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. 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/types.h>
  47 #include <sys/time.h>
  48 #include <sys/resource.h>
  49
  50 #include <err.h>
  51 #include <errno.h>
  52 #include <limits.h>
  53 #include <pwd.h>
  54 #include <stdio.h>
  55 #include <stdlib.h>
  56 #include <string.h>
  57
  58 static int      donice(int, int, int, int);
  59 static int      getnum(const char *, const char *, int *);
  60 static void     usage(void);
  61
  62 /*
  63  * Change the priority (nice) of processes
  64  * or groups of processes which are already
  65  * running.
  66  */
  67 int
  68 main(int argc, char *argv[])
  69 {
  70         struct passwd *pwd;
  71         int errs, incr, prio, which, who;
  72         int delim;
  73         int priflag;
  74
  75         errs = 0;
  76         incr = 0;
  77         which = PRIO_PROCESS;
  78         who = 0;
  79         argc--, argv++;
  80         if (argc < 2)
  81                 usage();
  82         delim = 0;
  83         priflag = 0;
  84
  85         /* incrementing priflag here ensures we only process
  86            the single priority arg if it is the very first arg */
  87         for (; argc > 0; argc--, argv++, priflag++) {
  88           /* once we've seen -- , don't process anymore switches */
  89           if (0 == delim) {
  90             /* -n must immediately be followed by the incremental
  91                priority */
  92             if (strcmp(*argv, "-n") == 0) {
  93               incr = 1;
  94               argc--, argv++;
  95               if (getnum("priority", *argv, &prio))
  96                 return (1);
  97               continue;
  98             }
  99                 if (strcmp(*argv, "-g") == 0) {
 100                         which = PRIO_PGRP;
 101                         continue;
 102                 }
 103                 if (strcmp(*argv, "-u") == 0) {
 104                         which = PRIO_USER;
 105                         continue;
 106                 }
 107                 if (strcmp(*argv, "-p") == 0) {
 108                         which = PRIO_PROCESS;
 109                         continue;
 110                 }
 111                 if (strcmp(*argv, "--") == 0) {
 112                         delim = 1;
 113                         continue;
 114                 }
 115                 if (0 == priflag) {
 116                 /* if very first switch/arg and we've made it to
 117                    here, this must be the priority */
 118                   if (getnum("priority", *argv, &prio)) {
 119                   return(1);
 120                   }
 121                 continue;
 122                 }
 123           }
 124                 if (which == PRIO_USER) {
 125                         if ((pwd = getpwnam(*argv)) != NULL)
 126                                 who = pwd->pw_uid;
 127                         else if (getnum("uid", *argv, &who)) {
 128                                 errs++;
 129                                 continue;
 130                         } else if (who < 0) {
 131                                 warnx("%s: bad value", *argv);
 132                                 errs++;
 133                                 continue;
 134                         }
 135                 } else {
 136                         if (getnum("pid", *argv, &who)) {
 137                                 errs++;
 138                                 continue;
 139                         }
 140                         if (who < 0) {
 141                                 warnx("%s: bad value", *argv);
 142                                 errs++;
 143                                 continue;
 144                         }
 145                 }
 146                 errs += donice(which, who, prio, incr);
 147         }
 148         exit(errs != 0);
 149 }
 150
 151 static int
 152 donice(int which, int who, int prio, int incr)
 153 {
 154         int oldprio;
 155
 156         errno = 0;
 157         oldprio = getpriority(which, who);
 158         if (oldprio == -1 && errno) {
 159                 warn("%d: getpriority", who);
 160                 return (1);
 161         }
 162         if (incr)
 163                 prio = oldprio + prio;
 164         if (prio > PRIO_MAX)
 165                 prio = PRIO_MAX;
 166         if (prio < PRIO_MIN)
 167                 prio = PRIO_MIN;
 168         if (setpriority(which, who, prio) < 0) {
 169                 warn("%d: setpriority", who);
 170                 return (1);
 171         }
 172         return (0);
 173 }
 174
 175 static int
 176 getnum(const char *com, const char *str, int *val)
 177 {
 178         long v;
 179         char *ep;
 180
 181         errno = 0;
 182         v = strtol(str, &ep, 10);
 183         if (v < INT_MIN || v > INT_MAX || errno == ERANGE) {
 184                 warnx("%s argument %s is out of range.", com, str);
 185                 return (1);
 186         }
 187         if (ep == str || *ep != '\0' || errno != 0) {
 188                 warnx("Bad %s argument: %s.", com, str);
 189                 return (1);
 190         }
 191
 192         *val = (int)v;
 193         return (0);
 194 }
 195
 196 static void
 197 usage()
 198 {
 199         fprintf(stderr, "%s\n%s\n",
 200 "usage: renice priority     [[-p] pid ...] [[-g] pgrp ...] [[-u] user ...]",
 201 "       renice -n increment [[-p] pid ...] [[-g] pgrp ...] [[-u] user ...]");
 202         exit(1);
 203 }