1/*	$NetBSD: lastcomm.c,v 1.21 2009/04/12 13:08:31 lukem Exp $	*/
2
3/*
4 * Copyright (c) 1980, 1993
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#include <sys/cdefs.h>
33#ifndef lint
34__COPYRIGHT("@(#) Copyright (c) 1980, 1993\
35 The Regents of the University of California.  All rights reserved.");
36#endif /* not lint */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)lastcomm.c	8.2 (Berkeley) 4/29/95";
41#endif
42__RCSID("$NetBSD: lastcomm.c,v 1.21 2009/04/12 13:08:31 lukem Exp $");
43#endif /* not lint */
44
45#include <sys/param.h>
46#include <sys/stat.h>
47#include <sys/acct.h>
48
49#include <ctype.h>
50#include <err.h>
51#include <fcntl.h>
52#include <math.h>
53#include <pwd.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <struct.h>
58#include <time.h>
59#include <tzfile.h>
60#include <unistd.h>
61/* definitions from utmp.h */
62#define UT_NAMESIZE     8
63#define UT_LINESIZE     8
64#include "pathnames.h"
65
66static time_t	 	 expand(u_int);
67static char		*flagbits(int);
68static const char	*getdev(dev_t);
69static int	 	 requested(char *[], struct acct *);
70static void	 	 usage(void) __dead;
71
72int	main(int, char **);
73
74int
75main(int argc, char *argv[])
76{
77	char *p;
78	struct acct ab;
79	struct stat sb;
80	FILE *fp;
81	off_t size;
82	time_t t;
83	double delta;
84	int ch;
85	const char *acctfile = _PATH_ACCT;
86
87	setprogname(argv[0]);
88
89	while ((ch = getopt(argc, argv, "f:")) != -1)
90		switch((char)ch) {
91		case 'f':
92			acctfile = optarg;
93			break;
94		case '?':
95		default:
96			usage();
97		}
98	argc -= optind;
99	argv += optind;
100
101	/* Open the file. */
102	if ((fp = fopen(acctfile, "r")) == NULL || fstat(fileno(fp), &sb))
103		err(1, "%s", acctfile);
104
105	/*
106	 * Round off to integral number of accounting records, probably
107	 * not necessary, but it doesn't hurt.
108	 */
109	size = sb.st_size - sb.st_size % sizeof(struct acct);
110
111	/* Check if any records to display. */
112	if (size < (off_t)sizeof(struct acct))
113		exit(0);
114
115	/*
116	 * Seek to before the last entry in the file; use lseek(2) in case
117	 * the file is bigger than a "long".
118	 */
119	size -= sizeof(struct acct);
120	if (lseek(fileno(fp), size, SEEK_SET) == -1)
121		err(1, "%s", acctfile);
122
123	for (;;) {
124		if (fread(&ab, sizeof(struct acct), 1, fp) != 1)
125			err(1, "%s", acctfile);
126
127		if (ab.ac_comm[0] == '\0') {
128			ab.ac_comm[0] = '?';
129			ab.ac_comm[1] = '\0';
130		} else
131			for (p = &ab.ac_comm[0];
132			    p < &ab.ac_comm[fldsiz(acct, ac_comm)] && *p; ++p)
133				if (!isprint((unsigned char)*p))
134					*p = '?';
135		if (!*argv || requested(argv, &ab)) {
136
137			t = expand(ab.ac_utime) + expand(ab.ac_stime);
138			(void)printf(
139			    "%-*.*s %-7s %-*.*s %-*.*s %6.2f secs %.16s",
140			     (int)fldsiz(acct, ac_comm),
141			     (int)fldsiz(acct, ac_comm),
142			     ab.ac_comm, flagbits(ab.ac_flag),
143			     UT_NAMESIZE, UT_NAMESIZE,
144			     user_from_uid(ab.ac_uid, 0), UT_LINESIZE,
145			     UT_LINESIZE, getdev(ab.ac_tty),
146			     t / (double)AHZ, ctime(&ab.ac_btime));
147			delta = expand(ab.ac_etime) / (double)AHZ;
148			printf(" (%1.0f:%02.0f:%05.2f)\n",
149			       floor(delta / SECSPERHOUR),
150			       floor(fmod(delta, SECSPERHOUR) / SECSPERMIN),
151			       fmod(delta, SECSPERMIN));
152		}
153		/* are we at the beginning of the file yet? */
154		if (size == 0)
155			break;
156		/* seek backward over the one we read and the next to read */
157		if (fseek(fp, 2 * -(long)sizeof(struct acct), SEEK_CUR) == -1)
158			err(1, "%s", acctfile);
159		/* and account for its size */
160		size -= sizeof(struct acct);
161	}
162	exit(0);
163}
164
165static time_t
166expand(u_int t)
167{
168	time_t nt;
169
170	nt = t & 017777;
171	t >>= 13;
172	while (t) {
173		t--;
174		nt <<= 3;
175	}
176	return (nt);
177}
178
179static char *
180flagbits(int f)
181{
182	static char flags[20] = "-";
183	char *p;
184
185#define	BIT(flag, ch)	if (f & flag) *p++ = ch
186
187	p = flags + 1;
188	BIT(ASU, 'S');
189	BIT(AFORK, 'F');
190	BIT(ACOMPAT, 'C');
191	BIT(ACORE, 'D');
192	BIT(AXSIG, 'X');
193	*p = '\0';
194	return (flags);
195}
196
197static int
198requested(char *argv[], struct acct *acp)
199{
200	do {
201		if (!strcmp(user_from_uid(acp->ac_uid, 0), *argv))
202			return (1);
203		if (!strcmp(getdev(acp->ac_tty), *argv))
204			return (1);
205		if (!strncmp(acp->ac_comm, *argv, fldsiz(acct, ac_comm)))
206			return (1);
207	} while (*++argv);
208	return (0);
209}
210
211static const char *
212getdev(dev_t dev)
213{
214	static dev_t lastdev = (dev_t)-1;
215	static const char *lastname;
216
217	if (dev == NODEV)			/* Special case. */
218		return ("__");
219	if (dev == lastdev)			/* One-element cache. */
220		return (lastname);
221	lastdev = dev;
222	if ((lastname = devname(dev, S_IFCHR)) == NULL)
223		lastname = "??";
224	return (lastname);
225}
226
227static void
228usage(void)
229{
230	(void)fprintf(stderr,
231	    "Usage: %s [ -f file ] [command ...] [user ...] [tty ...]\n",
232	    getprogname());
233	exit(1);
234}
235