public MessageDecoderResult Decode(IoSession session, IoBuffer input, IProtocolDecoderOutput output)
{
try
{
input.Skip(MIN_REQUIRED_FRAME_LENGTH);
var command = commandParser.Parse(input);
output.Write(command);
return MessageDecoderResult.OK;
}
catch (Exception ex)
{
var remoteAddr = string.Empty;
if (session != null && session.RemoteEndPoint != null) remoteAddr = session.RemoteEndPoint.ToString();
log.Error(ex, new Dictionary<string, string> { { "RemoteAddr", remoteAddr } });
return MessageDecoderResult.NotOK;
}
}
private void ManipulateIoBuffer(IoSession session, IoBuffer buffer)
{
if ((buffer.Remaining > 0) && (_removeByteProbability > _rng.Next(1000)))
{
Debug.WriteLine(buffer.GetHexDump());
// where to remove bytes ?
int pos = _rng.Next(buffer.Remaining);
// how many byte to remove ?
int count = _rng.Next(buffer.Remaining - pos) + 1;
if (count == buffer.Remaining)
count = buffer.Remaining - 1;
IoBuffer newBuff = IoBuffer.Allocate(buffer.Remaining - count);
for (int i = 0; i < pos; i++)
newBuff.Put(buffer.Get());
buffer.Skip(count); // hole
while (newBuff.Remaining > 0)
newBuff.Put(buffer.Get());
newBuff.Flip();
// copy the new buffer in the old one
buffer.Rewind();
buffer.Put(newBuff);
buffer.Flip();
Debug.WriteLine("Removed " + count + " bytes at position " + pos + ".");
Debug.WriteLine(buffer.GetHexDump());
}
if ((buffer.Remaining > 0) && (_changeByteProbability > _rng.Next(1000)))
{
Debug.WriteLine(buffer.GetHexDump());
// how many byte to change ?
int count = _rng.Next(buffer.Remaining - 1) + 1;
byte[] values = new byte[count];
_rng.NextBytes(values);
for (int i = 0; i < values.Length; i++)
{
int pos = _rng.Next(buffer.Remaining);
buffer.Put(pos, values[i]);
}
Debug.WriteLine("Modified " + count + " bytes.");
Debug.WriteLine(buffer.GetHexDump());
}
}
