xref: /openbsd-src/usr.bin/w/w.c (revision c1a45aed656e7d5627c30c92421893a76f370ccb)
1 /*	$OpenBSD: w.c,v 1.67 2022/02/22 17:35:01 deraadt Exp $	*/
2 
3 /*-
4  * Copyright (c) 1980, 1991, 1993, 1994
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 /*
33  * w - print system status (who and what)
34  *
35  * This program is similar to the systat command on Tenex/Tops 10/20
36  *
37  */
38 #include <sys/time.h>
39 #include <sys/stat.h>
40 #include <sys/sysctl.h>
41 #include <sys/signal.h>
42 #include <sys/proc.h>
43 #include <sys/ioctl.h>
44 #include <sys/socket.h>
45 #include <sys/tty.h>
46 
47 #include <netinet/in.h>
48 #include <arpa/inet.h>
49 
50 #include <ctype.h>
51 #include <err.h>
52 #include <errno.h>
53 #include <fcntl.h>
54 #include <kvm.h>
55 #include <netdb.h>
56 #include <nlist.h>
57 #include <paths.h>
58 #include <stdio.h>
59 #include <stdlib.h>
60 #include <string.h>
61 #include <unistd.h>
62 #include <limits.h>
63 #include <utmp.h>
64 #include <vis.h>
65 
66 #include "extern.h"
67 
68 struct utmp	utmp;
69 struct winsize	ws;
70 kvm_t	       *kd;
71 time_t		now;		/* the current time of day */
72 int		ttywidth;	/* width of tty */
73 int		argwidth;	/* width of tty */
74 int		header = 1;	/* true if -h flag: don't print heading */
75 int		nflag = 1;	/* true if -n flag: don't convert addrs */
76 int		sortidle;	/* sort by idle time */
77 char	       *sel_user;	/* login of particular user selected */
78 char		domain[HOST_NAME_MAX+1];
79 
80 #define	NAME_WIDTH	8
81 #define HOST_WIDTH	16
82 
83 /*
84  * One of these per active utmp entry.
85  */
86 struct	entry {
87 	struct	entry *next;
88 	struct	utmp utmp;
89 	dev_t	tdev;			/* dev_t of terminal */
90 	time_t	idle;			/* idle time of terminal in seconds */
91 	struct	kinfo_proc *kp;		/* `most interesting' proc */
92 } *ep, *ehead = NULL, **nextp = &ehead;
93 
94 static void	 fmt_putc(int, int *);
95 static void	 fmt_puts(const char *, int *);
96 static void	 pr_args(struct kinfo_proc *);
97 static void	 pr_header(time_t *, int);
98 static struct stat
99 		*ttystat(char *);
100 static void	 usage(int);
101 
102 int
103 main(int argc, char *argv[])
104 {
105 	extern char *__progname;
106 	struct kinfo_proc *kp;
107 	struct hostent *hp;
108 	struct stat *stp;
109 	FILE *ut;
110 	struct in_addr addr;
111 	int ch, i, nentries, nusers, wcmd;
112 	char *memf, *nlistf, *p, *x;
113 	char buf[HOST_NAME_MAX+1], errbuf[_POSIX2_LINE_MAX];
114 
115 	/* Are we w(1) or uptime(1)? */
116 	p = __progname;
117 	if (*p == '-')
118 		p++;
119 	if (p[0] == 'w' && p[1] == '\0') {
120 		wcmd = 1;
121 		p = "hiflM:N:asuw";
122 	} else if (!strcmp(p, "uptime")) {
123 		wcmd = 0;
124 		p = "";
125 	} else
126 		errx(1,
127 		 "this program should be invoked only as \"w\" or \"uptime\"");
128 
129 	memf = nlistf = NULL;
130 	while ((ch = getopt(argc, argv, p)) != -1)
131 		switch (ch) {
132 		case 'h':
133 			header = 0;
134 			break;
135 		case 'i':
136 			sortidle = 1;
137 			break;
138 		case 'M':
139 			header = 0;
140 			memf = optarg;
141 			break;
142 		case 'N':
143 			nlistf = optarg;
144 			break;
145 		case 'a':
146 			nflag = 0;
147 			break;
148 		case 'f': case 'l': case 's': case 'u': case 'w':
