1/*
2 * Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
3 *
4 * Copyright (c) 1987, 1993, 1994
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * The NEXTSTEP Software License Agreement specifies the terms
8 * and conditions for redistribution.
9 *
10 *	@(#)last.c	8.2 (Berkeley) 4/2/94
11 */
12
13
14#ifndef lint
15static const char copyright[] =
16"@(#) Copyright (c) 1987, 1993, 1994\n\
17	The Regents of the University of California.  All rights reserved.\n";
18#endif /* not lint */
19
20#include <sys/param.h>
21#include <sys/stat.h>
22
23#include <err.h>
24#include <fcntl.h>
25#include <paths.h>
26#include <signal.h>
27#include <stdio.h>
28#include <stdlib.h>
29#include <string.h>
30#include <time.h>
31#include <tzfile.h>
32#include <unistd.h>
33#include <utmpx.h>
34#include <ctype.h>
35
36#define	NO	0				/* false/no */
37#define	YES	1				/* true/yes */
38
39static const struct utmpx	*prev;		/* previous utmpx structure */
40
41/* values from utmp.h, used for print formatting */
42#define	UT_NAMESIZE	8			/* old utmp.h value */
43#define	UT_LINESIZE	8
44#define	UT_HOSTSIZE	16
45
46typedef struct arg {
47	const char	*name;			/* argument */
48#define	HOST_TYPE	-2
49#define	TTY_TYPE	-3
50#define	USER_TYPE	-4
51	int	type;				/* type of arg */
52	struct arg	*next;			/* linked list pointer */
53} ARG;
54ARG	*arglist;				/* head of linked list */
55
56typedef struct ttytab {
57	long	logout;				/* log out time */
58	char	id[_UTX_IDSIZE];		/* terminal id */
59	pid_t	pid;
60	struct ttytab	*next;			/* linked list pointer */
61} TTY;
62TTY	*ttylist;				/* head of linked list */
63
64static const	char *crmsg;			/* cause of last reboot */
65static long	currentout,			/* current logout value */
66		maxrec;				/* records to display */
67time_t	now;
68
69void	 addarg __P((int, const char *));
70TTY	*addtty __P((const char *, pid_t));
71void	 hostconv __P((const char *));
72void	 onintr __P((int));
73const char	*ttyconv __P((const char *));
74int	 want __P((struct utmpx *, int));
75void	 wtmp __P((void));
76
77int
78main(argc, argv)
79	int argc;
80	char *argv[];
81{
82	extern int optind;
83	extern char *optarg;
84	int ch;
85	char *p;
86	char *myname = *argv;
87
88	if ((p = strrchr(myname, '/')) != NULL)
89		myname = p + 1;
90	maxrec = -1;
91	while ((ch = getopt(argc, argv, "0123456789f:h:t:")) != EOF)
92		switch (ch) {
93		case '0': case '1': case '2': case '3': case '4':
94		case '5': case '6': case '7': case '8': case '9':
95			/*
96			 * kludge: last was originally designed to take
97			 * a number after a dash.
98			 */
99			if (maxrec == -1) {
100				p = argv[optind - 1];
101				if (p[0] == '-' && p[1] == ch && !p[2])
102					maxrec = atol(++p);
103				else
104					maxrec = atol(argv[optind] + 1);
105				if (!maxrec)
106					exit(0);
107			}
108			break;
109		case 'h':
110			hostconv(optarg);
111			addarg(HOST_TYPE, optarg);
112			break;
113		case 't':
114			addarg(TTY_TYPE, ttyconv(optarg));
115			break;
116		case 'f':
117			warnx("-f is unsupported");
118			break;
119		case '?':
120		default:
121			(void)fprintf(stderr,
122	"usage: last [-#] [-t tty] [-h hostname] [user ...]\n");
123			exit(1);
124		}
125
126	if (argc) {
127		setlinebuf(stdout);
128		for (argv += optind; *argv; ++argv) {
129#define	COMPATIBILITY
130#ifdef	COMPATIBILITY
131			/* code to allow "last p5" to work */
132			addarg(TTY_TYPE, ttyconv(*argv));
133#endif
134			addarg(USER_TYPE, *argv);
135		}
136	}
137	wtmp();
138	exit(0);
139}
140
141/*
142 * wtmp --
143 *	read through the wtmp file
144 */
145
146void
147wtmp()
