1#include <semaphore.h>
 2#include <limits.h>
 3#include "pthread_impl.h"
 4
 5static void cleanup(void *p)
 6{
 7	a_dec(p);
 8}
 9
10int sem_timedwait(sem_t *restrict sem, const struct timespec *restrict at)
11{
12	pthread_testcancel();
13
14	if (!sem_trywait(sem)) return 0;
15
16	int spins = 100;
17	while (spins-- && !(sem->__val[0] & SEM_VALUE_MAX) && !sem->__val[1])
18		a_spin();
19
20	while (sem_trywait(sem)) {
21		int r, priv = sem->__val[2];
22		a_inc(sem->__val+1);
23		a_cas(sem->__val, 0, 0x80000000);
24		pthread_cleanup_push(cleanup, (void *)(sem->__val+1));
25		r = __timedwait_cp(sem->__val, 0x80000000, CLOCK_REALTIME, at, priv);
26		pthread_cleanup_pop(1);
27		if (r) {
28			errno = r;
29			return -1;
30		}
31	}
32	return 0;
33}