xref: /dragonfly/usr.bin/last/last.c (revision 6e285212)
1 /*
2  * Copyright (c) 1987, 1993, 1994
3  *	The Regents of the University of California.  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  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * $FreeBSD: src/usr.bin/last/last.c,v 1.10.6.11 2002/11/02 23:00:26 mux Exp $
34  * $DragonFly: src/usr.bin/last/last.c,v 1.2 2003/06/17 04:29:27 dillon Exp $
35  *
36  * @(#) Copyright (c) 1987, 1993, 1994 The Regents of the University of California.  All rights reserved.
37  * @(#)last.c	8.2 (Berkeley) 4/2/94
38  */
39 
40 #include <sys/param.h>
41 #include <sys/stat.h>
42 
43 #include <err.h>
44 #include <fcntl.h>
45 #include <langinfo.h>
46 #include <locale.h>
47 #include <paths.h>
48 #include <signal.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <time.h>
53 #include <unistd.h>
54 #include <utmp.h>
55 #include <sys/queue.h>
56 
57 #define	NO	0				/* false/no */
58 #define	YES	1				/* true/yes */
59 #define	ATOI2(ar)	((ar)[0] - '0') * 10 + ((ar)[1] - '0'); (ar) += 2;
60 
61 static struct utmp	buf[1024];		/* utmp read buffer */
62 
63 typedef struct arg {
64 	char	*name;				/* argument */
65 #define	HOST_TYPE	-2
66 #define	TTY_TYPE	-3
67 #define	USER_TYPE	-4
68 	int	type;				/* type of arg */
69 	struct arg	*next;			/* linked list pointer */
70 } ARG;
71 ARG	*arglist;				/* head of linked list */
72 
73 LIST_HEAD(ttylisthead, ttytab) ttylist;
74 
75 struct ttytab {
76 	time_t	logout;				/* log out time */
77 	char	tty[UT_LINESIZE + 1];		/* terminal name */
78 	LIST_ENTRY(ttytab) list;
79 };
80 
81 static const	char *crmsg;			/* cause of last reboot */
82 static long	currentout,			/* current logout value */
83 		maxrec;				/* records to display */
84 static const	char *file = _PATH_WTMP;		/* wtmp file */
85 static int	sflag = 0;			/* show delta in seconds */
86 static int	width = 5;			/* show seconds in delta */
87 static int	yflag;				/* show year */
88 static int      d_first;
89 static int	snapfound = 0;			/* found snapshot entry? */
90 static time_t	snaptime;			/* if != 0, we will only
91 						 * report users logged in
92 						 * at this snapshot time
93 						 */
94 
95 int	 main __P((int, char *[]));
96 void	 addarg __P((int, char *));
97 time_t	 dateconv __P((char *));
98 void	 doentry __P((struct utmp *));
99 void	 hostconv __P((char *));
100 void	 onintr __P((int));
101 void	 printentry __P((struct utmp *, struct ttytab *));
102 char	*ttyconv __P((char *));
103 char	*ttyconv __P((char *));
104 int	 want __P((struct utmp *));
105 void	 usage __P((void));
106 void	 wtmp __P((void));
107 
108 void
109 usage(void)
110 {
111 	(void)fprintf(stderr,
112 "usage: last [-#] [-y] [-d [[CC]YY][MMDD]hhmm[.SS]] [-f file] [-h host]\n"
113 "\t[-t tty] [-s|w] [user ...]\n");
114 	exit(1);
115 }
116 
117 int
118 main(argc, argv)
119 	int argc;
120 	char *argv[];
121 {
122 	int ch;
123 	char *p;
124 
125 	(void) setlocale(LC_TIME, "");
126 	d_first = (*nl_langinfo(D_MD_ORDER) == 'd');
127 
128 	maxrec = -1;
129 	snaptime = 0;
130 	while ((ch = getopt(argc, argv, "0123456789d:f:h:st:wy")) != -1)
131 		switch (ch) {
132 		case '0': case '1': case '2': case '3': case '4':
133 		case '5': case '6': case '7': case '8': case '9':
134 			/*
135 			 * kludge: last was originally designed to take
136 			 * a number after a dash.
