#
# SYNOPSIS
#
# TUKLIB_CPUCORES
#
# DESCRIPTION
#
# Check how to find out the number of available CPU cores in the system.
# This information is used by tuklib_cpucores.c.
#
# Currently this supports sysctl() (BSDs, OS/2) and sysconf() (GNU/Linux,
# Solaris, Cygwin).
#
# COPYING
#
# Author: Lasse Collin
#
# This file has been put into the public domain.
# You can do whatever you want with this file.
#
AC_DEFUN_ONCE([TUKLIB_CPUCORES], [
AC_REQUIRE([TUKLIB_COMMON])
# sys/param.h might be needed by sys/sysctl.h.
AC_CHECK_HEADERS([sys/param.h])
AC_CACHE_CHECK([how to detect the number of available CPU cores],
[tuklib_cv_cpucores_method], [
# Look for sysctl() solution first, because on OS/2, both sysconf()
# and sysctl() pass the tests in this file, but only sysctl()
# actually works.
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#include <sys/types.h>
#ifdef HAVE_SYS_PARAM_H
# include <sys/param.h>
#endif
#include <sys/sysctl.h>
int
main(void)
{
int name[2] = { CTL_HW, HW_NCPU };
int cpus;
size_t cpus_size = sizeof(cpus);
sysctl(name, 2, &cpus, &cpus_size, NULL, 0);
return 0;
}
]])], [tuklib_cv_cpucores_method=sysctl], [
AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
#include <unistd.h>
int
main(void)
{
long i;
i = sysconf(_SC_NPROCESSORS_ONLN);
return 0;
}
]])], [
tuklib_cv_cpucores_method=sysconf
], [
tuklib_cv_cpucores_method=unknown
])])])
case $tuklib_cv_cpucores_method in
sysctl)
AC_DEFINE([TUKLIB_CPUCORES_SYSCTL], [1],
[Define to 1 if the number of available CPU cores
can be detected with sysctl().])
;;
sysconf)
AC_DEFINE([TUKLIB_CPUCORES_SYSCONF], [1],
[Define to 1 if the number of available CPU cores
can be detected with sysconf(_SC_NPROCESSORS_ONLN).])
;;
esac
])dnl
