usr.bin/renice/renice.c

   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. 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  * @(#) Copyright (c) 1983, 1989, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)renice.c 8.1 (Berkeley) 6/9/93
  31  * $FreeBSD: src/usr.bin/renice/renice.c,v 1.4.2.3 2002/06/17 23:58:46 tjr Exp $
  32  * $DragonFly: src/usr.bin/renice/renice.c,v 1.5 2008/10/16 01:52:33 swildner Exp $
  33  */
  34
  35 #include <sys/time.h>
  36 #include <sys/resource.h>
  37
  38 #include <err.h>
  39 #include <errno.h>
  40 #include <limits.h>
  41 #include <pwd.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45
  46 static int      donice(int, int, int, int);
  47 static int      getnum(const char *, const char *, int *);
  48 static void     usage(void);
  49
  50 /*
  51  * Change the priority (nice) of processes
  52  * or groups of processes which are already
  53  * running.
  54  */
  55 int
  56 main(int argc, char *argv[])
  57 {
  58         struct passwd *pwd;
  59         int errs, incr, prio, which, who;
  60
  61         errs = 0;
  62         incr = 0;
  63         which = PRIO_PROCESS;
  64         who = 0;
  65         argc--, argv++;
  66         if (argc < 2)
  67                 usage();
  68         if (strcmp(*argv, "-n") == 0) {
  69                 incr = 1;
  70                 argc--, argv++;
  71                 if (argc < 2)
  72                         usage();
  73         }
  74         if (getnum("priority", *argv, &prio))
  75                 return (1);
  76         argc--, argv++;
  77         for (; argc > 0; argc--, argv++) {
  78                 if (strcmp(*argv, "-g") == 0) {
  79                         which = PRIO_PGRP;
  80                         continue;
  81                 }
  82                 if (strcmp(*argv, "-u") == 0) {
  83                         which = PRIO_USER;
  84                         continue;
  85                 }
  86                 if (strcmp(*argv, "-p") == 0) {
  87                         which = PRIO_PROCESS;
  88                         continue;
  89                 }
  90                 if (which == PRIO_USER) {
  91                         if ((pwd = getpwnam(*argv)) != NULL)
  92                                 who = pwd->pw_uid;
  93                         else if (getnum("uid", *argv, &who)) {
  94                                 errs++;
  95                                 continue;
  96                         } else if (who < 0) {
  97                                 warnx("%s: bad value", *argv);
  98                                 errs++;
  99                                 continue;
 100                         }
 101                 } else {
 102                         if (getnum("pid", *argv, &who)) {
 103                                 errs++;
 104                                 continue;
 105                         }
 106                         if (who < 0) {
 107                                 warnx("%s: bad value", *argv);
 108                                 errs++;
 109                                 continue;
 110                         }
 111                 }
 112                 errs += donice(which, who, prio, incr);
 113         }
 114         exit(errs != 0);
 115 }
 116
 117 static int
 118 donice(int which, int who, int prio, int incr)
 119 {
 120         int oldprio;
 121
 122         errno = 0;
 123         oldprio = getpriority(which, who);
 124         if (oldprio == -1 && errno) {
 125                 warn("%d: getpriority", who);
 126                 return (1);
 127         }
 128         if (incr)
 129                 prio = oldprio + prio;
 130         if (prio > PRIO_MAX)
 131                 prio = PRIO_MAX;
 132         if (prio < PRIO_MIN)
 133                 prio = PRIO_MIN;
 134         if (setpriority(which, who, prio) < 0) {
 135                 warn("%d: setpriority", who);
 136                 return (1);
 137         }
 138         fprintf(stderr, "%d: old priority %d, new priority %d\n", who,
 139             oldprio, prio);
 140         return (0);
 141 }
 142
 143 static int
 144 getnum(const char *com, const char *str, int *val)
 145 {
 146         long v;
 147         char *ep;
 148
 149         errno = 0;
 150         v = strtol(str, &ep, 10);
 151         if (v < INT_MIN || v > INT_MAX || errno == ERANGE) {
 152                 warnx("%s argument %s is out of range.", com, str);
 153                 return (1);
 154         }
 155         if (ep == str || *ep != '\0') {
 156                 warnx("Bad %s argument: %s.", com, str);
 157                 return (1);
 158         }
 159
 160         *val = (int)v;
 161         return (0);
 162 }
 163
 164 static void
 165 usage(void)
 166 {
 167         fprintf(stderr, "%s\n%s\n",
 168 "usage: renice [priority | [-n incr]] [[-p] pid ...] [[-g] pgrp ...]",
 169 "              [[-u] user ...]");
 170         exit(1);
 171 }