Home | History | Annotate | Line # | Download | only in last
last.c revision 1.9
      1 /*	$NetBSD: last.c,v 1.9 1997/08/26 18:52:13 thorpej Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1987, 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. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #ifndef lint
     38 __COPYRIGHT(
     39 "@(#) Copyright (c) 1987, 1993, 1994\n\
     40 	The Regents of the University of California.  All rights reserved.\n");
     41 #endif /* not lint */
     42 
     43 #ifndef lint
     44 #if 0
     45 static char sccsid[] = "@(#)last.c	8.2 (Berkeley) 4/2/94";
     46 #endif
     47 __RCSID("$NetBSD: last.c,v 1.9 1997/08/26 18:52:13 thorpej Exp $");
     48 #endif /* not lint */
     49 
     50 #include <sys/param.h>
     51 #include <sys/stat.h>
     52 
     53 #include <err.h>
     54 #include <fcntl.h>
     55 #include <paths.h>
     56 #include <signal.h>
     57 #include <stdio.h>
     58 #include <stdlib.h>
     59 #include <string.h>
     60 #include <time.h>
     61 #include <tzfile.h>
     62 #include <unistd.h>
     63 #include <utmp.h>
     64 
     65 #define	NO	0				/* false/no */
     66 #define	YES	1				/* true/yes */
     67 
     68 static struct utmp	buf[1024];		/* utmp read buffer */
     69 
     70 typedef struct arg {
     71 	char	*name;				/* argument */
     72 #define	HOST_TYPE	-2
     73 #define	TTY_TYPE	-3
     74 #define	USER_TYPE	-4
     75 	int	type;				/* type of arg */
     76 	struct arg	*next;			/* linked list pointer */
     77 } ARG;
     78 ARG	*arglist;				/* head of linked list */
     79 
     80 typedef struct ttytab {
     81 	time_t	logout;				/* log out time */
     82 	char	tty[UT_LINESIZE + 1];		/* terminal name */
     83 	struct ttytab	*next;			/* linked list pointer */
     84 } TTY;
     85 TTY	*ttylist;				/* head of linked list */
     86 
     87 static time_t	currentout;			/* current logout value */
     88 static long	maxrec;				/* records to display */
     89 static char	*file = _PATH_WTMP;		/* wtmp file */
     90 static int	fulltime = 0;                   /* Display seconds? */
     91 
     92 int	 main __P((int, char *[]));
     93 void	 addarg __P((int, char *));
     94 TTY	*addtty __P((char *));
     95 void	 hostconv __P((char *));
     96 void	 onintr __P((int));
     97 char	*ttyconv __P((char *));
     98 int	 want __P((struct utmp *, int));
     99 void	 wtmp __P((void));
    100 
    101 int
    102 main(argc, argv)
    103 	int argc;
    104 	char *argv[];
    105 {
    106 	extern int optind;
    107 	extern char *optarg;
    108 	int ch;
    109 	char *p;
    110 
    111 	maxrec = -1;
    112 	while ((ch = getopt(argc, argv, "0123456789f:h:t:T")) != -1)
    113 		switch (ch) {
    114 		case '0': case '1': case '2': case '3': case '4':
    115 		case '5': case '6': case '7': case '8': case '9':
    116 			/*
    117 			 * kludge: last was originally designed to take
    118 			 * a number after a dash.
