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89fb683558
__clock_gettime and other __clock_* functions could result in an extra PLT reference within libc.so if it actually gets used. None of the code currently uses them, which is why this probably went unnoticed.
137 lines
3.5 KiB
C
137 lines
3.5 KiB
C
/* clock_gettime -- Get the current time from a POSIX clockid_t. Unix version.
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Copyright (C) 1999-2013 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, see
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<http://www.gnu.org/licenses/>. */
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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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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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{
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struct timeval tv;
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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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}
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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 (clock_id, tp);
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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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weak_alias (__clock_gettime, clock_gettime)
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libc_hidden_def (__clock_gettime)
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