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2.5-18.1

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This commit is contained in:
Jakub Jelinek
2007-07-12 18:26:36 +00:00
parent 7d58530341
commit 0ecb606cb6
6215 changed files with 494638 additions and 305010 deletions
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111
sysdeps/posix/clock_getres.c
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@ -1,4 +1,5 @@
/* Copyright (C) 1999, 2000, 2001, 2003 Free Software Foundation, Inc.
/* clock_getres -- Get the resolution of a POSIX clockid_t.
Copyright (C) 1999, 2000, 2001, 2003, 2004 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
@ -24,11 +25,55 @@
#include <libc-internal.h>
#if HP_TIMING_AVAIL && !defined HANDLED_CPUTIME
/* Clock frequency of the processor. */
static long int nsec;
#if HP_TIMING_AVAIL
static long int nsec; /* Clock frequency of the processor. */
static inline int
hp_timing_getres (struct timespec *res)
{
if (__builtin_expect (nsec == 0, 0))
{
hp_timing_t freq;
/* This can only happen if we haven't initialized the `nsec'
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. */
return -1;
nsec = MAX (UINT64_C (1000000000) / freq, 1);
}
/* Fill in the values.
The seconds are always zero (unless we have a 1Hz machine). */
res->tv_sec = 0;
res->tv_nsec = nsec;
return 0;
}
#endif
static inline int
realtime_getres (struct timespec *res)
{
long int clk_tck = sysconf (_SC_CLK_TCK);
if (__builtin_expect (clk_tck != -1, 1))
{
/* This implementation assumes that the realtime clock has a
resolution higher than 1 second. This is the case for any
reasonable implementation. */
res->tv_sec = 0;
res->tv_nsec = 1000000000 / clk_tck;
return 0;
}
return -1;
}
/* Get resolution of clock. */
int
@ -38,69 +83,33 @@ clock_getres (clockid_t clock_id, struct timespec *res)
switch (clock_id)
{
#define HANDLE_REALTIME \
do { \
long int clk_tck = sysconf (_SC_CLK_TCK); \
\
if (__builtin_expect (clk_tck != -1, 1)) \
{ \
/* This implementation assumes that the realtime clock has a \
resolution higher than 1 second. This is the case for any \
reasonable implementation. */ \
res->tv_sec = 0; \
res->tv_nsec = 1000000000 / clk_tck; \
\
retval = 0; \
} \
} while (0)
#ifdef SYSDEP_GETRES
SYSDEP_GETRES;
#endif
#ifndef HANDLED_REALTIME
case CLOCK_REALTIME:
HANDLE_REALTIME;
retval = realtime_getres (res);
break;
#endif /* handled REALTIME */
default:
#ifdef SYSDEP_GETRES_CPU
SYSDEP_GETRES_CPU;
#endif
#if HP_TIMING_AVAIL
if ((clock_id & ((1 << CLOCK_IDFIELD_SIZE) - 1))
!= CLOCK_THREAD_CPUTIME_ID)
== CLOCK_THREAD_CPUTIME_ID)
retval = hp_timing_getres (res);
else
#endif
{
__set_errno (EINVAL);
break;
}
__set_errno (EINVAL);
break;
#if HP_TIMING_AVAIL && !defined HANDLED_CPUTIME
/* FALLTHROUGH. */
case CLOCK_PROCESS_CPUTIME_ID:
{
if (__builtin_expect (nsec == 0, 0))
{
hp_timing_t freq;
/* 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;
nsec = MAX (UINT64_C (1000000000) / freq, 1);
}
/* File in the values. The seconds are always zero (unless we
have a 1Hz machine). */
res->tv_sec = 0;
res->tv_nsec = nsec;
retval = 0;
}
case CLOCK_THREAD_CPUTIME_ID:
retval = hp_timing_getres (res);
break;
#endif
}