    119 			 */
    120 			if (maxrec == -1) {
    121 				p = argv[optind - 1];
    122 				if (p[0] == '-' && p[1] == ch && !p[2])
    123 					maxrec = atol(++p);
    124 				else
    125 					maxrec = atol(argv[optind] + 1);
    126 				if (!maxrec)
    127 					exit(0);
    128 			}
    129 			break;
    130 		case 'f':
    131 			file = optarg;
    132 			break;
    133 		case 'h':
    134 			hostconv(optarg);
    135 			addarg(HOST_TYPE, optarg);
    136 			break;
    137 		case 't':
    138 			addarg(TTY_TYPE, ttyconv(optarg));
    139 			break;
    140 		case 'T':
    141 			fulltime = 1;
    142 			break;
    143 		case '?':
    144 		default:
    145 			(void)fprintf(stderr,
    146 	"usage: last [-#] [-f file] [-t tty] [-h hostname] [-T] [user ...]\n");
    147 			exit(1);
    148 		}
    149 
    150 	if (argc) {
    151 		setlinebuf(stdout);
    152 		for (argv += optind; *argv; ++argv) {
    153 #define	COMPATIBILITY
    154 #ifdef	COMPATIBILITY
    155 			/* code to allow "last p5" to work */
    156 			addarg(TTY_TYPE, ttyconv(*argv));
    157 #endif
    158 			addarg(USER_TYPE, *argv);
    159 		}
    160 	}
    161 	wtmp();
    162 	exit(0);
    163 }
    164 
    165 /*
    166  * wtmp --
    167  *	read through the wtmp file
    168  */
    169 void
    170 wtmp()
    171 {
    172 	struct utmp	*bp;		/* current structure */
    173 	TTY	*T;			/* tty list entry */
    174 	struct stat	stb;		/* stat of file for size */
    175 	time_t	delta;			/* time difference */
    176 	off_t	bl;
    177 	int	timesize;		/* how much of time string to print */
    178 	int	bytes, wfd;
    179 	char	*ct, *crmsg;
    180 
    181 	crmsg = NULL;
    182 
    183 	if ((wfd = open(file, O_RDONLY, 0)) < 0 || fstat(wfd, &stb) == -1)
    184 		err(1, "%s", file);
    185 	bl = (stb.st_size + sizeof(buf) - 1) / sizeof(buf);
    186 
    187 	if (fulltime)
    188 		timesize = 8;	/* HH:MM:SS */
    189 	else
    190 		timesize = 5;	/* HH:MM */
    191 
    192 	(void)time(&buf[0].ut_time);
    193 	(void)signal(SIGINT, onintr);
    194 	(void)signal(SIGQUIT, onintr);
    195 
    196 	while (--bl >= 0) {
    197 		if (lseek(wfd, bl * sizeof(buf), SEEK_SET) == -1 ||
    198 		    (bytes = read(wfd, buf, sizeof(buf))) == -1)
    199 			err(1, "%s", file);
    200 		for (bp = &buf[bytes / sizeof(buf[0]) - 1]; bp >= buf; --bp) {
    201 			/*
    202 			 * if the terminal line is '~', the machine stopped.
    203 			 * see utmp(5) for more info.
    204 			 */
    205 			if (bp->ut_line[0] == '~' && !bp->ut_line[1]) {
    206 				/* everybody just logged out */
    207 				for (T = ttylist; T; T = T->next)
    208 					T->logout = -bp->ut_time;
    209 				currentout = -bp->ut_time;
    210 				crmsg = strncmp(bp->ut_name, "shutdown",
    211 				    UT_NAMESIZE) ? "crash" : "shutdown";
    212 				if (want(bp, NO)) {
    213 					ct = ctime(&bp->ut_time);
    214 				printf("%-*.*s  %-*.*s %-*.*s %10.10s %*.*s \n",
    215 					    UT_NAMESIZE, UT_NAMESIZE,
    216 					    bp->ut_name, UT_LINESIZE,
    217 					    UT_LINESIZE, bp->ut_line,
    218 					    UT_HOSTSIZE, UT_HOSTSIZE,
    219 					    bp->ut_host, ct, timesize,
    220 				            timesize, ct + 11);
    221 					if (maxrec != -1 && !--maxrec)
    222 						return;
    223 				}
    224 				continue;
    225 			}
    226 			/*
    227 			 * if the line is '{' or '|', date got set; see
    228 			 * utmp(5) for more info.
