1 /*
2 * Copyright (c) 1987, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * %sccs.include.redist.c%
6 */
7
8 #ifndef lint
9 static char copyright[] =
10 "@(#) Copyright (c) 1987, 1993, 1994\n\
11 The Regents of the University of California. All rights reserved.\n";
12 #endif /* not lint */
13
14 #ifndef lint
15 static char sccsid[] = "@(#)last.c 8.2 (Berkeley) 04/02/94";
16 #endif /* not lint */
17
18 #include <sys/param.h>
19 #include <sys/stat.h>
20
21 #include <err.h>
22 #include <fcntl.h>
23 #include <paths.h>
24 #include <signal.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <time.h>
29 #include <tzfile.h>
30 #include <unistd.h>
31 #include <utmp.h>
32
33 #define NO 0 /* false/no */
34 #define YES 1 /* true/yes */
35
36 static struct utmp buf[1024]; /* utmp read buffer */
37
38 typedef struct arg {
39 char *name; /* argument */
40 #define HOST_TYPE -2
41 #define TTY_TYPE -3
42 #define USER_TYPE -4
43 int type; /* type of arg */
44 struct arg *next; /* linked list pointer */
45 } ARG;
46 ARG *arglist; /* head of linked list */
47
48 typedef struct ttytab {
49 long logout; /* log out time */
50 char tty[UT_LINESIZE + 1]; /* terminal name */
51 struct ttytab *next; /* linked list pointer */
52 } TTY;
53 TTY *ttylist; /* head of linked list */
54
55 static long currentout, /* current logout value */
56 maxrec; /* records to display */
57 static char *file = _PATH_WTMP; /* wtmp file */
58
59 void addarg __P((int, char *));
60 TTY *addtty __P((char *));
61 void hostconv __P((char *));
62 void onintr __P((int));
63 char *ttyconv __P((char *));
64 int want __P((struct utmp *, int));
65 void wtmp __P((void));
66
67 int
main(argc,argv)68 main(argc, argv)
69 int argc;
70 char *argv[];
71 {
72 extern int optind;
73 extern char *optarg;
74 int ch;
75 char *p;
76
77 maxrec = -1;
78 while ((ch = getopt(argc, argv, "0123456789f:h:t:")) != EOF)
79 switch (ch) {
80 case '0': case '1': case '2': case '3': case '4':
81 case '5': case '6': case '7': case '8': case '9':
82 /*
83 * kludge: last was originally designed to take
84 * a number after a dash.
85 */
86 if (maxrec == -1) {
87 p = argv[optind - 1];
88 if (p[0] == '-' && p[1] == ch && !p[2])
89 maxrec = atol(++p);
90 else
91 maxrec = atol(argv[optind] + 1);
92 if (!maxrec)
93 exit(0);
94 }
95 break;
96 case 'f':
97 file = optarg;
98 break;
99 case 'h':
100 hostconv(optarg);
101 addarg(HOST_TYPE, optarg);
102 break;
103 case 't':
104 addarg(TTY_TYPE, ttyconv(optarg));
105 break;
106 case '?':
107 default:
108 (void)fprintf(stderr,
109 "usage: last [-#] [-f file] [-t tty] [-h hostname] [user ...]\n");
110 exit(1);
111 }
112
113 if (argc) {
114 setlinebuf(stdout);
115 for (argv += optind; *argv; ++argv) {
116 #define COMPATIBILITY
117 #ifdef COMPATIBILITY
118 /* code to allow "last p5" to work */
119 addarg(TTY_TYPE, ttyconv(*argv));
120 #endif
121 addarg(USER_TYPE, *argv);
122 }
123 }
124 wtmp();
125 exit(0);
126 }
127
128 /*
129 * wtmp --
130 * read through the wtmp file
131 */
132 void
wtmp()133 wtmp()
134 {
135 struct utmp *bp; /* current structure */
136 TTY *T; /* tty list entry */
137 struct stat stb; /* stat of file for size */
138 long bl, delta; /* time difference */
139 int bytes, wfd;
140 char *ct, *crmsg;
141
142 if ((wfd = open(file, O_RDONLY, 0)) < 0 || fstat(wfd, &stb) == -1)
143 err(1, "%s", file);
144 bl = (stb.st_size + sizeof(buf) - 1) / sizeof(buf);
145
146 (void)time(&buf[0].ut_time);
147 (void)signal(SIGINT, onintr);
148 (void)signal(SIGQUIT, onintr);
149
150 while (--bl >= 0) {
151 if (lseek(wfd, (off_t)(bl * sizeof(buf)), L_SET) == -1 ||
152 (bytes = read(wfd, buf, sizeof(buf))) == -1)
153 err(1, "%s", file);
154 for (bp = &buf[bytes / sizeof(buf[0]) - 1]; bp >= buf; --bp) {
155 /*
156 * if the terminal line is '~', the machine stopped.
