1/*-
2 * Copyright (c) 2002 Tim J. Robbins.
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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include <sys/param.h>
31#include <sys/types.h>
32#include <sys/ioctl.h>
33#include <sys/stat.h>
34
35#include <err.h>
36#include <errno.h>
37#include <langinfo.h>
38#include <limits.h>
39#include <locale.h>
40#include <paths.h>
41#include <pwd.h>
42#include <stdio.h>
43#include <stdlib.h>
44#include <string.h>
45#include <time.h>
46#include <timeconv.h>
47#include <unistd.h>
48#include <utmpx.h>
49
50static void	heading(void);
51static void	process_utmp(void);
52static void	quick(void);
53static void	row(const struct utmpx *);
54static int	ttywidth(void);
55static void	usage(void);
56static void	whoami(void);
57
58static int	Hflag;			/* Write column headings */
59static int	aflag;			/* Print all entries */
60static int	bflag;			/* Show date of the last reboot */
61static int	mflag;			/* Show info about current terminal */
62static int	qflag;			/* "Quick" mode */
63static int	sflag;			/* Show name, line, time */
64static int	Tflag;			/* Show terminal state */
65static int	uflag;			/* Show idle time */
66
67int
68main(int argc, char *argv[])
69{
70	int ch;
71
72	setlocale(LC_TIME, "");
73
74	while ((ch = getopt(argc, argv, "HTabmqsu")) != -1) {
75		switch (ch) {
76		case 'H':		/* Write column headings */
77			Hflag = 1;
78			break;
79		case 'T':		/* Show terminal state */
80			Tflag = 1;
81			break;
82		case 'a':		/* Same as -bdlprtTu */
83			aflag = bflag = Tflag = uflag = 1;
84			break;
85		case 'b':		/* Show date of the last reboot */
86			bflag = 1;
87			break;
88		case 'm':		/* Show info about current terminal */
89			mflag = 1;
90			break;
91		case 'q':		/* "Quick" mode */
92			qflag = 1;
93			break;
94		case 's':		/* Show name, line, time */
95			sflag = 1;
96			break;
97		case 'u':		/* Show idle time */
98			uflag = 1;
99			break;
100		default:
101			usage();
102			/*NOTREACHED*/
103		}
104	}
105	argc -= optind;
106	argv += optind;
107
108	if (argc >= 2 && strcmp(argv[0], "am") == 0 &&
109	    (strcmp(argv[1], "i") == 0 || strcmp(argv[1], "I") == 0)) {
110		/* "who am i" or "who am I", equivalent to -m */
111		mflag = 1;
112		argc -= 2;
113		argv += 2;
114	}
115	if (argc > 1)
116		usage();
117
118	if (*argv != NULL) {
119		if (setutxdb(UTXDB_ACTIVE, *argv) != 0)
120			err(1, "%s", *argv);
121	}
122
123	if (qflag)
124		quick();
125	else {
126		if (sflag)
127			Tflag = uflag = 0;
128		if (Hflag)
129			heading();
130		if (mflag)
131			whoami();
132		else
133			process_utmp();
134	}
135
136	endutxent();
137
138	exit(0);
139}
140
141static void
142usage(void)
143{
144
145	fprintf(stderr, "usage: who [-abHmqsTu] [am I] [file]\n");
146	exit(1);
147}
148
149static void
150heading(void)
151{
152
153	printf("%-16s ", "NAME");
154	if (Tflag)
155		printf("S ");
156	printf("%-12s %-12s ", "LINE", "TIME");
157	if (uflag)
158		printf("IDLE  ");
159	printf("%-16s\n", "FROM");
160}
161
162static void
163row(const struct utmpx *ut)
164{
165	char buf[80], tty[PATH_MAX];
166	struct stat sb;
167	time_t idle, t;
168	static int d_first = -1;
169	struct tm *tm;
170	char state;
171
172	if (d_first < 0)
173		d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
174
175	state = '?';
176	idle = 0;
177	if (Tflag || uflag) {
178		snprintf(tty, sizeof(tty), "%s%s", _PATH_DEV, ut->ut_line);
179		if (stat(tty, &sb) == 0) {
180			state = sb.st_mode & (S_IWOTH|S_IWGRP) ?