    229 			 */
    230 			if ((bp->ut_line[0] == '{' || bp->ut_line[0] == '|')
    231 			    && !bp->ut_line[1]) {
    232 				if (want(bp, NO)) {
    233 					ct = ctime(&bp->ut_time);
    234 				printf("%-*.*s  %-*.*s %-*.*s %10.10s %*.*s \n",
    235 				    UT_NAMESIZE, UT_NAMESIZE, bp->ut_name,
    236 				    UT_LINESIZE, UT_LINESIZE, bp->ut_line,
    237 				    UT_HOSTSIZE, UT_HOSTSIZE, bp->ut_host,
    238 				    ct, timesize, timesize, ct + 11);
    239 					if (maxrec && !--maxrec)
    240 						return;
    241 				}
    242 				continue;
    243 			}
    244 			/* find associated tty */
    245 			for (T = ttylist;; T = T->next) {
    246 				if (!T) {
    247 					/* add new one */
    248 					T = addtty(bp->ut_line);
    249 					break;
    250 				}
    251 				if (!strncmp(T->tty, bp->ut_line, UT_LINESIZE))
    252 					break;
    253 			}
    254 			if (bp->ut_name[0] && want(bp, YES)) {
    255 				ct = ctime(&bp->ut_time);
    256 				printf("%-*.*s  %-*.*s %-*.*s %10.10s %*.*s ",
    257 				UT_NAMESIZE, UT_NAMESIZE, bp->ut_name,
    258 				UT_LINESIZE, UT_LINESIZE, bp->ut_line,
    259 				UT_HOSTSIZE, UT_HOSTSIZE, bp->ut_host,
    260 				ct, timesize, timesize, ct + 11);
    261 				if (!T->logout)
    262 					puts("  still logged in");
    263 				else {
    264 					if (T->logout < 0) {
    265 						T->logout = -T->logout;
    266 						printf("- %s", crmsg);
    267 					}
    268 					else
    269 						printf("- %*.*s",
    270 						    timesize, timesize,
    271 						    ctime(&T->logout)+11);
    272 					delta = T->logout - bp->ut_time;
    273 					if (delta < SECSPERDAY)
    274 						printf("  (%*.*s)\n",
    275 						    timesize, timesize,
    276 						    asctime(gmtime(&delta))+11);
    277 					else
    278 						printf(" (%ld+%*.*s)\n",
    279 						    delta / SECSPERDAY,
    280 						    timesize, timesize,
    281 						    asctime(gmtime(&delta))+11);
    282 				}
    283 				if (maxrec != -1 && !--maxrec)
    284 					return;
    285 			}
    286 			T->logout = bp->ut_time;
    287 		}
    288 	}
    289 	ct = ctime(&buf[0].ut_time);
    290 	printf("\nwtmp begins %10.10s %*.*s \n", ct, timesize, timesize, ct + 11);
    291 }
    292 
    293 /*
    294  * want --
    295  *	see if want this entry
    296  */
    297 int
    298 want(bp, check)
    299 	struct utmp *bp;
    300 	int check;
    301 {
    302 	ARG *step;
    303 
    304 	if (check)
    305 		/*
    306 		 * when uucp and ftp log in over a network, the entry in
    307 		 * the utmp file is the name plus their process id.  See
    308 		 * etc/ftpd.c and usr.bin/uucp/uucpd.c for more information.
