fusl/src/thread/__timedwait.c

#include <pthread.h>
#include <time.h>
#include <errno.h>
#include "futex.h"
#include "syscall.h"
#include "pthread_impl.h"

int __pthread_setcancelstate(int, int*);
int __clock_gettime(clockid_t, struct timespec*);

int __timedwait_cp(volatile int* addr,
                   int val,
                   clockid_t clk,
                   const struct timespec* at,
                   int priv) {
  int r;
  struct timespec to, *top = 0;

  if (priv)
    priv = 128;

  if (at) {
    if (at->tv_nsec >= 1000000000UL)
      return EINVAL;
    if (__clock_gettime(clk, &to))
      return EINVAL;
    to.tv_sec = at->tv_sec - to.tv_sec;
    if ((to.tv_nsec = at->tv_nsec - to.tv_nsec) < 0) {
      to.tv_sec--;
      to.tv_nsec += 1000000000;
    }
    if (to.tv_sec < 0)
      return ETIMEDOUT;
    top = &to;
  }

  r = -__syscall_cp(SYS_futex, addr, FUTEX_WAIT | priv, val, top);
  if (r == ENOSYS)
    r = -__syscall_cp(SYS_futex, addr, FUTEX_WAIT, val, top);
  if (r != EINTR && r != ETIMEDOUT && r != ECANCELED)
    r = 0;

  return r;
}

int __timedwait(volatile int* addr,
                int val,
                clockid_t clk,
                const struct timespec* at,
                int priv) {
  int cs, r;
  __pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
  r = __timedwait_cp(addr, val, clk, at, priv);
  __pthread_setcancelstate(cs, 0);
  return r;
}