xref: /netbsd-src/usr.bin/who/who.c (revision e5548b402ae4c44fb816de42c7bba9581ce23ef5)
1 /*	$NetBSD: who.c,v 1.16 2005/07/22 14:23:05 peter Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Michael Fischbein.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 #ifndef lint
37 __COPYRIGHT(
38 "@(#) Copyright (c) 1989, 1993\n\
39 	The Regents of the University of California.  All rights reserved.\n");
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)who.c	8.1 (Berkeley) 6/6/93";
45 #endif
46 __RCSID("$NetBSD: who.c,v 1.16 2005/07/22 14:23:05 peter Exp $");
47 #endif /* not lint */
48 
49 #include <sys/types.h>
50 #include <sys/stat.h>
51 
52 #include <err.h>
53 #include <locale.h>
54 #include <pwd.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <time.h>
59 #include <unistd.h>
60 
61 #include "utmpentry.h"
62 
63 static void output_labels(void);
64 static void who_am_i(const char *, int);
65 static void usage(void);
66 static void process(const char *, int);
67 static void print(const char *, const char *, time_t, const char *);
68 static void quick(const char *);
69 
70 static int show_term;			/* show term state */
71 static int show_idle;			/* show idle time */
72 
73 extern int maxname, maxline, maxhost;
74 
75 int
76 main(int argc, char *argv[])
77 {
78 	int c, only_current_term, show_labels, quick_mode, default_mode;
79 
80 	setlocale(LC_ALL, "");
81 
82 	only_current_term = show_term = show_idle = show_labels = 0;
83 	quick_mode = default_mode = 0;
84 
85 	while ((c = getopt(argc, argv, "HmqsTu")) != -1) {
86 		switch (c) {
87 		case 'H':
88 			show_labels = 1;
89 			break;
90 		case 'm':
91 			only_current_term = 1;
92 			break;
93 		case 'q':
94 			quick_mode = 1;
95 			break;
96 		case 's':
97 			default_mode = 1;
98 			break;
99 		case 'T':
100 			show_term = 1;
101 			break;
102 		case 'u':
103 			show_idle = 1;
104 			break;
105 		default:
106 			usage();
107 			/* NOTREACHED */
108 		}
109 	}
110 	argc -= optind;
111 	argv += optind;
112 
113 	if (chdir("/dev")) {
114 		err(EXIT_FAILURE, "cannot change directory to /dev");
115 		/* NOTREACHED */
116 	}
117 
118 	if (default_mode)
119 		only_current_term = show_term = show_idle = 0;
120 
121 	switch (argc) {
122 	case 0:					/* who */
123 		if (quick_mode) {
124 			quick(NULL);
125 		} else if (only_current_term) {
126 			who_am_i(NULL, show_labels);
127 		} else {
128 			process(NULL, show_labels);
129 		}
130 		break;
131 	case 1:					/* who utmp_file */
132 		if (quick_mode) {
133 			quick(*argv);
134 		} else if (only_current_term) {
135 			who_am_i(*argv, show_labels);
136 		} else {
137 			process(*argv, show_labels);
138 		}
139 		break;
140 	case 2:					/* who am i */
141 		who_am_i(NULL, show_labels);
142 		break;
143 	default:
144 		usage();
145 		/* NOTREACHED */
146 	}
147 
148 	return 0;
149 }
150 
151 static void
152 who_am_i(const char *fname, int show_labels)
153 {
154 	struct passwd *pw;
155 	const char *p;
156 	char *t;
157 	time_t now;
158 	struct utmpentry *ehead, *ep;
159 
160 	/* search through the utmp and find an entry for this tty */
161 	if ((p = ttyname(STDIN_FILENO)) != NULL) {
162 
163 		/* strip any directory component */
164 		if ((t = strrchr(p, '/')) != NULL)
165 			p = t + 1;
166 
167 		(void)getutentries(fname, &ehead);
168 		for (ep = ehead; ep; ep = ep->next)
169 			if (strcmp(ep->line, p) == 0) {
170 				if (show_labels)
171 					output_labels();
172 				print(ep->name, ep->line, (time_t)ep->tv.tv_sec,
173 				    ep->host);
174 				return;
175 			}
176 	} else
177 		p = "tty??";
178 
179 	(void)time(&now);
180 	pw = getpwuid(getuid());
181 	if (show_labels)
182 		output_labels();
183 	print(pw ? pw->pw_name : "?", p, now, "");
184 }
185 
186 static void
187 process(const char *fname, int show_labels)
188 {
189 	struct utmpentry *ehead, *ep;
190 	(void)getutentries(fname, &ehead);
191 	if (show_labels)
192 		output_labels();
193 	for (ep = ehead; ep != NULL; ep = ep->next)
194 		print(ep->name, ep->line, (time_t)ep->tv.tv_sec, ep->host);
195 }
196 
197 static void
198 print(const char *name, const char *line, time_t t, const char *host)
199 {
200 	struct stat sb;
201 	char state;
202 	static time_t now = 0;
203 	time_t idle;
204 
205 	state = '?';
206 	idle = 0;
207 
208 	if (show_term || show_idle) {
209 		if (now == 0)
210 			time(&now);
211 
212 		if (stat(line, &sb) == 0) {
213 			state = (sb.st_mode & 020) ? '+' : '-';
214 			idle = now - sb.st_atime;
215 		}
216 
217 	}
218 
219 	(void)printf("%-*.*s ", maxname, maxname, name);
220 
221 	if (show_term)
222 		(void)printf("%c ", state);
223 
224 	(void)printf("%-*.*s ", maxline, maxline, line);
225 	(void)printf("%.12s ", ctime(&t) + 4);
226 
227 	if (show_idle) {
228 		if (idle < 60)
229 			(void)printf("  .   ");
230 		else if (idle < (24 * 60 * 60))
231 			(void)printf("%02ld:%02ld ",
232 				     (long)(idle / (60 * 60)),
233 				     (long)(idle % (60 * 60)) / 60);
234 		else
235 			(void)printf(" old  ");
236 	}
237 
238 	if (*host)
239 		(void)printf("\t(%.*s)", maxhost, host);
240 	(void)putchar('\n');
241 }
242 
243 static void
244 output_labels(void)
245 {
246 	(void)printf("%-*.*s ", maxname, maxname, "USER");
247 
248 	if (show_term)
249 		(void)printf("S ");
250 
251 	(void)printf("%-*.*s ", maxline, maxline, "LINE");
252 	(void)printf("WHEN         ");
253 
254 	if (show_idle)
255 		(void)printf("IDLE  ");
256 
257 	(void)printf("\t%.*s", maxhost, "FROM");
258 
259 	(void)putchar('\n');
260 }
261 
262 static void
263 quick(const char *fname)
264 {
265 	struct utmpentry *ehead, *ep;
266 	int num = 0;
267 
268 	(void)getutentries(fname, &ehead);
269 	for (ep = ehead; ep != NULL; ep = ep->next) {
270 		(void)printf("%-*s ", maxname, ep->name);
271 		if ((++num % 8) == 0)
272 			(void)putchar('\n');
273 	}
274 	if (num % 8)
275 		(void)putchar('\n');
276 
277 	(void)printf("# users = %d\n", num);
278 }
279 
280 static void
281 usage(void)
282 {
283 	(void)fprintf(stderr, "usage: %s [-HmqsTu] [file]\n       %s am i\n",
284 	    getprogname(), getprogname());
285 	exit(EXIT_FAILURE);
286 }
287