int main() {
srand(time(0));
//let user specify parameters
printf("Specify the probability of a truck arriving, as a percentage: ");
scanf("%d", &probabiltyOfTruckArriving);
printf("Specify the max time interval between two vehicle arrivals, in milliseconds: ");
scanf("%d", &maxTimeBetweenArrivals);
initialize();
//create the vehicle
int pid = fork();
if(pid == 0) {
//child, its vehicle
vehicle();
return 0;
}
vehicleProcessId = pid;
captain();
terminate();
return 0;
}
int main(){
// Initializations.
msg_t buffer;
int len = sizeof(msg_t) - sizeof(long);
int truck_prob = 50;
int spawn_interval = 300;
int ferry_travel = 500;
printf("Enter a probability within [0..100] that a truck arrives in place of a car: ");
scanf("%d", &truck_prob);
printf("\nEnter the maximum time interval in milleseconds between vehicle arrivals: ");
scanf("%d", &spawn_interval);
printf("\nEnter the Ferry travel time in milleseconds : ");
scanf("%d", &ferry_travel);
key_t key_arrivals;
key_arrivals = ftok(".","arr");
int q_arrivals = msgget(key_arrivals, IPC_CREAT | 0660);
printf("Arrival queue : %d\n", q_arrivals);
key_t key_early;
key_early = ftok(".","ear");
int q_early = msgget(key_early, IPC_CREAT | 0660);
printf("Early queue : %d\n", q_early);
key_t key_late;
key_late = ftok(".","lat");
int q_late = msgget(key_late, IPC_CREAT | 0660);
printf("Late queue : %d\n", q_late);
key_t key_ferry;
key_ferry = ftok(".","fer");
int q_ferry = msgget(key_ferry, IPC_CREAT | 0660);
printf("Ferry deck : %d\n", q_ferry);
key_t key_boarded;
key_boarded = ftok(".","boa");
int q_boarded = msgget(key_boarded, IPC_CREAT | 0660);
printf("Boarded vehicles: %d\n", q_boarded);
pid_t capt;
// Spawn captain process to manage the ferry.
if( (capt = fork()) == 0 ) captain( ferry_travel+1, q_arrivals, q_early, q_late, q_ferry, q_boarded, len );
// End Initializations.
// Keep track of children that captain did not terminate.
int n = 1000;
pid_t* childArray = malloc(n*sizeof(pid_t));
pid_t child;
int child_counter = 0;
// Start vehicle spawning until ferry loads are done.
int timeGap;
while( !waitpid(capt, NULL, WNOHANG) ){
timeGap = (rand()%spawn_interval) + 1;
usleep(timeGap*1000);
if( (child = fork()) == 0 ){
vehicle(truck_prob, q_arrivals, q_boarded, len);
}else{
childArray[child_counter] = child;
};
child_counter++;
if( child_counter == n ){
n = n*2;
childArray = realloc(childArray, n*sizeof(pid_t));
};
};
// Remove all child processes.
int v = 0;
for( v; v < child_counter; v++ ){
kill(childArray[v], SIGTERM);
};
free(childArray);
// Remove all queues.
msgctl(q_arrivals, IPC_RMID, 0);
msgctl(q_late, IPC_RMID, 0);
msgctl(q_early, IPC_RMID, 0);
msgctl(q_ferry, IPC_RMID, 0);
msgctl(q_boarded, IPC_RMID, 0);
return 0;
}
