#include <semaphore.h>
+#include <limits.h>
#include "pthread_impl.h"
-int sem_timedwait(sem_t *sem, const struct timespec *at)
+static void cleanup(void *p)
{
- int val;
+ a_dec(p);
+}
+
+int sem_timedwait(sem_t *restrict sem, const struct timespec *restrict at)
+{
+ pthread_testcancel();
+
+ if (!sem_trywait(sem)) return 0;
+
+ int spins = 100;
+ while (spins-- && !(sem->__val[0] & SEM_VALUE_MAX) && !sem->__val[1])
+ a_spin();
- for (;;) {
- if (a_fetch_add(sem->__val, -1) > 0) return 0;
- val = a_fetch_add(sem->__val, 1);
- CANCELPT_BEGIN;
- if (val <= 0 && __timedwait(sem->__val, val, CLOCK_REALTIME, at, 0) == ETIMEDOUT) {
- errno = ETIMEDOUT;
+ while (sem_trywait(sem)) {
+ int r, priv = sem->__val[2];
+ a_inc(sem->__val+1);
+ a_cas(sem->__val, 0, 0x80000000);
+ pthread_cleanup_push(cleanup, (void *)(sem->__val+1));
+ r = __timedwait_cp(sem->__val, 0x80000000, CLOCK_REALTIME, at, priv);
+ pthread_cleanup_pop(1);
+ if (r) {
+ errno = r;
return -1;
}
- CANCELPT_END;
}
+ return 0;
}