xref: /netbsd/usr.bin/who/who.c (revision c4a72b64)
1 /*	$NetBSD: who.c,v 1.10 2002/08/01 23:23:09 christos 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. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #ifndef lint
41 __COPYRIGHT(
42 "@(#) Copyright (c) 1989, 1993\n\
43 	The Regents of the University of California.  All rights reserved.\n");
44 #endif /* not lint */
45 
46 #ifndef lint
47 #if 0
48 static char sccsid[] = "@(#)who.c	8.1 (Berkeley) 6/6/93";
49 #endif
50 __RCSID("$NetBSD: who.c,v 1.10 2002/08/01 23:23:09 christos Exp $");
51 #endif /* not lint */
52 
53 #include <sys/types.h>
54 #include <sys/stat.h>
55 #include <err.h>
56 #include <locale.h>
57 #include <pwd.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <time.h>
62 #include <unistd.h>
63 #include "utmpentry.h"
64 
65 static void output_labels(void);
66 static void who_am_i(const char *, int);
67 static void usage(void);
68 static void process(const char *, int);
69 static void print(const char *, const char *, time_t, const char *);
70 
71 int main(int, char **);
72 
73 static int show_term;			/* show term state */
74 static int show_idle;			/* show idle time */
75 
76 static int maxname = 8, maxline = 8, maxhost = 16;
77 
78 int
79 main(int argc, char **argv)
80 {
81 	int c, only_current_term, show_labels;
82 
83 	setlocale(LC_ALL, "");
84 
85 	only_current_term = show_term = show_idle = show_labels = 0;
86 	while ((c = getopt(argc, argv, "mTuH")) != -1) {
87 		switch (c) {
88 		case 'm':
89 			only_current_term = 1;
90 			break;
91 		case 'T':
92 			show_term = 1;
93 			break;
94 		case 'u':
95 			show_idle = 1;
96 			break;
97 		case 'H':
98 			show_labels = 1;
99 			break;
100 		default:
101 			usage();
102 			/* NOTREACHED */
103 		}
104 	}
105 	argc -= optind;
106 	argv += optind;
107 
108 	if (chdir("/dev")) {
109 		err(1, "cannot change directory to /dev");
110 		/* NOTREACHED */
111 	}
112 
113 	switch (argc) {
114 	case 0:					/* who */
115 		if (only_current_term) {
116 			who_am_i(NULL, show_labels);
117 		} else {
118 			process(NULL, show_labels);
119 		}
120 		break;
121 	case 1:					/* who utmp_file */
122 		if (only_current_term) {
123 			who_am_i(*argv, show_labels);
124 		} else {
125 			process(*argv, show_labels);
126 		}
127 		break;
128 	case 2:					/* who am i */
129 		who_am_i(NULL, show_labels);
130 		break;
131 	default:
132 		usage();
133 		/* NOTREACHED */
134 	}
135 	exit(0);
136 }
137 
138 static void
139 who_am_i(const char *fname, int show_labels)
140 {
141 	struct passwd *pw;
142 	char *p;
143 	char *t;
144 	time_t now;
145 	struct utmpentry *ehead, *ep;
146 
147 	/* search through the utmp and find an entry for this tty */
148 	if ((p = ttyname(STDIN_FILENO)) != NULL) {
149 
150 		/* strip any directory component */
151 		if ((t = strrchr(p, '/')) != NULL)
152 			p = t + 1;
153 
154 		(void)getutentries(fname, &ehead);
155 		for (ep = ehead; ep; ep = ep->next)
156 			if (strcmp(ep->line, p) == 0) {
157 				if (show_labels)
158 					output_labels();
159 				print(ep->name, ep->line, (time_t)ep->tv.tv_sec,
160 				    ep->host);
161 				return;
162 			}
163 	} else
164 		p = "tty??";
165 
166 	(void)time(&now);
167 	pw = getpwuid(getuid());
168 	if (show_labels)
169 		output_labels();
170 	print(pw ? pw->pw_name : "?", p, now, "");
171 }
172 
173 static void
174 process(const char *fname, int show_labels)
175 {
176 	struct utmpentry *ehead, *ep;
177 	(void)getutentries(fname, &ehead);
178 	if (show_labels)
179 		output_labels();
180 	for (ep = ehead; ep != NULL; ep = ep->next)
181 		print(ep->name, ep->line, (time_t)ep->tv.tv_sec, ep->host);
182 }
183 
184 static void
185 print(const char *name, const char *line, time_t t, const char *host)
186 {
187 	struct stat sb;
188 	char state;
189 	static time_t now = 0;
190 	time_t idle;
191 
192 	state = '?';
193 	idle = 0;
194 
195 	if (show_term || show_idle) {
196 		if (now == 0)
197 			time(&now);
198 
199 		if (stat(line, &sb) == 0) {
200 			state = (sb.st_mode & 020) ? '+' : '-';
201 			idle = now - sb.st_atime;
202 		}
203 
204 	}
205 
206 	(void)printf("%-*.*s ", maxname, maxname, name);
207 
208 	if (show_term) {
209 		(void)printf("%c ", state);
210 	}
211 
212 	(void)printf("%-*.*s ", maxline, maxline, line);
213 	(void)printf("%.12s ", ctime(&t) + 4);
214 
215 	if (show_idle) {
216 		if (idle < 60)
217 			(void)printf("  .   ");
218 		else if (idle < (24 * 60 * 60))
219 			(void)printf("%02ld:%02ld ",
220 				     (long)(idle / (60 * 60)),
221 				     (long)(idle % (60 * 60)) / 60);
222 		else
223 			(void)printf(" old  ");
224 	}
225 
226 	if (*host)
227 		printf("\t(%.*s)", maxhost, host);
228 	(void)putchar('\n');
229 }
230 
231 static void
232 output_labels()
233 {
234 	(void)printf("%-*.*s ", maxname, maxname, "USER");
235 
236 	if (show_term)
237 		(void)printf("S ");
238 
239 	(void)printf("%-*.*s ", maxline, maxline, "LINE");
240 	(void)printf("WHEN         ");
241 
242 	if (show_idle)
243 		(void)printf("IDLE  ");
244 
245 	(void)printf("\t%.*s", maxhost, "FROM");
246 
247 	(void)putchar('\n');
248 }
249 
250 static void
251 usage()
252 {
253 	(void)fprintf(stderr, "Usage: %s [-mTuH] [ file ]\n       %s am i\n",
254 	    getprogname(), getprogname());
255 	exit(1);
256 }
257