renice.c revision 96763 
1/*
2 * Copyright (c) 1983, 1989, 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 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1983, 1989, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "@(#)renice.c	8.1 (Berkeley) 6/9/93";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/usr.bin/renice/renice.c 96763 2002-05-16 23:44:11Z tjr $";
46#endif /* not lint */
47
48#include <sys/types.h>
49#include <sys/time.h>
50#include <sys/resource.h>
51
52#include <err.h>
53#include <errno.h>
54#include <limits.h>
55#include <pwd.h>
56#include <stdio.h>
57#include <stdlib.h>
58#include <string.h>
59
60static int	donice(int, int, int, int);
61static int	getnum(const char *, const char *, int *);
62static void	usage(void);
63
64/*
65 * Change the priority (nice) of processes
66 * or groups of processes which are already
67 * running.
68 */
69int
70main(int argc, char *argv[])
71{
72	struct passwd *pwd;
73	int errs, incr, prio, which, who;
74
75	errs = 0;
76	incr = 0;
77	which = PRIO_PROCESS;
78	who = 0;
79	argc--, argv++;
80	if (argc < 2)
81		usage();
82	if (strcmp(*argv, "-n") == 0) {
83		incr = 1;
84		argc--, argv++;
85		if (argc < 2)
86			usage();
87	}
88	if (getnum("priority", *argv, &prio))
89		return (1);
90	argc--, argv++;
91	for (; argc > 0; argc--, argv++) {
92		if (strcmp(*argv, "-g") == 0) {
93			which = PRIO_PGRP;
94			continue;
95		}
96		if (strcmp(*argv, "-u") == 0) {
97			which = PRIO_USER;
98			continue;
99		}
100		if (strcmp(*argv, "-p") == 0) {
101			which = PRIO_PROCESS;
102			continue;
103		}
104		if (which == PRIO_USER) {
105			if ((pwd = getpwnam(*argv)) != NULL)
106				who = pwd->pw_uid;
107			else if (getnum("uid", *argv, &who))
108				continue;
109			else if (who < 0) {
110				warnx("%s: bad value", *argv);
111				continue;
112			}
113		} else {
114			if (getnum("pid", *argv, &who))
115				continue;
116			if (who < 0) {
117				warnx("%s: bad value", *argv);
118				continue;
119			}
120		}
121		errs += donice(which, who, prio, incr);
122	}
123	exit(errs != 0);
124}
125
126static int
127donice(int which, int who, int prio, int incr)
128{
129	int oldprio;
130
131	errno = 0;
132	oldprio = getpriority(which, who);
133	if (oldprio == -1 && errno) {
134		warn("%d: getpriority", who);
135		return (1);
136	}
137	if (incr)
138		prio = oldprio + prio;
139	if (prio > PRIO_MAX)
140		prio = PRIO_MAX;
141	if (prio < PRIO_MIN)
142		prio = PRIO_MIN;
143	if (setpriority(which, who, prio) < 0) {
144		warn("%d: setpriority", who);
145		return (1);
146	}
147	fprintf(stderr, "%d: old priority %d, new priority %d\n", who,
148	    oldprio, prio);
149	return (0);
150}
151
152static int
153getnum(const char *com, const char *str, int *val)
154{
155	long v;
156	char *ep;
157
158	errno = 0;
159	v = strtol(str, &ep, NULL);
160	if (v < INT_MIN || v > INT_MAX || errno == ERANGE) {
161		warnx("%s argument %s is out of range.", com, str);
162		return (1);
163	}
164	if (ep == str || *ep != '\0' || errno != 0) {
165		warnx("Bad %s argument: %s.", com, str);
166		return (1);
167	}
168
169	*val = (int)v;
170	return (0);
171}
172
173static void
174usage()
175{
176	fprintf(stderr, "%s\n%s\n",
177"usage: renice [priority | [-n incr]] [ [ -p ] pids ] [ [ -g ] pgrps ]",
178"              [ [ -u ] users ]");
179	exit(1);
180}
181