src/thread/__timedwait.c

   1 #include <pthread.h>
   2 #include <time.h>
   3 #include <errno.h>
   4 #include "futex.h"
   5 #include "syscall.h"
   6
   7 static int do_wait(volatile int *addr, int val,
   8         clockid_t clk, const struct timespec *at, int priv)
   9 {
  10         int r;
  11         struct timespec to, *top=0;
  12
  13         if (at) {
  14                 if (at->tv_nsec >= 1000000000UL) return EINVAL;
  15                 if (clock_gettime(clk, &to)) return EINVAL;
  16                 to.tv_sec = at->tv_sec - to.tv_sec;
  17                 if ((to.tv_nsec = at->tv_nsec - to.tv_nsec) < 0) {
  18                         to.tv_sec--;
  19                         to.tv_nsec += 1000000000;
  20                 }
  21                 if (to.tv_sec < 0) return ETIMEDOUT;
  22                 top = &to;
  23         }
  24
  25         r = -__syscall_cp(SYS_futex, addr, FUTEX_WAIT, val, top);
  26         if (r == EINTR || r == EINVAL || r == ETIMEDOUT) return r;
  27         return 0;
  28 }
  29
  30 int __timedwait(volatile int *addr, int val,
  31         clockid_t clk, const struct timespec *at,
  32         void (*cleanup)(void *), void *arg, int priv)
  33 {
  34         int r, cs;
  35
  36         if (!cleanup) pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
  37         pthread_cleanup_push(cleanup, arg);
  38
  39         r = do_wait(addr, val, clk, at, priv);
  40
  41         pthread_cleanup_pop(0);
  42         if (!cleanup) pthread_setcancelstate(cs, 0);
  43
  44         return r;
  45 }