181			    '+' : '-';
182			idle = time(NULL) - sb.st_mtime;
183		}
184	}
185
186	printf("%-16s ", ut->ut_user);
187	if (Tflag)
188		printf("%c ", state);
189	if (ut->ut_type == BOOT_TIME)
190		printf("%-12s ", "system boot");
191	else
192		printf("%-12s ", ut->ut_line);
193	t = ut->ut_tv.tv_sec;
194	tm = localtime(&t);
195	strftime(buf, sizeof(buf), d_first ? "%e %b %R" : "%b %e %R", tm);
196	printf("%-*s ", 12, buf);
197	if (uflag) {
198		if (idle < 60)
199			printf("  .   ");
200		else if (idle < 24 * 60 * 60)
201			printf("%02d:%02d ", (int)(idle / 60 / 60),
202			    (int)(idle / 60 % 60));
203		else
204			printf(" old  ");
205	}
206	if (*ut->ut_host != '\0')
207		printf("(%s)", ut->ut_host);
208	putchar('\n');
209}
210
211static int
212ttystat(char *line)
213{
214	struct stat sb;
215	char ttybuf[MAXPATHLEN];
216
217	(void)snprintf(ttybuf, sizeof(ttybuf), "%s%s", _PATH_DEV, line);
218	if (stat(ttybuf, &sb) == 0) {
219		return (0);
220	} else
221		return (-1);
222}
223
224static void
225process_utmp(void)
226{
227	struct utmpx *utx;
228
229	while ((utx = getutxent()) != NULL) {
230		if (((aflag || !bflag) && utx->ut_type == USER_PROCESS) ||
231		    (bflag && utx->ut_type == BOOT_TIME))
232			if (ttystat(utx->ut_line) == 0)
233				row(utx);
234	}
235}
236
237static void
238quick(void)
239{
240	struct utmpx *utx;
241	int col, ncols, num;
242
243	ncols = ttywidth();
244	col = num = 0;
245	while ((utx = getutxent()) != NULL) {
246		if (utx->ut_type != USER_PROCESS)
247			continue;
248		printf("%-16s", utx->ut_user);
249		if (++col < ncols / (16 + 1))
250			putchar(' ');
251		else {
252			col = 0;
253			putchar('\n');
254		}
255		num++;
256	}
257	if (col != 0)
258		putchar('\n');
259
260	printf("# users = %d\n", num);
261}
262
263static void
264whoami(void)
265{
266	struct utmpx ut, *utx;
267	struct passwd *pwd;
268	const char *name, *tty;
269
270	if ((tty = ttyname(STDIN_FILENO)) == NULL)
271		tty = "tty??";
272	else if (strncmp(tty, _PATH_DEV, sizeof _PATH_DEV - 1) == 0)
273		tty += sizeof _PATH_DEV - 1;
274	strlcpy(ut.ut_line, tty, sizeof ut.ut_line);
275
276	/* Search utmp for our tty, dump first matching record. */
277	if ((utx = getutxline(&ut)) != NULL && utx->ut_type == USER_PROCESS) {
278		row(utx);
279		return;
280	}
281
282	/* Not found; fill the utmp structure with the information we have. */
283	memset(&ut, 0, sizeof(ut));
284	if ((pwd = getpwuid(getuid())) != NULL)
285		name = pwd->pw_name;
286	else
287		name = "?";
288	strlcpy(ut.ut_user, name, sizeof ut.ut_user);
289	gettimeofday(&ut.ut_tv, NULL);
290	row(&ut);
291}
292
293static int
294ttywidth(void)
295{
296	struct winsize ws;
297	long width;
298	char *cols, *ep;
299
300	if ((cols = getenv("COLUMNS")) != NULL && *cols != '\0') {
301		errno = 0;
302		width = strtol(cols, &ep, 10);
303		if (errno || width <= 0 || width > INT_MAX || ep == cols ||
304		    *ep != '\0')
305			warnx("invalid COLUMNS environment variable ignored");
306		else
307			return (width);
308	}
309	if (ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) != -1)
310		return (ws.ws_col);
311
312	return (80);
313}
314