149 			warnx("[-flsuw] no longer supported");
150 			/* FALLTHROUGH */
151 		case '?':
152 		default:
153 			usage(wcmd);
154 		}
155 	argc -= optind;
156 	argv += optind;
157 
158 	if (nflag == 0) {
159 		if (pledge("stdio tty rpath dns ps vminfo", NULL) == -1)
160 			err(1, "pledge");
161 	} else {
162 		if (pledge("stdio tty rpath ps vminfo", NULL) == -1)
163 			err(1, "pledge");
164 	}
165 
166 	if (nlistf == NULL && memf == NULL) {
167 		if ((kd = kvm_openfiles(nlistf, memf, NULL, KVM_NO_FILES,
168 		    errbuf)) == NULL)
169 			errx(1, "%s", errbuf);
170 	} else {
171 		if ((kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf)) == NULL)
172 			errx(1, "%s", errbuf);
173 	}
174 
175 	(void)time(&now);
176 	if ((ut = fopen(_PATH_UTMP, "r")) == NULL)
177 		err(1, "%s", _PATH_UTMP);
178 
179 	if (*argv)
180 		sel_user = *argv;
181 
182 	for (nusers = 0; fread(&utmp, sizeof(utmp), 1, ut);) {
183 		if (utmp.ut_name[0] == '\0')
184 			continue;
185 		++nusers;
186 		if (wcmd == 0 || (sel_user &&
187 		    strncmp(utmp.ut_name, sel_user, UT_NAMESIZE) != 0))
188 			continue;
189 		if ((ep = calloc(1, sizeof(*ep))) == NULL)
190 			err(1, NULL);
191 		*nextp = ep;
192 		nextp = &(ep->next);
193 		memcpy(&(ep->utmp), &utmp, sizeof(utmp));
194 		if (!(stp = ttystat(ep->utmp.ut_line)))
195 			continue;
196 		ep->tdev = stp->st_rdev;
197 
198 		/*
199 		 * If this is the console device, attempt to ascertain
200 		 * the true console device dev_t.
201 		 */
202 		if (ep->tdev == 0) {
203 			int mib[2];
204 			size_t size;
205 
206 			mib[0] = CTL_KERN;
207 			mib[1] = KERN_CONSDEV;
208 			size = sizeof(dev_t);
209 			(void) sysctl(mib, 2, &ep->tdev, &size, NULL, 0);
210 		}
211 
212 		if ((ep->idle = now - stp->st_atime) < 0)
213 			ep->idle = 0;
214 	}
215 	(void)fclose(ut);
216 
217 	if (header || wcmd == 0) {
218 		pr_header(&now, nusers);
219 		if (wcmd == 0)
220 			exit (0);
221 	}
222 
223 #define HEADER	"USER    TTY FROM              LOGIN@  IDLE WHAT"
224 #define WUSED	(sizeof(HEADER) - sizeof("WHAT"))
225 	if (header)
226 		(void)puts(HEADER);
227 
228 	kp = kvm_getprocs(kd, KERN_PROC_ALL, 0, sizeof(*kp), &nentries);
229 	if (kp == NULL)
230 		errx(1, "%s", kvm_geterr(kd));
231 
232 	if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 &&
233 	    ioctl(STDERR_FILENO, TIOCGWINSZ, &ws) == -1 &&
234 	    ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) == -1) || ws.ws_col == 0)
235 		ttywidth = 79;
236 	else
237 		ttywidth = ws.ws_col - 1;
238 	argwidth = ttywidth - WUSED;
239 	if (argwidth < 4)
240 		argwidth = 8;
241 
242 	for (i = 0; i < nentries; i++, kp++) {
243 		if (kp->p_psflags & (PS_EMBRYO | PS_ZOMBIE))
244 			continue;
245 		for (ep = ehead; ep != NULL; ep = ep->next) {
246 			/* ftp is a special case. */
247 			if (strncmp(ep->utmp.ut_line, "ftp", 3) == 0) {
248 				char pidstr[UT_LINESIZE-2];
249 				pid_t fp;
250 
251 				(void)strncpy(pidstr, &ep->utmp.ut_line[3],
252 				    sizeof(pidstr) - 1);
253 				pidstr[sizeof(pidstr) - 1] = '\0';
254 				fp = (pid_t)strtol(pidstr, NULL, 10);
255 				if (kp->p_pid == fp) {
256 					ep->kp = kp;
257 					break;
258 				}
259 			} else if (ep->tdev == kp->p_tdev &&
260 			    kp->p__pgid == kp->p_tpgid) {
