1#include <semaphore.h>
2#include "pthread_impl.h"
3
4static void cleanup(void *p)
5{
6	a_dec(p);
7}
8
9int sem_timedwait(sem_t *restrict sem, const struct timespec *restrict at)
10{
11	pthread_testcancel();
12
13	if (!sem_trywait(sem)) return 0;
14
15	int spins = 100;
16	while (spins-- && sem->__val[0] <= 0 && !sem->__val[1]) a_spin();
17
18	while (sem_trywait(sem)) {
19		int r;
20		a_inc(sem->__val+1);
21		a_cas(sem->__val, 0, -1);
22		pthread_cleanup_push(cleanup, (void *)(sem->__val+1));
23		r = __timedwait_cp(sem->__val, -1, CLOCK_REALTIME, at, sem->__val[2]);
24		pthread_cleanup_pop(1);
25		if (r && r != EINTR) {
26			errno = r;
27			return -1;
28		}
29	}
30	return 0;
31}
32