// on user thread
// the message must not be sent already
private NetSendResult SendFragmentedMessage(
NetOutgoingMessage message,
IEnumerable <NetConnection?> recipients,
NetDeliveryMethod method,
int sequenceChannel)
{
// determine minimum mtu for all recipients
int mtu = GetMTU(recipients, out int recipientCount);
if (recipientCount == 0)
{
Recycle(message);
return(NetSendResult.NoRecipients);
}
int group = GetNextFragmentGroup();
// do not send msg; but set fragmentgroup in case user tries to recycle it immediately
message._fragmentGroup = group << 2 | 1;
// create fragmentation specifics
int totalBytes = message.ByteLength;
int bytesPerChunk = NetFragmentationHelper.GetBestChunkSize(group, totalBytes, mtu);
int numChunks = totalBytes / bytesPerChunk;
if (numChunks * bytesPerChunk < totalBytes)
{
numChunks++;
}
var retval = NetSendResult.Sent;
int bitsPerChunk = bytesPerChunk * 8;
int bitsLeft = message.BitLength;
byte[] buffer = message.GetBuffer();
for (int i = 0; i < numChunks; i++)
{
NetOutgoingMessage chunk = CreateMessage();
chunk.SetBuffer(buffer, false);
chunk.BitLength = Math.Min(bitsLeft, bitsPerChunk);
chunk._fragmentGroup = group << 2 | 1;
chunk._fragmentGroupTotalBits = totalBytes * 8;
chunk._fragmentChunkByteSize = bytesPerChunk;
chunk._fragmentChunkNumber = i;
LidgrenException.Assert(chunk.BitLength != 0);
LidgrenException.Assert(chunk.GetEncodedSize() <= mtu);
Interlocked.Add(ref chunk._recyclingCount, recipientCount);
foreach (NetConnection?recipient in recipients.AsListEnumerator())
{
if (recipient == null)
{
continue;
}
NetSendResult result = recipient.EnqueueMessage(chunk, method, sequenceChannel).Result;
if (result > retval)
{
retval = result; // return "worst" result
}
}
bitsLeft -= bitsPerChunk;
}
return(retval);
}