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glibc  2.9
Defines | Functions
clock_nanosleep.c File Reference
#include <assert.h>
#include <errno.h>
#include <time.h>
#include <hp-timing.h>
#include <sysdep-cancel.h>
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Defines

#define CPUCLOCK_P(clock)   0
#define INVALID_CLOCK_P(cl)   ((cl) < CLOCK_REALTIME || (cl) > CLOCK_THREAD_CPUTIME_ID)

Functions

int clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req, struct timespec *rem)

Define Documentation

#define CPUCLOCK_P (   clock)    0

Definition at line 31 of file clock_nanosleep.c.

#define INVALID_CLOCK_P (   cl)    ((cl) < CLOCK_REALTIME || (cl) > CLOCK_THREAD_CPUTIME_ID)

Definition at line 35 of file clock_nanosleep.c.


Function Documentation

int clock_nanosleep ( clockid_t  clock_id,
int  flags,
const struct timespec req,
struct timespec rem 
)

Definition at line 43 of file clock_nanosleep.c.

{
  struct timespec now;

  if (__builtin_expect (req->tv_nsec, 0) < 0
      || __builtin_expect (req->tv_nsec, 0) >= 1000000000)
    return EINVAL;

  if (clock_id == CLOCK_THREAD_CPUTIME_ID)
    return EINVAL;          /* POSIX specifies EINVAL for this case.  */

#ifdef SYSDEP_NANOSLEEP
  SYSDEP_NANOSLEEP;
#endif

  if (CPUCLOCK_P (clock_id))
    return ENOTSUP;

  if (INVALID_CLOCK_P (clock_id))
    return EINVAL;

  /* If we got an absolute time, remap it.  */
  if (flags == TIMER_ABSTIME)
    {
      long int nsec;
      long int sec;

      /* Make sure we use safe data types.  */
      assert (sizeof (sec) >= sizeof (now.tv_sec));

      /* Get the current time for this clock.  */
      if (__builtin_expect (clock_gettime (clock_id, &now), 0) != 0)
       return errno;

      /* Compute the difference.  */
      nsec = req->tv_nsec - now.tv_nsec;
      sec = req->tv_sec - now.tv_sec - (nsec < 0);
      if (sec < 0)
       /* The time has already elapsed.  */
       return 0;

      now.tv_sec = sec;
      now.tv_nsec = nsec + (nsec < 0 ? 1000000000 : 0);

      /* From now on this is our time.  */
      req = &now;

      /* Make sure we are not modifying the struct pointed to by REM.  */
      rem = NULL;
    }
  else if (__builtin_expect (flags, 0) != 0)
    return EINVAL;
  else if (clock_id != CLOCK_REALTIME)
    /* Not supported.  */
    return ENOTSUP;

  return __builtin_expect (nanosleep (req, rem), 0) ? errno : 0;
}

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