xref: /freebsd/usr.bin/renice/renice.c (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
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
35 static 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 #if 0
41 #ifndef lint
42 static char sccsid[] = "@(#)renice.c	8.1 (Berkeley) 6/9/93";
43 #endif /* not lint */
44 #endif
45 
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 #include <sys/types.h>
50 #include <sys/time.h>
51 #include <sys/resource.h>
52 
53 #include <err.h>
54 #include <errno.h>
55 #include <limits.h>
56 #include <pwd.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 
61 static int	donice(int, int, int, int);
62 static int	getnum(const char *, const char *, int *);
63 static void	usage(void);
64 
65 /*
66  * Change the priority (nice) of processes
67  * or groups of processes which are already
68  * running.
69  */
70 int
71 main(int argc, char *argv[])
72 {
73 	struct passwd *pwd;
74 	int errs, incr, prio, which, who;
75 
76 	errs = 0;
77 	incr = 0;
78 	which = PRIO_PROCESS;
79 	who = 0;
80 	argc--, argv++;
81 	if (argc < 2)
82 		usage();
83 	if (strcmp(*argv, "-n") == 0) {
84 		incr = 1;
85 		argc--, argv++;
86 		if (argc < 2)
87 			usage();
88 	}
89 	if (getnum("priority", *argv, &prio))
90 		return (1);
91 	argc--, argv++;
92 	for (; argc > 0; argc--, argv++) {
93 		if (strcmp(*argv, "-g") == 0) {
94 			which = PRIO_PGRP;
95 			continue;
96 		}
97 		if (strcmp(*argv, "-u") == 0) {
98 			which = PRIO_USER;
99 			continue;
100 		}
101 		if (strcmp(*argv, "-p") == 0) {
102 			which = PRIO_PROCESS;
103 			continue;
104 		}
105 		if (which == PRIO_USER) {
106 			if ((pwd = getpwnam(*argv)) != NULL)
107 				who = pwd->pw_uid;
108 			else if (getnum("uid", *argv, &who)) {
109 				errs++;
110 				continue;
111 			} else if (who < 0) {
112 				warnx("%s: bad value", *argv);
113 				errs++;
114 				continue;
115 			}
116 		} else {
117 			if (getnum("pid", *argv, &who)) {
118 				errs++;
119 				continue;
120 			}
121 			if (who < 0) {
122 				warnx("%s: bad value", *argv);
123 				errs++;
124 				continue;
125 			}
126 		}
127 		errs += donice(which, who, prio, incr);
128 	}
129 	exit(errs != 0);
130 }
131 
132 static int
133 donice(int which, int who, int prio, int incr)
134 {
135 	int oldprio;
136 
137 	errno = 0;
138 	oldprio = getpriority(which, who);
139 	if (oldprio == -1 && errno) {
140 		warn("%d: getpriority", who);
141 		return (1);
142 	}
143 	if (incr)
144 		prio = oldprio + prio;
145 	if (prio > PRIO_MAX)
146 		prio = PRIO_MAX;
147 	if (prio < PRIO_MIN)
148 		prio = PRIO_MIN;
149 	if (setpriority(which, who, prio) < 0) {
150 		warn("%d: setpriority", who);
151 		return (1);
152 	}
153 	fprintf(stderr, "%d: old priority %d, new priority %d\n", who,
154 	    oldprio, prio);
155 	return (0);
156 }
157 
158 static int
159 getnum(const char *com, const char *str, int *val)
160 {
161 	long v;
162 	char *ep;
163 
164 	errno = 0;
165 	v = strtol(str, &ep, 10);
166 	if (v < INT_MIN || v > INT_MAX || errno == ERANGE) {
167 		warnx("%s argument %s is out of range.", com, str);
168 		return (1);
169 	}
170 	if (ep == str || *ep != '\0' || errno != 0) {
171 		warnx("Bad %s argument: %s.", com, str);
172 		return (1);
173 	}
174 
175 	*val = (int)v;
176 	return (0);
177 }
178 
179 static void
180 usage()
181 {
182 	fprintf(stderr, "%s\n%s\n",
183 "usage: renice priority     [[-p] pid ...] [[-g] pgrp ...] [[-u] user ...]",
184 "       renice -n increment [[-p] pid ...] [[-g] pgrp ...] [[-u] user ...]");
185 	exit(1);
186 }
187