/// <summary>
/// Reads a <see cref="IBufferReader{T}"/> to completion, writing to a <see cref="IBufferWriterAsync{T}"/>
/// </summary>
/// <typeparam name="T">The type of element</typeparam>
/// <param name="reader">The reader to read from</param>
/// <param name="writer">The writer to write to</param>
/// <param name="token">A cancellation token to abort the operation</param>
/// <returns>A task representing the progress fo the write operation</returns>
public static async ValueTask CopyToAsync <T>(this IBufferReader <T> reader, IBufferWriterAsync <T> writer, CancellationToken token = default)
{
while (reader.CanRead)
{
var InBuffer = reader.GetMemory(0);
if (InBuffer.IsEmpty)
{
break;
}
InBuffer.Span.CopyTo(writer.GetSpan(InBuffer.Length));
await writer.AdvanceAsync(InBuffer.Length, token);
reader.Advance(InBuffer.Length);
}
}
public static void CopyTo(this IBufferReader <byte> source, Stream target) => source.CopyTo(target, 81920); // Same buffer size as Stream.CopyTo
/// <summary>
/// Synchronously reads the bytes from the current <see cref="IBufferReader{Byte}"/> and writes them to a Stream
/// </summary>
/// <param name="source">The current buffer reader to read from</param>
/// <param name="target">The stream to write to</param>
/// <param name="blockSize">The size of the blocks to read and write</param>
public static void CopyTo(this IBufferReader <byte> source, Stream target, int blockSize)
{
if (blockSize < 0)
{
throw new ArgumentOutOfRangeException(nameof(blockSize));
}
#if NETSTANDARD2_0
byte[]? InBuffer = null;
try
{
for (; ;)
{
var Buffer = source.GetMemory(blockSize);
if (Buffer.IsEmpty)
{
break;
}
if (MemoryMarshal.TryGetArray(Buffer, out var Segment))
{
// Have the stream write directly from the source buffer
target.Write(Segment.Array, Segment.Offset, Segment.Count);
source.Advance(Segment.Count);
}
else
{
// Not a buffer we can pass to Stream.Write, so we have to copy
if (InBuffer == null)
{
InBuffer = ArrayPool <byte> .Shared.Rent(Buffer.Length);
}
var Length = Math.Min(Buffer.Length, InBuffer.Length);
Buffer.Slice(0, Length).CopyTo(InBuffer);
target.Write(InBuffer, 0, Length);
source.Advance(Length);
}
}
}
finally
{
if (InBuffer != null)
{
ArrayPool <byte> .Shared.Return(InBuffer);
}
}
#else
for (; ;)
{
var Buffer = source.GetSpan(blockSize);
if (Buffer.IsEmpty)
{
break;
}
target.Write(Buffer);
source.Advance(Buffer.Length);
}
#endif
}
