int
stoplight(int nargs, char **args)
{
(void)nargs;
(void)args;
int i, direction, turn, err=0;
char name[32];
stoplightMenuSemaphore = sem_create("Stoplight Driver Semaphore", 0);
if (stoplightMenuSemaphore == NULL) {
// 08 Feb 2012 : GWA : Probably out of memory, or you broke our
// semaphores! Panicing might be an overreaction, but why not?
panic("stoplight: sem_create failed.\n");
}
// 13 Feb 2012 : GWA : Students are smarter than me.
stoplight_init();
for (i = 0; i < NCARS; i++) {
direction = random() % 4;
turn = random() % 3;
snprintf(name, sizeof(name), "Car Thread %d", i);
switch(turn) {
case 0:
err = thread_fork(name, gostraight, stoplightMenuSemaphore,
direction, NULL);
break;
case 1:
err = thread_fork(name, turnleft, stoplightMenuSemaphore, direction,
NULL);
break;
case 2:
err = thread_fork(name, turnright, stoplightMenuSemaphore, direction,
NULL);
break;
}
}
for (i = 0; i < NCARS; i++) {
P(stoplightMenuSemaphore);
}
sem_destroy(stoplightMenuSemaphore);
// 13 Feb 2012 : GWA : Students are WAY smarter than me, including Nikhil
// Londhe.
stoplight_cleanup();
return 0;
}
int stoplight(int nargs, char **args) {
(void) nargs;
(void) args;
int i, direction, turn, err = 0;
char name[32];
stoplightMenuSemaphore = sem_create("Stoplight Driver Semaphore", 0);
if (stoplightMenuSemaphore == NULL ) {
panic("stoplight: sem_create failed.\n");
}
stoplight_init();
for (i = 0; i < NCARS; i++) {
direction = random() % 4;
turn = random() % 3;
snprintf(name, sizeof(name), "Car Thread %d", i);
switch (turn) {
random_yielder(PROBLEMS_MAX_YIELDER);
case 0:
err = thread_fork(name, gostraight,
stoplightMenuSemaphore, direction,
NULL );
break;
case 1:
err = thread_fork(name, turnleft,
stoplightMenuSemaphore, direction,
NULL );
break;
case 2:
err = thread_fork(name, turnright,
stoplightMenuSemaphore, direction,
NULL );
break;
}
}
for (i = 0; i < NCARS; i++) {
P(stoplightMenuSemaphore);
}
sem_destroy(stoplightMenuSemaphore);
stoplight_cleanup();
return 0;
}
