protected void Transmit(Frame token)
{
// Send until THT reached
// first send the token ack
Frame sendFrame;
Frame recieveFrame;
byte[] bFrame;
String[] splitInput;
int dataSize;
this.THT = 1040;
Frame newToken;
// send ack for token
sendFrame = new Frame(0, token.SA, this.nodeNum, null);
sendFrame.FS = 2;
bFrame = sendFrame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
// read from file, and build frame from it
while (true)
{
// tokenize the input line
splitInput = this.inputFile[index].Split(new char[] { ',' });
dataSize = Convert.ToByte(splitInput[1]); // the size of data is always in the second array element
if (dataSize > 254)
{
Console.WriteLine("LOL BAD STUFF");
}
if (this.THT < dataSize)
{
// not enough THT to send the frame, send a token
newToken = new Token(0, 0, this.nodeNum);
bFrame = newToken.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
recieveFrame = Frame.MakeFrame(Receive());
Debug.Assert(recieveFrame.DA == this.nodeNum);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
return;
}
// otherwise, build and send the frame
sendFrame = new Frame(0, Convert.ToByte(splitInput[0]), this.nodeNum, new System.Text.UTF8Encoding().GetBytes(splitInput[2]));
bFrame = sendFrame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
THT -= sendFrame.size;
// recieve ack
while (true)
{
recieveFrame = Frame.MakeFrame(Receive());
Debug.Assert(recieveFrame.SA == this.nodeNum);
Debug.Assert(recieveFrame.DA == sendFrame.DA);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
// frame wasn't accepted, resend
if (recieveFrame.FS == 3)
{
// is there enough THT to resend?
if (this.THT > sendFrame.size)
{
// send it!
sendStream.Write(bFrame, 0, bFrame.Length);
THT -= sendFrame.size;
continue;
}
else
{
// send the token along
newToken = new Token(0, 0, this.nodeNum);
bFrame = newToken.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
recieveFrame = Frame.MakeFrame(Receive());
Debug.Assert(recieveFrame.DA == this.nodeNum);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
return;
}
}
else
{
// frame was successfully recieved, move onto the next one
this.index++;
if (this.index >= this.inputFile.Length)
{
// nothing more to send
newToken = new Token(0, 0, this.nodeNum);
bFrame = newToken.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
recieveFrame = Frame.MakeFrame(Receive());
Debug.Assert(recieveFrame.DA == this.nodeNum);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
return;
}
break;
}
}
}
}
protected void Transmit(Frame token)
{
// Send until THT reached
// first send the token ack
Frame sendFrame;
Frame recieveFrame;
byte[] bFrame;
int dataSize;
this.THT = 1040;
Frame newToken;
Queue<Frame> sendQueue;
Object locker;
// send ack for token
sendFrame = new Frame(0, token.SA, this.nodeNum, null);
sendFrame.FS = 2;
bFrame = sendFrame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
// setup which buffer to send from
if (bridgeNumber == 1)
{
lock (buf1Locker)
{
sendQueue = buffer1;
locker = buf1Locker;
}
}
else
{
lock (buf2Locker)
{
sendQueue = buffer2;
locker = buf1Locker;
}
}
// read from buffer and send it
while (true)
{
// get the next frame to send and its size
lock (locker)
{
sendFrame = sendQueue.Peek();
}
dataSize = sendFrame.size;
if (this.THT < dataSize)
{
// not enough THT to send the frame, send a token
newToken = new Token(0, 0, this.nodeNum);
bFrame = newToken.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
recieveFrame = Frame.MakeFrame(Receive());
//Debug.Assert(recieveFrame.DA == this.nodeNum);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
return;
}
// otherwise, send the frame
bFrame = sendFrame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
THT -= sendFrame.size;
// recieve ack
while (true)
{
recieveFrame = Frame.MakeFrame(Receive());
//Debug.Assert(recieveFrame.SA == this.nodeNum);
//Debug.Assert(recieveFrame.DA == sendFrame.DA);
//Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
// if it needs to be setup into the routing table
if (recieveFrame.AC == 4)
{
// if the frame recieved doesn't have the FS changed, nothing processed it
if (recieveFrame.FS == 0)
{
lock (locker)
{
sendQueue.Dequeue();
if (sendQueue.Count == 0)
{
// nothing more to send
newToken = new Token(0, 0, this.nodeNum);
bFrame = newToken.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
recieveFrame = Frame.MakeFrame(Receive());
//Debug.Assert(recieveFrame.DA == this.nodeNum);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
return;
}
}
break;
}
// otherwise, add it to the routing table
else
{
lock (lookupTableLocker)
{
if (!lookupTable.Contains(sendFrame.DA))
{
lookupTable.Add(sendFrame.DA, bridgeNumber);
lock (logLocker)
{
logFile.WriteLine(DateTime.Now.ToString() + " " + sendFrame.DA + " added to the routting table");
}
}
}
// make sure that if it needs to be resent, it doesn't get added again
sendFrame.AC = 0;
break;
}
}
// frame wasn't accepted, resend
else if (recieveFrame.FS == 3)
{
// is there enough THT to resend?
