/*

 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")

 *

 * This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/.

 *

 * See the COPYRIGHT file distributed with this work for additional

 * information regarding copyright ownership.

 */

#include <config.h>

#include <isc/os.h>

#ifdef HAVE_SYSCONF

#include <unistd.h>

#ifndef __hpux

static inline long

sysconf_ncpus(void) {

#if defined(_SC_NPROCESSORS_ONLN)

	return sysconf((_SC_NPROCESSORS_ONLN));

#elif defined(_SC_NPROC_ONLN)

	return sysconf((_SC_NPROC_ONLN));

#else

	return (0);

#endif

}

#endif

#endif /* HAVE_SYSCONF */

#ifdef __hpux

#include <sys/pstat.h>

static inline int

hpux_ncpus(void) {

	struct pst_dynamic psd;

	if (pstat_getdynamic(&psd, sizeof(psd), 1, 0) != -1)

		return (psd.psd_proc_cnt);

	else

		return (0);

}

#endif /* __hpux */

#if defined(HAVE_SYS_SYSCTL_H) && defined(HAVE_SYSCTLBYNAME)

#include <sys/types.h>  /* for FreeBSD */

#include <sys/param.h>  /* for NetBSD */

#include <sys/sysctl.h>

static int

sysctl_ncpus(void) {

	int ncpu, result;

	size_t len;

	len = sizeof(ncpu);

	result = sysctlbyname("hw.ncpu", &ncpu, &len , 0, 0);

	if (result != -1)

		return (ncpu);

	return (0);

}

#endif

unsigned int

isc_os_ncpus(void) {

	long ncpus = 0;

#ifdef __hpux

	ncpus = hpux_ncpus();

#elif defined(HAVE_SYSCONF)

	ncpus = sysconf_ncpus();

#endif

#if defined(HAVE_SYS_SYSCTL_H) && defined(HAVE_SYSCTLBYNAME)

	if (ncpus <= 0)

		ncpus = sysctl_ncpus();

#endif

	if (ncpus <= 0)

		ncpus = 1;

	return ((unsigned int)ncpus);

}