1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993, 1994
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/types.h>
33#include <sys/time.h>
34#include <sys/resource.h>
35
36#include <ctype.h>
37#include <err.h>
38#include <errno.h>
39#include <limits.h>
40#include <stdio.h>
41#include <stdlib.h>
42#include <unistd.h>
43#include <string.h>
44
45#define	DEFNICE	10
46
47void usage(void);
48
49int
50main(int argc, char *argv[])
51{
52	long niceness = DEFNICE;
53	int ch;
54	char *ep;
55
56	/* Obsolescent syntax: -number, --number */
57	if (argc >= 2 && argv[1][0] == '-' && (argv[1][1] == '-' ||
58	    isdigit((unsigned char)argv[1][1])) && strcmp(argv[1], "--") != 0)
59		if (asprintf(&argv[1], "-n%s", argv[1] + 1) < 0)
60			err(1, "asprintf");
61
62	while ((ch = getopt(argc, argv, "n:")) != -1) {
63		switch (ch) {
64		case 'n':
65			errno = 0;
66			niceness = strtol(optarg, &ep, 10);
67			if (ep == optarg || *ep != '\0' || errno ||
68			    niceness < INT_MIN || niceness > INT_MAX)
69				errx(1, "%s: invalid nice value", optarg);
70			break;
71		default:
72			usage();
73		}
74	}
75	argc -= optind;
76	argv += optind;
77
78	if (argc == 0)
79		usage();
80
81	errno = 0;
82	niceness += getpriority(PRIO_PROCESS, 0);
83	if (errno)
84		warn("getpriority");
85	else if (setpriority(PRIO_PROCESS, 0, (int)niceness))
86		warn("setpriority");
87	execvp(*argv, argv);
88	err(errno == ENOENT ? 127 : 126, "%s", *argv);
89}
90
91void
92usage(void)
93{
94
95	(void)fprintf(stderr,
96	    "usage: nice [-n increment] utility [argument ...]\n");
97	exit(1);
98}
99