usr.bin/renice/renice.c

   1 /*      $NetBSD: renice.c,v 1.17 2007/12/15 19:44:52 perry 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\
  35  The Regents of the University of California.  All rights reserved.");
  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 1.17 2007/12/15 19:44:52 perry 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 #include <sysexits.h>
  53
  54 static int      getnum(const char *, const char *, int *);
  55 static int      donice(int, id_t, int, int);
  56 static void     usage(void) __dead;
  57
  58 /*
  59  * Change the priority (nice) of processes
  60  * or groups of processes which are already
  61  * running.
  62  */
  63 int
  64 main(int argc, char **argv)
  65 {
  66         int which = PRIO_PROCESS;
  67         int prio, errs = 0, incr = 0;
  68         id_t who = 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                                 errs++;
 101                                 continue;
 102                         }
 103                         who = (id_t)pwd->pw_uid;
 104                 } else {
 105                         int twho;
 106                         if (getnum("pid", *argv, &twho)) {
 107                                 errs++;
 108                                 continue;
 109                         }
 110                         if (twho < 0) {
 111                                 warnx("%s: bad value", *argv);
 112                                 errs++;
 113                                 continue;
 114                         }
 115                         who = (id_t)twho;
 116                 }
 117                 errs += donice(which, who, prio, incr);
 118         }
 119         return errs == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
 120 }
 121
 122 static int
 123 getnum(const char *com, const char *str, int *val)
 124 {
 125         long v;
 126         char *ep;
 127
 128         errno = 0;
 129         v = strtol(str, &ep, 0);
 130
 131         if (*ep) {
 132                 warnx("Bad %s argument: %s", com, str);
 133                 return 1;
 134         }
 135         if ((v == LONG_MIN || v == LONG_MAX) && errno == ERANGE) {
 136                 warn("Invalid %s argument: %s", com, str);
 137                 return 1;
 138         }
 139
 140         *val = (int)v;
 141         return 0;
 142 }
 143
 144 static int
 145 donice(int which, id_t who, int prio, int incr)
 146 {
 147         int oldprio;
 148
 149         errno = 0;
 150         if ((oldprio = getpriority(which, who)) == -1 && errno != 0) {
 151                 warn("%d: getpriority", who);
 152                 return 1;
 153         }
 154
 155         if (incr)
 156                 prio = oldprio + prio;
 157
 158         if (prio > PRIO_MAX)
 159                 prio = PRIO_MAX;
 160         if (prio < PRIO_MIN)
 161                 prio = PRIO_MIN;
 162
 163         if (setpriority(which, who, prio) == -1) {
 164                 warn("%d: setpriority", who);
 165                 return 1;
 166         }
 167         (void)printf("%d: old priority %d, new priority %d\n",
 168             who, oldprio, prio);
 169         return 0;
 170 }
 171
 172 static void
 173 usage(void)
 174 {
 175
 176         (void)fprintf(stderr, "Usage: %s [<priority> | -n <incr>] ",
 177             getprogname());
 178         (void)fprintf(stderr, "[[-p] <pids>...] [-g <pgrp>...] ");
 179         (void)fprintf(stderr, "[-u <user>...]\n");
 180         exit(1);
 181 }