137 			 */
138 			if (maxrec == -1) {
139 				p = strchr(argv[optind - 1], ch);
140 				if (p == NULL)
141 					p = strchr(argv[optind], ch);
142 				maxrec = atol(p);
143 				if (!maxrec)
144 					exit(0);
145 			}
146 			break;
147 		case 'd':
148 			snaptime = dateconv(optarg);
149 			break;
150 		case 'f':
151 			file = optarg;
152 			break;
153 		case 'h':
154 			hostconv(optarg);
155 			addarg(HOST_TYPE, optarg);
156 			break;
157 		case 's':
158 			sflag++;	/* Show delta as seconds */
159 			break;
160 		case 't':
161 			addarg(TTY_TYPE, ttyconv(optarg));
162 			break;
163 		case 'w':
164 			width = 8;
165 			break;
166 		case 'y':
167 			yflag++;
168 			break;
169 		case '?':
170 		default:
171 			usage();
172 		}
173 
174 	if (sflag && width == 8) usage();
175 
176 	if (argc) {
177 		setlinebuf(stdout);
178 		for (argv += optind; *argv; ++argv) {
179 #define	COMPATIBILITY
180 #ifdef	COMPATIBILITY
181 			/* code to allow "last p5" to work */
182 			addarg(TTY_TYPE, ttyconv(*argv));
183 #endif
184 			addarg(USER_TYPE, *argv);
185 		}
186 	}
187 	wtmp();
188 	exit(0);
189 }
190 
191 /*
192  * wtmp --
193  *	read through the wtmp file
194  */
195 void
196 wtmp()
197 {
198 	struct utmp	*bp;			/* current structure */
199 	struct stat	stb;			/* stat of file for size */
200 	long	bl;
201 	int	bytes, wfd;
202 	char ct[80];
203 	struct tm *tm;
204 
205 	LIST_INIT(&ttylist);
206 
207 	if ((wfd = open(file, O_RDONLY, 0)) < 0 || fstat(wfd, &stb) == -1)
208 		err(1, "%s", file);
209 	bl = (stb.st_size + sizeof(buf) - 1) / sizeof(buf);
210 
211 	(void)time(&buf[0].ut_time);
212 	(void)signal(SIGINT, onintr);
213 	(void)signal(SIGQUIT, onintr);
214 
215 	while (--bl >= 0) {
216 		if (lseek(wfd, (off_t)(bl * sizeof(buf)), L_SET) == -1 ||
217 		    (bytes = read(wfd, buf, sizeof(buf))) == -1)
218 			err(1, "%s", file);
219 		for (bp = &buf[bytes / sizeof(buf[0]) - 1]; bp >= buf; --bp)
220 			doentry(bp);
221 	}
222 	tm = localtime(&buf[0].ut_time);
223 	(void) strftime(ct, sizeof(ct), "\nwtmp begins %+\n", tm);
224 	printf("%s", ct);
225 }
226 
227 /*
228  * doentry --
229  *	process a single wtmp entry
230  */
231 void
232 doentry(bp)
233 	struct utmp *bp;
234 {
235 	struct ttytab	*tt, *ttx;		/* ttylist entry */
236 
237 	/*
238 	 * if the terminal line is '~', the machine stopped.
239 	 * see utmp(5) for more info.
240 	 */
241 	if (bp->ut_line[0] == '~' && !bp->ut_line[1]) {
242 		/* everybody just logged out */
243 		for (tt = LIST_FIRST(&ttylist); tt;) {
244 			LIST_REMOVE(tt, list);
245 			ttx = tt;
246 			tt = LIST_NEXT(tt, list);
247 			free(ttx);
248 		}
249 		currentout = -bp->ut_time;
250 		crmsg = strncmp(bp->ut_name, "shutdown", UT_NAMESIZE) ?
251 		    "crash" : "shutdown";
252 		/*
253 		 * if we're in snapshot mode, we want to exit if this
254 		 * shutdown/reboot appears while we we are tracking the
255 		 * active range
256 		 */
257 		if (snaptime && snapfound)
258 			exit(0);
259 		/*
260 		 * don't print shutdown/reboot entries unless flagged for
261 		 */
262 		if (!snaptime && want(bp))
263 			printentry(bp, NULL);
264 		return;
265 	}
266 	/*
267 	 * if the line is '{' or '|', date got set; see
268 	 * utmp(5) for more info.
269 	 */
270 	if ((bp->ut_line[0] == '{' || bp->ut_line[0] == '|') &&
271 	    !bp->ut_line[1]) {
272 		if (want(bp) && !snaptime)
273 			printentry(bp, NULL);
274 		return;
275 	}
276 	/* find associated tty */
277 	LIST_FOREACH(tt, &ttylist, list)
278 	    if (!strncmp(tt->tty, bp->ut_line, UT_LINESIZE))
279 		    break;
280 
281 	if (tt == NULL) {
282 		/* add new one */
283 		tt = malloc(sizeof(struct ttytab));
284 		if (tt == NULL)
285 			err(1, "malloc failure");
286 		tt->logout = currentout;
287 		strncpy(tt->tty, bp->ut_line, UT_LINESIZE);
288 		LIST_INSERT_HEAD(&ttylist, tt, list);
289 	}
290 
291 	/*
292 	 * print record if not in snapshot mode and wanted
293 	 * or in snapshot mode and in snapshot range
294 	 */
295 	if (bp->ut_name[0] && (want(bp) || (bp->ut_time < snaptime &&
296 	    (tt->logout > snaptime || tt->logout < 1)))) {
297 		snapfound = 1;
298 		/*
299 		 * when uucp and ftp log in over a network, the entry in
300 		 * the utmp file is the name plus their process id.  See
301 		 * etc/ftpd.c and usr.bin/uucp/uucpd.c for more information.
