nsz Git - musl/blob - src/thread/sem_timedwait.c

   1 #include <semaphore.h>
   2 #include "pthread_impl.h"
   3
   4 int sem_timedwait(sem_t *sem, const struct timespec *at)
   5 {
   6         int val;
   7
   8         for (;;) {
   9                 if (a_fetch_add(sem->__val, -1) > 0) return 0;
  10                 val = a_fetch_add(sem->__val, 1)+1;
  11                 if (val==1) __wake(sem->__val, 1, 0);
  12                 if (at && at->tv_nsec >= 1000000000UL) {
  13                         errno = EINVAL;
  14                         return -1;
  15                 }
  16                 CANCELPT_BEGIN;
  17                 if (val <= 0 && __timedwait(sem->__val, val, CLOCK_REALTIME, at, 0) == ETIMEDOUT) {
  18                         errno = ETIMEDOUT;
  19                         CANCELPT_TRY;
  20                         CANCELPT_END;
  21                         return -1;
  22                 }
  23                 CANCELPT_TRY;
  24                 CANCELPT_END;
  25         }
  26 }