libc/gen/getloadavg.c

1.1      cgd /*-
1.1      cgd  * Copyright (c) 1989 The Regents of the University of California.
1.1      cgd  * All rights reserved.
1.1      cgd  *
1.1      cgd  * Redistribution and use in source and binary forms, with or without
1.1      cgd  * modification, are permitted provided that the following conditions
1.1      cgd  * are met:
1.1      cgd  * 1. Redistributions of source code must retain the above copyright
1.1      cgd  *    notice, this list of conditions and the following disclaimer.
1.1      cgd  * 2. Redistributions in binary form must reproduce the above copyright
1.1      cgd  *    notice, this list of conditions and the following disclaimer in the
1.1      cgd  *    documentation and/or other materials provided with the distribution.
1.1      cgd  * 3. All advertising materials mentioning features or use of this software
1.1      cgd  *    must display the following acknowledgement:
1.1      cgd  *	This product includes software developed by the University of
1.1      cgd  *	California, Berkeley and its contributors.
1.1      cgd  * 4. Neither the name of the University nor the names of its contributors
1.1      cgd  *    may be used to endorse or promote products derived from this software
1.1      cgd  *    without specific prior written permission.
1.1      cgd  *
1.1      cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
1.1      cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.1      cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.1      cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
1.1      cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
1.1      cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
1.1      cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1.1      cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
1.1      cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
1.1      cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
1.1      cgd  * SUCH DAMAGE.
1.1      cgd  */
1.1      cgd
1.1      cgd #if defined(LIBC_SCCS) && !defined(lint)
1.2  mycroft /*static char sccsid[] = "from: @(#)getloadavg.c	6.2 (Berkeley) 6/29/90";*/
1.3      cgd static char rcsid[] = "$Id: getloadavg.c,v 1.3 1994/01/28 04:49:27 cgd Exp $";
1.1      cgd #endif /* LIBC_SCCS and not lint */
1.1      cgd
1.1      cgd #include <sys/types.h>
1.3      cgd #include <sys/time.h>
1.3      cgd #include <sys/resource.h>
1.3      cgd #include <sys/kinfo.h>
1.1      cgd
1.1      cgd /*
1.1      cgd  *  getloadavg() -- Get system load averages.
1.1      cgd  *
1.1      cgd  *  Put `nelem' samples into `loadavg' array.
1.1      cgd  *  Return number of samples retrieved, or -1 on error.
1.1      cgd  */
1.1      cgd getloadavg(loadavg, nelem)
1.1      cgd 	double loadavg[];
1.1      cgd 	int nelem;
1.1      cgd {
1.3      cgd 	int needed, err, i;
1.3      cgd 	struct loadavg averunnable;
1.3      cgd
1.3      cgd 	needed = getkerninfo(KINFO_LOADAVG, NULL, NULL, 0);
1.3      cgd 	if (needed != sizeof(struct loadavg))
1.3      cgd 		return -1;
1.1      cgd
1.3      cgd 	err = getkerninfo(KINFO_LOADAVG, &averunnable, &needed, 0);
1.3      cgd 	if (err != 0 || needed != sizeof(struct loadavg))
1.3      cgd 		return -1;
1.3      cgd
1.3      cgd 	if (nelem > 3)
1.3      cgd 		nelem = 3;
1.1      cgd 	for (i = 0; i < nelem; i++)
1.3      cgd 		loadavg[i] = (double) averunnable.ldavg[i] / averunnable.fscale;
1.3      cgd 	return nelem;
1.1      cgd }