usr.bin/nice/nice.c

   1 /*      $NetBSD: nice.c,v 1.15 2008/07/21 14:19:24 lukem Exp $  */
   2
   3 /*
   4  * Copyright (c) 1989 The Regents of the University of California.
   5  * 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) 1989\
  35  The Regents of the University of California.  All rights reserved.");
  36 #endif /* not lint */
  37
  38 #ifndef lint
  39 #if 0
  40 static char sccsid[] = "@(#)nice.c      5.4 (Berkeley) 6/1/90";
  41 #endif
  42 __RCSID("$NetBSD: nice.c,v 1.15 2008/07/21 14:19:24 lukem Exp $");
  43 #endif /* not lint */
  44
  45 #include <sys/time.h>
  46 #include <sys/resource.h>
  47
  48 #include <stdio.h>
  49 #include <stdlib.h>
  50 #include <string.h>
  51 #include <limits.h>
  52 #include <locale.h>
  53 #include <ctype.h>
  54 #include <errno.h>
  55 #include <err.h>
  56 #include <unistd.h>
  57
  58 #define DEFNICE 10
  59
  60 static void usage(void) __dead;
  61
  62 int
  63 main(int argc, char **argv)
  64 {
  65         char *ep;
  66         int niceness = DEFNICE;
  67         int c;
  68         long tmp;
  69
  70         setprogname(argv[0]);
  71         (void)setlocale(LC_ALL, "");
  72
  73         /* handle obsolete -number syntax */
  74         if (argc > 1 && argv[1][0] == '-' &&
  75             isdigit((unsigned char)argv[1][1])) {
  76                 niceness = atoi (argv[1] + 1);
  77                 argc--; argv++;
  78         }
  79
  80         while ((c = getopt (argc, argv, "n:")) != -1) {
  81                 switch (c) {
  82                 case 'n':
  83                         errno = 0;
  84                         tmp = strtol(optarg, &ep, 10);
  85                         if (*ep != '\0' || tmp < INT_MIN || tmp > INT_MAX)
  86                                 errx(EXIT_FAILURE, "invalid argument: `%s'",
  87                                     optarg);
  88                         niceness = (int)tmp;
  89                         break;
  90                 default:
  91                         usage();
  92                         break;
  93                 }
  94         }
  95         argc -= optind;
  96         argv += optind;
  97
  98         if (argc == 0)
  99                 usage();
 100
 101         errno = 0;
 102         niceness += getpriority(PRIO_PROCESS, 0);
 103         if (errno) {
 104                 err(EXIT_FAILURE, "getpriority");
 105                 /* NOTREACHED */
 106         }
 107         if (setpriority(PRIO_PROCESS, 0, niceness) == -1) {
 108                 warn("setpriority");
 109         }
 110
 111         (void)execvp(argv[0], &argv[0]);
 112         err((errno == ENOENT || errno == ENOTDIR) ? 127 : 126, "%s", argv[0]);
 113         /* NOTREACHED */
 114 }
 115
 116 static void
 117 usage(void)
 118 {
 119         (void)fprintf(stderr,
 120             "Usage: %s [ -n increment ] utility [ argument ...]\n",
 121             getprogname());
 122         exit(EXIT_FAILURE);
 123 }