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/* Copyright (C) 1999, 2000, 2001 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <stdint.h>
#include <time.h>
#include <sys/time.h>
#include <libc-internal.h>
#include <hp-timing.h>
#if HP_TIMING_AVAIL
/* Clock frequency of the processor. We make it a 64-bit variable
because some jokers are already playing with processors with more
than 4GHz. */
static hp_timing_t freq;
/* We need the starting time for the process. */
extern hp_timing_t _dl_cpuclock_offset;
/* This function is defined in the thread library. */
extern int __pthread_clock_gettime (hp_timing_t freq, struct timespec *tp)
__attribute__ ((__weak__));
#endif
/* Get current value of CLOCK and store it in TP. */
int
clock_gettime (clockid_t clock_id, struct timespec *tp)
{
struct timeval tv;
int retval = -1;
switch (clock_id)
{
case CLOCK_REALTIME:
retval = gettimeofday (&tv, NULL);
if (retval == 0)
/* Convert into `timespec'. */
TIMEVAL_TO_TIMESPEC (&tv, tp);
break;
#if HP_TIMING_AVAIL
case CLOCK_PROCESS_CPUTIME_ID:
case CLOCK_THREAD_CPUTIME_ID:
{
hp_timing_t tsc;
if (__builtin_expect (freq == 0, 0))
{
/* This can only happen if we haven't initialized the `freq'
variable yet. Do this now. We don't have to protect this
code against multiple execution since all of them should
lead to the same result. */
freq = __get_clockfreq ();
if (__builtin_expect (freq == 0, 0))
/* Something went wrong. */
break;
}
if (clock_id == CLOCK_THREAD_CPUTIME_ID
&& __pthread_clock_gettime != NULL)
{
retval = __pthread_clock_gettime (freq, tp);
break;
}
/* Get the current counter. */
HP_TIMING_NOW (tsc);
/* Compute the offset since the start time of the process. */
tsc -= _dl_cpuclock_offset;
/* Compute the seconds. */
tp->tv_sec = tsc / freq;
/* And the nanoseconds. This computation should be stable until
we get machines with about 16GHz frequency. */
tp->tv_nsec = ((tsc % freq) * UINT64_C (1000000000)) / freq;
retval = 0;
}
break;
#endif
default:
__set_errno (EINVAL);
break;
}
return retval;
}
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