xref: /dragonfly/usr.sbin/lastlogin/lastlogin.c (revision 92fc8b5c)
1 /*
2  * Copyright (c) 1996 John M. Vinopal
3  * 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 for the NetBSD Project
16  *	by John M. Vinopal.
17  * 4. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
25  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
27  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * $NetBSD: lastlogin.c,v 1.4 1998/02/03 04:45:35 perry Exp $
33  * $FreeBSD: src/usr.sbin/lastlogin/lastlogin.c,v 1.2.2.2 2001/07/19 05:02:46 kris Exp $
34  * $DragonFly: src/usr.sbin/lastlogin/lastlogin.c,v 1.5 2004/11/13 16:14:33 liamfoy Exp $
35  */
36 
37 #include <sys/cdefs.h>
38 #include <sys/user.h>
39 
40 #include <err.h>
41 #include <pwd.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <time.h>
45 #include <utmp.h>
46 #include <utmpx.h>
47 #include <unistd.h>
48 
49 static	void	output(struct passwd *, struct lastlog *);
50 static	void	outputx(struct passwd *, struct lastlogx *);
51 static	void	usage(void);
52 
53 int
54 main(int argc, char **argv)
55 {
56 	int	ch, i;
57 	long offset;
58 	FILE	*fp;
59 	struct passwd	*passwd;
60 	struct lastlog	last;
61 	struct lastlogx	lastx;
62 
63 	while ((ch = getopt(argc, argv, "")) != -1) {
64 		usage();
65 	}
66 
67 	if ((fp = fopen(_PATH_LASTLOG, "r")) == NULL)
68 		err(1, "%s", _PATH_LASTLOG);
69 
70 	setpassent(1);	/* Keep passwd file pointers open */
71 
72 	/* Process usernames given on the command line. */
73 	if (argc > 1) {
74 		for (i = 1; i < argc; ++i) {
75 			if ((passwd = getpwnam(argv[i])) == NULL) {
76 				warnx("user '%s' not found", argv[i]);
77 				continue;
78 			}
79 			if ((getlastlogx(_PATH_LASTLOGX, passwd->pw_uid,
80 			    &lastx)) != NULL) {
81 				outputx(passwd, &lastx);
82 				goto done;
83 			}
84 			/* Calculate the offset into the lastlog file. */
85 			offset = (long)(passwd->pw_uid * sizeof(last));
86 			if (fseek(fp, offset, SEEK_SET)) {
87 				warn("fseek error");
88 				continue;
89 			}
90 			if (fread(&last, sizeof(last), 1, fp) != 1) {
91 				warnx("fread error on '%s'", passwd->pw_name);
92 				clearerr(fp);
93 				continue;
94 			}
95 			output(passwd, &last);
96 		}
97 	}
98 	/* Read all lastlog entries, looking for active ones */
99 	else {
100 		while ((passwd = getpwent()) != NULL) {
101 			if ((getlastlogx(_PATH_LASTLOGX, passwd->pw_uid,
102 			    &lastx)) != NULL) {
103 				if (lastx.ll_tv.tv_sec == 0)
104 					continue;
105 				outputx(passwd, &lastx);
106 			} else {
107 				offset = (long)(passwd->pw_uid * sizeof(last));
108 
109 				if (fseek(fp, offset, SEEK_SET)) {
110 					continue;
111 				}
112 				if (fread(&last, sizeof(last), 1, fp) != 1) {
113 					continue;
114 				}
115 				if (last.ll_time == 0)
116 					continue;
117 				output(passwd, &last);
118 			}
119 		}
120 #if 0
121 		for (i = 0; fread(&last, sizeof(last), 1, fp) == 1; i++) {
122 			if (last.ll_time == 0)
123 				continue;
124 			if ((passwd = getpwuid((uid_t)i)) != NULL)
125 				output(passwd, &last);
126 		}
127 		if (ferror(fp))
128 			warnx("fread error");
129 #endif
130 	}
131 
132 done:
133 	setpassent(0);	/* Close passwd file pointers */
134 
135 	fclose(fp);
136 	exit(0);
137 }
138 
139 /* Duplicate the output of last(1) */
140 static void
141 output(struct passwd *p, struct lastlog *l)
142 {
143 	printf("%-*.*s  %-*.*s %-*.*s   %s",
144 		UT_NAMESIZE, UT_NAMESIZE, p->pw_name,
145 		UT_LINESIZE+4, UT_LINESIZE+4, l->ll_line,
146 		UT_HOSTSIZE, UT_HOSTSIZE, l->ll_host,
147 		(l->ll_time) ? ctime(&(l->ll_time)) : "Never logged in\n");
148 }
149 
150 static void
151 outputx(struct passwd *p, struct lastlogx *l)
152 {
153 	printf("%-*.*s  %-*.*s %-*.*s   %s",
154 		UT_NAMESIZE, UT_NAMESIZE, p->pw_name,
155 		UT_LINESIZE+4, UT_LINESIZE+4, l->ll_line,
156 		UT_HOSTSIZE, UT_HOSTSIZE, l->ll_host,
157 		(l->ll_tv.tv_sec) ? ctime((&l->ll_tv.tv_sec)) : "Never logged in\n");
158 }
159 
160 static void
161 usage(void)
162 {
163 	fprintf(stderr, "usage: lastlogin [user ...]\n");
164 	exit(1);
165 }
166