mirror of
				https://sourceware.org/git/glibc.git
				synced 2025-11-03 20:53:13 +03:00 
			
		
		
		
	
		
			
				
	
	
		
			102 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			102 lines
		
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* High-resolution sleep with the specified clock.
 | 
						|
   Copyright (C) 2000-2017 Free Software Foundation, Inc.
 | 
						|
   This file is part of the GNU C Library.
 | 
						|
 | 
						|
   The GNU C Library is free software; you can redistribute it and/or
 | 
						|
   modify it under the terms of the GNU Lesser General Public
 | 
						|
   License as published by the Free Software Foundation; either
 | 
						|
   version 2.1 of the License, or (at your option) any later version.
 | 
						|
 | 
						|
   The GNU C Library is distributed in the hope that it will be useful,
 | 
						|
   but WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | 
						|
   Lesser General Public License for more details.
 | 
						|
 | 
						|
   You should have received a copy of the GNU Lesser General Public
 | 
						|
   License along with the GNU C Library; if not, see
 | 
						|
   <http://www.gnu.org/licenses/>.  */
 | 
						|
 | 
						|
#include <assert.h>
 | 
						|
#include <errno.h>
 | 
						|
#include <time.h>
 | 
						|
#include <hp-timing.h>
 | 
						|
#include <sysdep-cancel.h>
 | 
						|
 | 
						|
#if HP_TIMING_AVAIL
 | 
						|
# define CPUCLOCK_P(clock) \
 | 
						|
  ((clock) == CLOCK_PROCESS_CPUTIME_ID					      \
 | 
						|
   || ((clock) & ((1 << CLOCK_IDFIELD_SIZE) - 1)) == CLOCK_THREAD_CPUTIME_ID)
 | 
						|
#else
 | 
						|
# define CPUCLOCK_P(clock) 0
 | 
						|
#endif
 | 
						|
 | 
						|
#ifndef INVALID_CLOCK_P
 | 
						|
# define INVALID_CLOCK_P(cl) \
 | 
						|
  ((cl) < CLOCK_REALTIME || (cl) > CLOCK_THREAD_CPUTIME_ID)
 | 
						|
#endif
 | 
						|
 | 
						|
 | 
						|
/* This implementation assumes that these is only a `nanosleep' system
 | 
						|
   call.  So we have to remap all other activities.  */
 | 
						|
int
 | 
						|
__clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
 | 
						|
		   struct timespec *rem)
 | 
						|
{
 | 
						|
  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;
 | 
						|
}
 | 
						|
weak_alias (__clock_nanosleep, clock_nanosleep)
 |