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	* include/time.h: Add librt_hidden_proto definition for clock_gettime. * sysdeps/generic/clock_gettime.c: Add librt_hidden_def. * sysdeps/unix/clock_gettime.c: Likewise.
		
			
				
	
	
		
			135 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			135 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* clock_gettime -- Get the current time from a POSIX clockid_t.  Unix version.
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   Copyright (C) 1999-2004, 2005 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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   The GNU C Library is free software; you can redistribute it and/or
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   modify it under the terms of the GNU Lesser General Public
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   License as published by the Free Software Foundation; either
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   version 2.1 of the License, or (at your option) any later version.
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   The GNU C Library is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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   Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public
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   License along with the GNU C Library; if not, write to the Free
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   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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   02111-1307 USA.  */
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#include <errno.h>
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#include <stdint.h>
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#include <time.h>
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#include <sys/time.h>
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#include <libc-internal.h>
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#include <ldsodefs.h>
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#if HP_TIMING_AVAIL
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/* Clock frequency of the processor.  We make it a 64-bit variable
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   because some jokers are already playing with processors with more
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   than 4GHz.  */
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static hp_timing_t freq;
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/* This function is defined in the thread library.  */
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extern int __pthread_clock_gettime (clockid_t clock_id, hp_timing_t freq,
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				    struct timespec *tp)
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     __attribute__ ((__weak__));
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static int
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hp_timing_gettime (clockid_t clock_id, struct timespec *tp)
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{
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  hp_timing_t tsc;
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  if (__builtin_expect (freq == 0, 0))
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    {
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      /* This can only happen if we haven't initialized the `freq'
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	 variable yet.  Do this now. We don't have to protect this
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	 code against multiple execution since all of them should
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	 lead to the same result.  */
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      freq = __get_clockfreq ();
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      if (__builtin_expect (freq == 0, 0))
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	/* Something went wrong.  */
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	return -1;
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    }
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  if (clock_id != CLOCK_PROCESS_CPUTIME_ID
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      && __pthread_clock_gettime != NULL)
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    return __pthread_clock_gettime (clock_id, freq, tp);
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  /* Get the current counter.  */
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  HP_TIMING_NOW (tsc);
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  /* Compute the offset since the start time of the process.  */
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  tsc -= GL(dl_cpuclock_offset);
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  /* Compute the seconds.  */
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  tp->tv_sec = tsc / freq;
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  /* And the nanoseconds.  This computation should be stable until
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     we get machines with about 16GHz frequency.  */
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  tp->tv_nsec = ((tsc % freq) * UINT64_C (1000000000)) / freq;
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  return 0;
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}
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#endif
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static inline int
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realtime_gettime (struct timespec *tp)
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{
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  struct timeval tv;
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  int retval = gettimeofday (&tv, NULL);
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  if (retval == 0)
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    /* Convert into `timespec'.  */
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    TIMEVAL_TO_TIMESPEC (&tv, tp);
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  return retval;
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}
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/* Get current value of CLOCK and store it in TP.  */
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int
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clock_gettime (clockid_t clock_id, struct timespec *tp)
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{
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  int retval = -1;
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  struct timeval tv;
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  switch (clock_id)
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    {
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#ifdef SYSDEP_GETTIME
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      SYSDEP_GETTIME;
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#endif
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#ifndef HANDLED_REALTIME
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    case CLOCK_REALTIME:
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      retval = gettimeofday (&tv, NULL);
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      if (retval == 0)
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	TIMEVAL_TO_TIMESPEC (&tv, tp);
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      break;
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#endif
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    default:
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#ifdef SYSDEP_GETTIME_CPU
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      SYSDEP_GETTIME_CPU;
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#endif
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#if HP_TIMING_AVAIL
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      if ((clock_id & ((1 << CLOCK_IDFIELD_SIZE) - 1))
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	  == CLOCK_THREAD_CPUTIME_ID)
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	retval = hp_timing_gettime (clock_id, tp);
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      else
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#endif
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	__set_errno (EINVAL);
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      break;
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#if HP_TIMING_AVAIL && !defined HANDLED_CPUTIME
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    case CLOCK_PROCESS_CPUTIME_ID:
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      retval = hp_timing_gettime (clock_id, tp);
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      break;
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#endif
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    }
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  return retval;
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}
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librt_hidden_def (clock_gettime)
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