Homework: Dining Philosophers

Pseudocode for Dining Philosophers

pseudomonitor DiningPhilosophers 
{
   enum State {THINKING, HUNGRY, EATING};
   State[] states = new State[5];
   Condition[] self = new Condition[5];


   public DiningPhilosophers {
      for(int i = 0; i < 5; i++) {
         state[i] = State.thinking;
      }
   }


   public void takeForks(int i) {
      state[i] = State.HUNGRY;
      test(i);
      if(state[i] != State.EATING)
         self[i].wait;
   }


   public void returnForks(int i) {
      state[i] = State.THINKING;
      // test left and right neighbors
      test((i + 4) % 5);
      test((i + 1) % 5);
   }

   private void test(int i) {
      if( (state[(i + 4) % 5] != State.EATING) &&
         (state[i] == State.HUNGRY) &&
         (state[(i + 1) % 5] != State.EATING) ) {
            state[i] = State.EATING;
            self[i].signal;
         }
   }
}