261 				/*
262 				 * Proc is in foreground of this terminal
263 				 */
264 				if (proc_compare(ep->kp, kp))
265 					ep->kp = kp;
266 				break;
267 			}
268 		}
269 	}
270 	/* sort by idle time */
271 	if (sortidle && ehead != NULL) {
272 		struct entry *from = ehead, *save;
273 
274 		ehead = NULL;
275 		while (from != NULL) {
276 			for (nextp = &ehead;
277 			    (*nextp) && from->idle >= (*nextp)->idle;
278 			    nextp = &(*nextp)->next)
279 				continue;
280 			save = from;
281 			from = from->next;
282 			save->next = *nextp;
283 			*nextp = save;
284 		}
285 	}
286 
287 	if (!nflag) {
288 		if (gethostname(domain, sizeof(domain)) == -1 ||
289 		    (p = strchr(domain, '.')) == 0)
290 			domain[0] = '\0';
291 		else {
292 			domain[sizeof(domain) - 1] = '\0';
293 			memmove(domain, p, strlen(p) + 1);
294 		}
295 	}
296 
297 	for (ep = ehead; ep != NULL; ep = ep->next) {
298 		p = *ep->utmp.ut_host ? ep->utmp.ut_host : "-";
299 		for (x = NULL, i = 0; p[i] != '\0' && i < UT_HOSTSIZE; i++)
300 			if (p[i] == ':') {
301 				x = &p[i];
302 				*x++ = '\0';
303 				break;
304 			}
305 		if (!nflag && inet_aton(p, &addr) &&
306 		    (hp = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET))) {
307 			if (domain[0] != '\0') {
308 				p = hp->h_name;
309 				p += strlen(hp->h_name);
310 				p -= strlen(domain);
311 				if (p > hp->h_name &&
312 				    strcasecmp(p, domain) == 0)
313 					*p = '\0';
314 			}
315 			p = hp->h_name;
316 		}
317 		if (x) {
318 			(void)snprintf(buf, sizeof(buf), "%s:%.*s", p,
319 			    (int)(ep->utmp.ut_host + UT_HOSTSIZE - x), x);
320 			p = buf;
321 		}
322 		(void)printf("%-*.*s %-2.2s %-*.*s ",
323 		    NAME_WIDTH, UT_NAMESIZE, ep->utmp.ut_name,
324 		    strncmp(ep->utmp.ut_line, "tty", 3) ?
325 		    ep->utmp.ut_line : ep->utmp.ut_line + 3,
326 		    HOST_WIDTH, HOST_WIDTH, *p ? p : "-");
327 		pr_attime(&ep->utmp.ut_time, &now);
328 		pr_idle(ep->idle);
329 		pr_args(ep->kp);
330 		printf("\n");
331 	}
332 	exit(0);
333 }
334 
335 static void
336 fmt_putc(int c, int *leftp)
337 {
338 
339 	if (*leftp == 0)
340 		return;
341 	if (*leftp != -1)
342 		*leftp -= 1;
343 	putchar(c);
344 }
345 
346 static void
347 fmt_puts(const char *s, int *leftp)
348 {
349 	static char *v = NULL;
350 	static size_t maxlen = 0;
351 	size_t len;
352 
353 	if (*leftp == 0)
354 		return;
355 	len = strlen(s) * 4 + 1;
356 	if (len > maxlen) {
357 		free(v);
358 		maxlen = 0;
359 		if (len < getpagesize())
360 			len = getpagesize();
361 		v = malloc(len);
362 		if (v == NULL)
363 			return;
364 		maxlen = len;
365 	}
366 	strvis(v, s, VIS_TAB | VIS_NL | VIS_CSTYLE);
367 	if (*leftp != -1) {
368 		len = strlen(v);
369 		if (len > *leftp) {
370 			v[*leftp] = '\0';
371 			*leftp = 0;
372 		} else
373 			*leftp -= len;
374 	}
375 	printf("%s", v);
376 }
377 
378 
379 static void
380 pr_args(struct kinfo_proc *kp)
381 {
382 	char **argv, *str;
383 	int left;
384 
385 	if (kp == NULL)
386 		goto nothing;		/* no matching process found */
387 	left = argwidth;
388 	argv = kvm_getargv(kd, kp, argwidth+60);  /* +60 for ftpd snip */
389 	if (argv == NULL)
390 		goto nothing;
391 
392 	if (*argv == NULL || **argv == '\0') {
