xref: /illumos-gate/usr/src/cmd/nice/nice.c (revision 7c478bd9)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
23 /*	  All Rights Reserved  	*/
24 
25 
26 /*
27  * Copyright 2000-2003 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #pragma ident	"%Z%%M%	%I%	%E% SMI"
32 
33 /*
34 **	nice
35 */
36 
37 
38 #include	<stdio.h>
39 #include	<locale.h>
40 #include	<stdlib.h>
41 #include	<string.h>
42 #include	<unistd.h>
43 #include	<errno.h>
44 
45 
46 static void usage(void);
47 
48 int
main(int argc,char * argv[])49 main(int argc, char *argv[])
50 {
51 	long	nicarg = 10;
52 
53 	(void) setlocale(LC_ALL, "");
54 #if !defined(TEXT_DOMAIN)
55 #define	TEXT_DOMAIN	"SYS_TEST"
56 #endif
57 	(void) textdomain(TEXT_DOMAIN);
58 
59 
60 	if (argc < 2)
61 		usage();
62 
63 
64 	if (argv[1][0] == '-') {
65 		if (strcmp(argv[1], "--") == 0) {
66 			argv++;
67 			argc--;
68 		} else {
69 			register char	*p = argv[1];
70 			char	*nicarg_str;
71 			char 	*end_ptr;
72 
73 			if (*++p == 'n') {	/* -n55 new form, XCU4 */
74 				/*
75 				 * for situations like -n-10
76 				 * else case assigns p instead of argv
77 				 */
78 				if (!(*++p)) {
79 					/* Next arg is priority */
80 					argv++;
81 					argc--;
82 					if (argc < 2)
83 						usage();
84 					nicarg_str = argv[1];
85 				} else {
86 					/* Priority embedded eg. -n-10 */
87 					nicarg_str = p;
88 				}
89 			} else {	/* -55 obs form, XCU4 */
90 				nicarg_str = &argv[1][1];
91 			}
92 			nicarg = strtol(nicarg_str, &end_ptr, 10);
93 			if (*end_ptr) {
94 				(void) fprintf(stderr,
95 				gettext("nice: argument must be numeric.\n"));
96 				usage();
97 			}
98 
99 			if( --argc < 2 )
100 				usage();
101 
102 			argv++;
103 			if (strcmp(argv[1], "--") == 0) {
104 				argv++;
105 				argc--;
106 			}
107 		}
108 	}
109 
110 	if (argc < 2)
111 		usage();
112 
113 	errno = 0;
114 	if (nice(nicarg) == -1) {
115 		/*
116 		 * Could be an error or a legitimate return value.
117 		 * The only error we care about is EINVAL, which will
118 		 * be returned by the scheduling class we are in if
119 		 * nice is invalid for this class.
120 		 * For any error other than EINVAL
121 		 * we will go ahead and exec the command even though
122 		 * the priority change failed.
123 		 */
124 		if (errno == EINVAL) {
125 			(void) fprintf(stderr, gettext(
126 			    "nice: invalid operation; "
127 			    "scheduling class does not support nice\n"));
128 			return (2);
129 		}
130 	}
131 	(void) execvp(argv[1], &argv[1]);
132 	(void) fprintf(stderr, gettext("%s: %s\n"), strerror(errno), argv[1]);
133 	/*
134 	 * POSIX.2 exit status:
135 	 * 127 if utility is not found.
136 	 * 126 if utility cannot be invoked.
137 	 */
138 	return (errno == ENOENT || errno == ENOTDIR ? 127 : 126);
139 }
140 
141 static void
usage()142 usage()
143 {
144 	(void) fprintf(stderr,
145 	gettext("nice: usage: nice [-n increment] utility [argument ...]\n"));
146 	exit(2);
147 }
148