Valhalla Legends Archive

Using blocking sockets in c#, I have a timer on 10ms delay that checks for new data like so:

static void timerTick()
       {
           if (stmBnet.DataAvailable)
           {

               int i = stmBnet.Read(RecvData, 0, size);

               if (i > 0)
               {
                   //data exists, separate it up and remove the null bytes

                   SplitPacket(RecvData);
                   if (DataQ.Count > 0)
                   {
                       //parse the separated packets
                       ParsePackets();
                   }
                   RecvData = new byte[size]; //reset the buffer
               }
           }
       }


I receive the data fine but the issue is that sometimes it clumps together and adds a plethora of trailing 0x00 (null) bytes. Therefore I wrote the packet splitting function, which splits up thepackets and places the data into a queue (DataQ):

static void SplitPacket(byte[] bData)
       {
           for (int i = 0; i < bData.Length; i++)
           {
               if (bData[i] == (byte)0xff)
               {
                   //found 0xFF, check if it's a header
                   if (bData.Length >= i + 2) //check that we can move up 2 more bytes to check for packet size
                   {
                       //i is still the location of 0xFF
                       byte packetid = bData[i + 1];
                       int packetsize = BitConverter.ToInt16(bData, i + 2);
                       if (bData.Length >= i + (packetsize - 1) && packetsize > 3 && packetsize < 512)
                       {
                           Console.WriteLine("Packet ID: 0x{0} :: Size: {1}", packetid.ToString("x2"), packetsize);
                           string splitPacket = Encoding.Unicode.GetString(bData, i, packetsize);
                           DataFormatter.WriteToConsole(Encoding.Unicode.GetBytes(splitPacket));
                           DataQ.Add(splitPacket);
                       }
                   }
               }
           }
       }


I then go about parsing the items in the queue. However, for some reason, it will randomly occur that the end of my parsed packets have the bytes: 0xFD and 0xFF, and are 1 beyond the split size.. for example, if the real packet data is

FF 30 09 00 01 00 00 00 00

, the packet splitter function will somehow end up with

FF 30 09 00 01 00 00 00 FD FF

instead.

I think it has something to do with the data being extracted as a string:

string splitPacket = Encoding.Unicode.GetString(bData, i, packetsize);
But I'm not sure how to extract in the middle of a byte array (the equivalent of .substring for byte[]). I think the null terminator on the end of packets is getting lost when it's extracted.

I'm basically looking for the C# equivalent of the java method extractBytes.

Nevermind, ended up using Array.copy. Revised funct:

static void SplitPacket(byte[] bData)
        {
            for (int i = 0; i < bData.Length; i++)
            {
                if (bData[i] == (byte)0xff)
                {
                    //found FF, check if it's a header
                    if (bData.Length >= i + 2) //check that we can move up 2 more bytes to check for packet size
                    {
                        byte packetid = bData[i + 1];
                        int packetsize = BitConverter.ToInt16(bData, i + 2);
                        if (bData.Length >= i + (packetsize - 1) && packetsize > 3 && packetsize < 512)
                        {
                            //we have enough room to separate the packet, it is a valid BNCS packet\
                            Console.WriteLine("Packet ID: 0x{0} :: Size: {1}", packetid.ToString("x2"), packetsize);

                            byte[] tempData = new byte[packetsize];
                            Array.Copy(bData, i, tempData, 0, packetsize);
                            DataFormatter.WriteToConsole(tempData);

                            DataQ.Add(tempData);
                        }
                    }
                }
            }
        }

I'll leave the thread here on the off chance that someone else has a similar issue.