393 		/* Process has zeroed argv[0], display executable name. */
394 		fmt_putc('(', &left);
395 		fmt_puts(kp->p_comm, &left);
396 		fmt_putc(')', &left);
397 	}
398 	while (*argv) {
399 		/*
400 		 * ftp argv[0] is in the following format:
401 		 * ftpd: HOSTNAME: [USER/PASS: ]CMD args (ftpd)
402 		 */
403 		if (strncmp(*argv, "ftpd:", 5) == 0) {
404 			if ((str = strchr(*argv + 5, ':')) != NULL)
405 				str = strchr(str + 1, ':');
406 			if (str != NULL) {
407 				if ((str[0] == ':') &&
408 				    isspace((unsigned char)str[1]))
409 					str += 2;
410 				fmt_puts(str, &left);
411 			} else
412 				fmt_puts(*argv, &left);
413 		} else
414 			fmt_puts(*argv, &left);
415 		argv++;
416 		fmt_putc(' ', &left);
417 	}
418 	return;
419 nothing:
420 	putchar('-');
421 }
422 
423 static void
424 pr_header(time_t *nowp, int nusers)
425 {
426 	double avenrun[3];
427 	struct timespec boottime;
428 	time_t uptime;
429 	int days, hrs, i, mins;
430 	char buf[256];
431 
432 	/*
433 	 * Print time of day.
434 	 */
435 	(void)strftime(buf, sizeof(buf) - 1, "%l:%M%p", localtime(nowp));
436 	buf[sizeof(buf) - 1] = '\0';
437 	(void)printf("%s ", buf);
438 
439 	/*
440 	 * Print how long system has been up.
441 	 */
442 	if (clock_gettime(CLOCK_BOOTTIME, &boottime) != -1) {
443 		uptime = boottime.tv_sec;
444 		if (uptime > 59) {
445 			uptime += 30;
446 			days = uptime / SECSPERDAY;
447 			uptime %= SECSPERDAY;
448 			hrs = uptime / SECSPERHOUR;
449 			uptime %= SECSPERHOUR;
450 			mins = uptime / 60;
451 			(void)printf(" up");
452 			if (days > 0)
453 				(void)printf(" %d day%s,", days,
454 				    days > 1 ? "s" : "");
455 			if (hrs > 0 && mins > 0)
456 				(void)printf(" %2d:%02d,", hrs, mins);
457 			else {
458 				if (hrs > 0)
459 					(void)printf(" %d hr%s,",
460 					    hrs, hrs > 1 ? "s" : "");
461 				if (mins > 0 || (days == 0 && hrs == 0))
462 					(void)printf(" %d min%s,",
463 					    mins, mins != 1 ? "s" : "");
464 			}
465 		} else
466 			printf(" %d secs,", (int)uptime);
467 	}
468 
469 	/* Print number of users logged in to system */
470 	(void)printf(" %d user%s", nusers, nusers != 1 ? "s" : "");
471 
472 	/*
473 	 * Print 1, 5, and 15 minute load averages.
474 	 */
475 	if (getloadavg(avenrun, sizeof(avenrun) / sizeof(avenrun[0])) == -1)
476 		(void)printf(", no load average information available\n");
477 	else {
478 		(void)printf(", load averages:");
479 		for (i = 0; i < (sizeof(avenrun) / sizeof(avenrun[0])); i++) {
480 			if (i > 0)
481 				(void)printf(",");
482 			(void)printf(" %.2f", avenrun[i]);
483 		}
484 		(void)printf("\n");
485 	}
486 }
487 
488 static struct stat *
489 ttystat(char *line)
490 {
491 	static struct stat sb;
492 	char ttybuf[sizeof(_PATH_DEV) + UT_LINESIZE];
493 
494 	/* Note, line may not be NUL-terminated */
495 	(void)strlcpy(ttybuf, _PATH_DEV, sizeof(ttybuf));
496 	(void)strncat(ttybuf, line, sizeof(ttybuf) - 1 - strlen(ttybuf));
497 	if (stat(ttybuf, &sb))
498 		return (NULL);
499 	return (&sb);
500 }
501 
502 static void
503 usage(int wcmd)
504 {
505 	if (wcmd)
506 		(void)fprintf(stderr,
507 		    "usage: w [-ahi] [-M core] [-N system] [user]\n");
508 	else
509 		(void)fprintf(stderr,
510 		    "usage: uptime\n");
511 	exit (1);
512 }
513