302 		 */
303 		if (!strncmp(bp->ut_line, "ftp", sizeof("ftp") - 1))
304 			bp->ut_line[3] = '\0';
305 		else if (!strncmp(bp->ut_line, "uucp", sizeof("uucp") - 1))
306 			bp->ut_line[4] = '\0';
307 		printentry(bp, tt);
308 	}
309 	tt->logout = bp->ut_time;
310 }
311 
312 /*
313  * printentry --
314  *	output an entry
315  *
316  * If `tt' is non-NULL, use it and `crmsg' to print the logout time or
317  * logout type (crash/shutdown) as appropriate.
318  */
319 void
320 printentry(bp, tt)
321 	struct utmp *bp;
322 	struct ttytab *tt;
323 {
324 	char ct[80];
325 	struct tm *tm;
326 	time_t	delta;				/* time difference */
327 
328 	if (maxrec != -1 && !maxrec--)
329 		exit(0);
330 	tm = localtime(&bp->ut_time);
331 	(void) strftime(ct, sizeof(ct), d_first ?
332 	    (yflag ? "%a %e %b %Y %R" : "%a %e %b %R") :
333 	    (yflag ? "%a %b %e %Y %R" : "%a %b %e %R"), tm);
334 	printf("%-*.*s %-*.*s %-*.*s %s%c",
335 	    UT_NAMESIZE, UT_NAMESIZE, bp->ut_name,
336 	    UT_LINESIZE, UT_LINESIZE, bp->ut_line,
337 	    UT_HOSTSIZE, UT_HOSTSIZE, bp->ut_host,
338 	    ct, tt == NULL ? '\n' : ' ');
339 	if (tt == NULL)
340 		return;
341 	if (!tt->logout) {
342 		puts("  still logged in");
343 		return;
344 	}
345 	if (tt->logout < 0) {
346 		tt->logout = -tt->logout;
347 		printf("- %s", crmsg);
348 	} else {
349 		tm = localtime(&tt->logout);
350 		(void) strftime(ct, sizeof(ct), "%R", tm);
351 		printf("- %s", ct);
352 	}
353 	delta = tt->logout - bp->ut_time;
354 	if (sflag) {
355 		printf("  (%8ld)\n", (long)delta);
356 	} else {
357 		tm = gmtime(&delta);
358 		(void) strftime(ct, sizeof(ct), width >= 8 ? "%T" : "%R", tm);
359 		if (delta < 86400)
360 			printf("  (%s)\n", ct);
361 		else
362 			printf(" (%ld+%s)\n", (long)delta / 86400, ct);
363 	}
364 }
365 
366 /*
367  * want --
368  *	see if want this entry
369  */
370 int
371 want(bp)
372 	struct utmp *bp;
373 {
374 	ARG *step;
375 
376 	if (snaptime)
377 		return (NO);
378 
379 	if (!arglist)
380 		return (YES);
381 
382 	for (step = arglist; step; step = step->next)
383 		switch(step->type) {
384 		case HOST_TYPE:
385 			if (!strncasecmp(step->name, bp->ut_host, UT_HOSTSIZE))
386 				return (YES);
387 			break;
388 		case TTY_TYPE:
389 			if (!strncmp(step->name, bp->ut_line, UT_LINESIZE))
390 				return (YES);
391 			break;
392 		case USER_TYPE:
393 			if (!strncmp(step->name, bp->ut_name, UT_NAMESIZE))
394 				return (YES);
395 			break;
396 		}
397 	return (NO);
398 }
399 
400 /*
401  * addarg --
402  *	add an entry to a linked list of arguments
403  */
404 void
405 addarg(type, arg)
406 	int type;
407 	char *arg;
408 {
409 	ARG *cur;
410 
411 	if (!(cur = (ARG *)malloc((u_int)sizeof(ARG))))
412 		err(1, "malloc failure");
413 	cur->next = arglist;
414 	cur->type = type;
415 	cur->name = arg;
416 	arglist = cur;
417 }
418 
419 /*
420  * hostconv --
421  *	convert the hostname to search pattern; if the supplied host name
422  *	has a domain attached that is the same as the current domain, rip
423  *	off the domain suffix since that's what login(1) does.