148{
149
150	struct utmpx	*bp;			/* current structure */
151	TTY	*T;				/* tty list entry */
152	long	delta;				/* time difference */
153	char	*ct;
154
155	(void)time(&now);
156	(void)signal(SIGINT, onintr);
157	(void)signal(SIGQUIT, onintr);
158
159	setutxent_wtmp(0);	/* zero means reverse chronological order */
160	while ((bp = getutxent_wtmp()) != NULL) {
161		prev = bp;
162		switch(bp->ut_type) {
163		case BOOT_TIME:
164		case SHUTDOWN_TIME:
165			/* everybody just logged out */
166			for (T = ttylist; T; T = T->next)
167				T->logout = -bp->ut_tv.tv_sec;
168			currentout = -bp->ut_tv.tv_sec;
169			crmsg = bp->ut_type == BOOT_TIME ? "crash" : "shutdown";
170			if (want(bp, NO)) {
171				ct = ctime(&bp->ut_tv.tv_sec);
172				printf("%-*s  %-*s %-*.*s %10.10s %5.5s \n",
173				    UT_NAMESIZE, bp->ut_type == BOOT_TIME ? "reboot" : "shutdown",
174				    UT_LINESIZE, "~",
175				    UT_HOSTSIZE, _UTX_HOSTSIZE,
176				    bp->ut_host, ct, ct + 11);
177				if (maxrec != -1 && !--maxrec)
178					return;
179			}
180			continue;
181		case OLD_TIME:
182		case NEW_TIME:
183			if (want(bp, NO)) {
184				ct = ctime(&bp->ut_tv.tv_sec);
185				printf("%-*s  %-*s %-*.*s %10.10s %5.5s \n",
186				    UT_NAMESIZE, "date",
187				    UT_LINESIZE, bp->ut_type == OLD_TIME ? "|" : "{",
188				    UT_HOSTSIZE, _UTX_HOSTSIZE, bp->ut_host,
189				    ct, ct + 11);
190				if (maxrec && !--maxrec)
191					return;
192			}
193			continue;
194		case USER_PROCESS:
195		case DEAD_PROCESS:
196			/* find associated tty */
197			for (T = ttylist;; T = T->next) {
198				if (!T) {
199					/* add new one */
200					T = addtty(bp->ut_id, bp->ut_pid);
201					break;
202				}
203				if (!memcmp(T->id, bp->ut_id, _UTX_IDSIZE) && T->pid == bp->ut_pid)
204					break;
205			}
206			if (bp->ut_type != DEAD_PROCESS && want(bp, YES)) {
207				ct = ctime(&bp->ut_tv.tv_sec);
208				printf("%-*.*s  %-*.*s %-*.*s %10.10s %5.5s ",
209				UT_NAMESIZE, _UTX_USERSIZE, bp->ut_user,
210				UT_LINESIZE, _UTX_LINESIZE, bp->ut_line,
211				UT_HOSTSIZE, _UTX_HOSTSIZE, bp->ut_host,
212				ct, ct + 11);
213				if (!T->logout)
214					puts("  still logged in");
215				else {
216					if (T->logout < 0) {
217						T->logout = -T->logout;
218						printf("- %s", crmsg);
219					}
220					else
221						printf("- %5.5s",
222						    ctime(&T->logout)+11);
223					delta = T->logout - bp->ut_tv.tv_sec;
224					if (delta < SECSPERDAY)
225						printf("  (%5.5s)\n",
226						    asctime(gmtime(&delta))+11);
227					else
228						printf(" (%ld+%5.5s)\n",
229						    delta / SECSPERDAY,
230						    asctime(gmtime(&delta))+11);
231				}
232				if (maxrec != -1 && !--maxrec)
233					return;
234			}
235			T->logout = bp->ut_tv.tv_sec;
236			continue;
237		}
238	}
239	endutxent_wtmp();
240	ct = ctime(prev ? &prev->ut_tv.tv_sec : &now);
241	printf("\nwtmp begins %10.10s %5.5s \n", ct, ct + 11);
242}
243
244/*
245 * want --
246 *	see if want this entry
247 */
248int
249want(bp, check)
250	struct utmpx *bp;
251	int check;
252{
253	ARG *step;
254
255	if (!arglist)
256		return (YES);
257
258	for (step = arglist; step; step = step->next)
259		switch(step->type) {
260		case HOST_TYPE:
261			if (!strncasecmp(step->name, bp->ut_host, _UTX_HOSTSIZE))
262				return (YES);
263			break;
264		case TTY_TYPE:
265		{
266			char *line = bp->ut_line;
267			if (check) {
268				/*
269				 * when uucp and ftp log in over a network, the entry in
270				 * the utmpx file is the name plus their process id.  See
271				 * etc/ftpd.c and usr.bin/uucp/uucpd.c for more information.