157 * see utmp(5) for more info.
158 */
159 if (bp->ut_line[0] == '~' && !bp->ut_line[1]) {
160 /* everybody just logged out */
161 for (T = ttylist; T; T = T->next)
162 T->logout = -bp->ut_time;
163 currentout = -bp->ut_time;
164 crmsg = strncmp(bp->ut_name, "shutdown",
165 UT_NAMESIZE) ? "crash" : "shutdown";
166 if (want(bp, NO)) {
167 ct = ctime(&bp->ut_time);
168 printf("%-*.*s %-*.*s %-*.*s %10.10s %5.5s \n",
169 UT_NAMESIZE, UT_NAMESIZE,
170 bp->ut_name, UT_LINESIZE,
171 UT_LINESIZE, bp->ut_line,
172 UT_HOSTSIZE, UT_HOSTSIZE,
173 bp->ut_host, ct, ct + 11);
174 if (maxrec != -1 && !--maxrec)
175 return;
176 }
177 continue;
178 }
179 /*
180 * if the line is '{' or '|', date got set; see
181 * utmp(5) for more info.
182 */
183 if ((bp->ut_line[0] == '{' || bp->ut_line[0] == '|')
184 && !bp->ut_line[1]) {
185 if (want(bp, NO)) {
186 ct = ctime(&bp->ut_time);
187 printf("%-*.*s %-*.*s %-*.*s %10.10s %5.5s \n",
188 UT_NAMESIZE, UT_NAMESIZE, bp->ut_name,
189 UT_LINESIZE, UT_LINESIZE, bp->ut_line,
190 UT_HOSTSIZE, UT_HOSTSIZE, bp->ut_host,
191 ct, ct + 11);
192 if (maxrec && !--maxrec)
193 return;
194 }
195 continue;
196 }
197 /* find associated tty */
198 for (T = ttylist;; T = T->next) {
199 if (!T) {
200 /* add new one */
201 T = addtty(bp->ut_line);
202 break;
203 }
204 if (!strncmp(T->tty, bp->ut_line, UT_LINESIZE))
205 break;
206 }
207 if (bp->ut_name[0] && want(bp, YES)) {
208 ct = ctime(&bp->ut_time);
209 printf("%-*.*s %-*.*s %-*.*s %10.10s %5.5s ",
210 UT_NAMESIZE, UT_NAMESIZE, bp->ut_name,
211 UT_LINESIZE, UT_LINESIZE, bp->ut_line,
212 UT_HOSTSIZE, UT_HOSTSIZE, bp->ut_host,
213 ct, ct + 11);
214 if (!T->logout)
215 puts(" still logged in");
216 else {
217 if (T->logout < 0) {
218 T->logout = -T->logout;
219 printf("- %s", crmsg);
220 }
221 else
222 printf("- %5.5s",
223 ctime(&T->logout)+11);
224 delta = T->logout - bp->ut_time;
225 if (delta < SECSPERDAY)
226 printf(" (%5.5s)\n",
227 asctime(gmtime(&delta))+11);
228 else
229 printf(" (%ld+%5.5s)\n",
230 delta / SECSPERDAY,
231 asctime(gmtime(&delta))+11);
232 }
233 if (maxrec != -1 && !--maxrec)
234 return;
235 }
236 T->logout = bp->ut_time;
237 }
238 }
239 ct = ctime(&buf[0].ut_time);
240 printf("\nwtmp begins %10.10s %5.5s \n", ct, ct + 11);
241 }
242
243 /*
244 * want --
245 * see if want this entry
246 */
247 int
want(bp,check)248 want(bp, check)
249 struct utmp *bp;
250 int check;
251 {
252 ARG *step;
253
254 if (check)
255 /*
256 * when uucp and ftp log in over a network, the entry in
257 * the utmp file is the name plus their process id. See
258 * etc/ftpd.c and usr.bin/uucp/uucpd.c for more information.