if (this.THT > sendFrame.size)
{
lock (logLocker)
{
//logFile.WriteLine(DateTime.Now.ToString() + " resending frame to " + sendFrame.DA + " from " + sendFrame.SA);
}
// send it!
sendStream.Write(bFrame, 0, bFrame.Length);
THT -= sendFrame.size;
continue;
}
else
{
// send the token along
newToken = new Token(0, 0, this.nodeNum);
bFrame = newToken.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
recieveFrame = Frame.MakeFrame(Receive());
//Debug.Assert(recieveFrame.DA == this.nodeNum);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
return;
}
}
else
{
// frame was successfully recieved, move onto the next one
lock (locker)
{
sendQueue.Dequeue();
if (sendQueue.Count == 0)
{
// nothing more to send
newToken = new Token(0, 0, this.nodeNum);
bFrame = newToken.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
recieveFrame = Frame.MakeFrame(Receive());
//Debug.Assert(recieveFrame.DA == this.nodeNum);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
return;
}
}
break;
}
}
}
}
// monitors run, since it will only accept a token
public override void Run()
{
// connect with neighboring nodes
this.Connect();
// Accept incoming connection and wait for
// right neighbor to be ready.
// create the first token
Frame sendFrame = new Token(0, 0, 0);
byte[] bFrame = sendFrame.ToBinary();
Frame recieveFrame;
Frame newToken;
Frame frame;
// send it!
sendStream.Write(bFrame, 0, bFrame.Length);
recieveFrame = Frame.MakeFrame(Receive());
Debug.Assert(recieveFrame.DA == this.nodeNum);
Debug.Assert(recieveFrame.FS == 2 || recieveFrame.FS == 3);
try
{
while (true)
{
// listen state
// recieve frame, check if token
frame = Frame.MakeFrame(Receive());
if (frame is Token)
{
// if it was sent by the monitor, everyone is done sending
if (frame.SA == this.nodeNum)
{
// send a frame with the finished bit enabled
sendFrame = new Frame(2, 255, 0, null);
bFrame = sendFrame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
}
// if the token wasn't sent by the monitor, must send ack
else
{
sendFrame = new Frame(0, frame.SA, this.nodeNum, null);
sendFrame.FS = 2;
bFrame = sendFrame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
}
// otherwise send a new token if the SA is not the monitor
newToken = new Token(0, this.nodeNum, this.nodeNum);
bFrame = newToken.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
frame = Frame.MakeFrame(Receive());
if (frame.SA == this.nodeNum)
{
// send a frame with the kill bit enabled
sendFrame = new Frame(2, lastNode, 0, null);
bFrame = sendFrame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
}
else
{
Debug.Assert(frame.DA == this.nodeNum);
Debug.Assert(frame.FS == 2 || frame.FS == 3);
}
}
// otherwise, check if the bridge is telling it to shutdown
else if (frame.AC == 1)
{
Console.WriteLine("Exterminate list");
// send a frame with the kill bit enabled
sendFrame = new Frame(1, lastNode, 0, null);
bFrame = sendFrame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
break;
}
else
{
bFrame = frame.ToBinary();
sendStream.Write(bFrame, 0, bFrame.Length);
}
}
}
finally
{
// Close all open resources (i.e. sockets!)
Console.WriteLine("Monitor node EX-TERM-INATED!");
this.recieveStream.Close();
this.recieveClient.Close();
}
}
// what runs on startup of node
public virtual void Run()
{
int destRing = -1;
bool shouldTransmit = false;
bool shutdown;
// connect with neighboring nodes
this.Connect();
Console.WriteLine(this.nodeNum + "Connected");
lock (logLocker)
{
logFile.WriteLine(DateTime.Now.ToString() + " Connected with token ring " + this.bridgeNumber);
}
Random rand = new Random();
byte[] bFrame;
// Accept incoming connection and wait for
// right neighbor to be ready.
try
{
while (true)
{
// listen state
// recieve frame, check if token
Frame frame = Frame.MakeFrame(Receive());
if (frame is Token)
{
// check to see if the thread's buffer has something to transmit
if (bridgeNumber == 1)
{
lock (buf1Locker)
{
if (buffer1.Count != 0)
shouldTransmit = true;
else
shouldTransmit = false;
}
}
else
{
lock (buf2Locker)
{
if (buffer2.Count != 0)
shouldTransmit = true;
else
shouldTransmit = false;
}
}
// if it does, enter transmit state
if (shouldTransmit)
{
Transmit(frame);
}
else
{
// otherwise, send the token along
bFrame = frame.ToBinary();
this.sendStream.Write(bFrame, 0, bFrame.Length);
}
}
// shutdown signal.
