protected override void Encode(IChannelHandlerContext context, IByteBuffer input, IByteBuffer output)
{
while (input.IsReadable())
{
if (input.ReadableBytes % Frame.BlockSize != 0)
{
throw new CorruptedFrameException($"Frame prepared for sending was in incorrect format: length was {input.ReadableBytes}");
}
FrameHeaderReader.FrameInfo frame = _headerReader.ReadFrameHeader(input);
// 0 if the buffer has enough writable bytes, and its capacity is unchanged.
// 1 if the buffer does not have enough bytes, and its capacity is unchanged.
// 2 if the buffer has enough writable bytes, and its capacity has been increased.
// 3 if the buffer does not have enough bytes, but its capacity has been increased to its maximum.
int code = output.EnsureWritable(Frame.HeaderSize + Frame.MacSize + frame.PayloadSize + Frame.MacSize, true);
WriteHeader(output);
WriteHeaderMac(output);
for (int i = 0; i < frame.PayloadSize / Frame.BlockSize; i++)
{
WritePayloadBlock(input, output);
}
WritePayloadMac(output);
}
}
protected override void Decode(IChannelHandlerContext context, IByteBuffer input, List <object> output)
{
// Note that each input is a full frame header16|payload that are automatically released by the base class.
// If the input is not a full and valid frame we can throw as this is an unexpected behaviour from the
// decoder up the pipeline.
// Moreover we will never receive more than a full packet in a single input so the input buffer
// is expected to have no readable bytes after the merging operation.
if (_logger.IsTrace)
{
_logger.Trace("Merging frames");
}
if (input.ReferenceCount != 1)
{
throw new IllegalReferenceCountException(input.ReferenceCount);
}
FrameHeaderReader.FrameInfo frame = _headerReader.ReadFrameHeader(input);
if (frame.IsFirst)
{
ReadFirstChunk(context, input, frame);
}
else
{
ReadChunk(input, frame);
}
if (!_zeroPacket.Content.IsWritable())
{
input.SkipBytes(frame.Padding);
output.Add(_zeroPacket);
_zeroPacket = null;
if (input.IsReadable())
{
throw new CorruptedFrameException($"{nameof(ZeroFrameMerger)} received a corrupted frame - {input.ReadableBytes} longer than expected");
}
}
}
private void ReadFirstChunk(IChannelHandlerContext context, IByteBuffer input, FrameHeaderReader.FrameInfo frame)
{
byte packetTypeRlp = input.ReadByte();
IByteBuffer content;
if (frame.IsChunked)
{
content = context.Allocator.Buffer(frame.TotalPacketSize - 1);
}
else
{
content = input.ReadSlice(frame.Size - 1);
// Since we will call release in the next handler and we use a derived buffer here
// we need to call Retain to prevent the buffer from being released twice
// (once in the next handler and once in the base class).
content.Retain();
}
_zeroPacket = new ZeroPacket(content);
_zeroPacket.PacketType = GetPacketType(packetTypeRlp);
// If not chunked then we already used a slice of the input,
// otherwise we need to read into the freshly allocated buffer.
if (frame.IsChunked)
{
input.ReadBytes(_zeroPacket.Content, frame.Size - 1);
// do not call Release since the input buffer is managed by
}
}
private void ReadChunk(IByteBuffer input, FrameHeaderReader.FrameInfo frame)
{
input.ReadBytes(_zeroPacket.Content, frame.Size);
}