424  */
425 void
426 hostconv(arg)
427 	char *arg;
428 {
429 	static int first = 1;
430 	static char *hostdot, name[MAXHOSTNAMELEN];
431 	char *argdot;
432 
433 	if (!(argdot = strchr(arg, '.')))
434 		return;
435 	if (first) {
436 		first = 0;
437 		if (gethostname(name, sizeof(name)))
438 			err(1, "gethostname");
439 		hostdot = strchr(name, '.');
440 	}
441 	if (hostdot && !strcasecmp(hostdot, argdot))
442 		*argdot = '\0';
443 }
444 
445 /*
446  * ttyconv --
447  *	convert tty to correct name.
448  */
449 char *
450 ttyconv(arg)
451 	char *arg;
452 {
453 	char *mval;
454 
455 	/*
456 	 * kludge -- we assume that all tty's end with
457 	 * a two character suffix.
458 	 */
459 	if (strlen(arg) == 2) {
460 		/* either 6 for "ttyxx" or 8 for "console" */
461 		if (!(mval = malloc((u_int)8)))
462 			err(1, "malloc failure");
463 		if (!strcmp(arg, "co"))
464 			(void)strcpy(mval, "console");
465 		else {
466 			(void)strcpy(mval, "tty");
467 			(void)strcpy(mval + 3, arg);
468 		}
469 		return (mval);
470 	}
471 	if (!strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1))
472 		return (arg + 5);
473 	return (arg);
474 }
475 
476 /*
477  * dateconv --
478  * 	Convert the snapshot time in command line given in the format
479  * 	[[CC]YY]MMDDhhmm[.SS]] to a time_t.
480  * 	Derived from atime_arg1() in usr.bin/touch/touch.c
481  */
482 time_t
483 dateconv(arg)
484         char *arg;
485 {
486         time_t timet;
487         struct tm *t;
488         int yearset;
489         char *p;
490 
491         /* Start with the current time. */
492         if (time(&timet) < 0)
493                 err(1, "time");
494         if ((t = localtime(&timet)) == NULL)
495                 err(1, "localtime");
496 
497         /* [[CC]YY]MMDDhhmm[.SS] */
498         if ((p = strchr(arg, '.')) == NULL)
499                 t->tm_sec = 0; 		/* Seconds defaults to 0. */
500         else {
501                 if (strlen(p + 1) != 2)
502                         goto terr;
503                 *p++ = '\0';
504                 t->tm_sec = ATOI2(p);
505         }
506 
507         yearset = 0;
508         switch (strlen(arg)) {
509         case 12:                	/* CCYYMMDDhhmm */
510                 t->tm_year = ATOI2(arg);
511                 t->tm_year *= 100;
512                 yearset = 1;
513                 /* FALLTHOUGH */
514         case 10:                	/* YYMMDDhhmm */
515                 if (yearset) {
516                         yearset = ATOI2(arg);
517                         t->tm_year += yearset;
518                 } else {
519                         yearset = ATOI2(arg);
520                         if (yearset < 69)
521                                 t->tm_year = yearset + 2000;
522                         else
523                                 t->tm_year = yearset + 1900;
524                 }
525                 t->tm_year -= 1900;     /* Convert to UNIX time. */
526                 /* FALLTHROUGH */
527         case 8:				/* MMDDhhmm */
528                 t->tm_mon = ATOI2(arg);
529                 --t->tm_mon;    	/* Convert from 01-12 to 00-11 */
530                 t->tm_mday = ATOI2(arg);
531                 t->tm_hour = ATOI2(arg);
532                 t->tm_min = ATOI2(arg);
533                 break;
534         case 4:				/* hhmm */
535                 t->tm_hour = ATOI2(arg);
536                 t->tm_min = ATOI2(arg);
537                 break;
538         default:
539                 goto terr;
540         }
541         t->tm_isdst = -1;       	/* Figure out DST. */
542         timet = mktime(t);
543         if (timet == -1)
544 terr:           errx(1,
545         "out of range or illegal time specification: [[CC]YY]MMDDhhmm[.SS]");
546         return timet;
547 }
548 
549 
550 /*
551  * onintr --
552  *	on interrupt, we inform the user how far we've gotten
553  */
554 void
555 onintr(signo)
556 	int signo;
557 {
558 	char ct[80];
559 	struct tm *tm;
560 
561 	tm = localtime(&buf[0].ut_time);
562 	(void) strftime(ct, sizeof(ct),
563 			d_first ? "%a %e %b %R" : "%a %b %e %R",
564 			tm);
565 	printf("\ninterrupted %s\n", ct);
566 	if (signo == SIGINT)
567 		exit(1);
568 	(void)fflush(stdout);			/* fix required for rsh */
569 }
570