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renice.c revision 1.14 
      1 /*	$NetBSD: renice.c,v 1.14 2003/10/21 02:24:08 fvdl Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1983, 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 __COPYRIGHT("@(#) Copyright (c) 1983, 1989, 1993\n\
     35 	The Regents of the University of California.  All rights reserved.\n");
     36 #endif /* not lint */
     37 
     38 #ifndef lint
     39 /*static char sccsid[] = "from: @(#)renice.c	8.1 (Berkeley) 6/9/93";*/
     40 __RCSID("$NetBSD: renice.c,v 1.14 2003/10/21 02:24:08 fvdl Exp $");
     41 #endif /* not lint */
     42 
     43 #include <sys/resource.h>
     44 
     45 #include <err.h>
     46 #include <errno.h>
     47 #include <limits.h>
     48 #include <pwd.h>
     49 #include <stdio.h>
     50 #include <stdlib.h>
     51 #include <string.h>
     52 
     53 static int	getnum(const char *, const char *, int *);
     54 static int	donice(int, int, int, int);
     55 static void	usage(void) __attribute__((__noreturn__));
     56 
     57 int	main(int, char **);
     58 
     59 /*
     60  * Change the priority (nice) of processes
     61  * or groups of processes which are already
     62  * running.
     63  */
     64 int
     65 main(int argc, char **argv)
     66 {
     67 	int which = PRIO_PROCESS;
     68 	int who = 0, prio, errs = 0, incr = 0;
     69 
     70 	argc--, argv++;
     71 	if (argc < 2)
     72 		usage();
     73 	if (strcmp(*argv, "-n") == 0) {
     74 		incr = 1;
     75 		argc--, argv++;
     76 		if (argc == 0)
     77 			usage();
     78 	}
     79 	if (getnum("priority", *argv, &prio))
     80 		return 1;
     81 	argc--, argv++;
     82 	for (; argc > 0; argc--, argv++) {
     83 		if (strcmp(*argv, "-g") == 0) {
     84 			which = PRIO_PGRP;
     85 			continue;
     86 		}
     87 		if (strcmp(*argv, "-u") == 0) {
     88 			which = PRIO_USER;
     89 			continue;
     90 		}
     91 		if (strcmp(*argv, "-p") == 0) {
     92 			which = PRIO_PROCESS;
     93 			continue;
     94 		}
     95 		if (which == PRIO_USER) {
     96 			struct passwd *pwd = getpwnam(*argv);
     97 
     98 			if (pwd == NULL) {
     99 				warnx("%s: unknown user", *argv);
    100 				continue;
    101 			}
    102 			who = pwd->pw_uid;
    103 		} else {
    104 			if (getnum("pid", *argv, &who))
    105 				continue;
    106 			if (who < 0) {
    107 				warnx("%s: bad value", *argv);
    108 				continue;
    109 			}
    110 		}
    111 		errs += donice(which, who, prio, incr);
    112 	}
    113 	exit(errs != 0);
    114 }
    115 
    116 static int
    117 getnum(const char *com, const char *str, int *val)
    118 {
    119 	long v;
    120 	char *ep;
    121 
    122 	errno = 0;
    123 	v = strtol(str, &ep, 0);
    124 
    125 	if (*ep) {
    126 		warnx("Bad %s argument: %s", com, str);
    127 		return 1;
    128 	}
    129 	if ((v == LONG_MIN || v == LONG_MAX) && errno == ERANGE) {
    130 		warn("Invalid %s argument: %s", com, str);
    131 		return 1;
    132 	}
    133 
    134 	*val = (int)v;
    135 	return 0;
    136 }
    137 
    138 static int
    139 donice(int which, int who, int prio, int incr)
    140 {
    141 	int oldprio;
    142 
    143 	errno = 0;
    144 	if ((oldprio = getpriority(which, who)) == -1 && errno != 0) {
    145 		warn("%d: getpriority", who);
    146 		return (1);
    147 	}
    148 
    149 	if (incr)
    150 		prio = oldprio + prio;
    151 
    152 	if (prio > PRIO_MAX)
    153 		prio = PRIO_MAX;
    154 	if (prio < PRIO_MIN)
    155 		prio = PRIO_MIN;
    156 
    157 	if (setpriority(which, who, prio) == -1) {
    158 		warn("%d: setpriority", who);
    159 		return (1);
    160 	}
    161 	printf("%d: old priority %d, new priority %d\n", who, oldprio, prio);
    162 	return (0);
    163 }
    164 
    165 static void
    166 usage(void)
    167 {
    168 
    169 	fprintf(stderr, "Usage: %s [<priority> | -n <incr>] ", getprogname());
    170 	fprintf(stderr, "[[-p] <pids>...] [-g <pgrp>...] ");
    171 	fprintf(stderr, "[-u <user>...]\n");
    172 	exit(1);
    173 }
    174