xref: /openbsd/usr.bin/w/w.c (revision 6b78bc15)
1 /*	$OpenBSD: w.c,v 1.64 2017/12/14 18:03:03 jasper 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/param.h>	/* MAXCOMLEN */
39 #include <sys/time.h>
40 #include <sys/stat.h>
41 #include <sys/sysctl.h>
42 #include <sys/signal.h>
43 #include <sys/proc.h>
44 #include <sys/ioctl.h>
45 #include <sys/socket.h>
46 #include <sys/tty.h>
47 
48 #include <netinet/in.h>
49 #include <arpa/inet.h>
50 
51 #include <ctype.h>
52 #include <err.h>
53 #include <errno.h>
54 #include <fcntl.h>
55 #include <kvm.h>
56 #include <netdb.h>
57 #include <nlist.h>
58 #include <paths.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <unistd.h>
63 #include <limits.h>
64 #include <utmp.h>
65 #include <vis.h>
66 
67 #include "extern.h"
68 
69 struct timeval	boottime;
70 struct utmp	utmp;
71 struct winsize	ws;
72 kvm_t	       *kd;
73 time_t		now;		/* the current time of day */
74 int		ttywidth;	/* width of tty */
75 int		argwidth;	/* width of tty */
76 int		header = 1;	/* true if -h flag: don't print heading */
77 int		nflag = 1;	/* true if -n flag: don't convert addrs */
78 int		sortidle;	/* sort by idle time */
79 char	       *sel_user;	/* login of particular user selected */
80 char		domain[HOST_NAME_MAX+1];
81 
82 #define	NAME_WIDTH	8
83 #define HOST_WIDTH	16
84 
85 /*
86  * One of these per active utmp entry.
87  */
88 struct	entry {
89 	struct	entry *next;
90 	struct	utmp utmp;
91 	dev_t	tdev;			/* dev_t of terminal */
92 	time_t	idle;			/* idle time of terminal in seconds */
93 	struct	kinfo_proc *kp;		/* `most interesting' proc */
94 } *ep, *ehead = NULL, **nextp = &ehead;
95 
96 static void	 fmt_putc(int, int *);
97 static void	 fmt_puts(const char *, int *);
98 static void	 pr_args(struct kinfo_proc *);
99 static void	 pr_header(time_t *, int);
100 static struct stat
101 		*ttystat(char *);
102 static void	 usage(int);
103 
104 int
105 main(int argc, char *argv[])
106 {
107 	extern char *__progname;
108 	struct kinfo_proc *kp;
109 	struct hostent *hp;
110 	struct stat *stp;
111 	FILE *ut;
112 	struct in_addr addr;
113 	int ch, i, nentries, nusers, wcmd;
114 	char *memf, *nlistf, *p, *x;
115 	char buf[HOST_NAME_MAX+1], errbuf[_POSIX2_LINE_MAX];
116 
117 	/* Are we w(1) or uptime(1)? */
118 	p = __progname;
119 	if (*p == '-')
120 		p++;
121 	if (p[0] == 'w' && p[1] == '\0') {
122 		wcmd = 1;
123 		p = "hiflM:N:asuw";
124 	} else if (!strcmp(p, "uptime")) {
125 		wcmd = 0;
126 		p = "";
127 	} else
128 		errx(1,
129 		 "this program should be invoked only as \"w\" or \"uptime\"");
130 
131 	memf = nlistf = NULL;
132 	while ((ch = getopt(argc, argv, p)) != -1)
133 		switch (ch) {
134 		case 'h':
135 			header = 0;
136 			break;
137 		case 'i':
138 			sortidle = 1;
139 			break;
140 		case 'M':
141 			header = 0;
142 			memf = optarg;
143 			break;
144 		case 'N':
145 			nlistf = optarg;
146 			break;
147 		case 'a':
148 			nflag = 0;
149 			break;
150 		case 'f': case 'l': case 's': case 'u': case 'w':
151 			warnx("[-flsuw] no longer supported");
152 			/* FALLTHROUGH */
153 		case '?':
154 		default:
155 			usage(wcmd);
156 		}
157 	argc -= optind;
158 	argv += optind;
159 
160 	if (nflag == 0) {
161 		if (pledge("stdio tty rpath dns ps vminfo", NULL) == -1)
162 			err(1, "pledge");
163 	} else {
164 		if (pledge("stdio tty rpath ps vminfo", NULL) == -1)
165 			err(1, "pledge");
166 	}
167 
168 	if (nlistf == NULL && memf == NULL) {
169 		if ((kd = kvm_openfiles(nlistf, memf, NULL, KVM_NO_FILES,
