public Diner()
{
id = instanceCount++;
left = DiningPhilosphers.forks[id];
right = DiningPhilosphers.forks[(id + 1) % DiningPhilosphers.dinerCount];
state = DinerState.Get;
Thread thread = new Thread(new ThreadStart(doStuff));
thread.Start(); // start instance's thread to doStuff()
}
public void doStuff()
{
do
{
if (state == DinerState.Get)
{
bool lockedL = false;
Monitor.TryEnter(left, ref lockedL); // try lock L
if (lockedL) // got left fork
{
left.holder = id; // left fork holder = this
bool lockedR = false;
Monitor.TryEnter(right, ref lockedR); // try lock R
if (lockedR) // lock R succeeded too.
{ // got both forks
right.holder = id; // list this as holder
state = DinerState.Eat; // Eat.
Thread.Sleep(DiningPhilosphers.rand.Next(maxWaitMs));
right.holder = -1; // no right fork holder now
Monitor.Exit(right); // unlock R
left.holder = -1; // no left fork holder now
Monitor.Exit(left); // unlock L
state = DinerState.Pon; // Ponder.
Thread.Sleep(DiningPhilosphers.rand.Next(maxWaitMs));
}
else // got left, but not right, so put left down
{
left.holder = -1; // no holder now
System.Threading.Monitor.Exit(left); // unlock L
Thread.Sleep(DiningPhilosphers.rand.Next(maxWaitMs));
}
}
else // could not get either fork
{ // wait a bit
Thread.Sleep(DiningPhilosphers.rand.Next(maxWaitMs));
}
}
else // state == DinerState.Pon
{ // done pondering, go back to get forks
state = DinerState.Get; // trying to get forks
}
} while (!end);
}
