public static IList <byte[]> Decode(byte[] input)
{
var message = new RLPMessage(input);
while (message.Remainder.Offset < input.Length)
{
Decode(message);
}
return(message.Decoded);
}
private static void Decode(RLPMessage msg)
{
var firstByte = msg.Remainder.Array[msg.Remainder.Offset];
if (firstByte == 0x80)
{
msg.Decoded.Add(null);
msg.Remainder = msg.Remainder.Slice(1);
return;
}
// single byte
if (firstByte <= 0x7f)
{
msg.Decoded.Add(new byte[] { firstByte });
msg.Remainder = msg.Remainder.Slice(1);
return;
}
// string <55 bytes
if (firstByte <= 0xb7)
{
var itemLength = Math.Abs(128 - firstByte);
var data = firstByte == 0x80 ? new ArraySegment <byte>(new byte[0]) : msg.Remainder.Slice(1, itemLength);
msg.Decoded.Add(ArrayManipulator.SubArray(data.Array, data.Offset, data.Count));
msg.Remainder = msg.Remainder.Slice(data.Count + 1);
return;
}
// string >55 bytes
if (firstByte <= 0xbf)
{
var lengthBytesCount = Math.Abs(LargeItemOffset - firstByte);
var lengthBytes = new byte[4];
var startIndex = Math.Abs(lengthBytesCount - 5) - 1;
for (int i = 0; i < lengthBytesCount; i++)
{
lengthBytes[startIndex + i] = msg.Remainder.Array[msg.Remainder.Offset + i + 1];
}
var itemLength = ByteManipulator.GetUInt32(lengthBytes);
var data = msg.Remainder.Slice(lengthBytesCount + 1, (int)itemLength);
msg.Decoded.Add(ArrayManipulator.SubArray(msg.Remainder.Array, data.Offset, data.Count));
msg.Remainder = msg.Remainder.Slice(data.Count + lengthBytesCount + 1);
return;
}
// collection <55 bytes
if (firstByte <= 0xf7)
{
var itemLength = Math.Abs(192 - firstByte);
var data = msg.Remainder.Slice(1, itemLength).ToArray();
while (msg.Remainder.Offset < msg.Remainder.Array.Length)
{
var decoded = Decode(data);
msg.Decoded.AddRange(decoded);
msg.Remainder = msg.Remainder.Slice(msg.Remainder.Count);
}
return;
}
// collection >55 bytes
if (firstByte <= 0xff)
{
var lengthBytesCount = Math.Abs(247 - firstByte);
var lengthBytes = new byte[4];
var startIndex = Math.Abs(lengthBytesCount - 5) - 1;
for (int i = 0; i < lengthBytesCount; i++)
{
lengthBytes[startIndex + i] = msg.Remainder.Array[msg.Remainder.Offset + i + 1];
}
var itemLength = ByteManipulator.GetUInt32(lengthBytes);
var data = msg.Remainder.Slice(lengthBytesCount + 1, (int)itemLength).ToArray();
while (msg.Remainder.Offset < msg.Remainder.Array.Length)
{
var decoded = Decode(data);
msg.Decoded.AddRange(decoded);
msg.Remainder = msg.Remainder.Slice(msg.Remainder.Count);
}
return;
}
}
