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Diffstat (limited to 'sysdeps/posix/clock_getres.c')
-rw-r--r--sysdeps/posix/clock_getres.c111
1 files changed, 60 insertions, 51 deletions
diff --git a/sysdeps/posix/clock_getres.c b/sysdeps/posix/clock_getres.c
index a2d4666..f4dc21f 100644
--- a/sysdeps/posix/clock_getres.c
+++ b/sysdeps/posix/clock_getres.c
@@ -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
}