1/* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30#if defined(LIBC_SCCS) && !defined(lint) 31static char sccsid[] = "@(#)nice.c 8.1 (Berkeley) 6/4/93"; 32#endif /* LIBC_SCCS and not lint */ 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: src/lib/libc/gen/nice.c,v 1.4 2007/01/09 00:27:54 imp Exp $"); 35 36#include <sys/types.h> 37#include <sys/time.h> 38#include <sys/resource.h> 39#include <errno.h> 40#include <unistd.h> 41#if __DARWIN_UNIX03 42#include <limits.h> 43#endif /* __DARWIN_UNIX03 */ 44/* 45 * Backwards compatible nice. 46 */ 47int 48nice(incr) 49 int incr; 50{ 51 int prio, rv; 52 53 errno = 0; 54 prio = getpriority(PRIO_PROCESS, 0); 55 if (prio == -1 && errno) 56 return (-1); 57#if __DARWIN_UNIX03 58 if (prio + incr > NZERO-1) 59 incr = NZERO-1-prio; 60#endif /* __DARWIN_UNIX03 */ 61 rv = setpriority(PRIO_PROCESS, 0, prio + incr); 62 if (rv == -1 && errno == EACCES) 63 errno = EPERM; 64 return (rv == -1) ? rv : getpriority(PRIO_PROCESS, 0); 65} 66