer.Advance(transformResult.Result.Length);
//var writeResult = await writer.WriteAsync(transformResult.Result);
////if (writeResult.IsCompleted)
////{
//// writer.Complete();
//// break;
////}
var flushResult = await writer.FlushAsync();
if (flushResult.IsCanceled)
{
break;
}
consumed = source.Consumed;// buffer.GetPosition(transformResult.Consumed);
}
else
{
consumed = buffer.GetPosition(0);
}
//foreach (var memoryChunk in buffer)
//{
// // process memoryChunk.Span
// // do we have enough data to process this data?
//}
reader.AdvanceTo(consumed);//, examined);
}
reader.Complete();
writer.Complete();
}
catch (Exception err)
{
reader.Complete(err);
}
}