170 		    errbuf)) == NULL)
171 			errx(1, "%s", errbuf);
172 	} else {
173 		if ((kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf)) == NULL)
174 			errx(1, "%s", errbuf);
175 	}
176 
177 	(void)time(&now);
178 	if ((ut = fopen(_PATH_UTMP, "r")) == NULL)
179 		err(1, "%s", _PATH_UTMP);
180 
181 	if (*argv)
182 		sel_user = *argv;
183 
184 	for (nusers = 0; fread(&utmp, sizeof(utmp), 1, ut);) {
185 		if (utmp.ut_name[0] == '\0')
186 			continue;
187 		++nusers;
188 		if (wcmd == 0 || (sel_user &&
189 		    strncmp(utmp.ut_name, sel_user, UT_NAMESIZE) != 0))
190 			continue;
191 		if ((ep = calloc(1, sizeof(*ep))) == NULL)
192 			err(1, NULL);
193 		*nextp = ep;
194 		nextp = &(ep->next);
195 		memcpy(&(ep->utmp), &utmp, sizeof(utmp));
196 		if (!(stp = ttystat(ep->utmp.ut_line)))
197 			continue;
198 		ep->tdev = stp->st_rdev;
199 
200 		/*
201 		 * If this is the console device, attempt to ascertain
202 		 * the true console device dev_t.
203 		 */
204 		if (ep->tdev == 0) {
205 			int mib[2];
206 			size_t size;
207 
208 			mib[0] = CTL_KERN;
209 			mib[1] = KERN_CONSDEV;
210 			size = sizeof(dev_t);
211 			(void) sysctl(mib, 2, &ep->tdev, &size, NULL, 0);
212 		}
213 
214 		if ((ep->idle = now - stp->st_atime) < 0)
215 			ep->idle = 0;
216 	}
217 	(void)fclose(ut);
218 
219 	if (header || wcmd == 0) {
220 		pr_header(&now, nusers);
221 		if (wcmd == 0)
222 			exit (0);
223 	}
224 
225 #define HEADER	"USER    TTY FROM              LOGIN@  IDLE WHAT"
226 #define WUSED	(sizeof(HEADER) - sizeof("WHAT"))
227 	if (header)
228 		(void)puts(HEADER);
229 
230 	kp = kvm_getprocs(kd, KERN_PROC_ALL, 0, sizeof(*kp), &nentries);
231 	if (kp == NULL)
232 		errx(1, "%s", kvm_geterr(kd));
233 
234 	if ((ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) == -1 &&
235 	    ioctl(STDERR_FILENO, TIOCGWINSZ, &ws) == -1 &&
236 	    ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) == -1) || ws.ws_col == 0)
237 		ttywidth = 79;
238 	else
239 		ttywidth = ws.ws_col - 1;
240 	argwidth = ttywidth - WUSED;
241 	if (argwidth < 4)
242 		argwidth = 8;
243 
244 	for (i = 0; i < nentries; i++, kp++) {
245 		if (kp->p_psflags & (PS_EMBRYO | PS_ZOMBIE))
246 			continue;
247 		for (ep = ehead; ep != NULL; ep = ep->next) {
248 			/* ftp is a special case. */
249 			if (strncmp(ep->utmp.ut_line, "ftp", 3) == 0) {
250 				char pidstr[UT_LINESIZE-2];
251 				pid_t fp;
252 
253 				(void)strncpy(pidstr, &ep->utmp.ut_line[3],
254 				    sizeof(pidstr) - 1);
255 				pidstr[sizeof(pidstr) - 1] = '\0';
256 				fp = (pid_t)strtol(pidstr, NULL, 10);
257 				if (kp->p_pid == fp) {
258 					ep->kp = kp;
259 					break;
260 				}
261 			} else if (ep->tdev == kp->p_tdev &&
262 			    kp->p__pgid == kp->p_tpgid) {
263 				/*
264 				 * Proc is in foreground of this terminal
265 				 */
266 				if (proc_compare(ep->kp, kp))
267 					ep->kp = kp;
268 				break;
269 			}
270 		}
271 	}
272 	/* sort by idle time */
273 	if (sortidle && ehead != NULL) {
274 		struct entry *from = ehead, *save;
275 
276 		ehead = NULL;
277 		while (from != NULL) {
278 			for (nextp = &ehead;
279 			    (*nextp) && from->idle >= (*nextp)->idle;
280 			    nextp = &(*nextp)->next)
281 				continue;
282 			save = from;
283 			from = from->next;
284 			save->next = *nextp;
285 			*nextp = save;
286 		}
287 	}
288 
289 	if (!nflag) {
290 		if (gethostname(domain, sizeof(domain)) < 0 ||
291 		    (p = strchr(domain, '.')) == 0)
292 			domain[0] = '\0';