272				 */
273				if (!strncmp(line, "ftp", sizeof("ftp") - 1))
274					line = "ftp";
275				else if (!strncmp(line, "uucp", sizeof("uucp") - 1))
276					line = "uucp";
277			}
278			if (!strncmp(step->name, line, _UTX_LINESIZE))
279				return (YES);
280			break;
281		}
282		case USER_TYPE:
283			if (bp->ut_type == BOOT_TIME && !strncmp(step->name, "reboot", _UTX_USERSIZE))
284				return (YES);
285			if (bp->ut_type == SHUTDOWN_TIME && !strncmp(step->name, "shutdown", _UTX_USERSIZE))
286				return (YES);
287			if (!strncmp(step->name, bp->ut_user, _UTX_USERSIZE))
288				return (YES);
289			break;
290	}
291	return (NO);
292}
293
294/*
295 * addarg --
296 *	add an entry to a linked list of arguments
297 */
298void
299addarg(type, arg)
300	int type;
301	const char *arg;
302{
303	ARG *cur;
304
305	if (!(cur = (ARG *)malloc((u_int)sizeof(ARG))))
306		err(1, "malloc failure");
307	cur->next = arglist;
308	cur->type = type;
309	cur->name = arg;
310	arglist = cur;
311}
312
313/*
314 * addtty --
315 *	add an entry to a linked list of ttys
316 */
317TTY *
318addtty(id, pid)
319	const char *id;
320	pid_t pid;
321{
322	TTY *cur;
323
324	if (!(cur = (TTY *)malloc((u_int)sizeof(TTY))))
325		err(1, "malloc failure");
326	cur->next = ttylist;
327	cur->logout = currentout;
328	memmove(cur->id, id, _UTX_IDSIZE);
329	cur->pid = pid;
330	return (ttylist = cur);
331}
332
333/*
334 * hostconv --
335 *	convert the hostname to search pattern; if the supplied host name
336 *	has a domain attached that is the same as the current domain, rip
337 *	off the domain suffix since that's what login(1) does.
338 */
339void
340hostconv(arg)
341	const char *arg;
342{
343	static int first = 1;
344	static char *hostdot, name[MAXHOSTNAMELEN];
345	char *argdot;
346
347	if (!(argdot = strchr(arg, '.')))
348		return;
349	if (first) {
350		first = 0;
351		if (gethostname(name, sizeof(name)))
352			err(1, "gethostname");
353		hostdot = strchr(name, '.');
354	}
355	if (hostdot && !strcasecmp(hostdot, argdot))
356		*argdot = '\0';
357}
358
359/*
360 * ttyconv --
361 *	convert tty to correct name.
362 */
363const char *
364ttyconv(arg)
365	const char *arg;
366{
367	char *mval;
368	int kludge = 0;
369	int len = strlen(arg);
370
371	/*
372	 * kludge -- we assume that most tty's end with
373	 * a two character suffix.
374	 */
375	if (len == 2)
376		kludge = 8; /* either 6 for "ttyxx" or 8 for "console"; use largest */
377	/*
378	 * kludge -- we assume cloning ptys names are "ttys" followed by
379	 * more than one digit
380	 */
381	else if (len > 2 && *arg == 's') {
382		const char *cp = arg + 1;
383		while(*cp && isdigit(*cp))
384			cp++;
385		if (*cp == 0)
386			kludge = len + sizeof("tty");
387	}
388	if (kludge) {
389		if (!(mval = malloc(kludge)))
390			err(1, "malloc failure");
391		if (!strcmp(arg, "co"))
392			(void)strcpy(mval, "console");
393		else {
394			(void)strcpy(mval, "tty");
395			(void)strcpy(mval + sizeof("tty") - 1, arg);
396		}
397		return (mval);
398	}
399	if (!strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1))
400		return (arg + sizeof(_PATH_DEV) - 1);
401	return (arg);
402}
403
404/*
405 * onintr --
406 *	on interrupt, we inform the user how far we've gotten
407 */
408void
409onintr(signo)
410	int signo;
411{
412	char *ct;
413
414	ct = ctime(prev ? &prev->ut_tv.tv_sec : &now);
415	printf("\ninterrupted %10.10s %5.5s \n", ct, ct + 11);
416	if (signo == SIGINT)
417		exit(1);
418	(void)fflush(stdout);			/* fix required for rsh */
419}
420