else if (frame.AC == 2 || frame.DA == 255)
{
Console.WriteLine(this.bridgeNumber + " is ready to shutdown");
lock (logLocker)
{
logFile.WriteLine(DateTime.Now.ToString() + " Token ring " + this.bridgeNumber + " is ready to shutdown");
}
// figure out if the other side is ready to shutdown
lock (shutdownLocker)
{
shutdown = shouldShutdown;
if (!shouldShutdown)
shouldShutdown = true;
}
// if not ready to shutdown, go into infinite send state until a shutdown signal comes through the buffer
if (!shutdown)
{
while (true)
{
// check to see if the thread's buffer has something to transmit
if (bridgeNumber == 1)
{
lock (buf1Locker)
{
if (buffer1.Count != 0)
shouldTransmit = true;
else
shouldTransmit = false;
}
}
else
{
lock (buf2Locker)
{
if (buffer2.Count != 0)
shouldTransmit = true;
else
shouldTransmit = false;
}
}
if (shouldTransmit)
{
if (shutdownTransmit())
{
break; // shutdown
}
else
Thread.Sleep(10); // otherwise, sleep for 10 ms
}
else
{
Thread.Sleep(10); // if nothing in the queue, sleep and try again
}
}
break;
}
// otherwise, send shutdown signal to both rings and shutdown
else
{
frame = new Frame(1, 0, 255, null);
if (bridgeNumber == 1)
{
lock (buf2Locker)
{
buffer2.Enqueue(new Frame(frame.AC, frame.DA, frame.SA, frame.data));
}
bFrame = frame.ToBinary();
this.sendStream.Write(bFrame, 0, bFrame.Length);
}
else
{
lock (buf1Locker)
{
buffer1.Enqueue(new Frame(frame.AC, frame.DA, frame.SA, frame.data));
}
bFrame = frame.ToBinary();
this.sendStream.Write(bFrame, 0, bFrame.Length);
}
}
break;
}
// send the frame to the proper ring
else
{
// check for which ring the frame goes to
lock (lookupTableLocker)
{
if (lookupTable.Contains(frame.DA))
destRing = (int)lookupTable[frame.DA];
else
destRing = -1;
}
// if it is unknown, add it to both buffers
if (destRing == -1)
{
// set the bit to be checked later for adding to lookup table
frame.AC = 4;
// add it to both buffers
lock (buf1Locker)
{
buffer1.Enqueue(new Frame(frame.AC, frame.DA, frame.SA, frame.data));
}
lock (buf2Locker)
{
buffer2.Enqueue(new Frame(frame.AC, frame.DA, frame.SA, frame.data));
}
// setup "faked" ack
frame.FS = 2; // frame accepted
frame.AC = 0; // reset the AC bit to avoid confusion
}
// if it is known, add it to that buffer
else
{
if (destRing == 1)
{
lock (buf1Locker)
{
buffer1.Enqueue(new Frame(frame.AC, frame.DA, frame.SA, frame.data));
}
if (this.bridgeNumber != destRing)
{
lock (logLocker)
{
logFile.WriteLine(DateTime.Now.ToString() + " Sending frame to Token Ring " + destRing + ". Source=" + frame.SA + " Destination=" + frame.DA);
}
}
}
else
{
lock (buf2Locker)
{
buffer2.Enqueue(new Frame(frame.AC, frame.DA, frame.SA, frame.data));
}
if (this.bridgeNumber != destRing)
{
lock (logLocker)
{
logFile.WriteLine(DateTime.Now.ToString() + " Sending frame to Token Ring " + destRing + ". Source=" + frame.SA + " Destination=" + frame.DA);
}
}
}
// setup "faked" ack
frame.FS = 2;
}
// send ack
bFrame = frame.ToBinary();
this.sendStream.Write(bFrame, 0, bFrame.Length);
}
}
}
finally
{
// Close all open resources (i.e. sockets!)
Console.WriteLine(this.nodeNum + " " + this.bridgeNumber + " Exterminate!");
lock (logLocker)
{
logFile.WriteLine(DateTime.Now.ToString() + " Token ring " + this.bridgeNumber + " is shutting down");
}
if (this.bridgeNumber == 1)
{
Thread.Sleep(20);
lock (logLocker)
{
logFile.Close();
}
}
this.recieveStream.Close();
this.recieveClient.Close();
}
}
