//This model corresponds to the incorrect first solution to the Dining
//Philosophers Problem discussed by Stallings
//in Figure 6.12 (Operating Systems, Fifth edition).
//Model constructed by Frits Vaandrager on 21/3/06
const int M = 5; //Number of semaphores
const int N = 5; //Number of philosophers
chan semWait[M][N];
chan semSignal[M][N];
chan semGo[M][N];
Philosopherconst int pid
void think(){}
void eat(){}
Semaphoreconst int id, const int queue_size, const int init_val//The value of the semaphore
int count = init_val;
//The queue of the semaphore
//value -1 denotes an empty array entry
int[-1,N-1] queue[queue_size];
//An auxiliary variable used to temporarily store process id
meta int[0,N-1] q;
void initialize ()
{
for (i : int[0,queue_size-1])
{queue[i] = -1;}
}
void deQueue ()
{
for (i : int[1,queue_size-1])
queue[i-1] = queue[i];
queue[queue_size-1] = -1;
}
void enQueue (int p)
{
int i = 0;
while (queue[i]>=0){i++;};
queue[i]=p;
}
int[0,N-1] headQueue ( )
{
return queue[0];
}
bool fullQueue ( )
{
for (i : int[0,queue_size-1])
{
if (queue[i]==-1) {return false;}
}
return true;
}overflow//Insert process assignments.
Fork0 = Semaphore(0,1,1);
Fork1 = Semaphore(1,1,1);
Fork2 = Semaphore(2,1,1);
Fork3 = Semaphore(3,1,1);
Fork4 = Semaphore(4,1,1);
Philosopher0 = Philosopher(0);
Philosopher1 = Philosopher(1);
Philosopher2 = Philosopher(2);
Philosopher3 = Philosopher(3);
Philosopher4 = Philosopher(4);
//Edit system definition.
system Fork0, Fork1, Fork2, Fork3, Fork4, Philosopher0, Philosopher1, Philosopher2, Philosopher3, Philosopher4;