xref: /minix/usr.bin/users/users.c (revision ebfedea0)
1 /*	$NetBSD: users.c,v 1.16 2012/03/20 20:34:59 matt Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1987, 1993
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/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1987, 1993\
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[] = "@(#)users.c	8.1 (Berkeley) 6/6/93";
41 #endif
42 __RCSID("$NetBSD: users.c,v 1.16 2012/03/20 20:34:59 matt Exp $");
43 #endif /* not lint */
44 
45 #include <sys/types.h>
46 
47 #include <err.h>
48 #include <time.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 
54 #include "utmpentry.h"
55 
56 int	main(int, char **);
57 
58 int
59 main(int argc, char **argv)
60 {
61 	int ncnt = 0;
62 	int ch;
63 	struct utmpentry *from, *ehead, *save, **nextp;
64 
65 	while ((ch = getopt(argc, argv, "")) != -1)
66 		switch(ch) {
67 		case '?':
68 		default:
69 			(void)fprintf(stderr, "usage: %s\n", getprogname());
70 			exit(1);
71 		}
72 	argc -= optind;
73 	argv += optind;
74 
75 	ncnt = getutentries(NULL, &ehead);
76 
77 	if (ncnt == 0)
78 		return 0;
79 
80 	/*
81 	 * XXX the utmp list belongs to getutentries and we shouldn't
82 	 * sort it in place. Since we don't call endutentries and we
83 	 * don't call getutentries again it doesn't matter, but it's
84 	 * untidy. Maybe give getutentries a sort function? It has to
85 	 * sort anyway if it's merging utmp and utmpx data.
86 	 */
87 
88 	from = ehead;
89 	ehead = NULL;
90 	while (from != NULL) {
91 		for (nextp = &ehead;
92 		    (*nextp) && strcmp(from->name, (*nextp)->name) > 0;
93 		    nextp = &(*nextp)->next)
94 			continue;
95 		save = from;
96 		from = from->next;
97 		save->next = *nextp;
98 		*nextp = save;
99 	}
100 
101 	save = ehead;
102 	(void)printf("%s", ehead->name);
103 
104 	for (from = ehead->next; from; from = from->next)
105 		if (strcmp(save->name, from->name) != 0) {
106 			(void)printf(" %s", from->name);
107 			save = from;
108 		}
109 
110 	(void)printf("\n");
111 	exit(0);
112 }
113