293 		else {
294 			domain[sizeof(domain) - 1] = '\0';
295 			memmove(domain, p, strlen(p) + 1);
296 		}
297 	}
298 
299 	for (ep = ehead; ep != NULL; ep = ep->next) {
300 		p = *ep->utmp.ut_host ? ep->utmp.ut_host : "-";
301 		for (x = NULL, i = 0; p[i] != '\0' && i < UT_HOSTSIZE; i++)
302 			if (p[i] == ':') {
303 				x = &p[i];
304 				*x++ = '\0';
305 				break;
306 			}
307 		if (!nflag && inet_aton(p, &addr) &&
308 		    (hp = gethostbyaddr((char *)&addr, sizeof(addr), AF_INET))) {
309 			if (domain[0] != '\0') {
310 				p = hp->h_name;
311 				p += strlen(hp->h_name);
312 				p -= strlen(domain);
313 				if (p > hp->h_name &&
314 				    strcasecmp(p, domain) == 0)
315 					*p = '\0';
316 			}
317 			p = hp->h_name;
318 		}
319 		if (x) {
320 			(void)snprintf(buf, sizeof(buf), "%s:%.*s", p,
321 			    (int)(ep->utmp.ut_host + UT_HOSTSIZE - x), x);
322 			p = buf;
323 		}
324 		(void)printf("%-*.*s %-2.2s %-*.*s ",
325 		    NAME_WIDTH, UT_NAMESIZE, ep->utmp.ut_name,
326 		    strncmp(ep->utmp.ut_line, "tty", 3) ?
327 		    ep->utmp.ut_line : ep->utmp.ut_line + 3,
328 		    HOST_WIDTH, HOST_WIDTH, *p ? p : "-");
329 		pr_attime(&ep->utmp.ut_time, &now);
330 		pr_idle(ep->idle);
331 		pr_args(ep->kp);
332 		printf("\n");
333 	}
334 	exit(0);
335 }
336 
337 static void
338 fmt_putc(int c, int *leftp)
339 {
340 
341 	if (*leftp == 0)
342 		return;
343 	if (*leftp != -1)
344 		*leftp -= 1;
345 	putchar(c);
346 }
347 
348 static void
349 fmt_puts(const char *s, int *leftp)
350 {
351 	static char *v = NULL;
352 	static size_t maxlen = 0;
353 	size_t len;
354 
355 	if (*leftp == 0)
356 		return;
357 	len = strlen(s) * 4 + 1;
358 	if (len > maxlen) {
359 		free(v);
360 		maxlen = 0;
361 		if (len < getpagesize())
362 			len = getpagesize();
363 		v = malloc(len);
364 		if (v == NULL)
365 			return;
366 		maxlen = len;
367 	}
368 	strvis(v, s, VIS_TAB | VIS_NL | VIS_CSTYLE);
369 	if (*leftp != -1) {
370 		len = strlen(v);
371 		if (len > *leftp) {
372 			v[*leftp] = '\0';
373 			*leftp = 0;
374 		} else
375 			*leftp -= len;
376 	}
377 	printf("%s", v);
378 }
379 
380 
381 static void
382 pr_args(struct kinfo_proc *kp)
383 {
384 	char **argv, *str;
385 	int left;
386 
387 	if (kp == NULL)
388 		goto nothing;		/* no matching process found */
389 	left = argwidth;
390 	argv = kvm_getargv(kd, kp, argwidth+60);  /* +60 for ftpd snip */
391 	if (argv == NULL)
392 		goto nothing;
393 
394 	if (*argv == NULL || **argv == '\0') {
395 		/* Process has zeroed argv[0], display executable name. */
396 		fmt_putc('(', &left);
397 		fmt_puts(kp->p_comm, &left);
398 		fmt_putc(')', &left);
399 	}
400 	while (*argv) {
401 		/*
402 		 * ftp argv[0] is in the following format:
403 		 * ftpd: HOSTNAME: [USER/PASS: ]CMD args (ftpd)
404 		 */
405 		if (strncmp(*argv, "ftpd:", 5) == 0) {
406 			if ((str = strchr(*argv + 5, ':')) != NULL)
407 				str = strchr(str + 1, ':');
408 			if (str != NULL) {
409 				if ((str[0] == ':') &&
410 				    isspace((unsigned char)str[1]))
411 					str += 2;
412 				fmt_puts(str, &left);
413 			} else
414 				fmt_puts(*argv, &left);
415 		} else
416 			fmt_puts(*argv, &left);
417 		argv++;
418 		fmt_putc(' ', &left);
419 	}
420 	return;
421 nothing:
422 	putchar('-');
423 }
424 
425 static void
426 pr_header(time_t *nowp, int nusers)
427 {
428 	double avenrun[3];
429 	time_t uptime;
430 	int days, hrs, i, mins;
431 	int mib[2];
432 	size_t size;
433 	char buf[256];
434 
435 	/*
436 	 * Print time of day.