259 */
260 if (!strncmp(bp->ut_line, "ftp", sizeof("ftp") - 1))
261 bp->ut_line[3] = '\0';
262 else if (!strncmp(bp->ut_line, "uucp", sizeof("uucp") - 1))
263 bp->ut_line[4] = '\0';
264 if (!arglist)
265 return (YES);
266
267 for (step = arglist; step; step = step->next)
268 switch(step->type) {
269 case HOST_TYPE:
270 if (!strncasecmp(step->name, bp->ut_host, UT_HOSTSIZE))
271 return (YES);
272 break;
273 case TTY_TYPE:
274 if (!strncmp(step->name, bp->ut_line, UT_LINESIZE))
275 return (YES);
276 break;
277 case USER_TYPE:
278 if (!strncmp(step->name, bp->ut_name, UT_NAMESIZE))
279 return (YES);
280 break;
281 }
282 return (NO);
283 }
284
285 /*
286 * addarg --
287 * add an entry to a linked list of arguments
288 */
289 void
addarg(type,arg)290 addarg(type, arg)
291 int type;
292 char *arg;
293 {
294 ARG *cur;
295
296 if (!(cur = (ARG *)malloc((u_int)sizeof(ARG))))
297 err(1, "malloc failure");
298 cur->next = arglist;
299 cur->type = type;
300 cur->name = arg;
301 arglist = cur;
302 }
303
304 /*
305 * addtty --
306 * add an entry to a linked list of ttys
307 */
308 TTY *
addtty(ttyname)309 addtty(ttyname)
310 char *ttyname;
311 {
312 TTY *cur;
313
314 if (!(cur = (TTY *)malloc((u_int)sizeof(TTY))))
315 err(1, "malloc failure");
316 cur->next = ttylist;
317 cur->logout = currentout;
318 memmove(cur->tty, ttyname, UT_LINESIZE);
319 return (ttylist = cur);
320 }
321
322 /*
323 * hostconv --
324 * convert the hostname to search pattern; if the supplied host name
325 * has a domain attached that is the same as the current domain, rip
326 * off the domain suffix since that's what login(1) does.
327 */
328 void
hostconv(arg)329 hostconv(arg)
330 char *arg;
331 {
332 static int first = 1;
333 static char *hostdot, name[MAXHOSTNAMELEN];
334 char *argdot;
335
336 if (!(argdot = strchr(arg, '.')))
337 return;
338 if (first) {
339 first = 0;
340 if (gethostname(name, sizeof(name)))
341 err(1, "gethostname");
342 hostdot = strchr(name, '.');
343 }
344 if (hostdot && !strcasecmp(hostdot, argdot))
345 *argdot = '\0';
346 }
347
348 /*
349 * ttyconv --
350 * convert tty to correct name.
351 */
352 char *
ttyconv(arg)353 ttyconv(arg)
354 char *arg;
355 {
356 char *mval;
357
358 /*
359 * kludge -- we assume that all tty's end with
360 * a two character suffix.
361 */
362 if (strlen(arg) == 2) {
363 /* either 6 for "ttyxx" or 8 for "console" */
364 if (!(mval = malloc((u_int)8)))
365 err(1, "malloc failure");
366 if (!strcmp(arg, "co"))
367 (void)strcpy(mval, "console");
368 else {
369 (void)strcpy(mval, "tty");
370 (void)strcpy(mval + 3, arg);
371 }
372 return (mval);
373 }
374 if (!strncmp(arg, _PATH_DEV, sizeof(_PATH_DEV) - 1))
375 return (arg + 5);
376 return (arg);
377 }
378
379 /*
380 * onintr --
381 * on interrupt, we inform the user how far we've gotten
382 */
383 void
onintr(signo)384 onintr(signo)
385 int signo;
386 {
387 char *ct;
388
389 ct = ctime(&buf[0].ut_time);
390 printf("\ninterrupted %10.10s %5.5s \n", ct, ct + 11);
391 if (signo == SIGINT)
392 exit(1);
393 (void)fflush(stdout); /* fix required for rsh */
394 }
395