private void ReceivePackets(double now)
{
int networkResets = 0;
int connectionResets = 0;
int availableData = 0;
try
{
for (;;)
{
try
{
if (m_socket == null)
{
return;
}
availableData = m_socket.availableData;
if (availableData <= 0)
{
return;
}
m_receiveBuffer.Reset();
double localTimeRecv;
int bytesReceived = m_socket.ReceivePacket(m_receiveBuffer.Data, 0, m_receiveBuffer.Data.Length, out m_senderRemote, out localTimeRecv);
if (bytesReceived <= 0)
{
continue;
}
m_statistics.CountPacketReceived(bytesReceived);
m_receiveBuffer.LengthBits = bytesReceived * 8;
var ipsender = (NetworkEndPoint)m_senderRemote;
if (localTimeRecv == 0)
{
localTimeRecv = NetTime.Now;
}
// lookup the endpoint (if we have a connection)
var sender = GetConnection(ipsender);
if (sender != null)
{
sender.m_statistics.CountPacketReceived(bytesReceived, localTimeRecv);
sender.m_lastPongReceived = localTimeRecv; // TODO: fulhack!
}
// try parsing the packet
try
{
// create messages from packet
while (m_receiveBuffer.PositionBits < m_receiveBuffer.LengthBits)
{
int beginPosition = m_receiveBuffer.PositionBits;
// read message header
var msg = CreateIncomingMessage();
msg.m_sender = sender;
if (!msg.ReadFrom(m_receiveBuffer, ipsender))
{
break;
}
// statistics
if (sender != null)
{
sender.m_statistics.CountMessageReceived(msg.m_type, msg.m_sequenceChannel, (m_receiveBuffer.PositionBits - beginPosition) / 8, now);
}
// handle message
HandleReceivedMessage(msg, ipsender, localTimeRecv);
}
}
catch (Exception e) // silent exception handlers make debugging impossible, comment out when you wonder "WTF is happening???"
{
// TODO: fix so logging doesn't allocate an argument array (for using params object[]).
// Enabling us to hopefully do to log calls without overhead, if the log level isn't on.
#if DEBUG // NOTE: in production it might not be desirable to log bad packets, because of targeted DoS attacks.
Log.Error(LogFlags.Socket, "Failed parsing an incoming packet from ", ipsender, ": ", e);
#endif
}
}
catch (SocketException sex)
{
if (sex.ErrorCode == 10040 || sex.SocketErrorCode == SocketError.MessageSize)
{
int bufferSize = m_receiveBuffer.Data.Length;
Log.Error(LogFlags.Socket, "Failed to read available data (", availableData, " bytes) because it's larger than the receive buffer (", bufferSize, " bytes). This might indicate that the socket receive buffer size is not correctly configured: ", sex);
}
if (sex.ErrorCode == 10052 || sex.SocketErrorCode == SocketError.NetworkReset)
{
networkResets++;
if (networkResets > 2000)
{
break;
}
}
else if (sex.ErrorCode == 10054 || sex.SocketErrorCode == SocketError.ConnectionReset)
{
connectionResets++;
if (connectionResets > 2000)
{
break;
}
}
else
{
throw;
}
}
}
}
catch (SocketException sex)
{
if (sex.ErrorCode == 10035 || sex.SocketErrorCode == SocketError.WouldBlock)
{
// NOTE: add independent ability to log warnings instead of this hack.
Log.Warning(LogFlags.Socket, "Receive Buffer is empty, ignore error: ", sex.Message);
return;
}
throw new NetException(NetTime.Now + " (" + DateTime.Now + "): Could not receive packet", sex);
}
catch (Exception ex)
{
throw new NetException(NetTime.Now + " (" + DateTime.Now + "): Could not receive packet", ex);
}
finally
{
if (networkResets > 0)
{
Log.Debug(LogFlags.Socket, NetTime.Now, " (", DateTime.Now, "): Ignored number of socket network reset errors: ", networkResets);
}
if (connectionResets > 0)
{
Log.Debug(LogFlags.Socket, NetTime.Now, " (", DateTime.Now, "): Ignored number of socket connection reset errors: ", connectionResets);
}
}
}