437 	 */
438 	(void)strftime(buf, sizeof(buf) - 1, "%l:%M%p", localtime(nowp));
439 	buf[sizeof(buf) - 1] = '\0';
440 	(void)printf("%s ", buf);
441 
442 	/*
443 	 * Print how long system has been up.
444 	 * (Found by getting "boottime" from the kernel)
445 	 */
446 	mib[0] = CTL_KERN;
447 	mib[1] = KERN_BOOTTIME;
448 	size = sizeof(boottime);
449 	if (sysctl(mib, 2, &boottime, &size, NULL, 0) != -1) {
450 		uptime = now - boottime.tv_sec;
451 		if (uptime > 59) {
452 			uptime += 30;
453 			days = uptime / SECSPERDAY;
454 			uptime %= SECSPERDAY;
455 			hrs = uptime / SECSPERHOUR;
456 			uptime %= SECSPERHOUR;
457 			mins = uptime / 60;
458 			(void)printf(" up");
459 			if (days > 0)
460 				(void)printf(" %d day%s,", days,
461 				    days > 1 ? "s" : "");
462 			if (hrs > 0 && mins > 0)
463 				(void)printf(" %2d:%02d,", hrs, mins);
464 			else {
465 				if (hrs > 0)
466 					(void)printf(" %d hr%s,",
467 					    hrs, hrs > 1 ? "s" : "");
468 				if (mins > 0 || (days == 0 && hrs == 0))
469 					(void)printf(" %d min%s,",
470 					    mins, mins != 1 ? "s" : "");
471 			}
472 		} else
473 			printf(" %d secs,", (int)uptime);
474 	}
475 
476 	/* Print number of users logged in to system */
477 	(void)printf(" %d user%s", nusers, nusers != 1 ? "s" : "");
478 
479 	/*
480 	 * Print 1, 5, and 15 minute load averages.
481 	 */
482 	if (getloadavg(avenrun, sizeof(avenrun) / sizeof(avenrun[0])) == -1)
483 		(void)printf(", no load average information available\n");
484 	else {
485 		(void)printf(", load averages:");
486 		for (i = 0; i < (sizeof(avenrun) / sizeof(avenrun[0])); i++) {
487 			if (i > 0)
488 				(void)printf(",");
489 			(void)printf(" %.2f", avenrun[i]);
490 		}
491 		(void)printf("\n");
492 	}
493 }
494 
495 static struct stat *
496 ttystat(char *line)
497 {
498 	static struct stat sb;
499 	char ttybuf[sizeof(_PATH_DEV) + UT_LINESIZE];
500 
501 	/* Note, line may not be NUL-terminated */
502 	(void)strlcpy(ttybuf, _PATH_DEV, sizeof(ttybuf));
503 	(void)strncat(ttybuf, line, sizeof(ttybuf) - 1 - strlen(ttybuf));
504 	if (stat(ttybuf, &sb))
505 		return (NULL);
506 	return (&sb);
507 }
508 
509 static void
510 usage(int wcmd)
511 {
512 	if (wcmd)
513 		(void)fprintf(stderr,
514 		    "usage: w [-ahi] [-M core] [-N system] [user]\n");
515 	else
516 		(void)fprintf(stderr,
517 		    "usage: uptime\n");
518 	exit (1);
519 }
520