private static List <MessagePart> CreateMessageParts(Packet message, int mtuSize, RaknetSession session)
{
Memory <byte> encodedMessage = message.Encode();
if (encodedMessage.IsEmpty)
{
return(new List <MessagePart>(0));
}
if (message.IsMcpe)
{
Log.Error($"Got bedrock message in unexpected place {message.GetType().Name}");
}
int maxPayloadSizeNoSplit = mtuSize - RaknetHandler.UdpHeaderSize - 4 - GetHeaderSize(message.ReliabilityHeader, false);
bool split = encodedMessage.Length >= maxPayloadSizeNoSplit;
List <(int @from, int length)> splits = ArraySplit(encodedMessage.Length, mtuSize - RaknetHandler.UdpHeaderSize - 4 /*datagram header*/ - GetHeaderSize(message.ReliabilityHeader, split));
int count = splits.Count;
if (count == 0)
{
Log.Warn("Got zero parts back from split");
}
if (count <= 1)
{
var messagePart = MessagePart.CreateObject();
messagePart.ReliabilityHeader.Reliability = message.ReliabilityHeader.Reliability;
messagePart.ReliabilityHeader.ReliableMessageNumber = Interlocked.Increment(ref session.ReliableMessageNumber);
messagePart.ReliabilityHeader.OrderingChannel = 0;
messagePart.ReliabilityHeader.OrderingIndex = message.ReliabilityHeader.OrderingIndex;
messagePart.ReliabilityHeader.HasSplit = false;
messagePart.Buffer = encodedMessage;
return(new List <MessagePart>(1)
{
messagePart
});
}
// Stupid but scared to change it .. remove the -100 when i feel "safe"
if (session.SplitPartId > short.MaxValue - 100)
{
Interlocked.CompareExchange(ref session.SplitPartId, 0, short.MaxValue);
}
if (message.ReliabilityHeader.Reliability == Reliability.Unreliable)
{
message.ReliabilityHeader.Reliability = Reliability.Reliable;
}
int index = 0;
short splitId = (short)Interlocked.Increment(ref session.SplitPartId);
var messageParts = new List <MessagePart>(count);
foreach ((int from, int length)span in splits)
{
var messagePart = MessagePart.CreateObject();
messagePart.ReliabilityHeader.Reliability = message.ReliabilityHeader.Reliability;
messagePart.ReliabilityHeader.ReliableMessageNumber = Interlocked.Increment(ref session.ReliableMessageNumber);
messagePart.ReliabilityHeader.OrderingChannel = 0;
messagePart.ReliabilityHeader.OrderingIndex = message.ReliabilityHeader.OrderingIndex;
messagePart.ReliabilityHeader.HasSplit = count > 1;
messagePart.ReliabilityHeader.PartCount = count;
messagePart.ReliabilityHeader.PartId = splitId;
messagePart.ReliabilityHeader.PartIndex = index++;
messagePart.Buffer = encodedMessage.Slice(span.@from, span.length);
messageParts.Add(messagePart);
}
return(messageParts);
}