    309 		 */
    310 		if (!strncmp(bp->ut_line, "ftp", sizeof("ftp") - 1))
    311 			bp->ut_line[3] = '\0';
    312 		else if (!strncmp(bp->ut_line, "uucp", sizeof("uucp") - 1))
    313 			bp->ut_line[4] = '\0';
    314 	if (!arglist)
    315 		return (YES);
    316 
    317 	for (step = arglist; step; step = step->next)
    318 		switch(step->type) {
    319 		case HOST_TYPE:
    320 			if (!strncasecmp(step->name, bp->ut_host, UT_HOSTSIZE))
    321 				return (YES);
    322 			break;
    323 		case TTY_TYPE:
    324 			if (!strncmp(step->name, bp->ut_line, UT_LINESIZE))
    325 				return (YES);
    326 			break;
    327 		case USER_TYPE:
    328 			if (!strncmp(step->name, bp->ut_name, UT_NAMESIZE))
    329 				return (YES);
    330 			break;
    331 	}
    332 	return (NO);
    333 }
    334 
    335 /*
    336  * addarg --
    337  *	add an entry to a linked list of arguments
    338  */
    339 void
    340 addarg(type, arg)
    341 	int type;
    342 	char *arg;
    343 {
    344 	ARG *cur;
    345 
    346 	if (!(cur = (ARG *)malloc((u_int)sizeof(ARG))))
    347 		err(1, "malloc failure");
    348 	cur->next = arglist;
    349 	cur->type = type;
    350 	cur->name = arg;
    351 	arglist = cur;
    352 }
    353 
    354 /*
    355  * addtty --
    356  *	add an entry to a linked list of ttys
    357  */
    358 TTY *
    359 addtty(ttyname)
    360 	char *ttyname;
    361 {
    362 	TTY *cur;
    363 
    364 	if (!(cur = (TTY *)malloc((u_int)sizeof(TTY))))
    365 		err(1, "malloc failure");
    366 	cur->next = ttylist;
    367 	cur->logout = currentout;
    368 	memmove(cur->tty, ttyname, UT_LINESIZE);
    369 	return (ttylist = cur);
    370 }
    371 
    372 /*
    373  * hostconv --
    374  *	convert the hostname to search pattern; if the supplied host name
    375  *	has a domain attached that is the same as the current domain, rip
    376  *	off the domain suffix since that's what login(1) does.
    377  */
    378 void
    379 hostconv(arg)
    380 	char *arg;
    381 {
    382 	static int first = 1;
    383 	static char *hostdot, name[MAXHOSTNAMELEN];
    384 	char *argdot;
    385 
    386 	if (!(argdot = strchr(arg, '.')))
    387 		return;
    388 	if (first) {
    389 		first = 0;
    390 		if (gethostname(name, sizeof(name)))
    391 			err(1, "gethostname");
    392 		hostdot = strchr(name, '.');
    393 	}
    394 	if (hostdot && !strcasecmp(hostdot, argdot))
    395 		*argdot = '\0';
    396 }
    397 
    398 /*
    399  * ttyconv --
    400  *	convert tty to correct name.
    401  */
    402 char *
    403 ttyconv(arg)
    404 	char *arg;
    405 {
    406 	char *mval;
    407 
    408 	/*
    409 	 * kludge -- we assume that all tty's end with
    410 	 * a two character suffix.
    411 	 */
    412 	if (strlen(arg) == 2) {
    413 		/* either 6 for "ttyxx" or 8 for "console" */
    414 		if (!(mval = malloc((u_int)8)))
    415 			err(1, "malloc failure");
    416 		if (!strcmp(arg, "co"))
    417 			(void)strcpy(mval, "console");
    418 		else {
    419 			(void)strcpy(mval, "tty");
    420 			(void)strcpy(mval + 3, arg);
    421 		}
    422 		return (mval);
    423 	}
    424 	if (!strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1))
    425 		return (arg + 5);
    426 	return (arg);
    427 }
    428 
    429 /*
    430  * onintr --
    431  *	on interrupt, we inform the user how far we've gotten
    432  */
    433 void
    434 onintr(signo)
    435 	int signo;
    436 {
    437 	char *ct;
    438 
    439 	ct = ctime(&buf[0].ut_time);
    440 	printf("\ninterrupted %10.10s %8.8s \n", ct, ct + 11);
    441 	if (signo == SIGINT)
    442 		exit(1);
    443 	(void)fflush(stdout);			/* fix required for rsh */
    444 }
    445