lastcomm.c revision 1.14 
1/*	$OpenBSD: lastcomm.c,v 1.14 2004/09/14 22:54:54 deraadt Exp $	*/
2/*	$NetBSD: lastcomm.c,v 1.9 1995/10/22 01:43:42 ghudson Exp $	*/
3
4/*
5 * Copyright (c) 1980, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#ifndef lint
34static char copyright[] =
35"@(#) Copyright (c) 1980, 1993\n\
36	The Regents of the University of California.  All rights reserved.\n";
37#endif /* not lint */
38
39#ifndef lint
40#if 0
41static char sccsid[] = "@(#)lastcomm.c	8.2 (Berkeley) 4/29/95";
42#endif
43static char rcsid[] = "$OpenBSD: lastcomm.c,v 1.14 2004/09/14 22:54:54 deraadt Exp $";
44#endif /* not lint */
45
46#include <sys/param.h>
47#include <sys/stat.h>
48#include <sys/acct.h>
49
50#include <ctype.h>
51#include <err.h>
52#include <fcntl.h>
53#include <math.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <struct.h>
58#include <tzfile.h>
59#include <unistd.h>
60#include <utmp.h>
61#include <pwd.h>
62#include "pathnames.h"
63
64time_t	 expand(u_int);
65char	*flagbits(int);
66char	*getdev(dev_t);
67int	 requested(char *[], struct acct *);
68void	 usage(void);
69
70int
71main(int argc, char *argv[])
72{
73	char *p;
74	struct acct ab;
75	struct stat sb;
76	FILE *fp;
77	off_t size;
78	time_t t;
79	double delta;
80	int ch;
81	char *acctfile;
82
83	acctfile = _PATH_ACCT;
84	while ((ch = getopt(argc, argv, "f:")) != -1)
85		switch((char)ch) {
86		case 'f':
87			acctfile = optarg;
88			break;
89		case '?':
90		default:
91			usage();
92		}
93	argc -= optind;
94	argv += optind;
95
96	/* Open the file. */
97	if ((fp = fopen(acctfile, "r")) == NULL || fstat(fileno(fp), &sb))
98		err(1, "%s", acctfile);
99
100	/*
101	 * Round off to integral number of accounting records, probably
102	 * not necessary, but it doesn't hurt.
103	 */
104	size = sb.st_size - sb.st_size % sizeof(struct acct);
105
106	/* Check if any records to display. */
107	if (size < sizeof(struct acct))
108		exit(0);
109
110	/*
111	 * Seek to before the last entry in the file; use lseek(2) in case
112	 * the file is bigger than a "long".
113	 */
114	size -= sizeof(struct acct);
115	if (lseek(fileno(fp), size, SEEK_SET) == -1)
116		err(1, "%s", acctfile);
117
118	for (;;) {
119		if (fread(&ab, sizeof(struct acct), 1, fp) != 1)
120			err(1, "%s", acctfile);
121
122		if (ab.ac_comm[0] == '\0') {
123			ab.ac_comm[0] = '?';
124			ab.ac_comm[1] = '\0';
125		} else
126			for (p = &ab.ac_comm[0];
127			    p < &ab.ac_comm[fldsiz(acct, ac_comm)] && *p; ++p)
128				if (!isprint(*p))
129					*p = '?';
130		if (!*argv || requested(argv, &ab))
131		{
132			t = expand(ab.ac_utime) + expand(ab.ac_stime);
133			(void)printf("%-*.*s %-7s %-*.*s %-*.*s %6.2f secs %.16s",
134			    (int)fldsiz(acct, ac_comm),
135			    (int)fldsiz(acct, ac_comm),
136			    ab.ac_comm, flagbits(ab.ac_flag), UT_NAMESIZE,
137			    UT_NAMESIZE, user_from_uid(ab.ac_uid, 0),
138			    UT_LINESIZE, UT_LINESIZE, getdev(ab.ac_tty),
139			    t / (double)AHZ, ctime(&ab.ac_btime));
140			delta = expand(ab.ac_etime) / (double)AHZ;
141			printf(" (%1.0f:%02.0f:%05.2f)\n",
142			    delta / SECSPERHOUR,
143			    fmod(delta, (double)SECSPERHOUR) / SECSPERMIN,
144			    fmod(delta, (double)SECSPERMIN));
145		}
146
147		if (size == 0)
148			break;
149		/* seek to previous entry */
150		if (fseek(fp, 2 * -(long)sizeof(struct acct), SEEK_CUR) == -1)
151			err(1, "%s", acctfile);
152		size -= sizeof(struct acct);
153	}
154	exit(0);
155}
156
157time_t
158expand(u_int t)
159{
160	time_t nt;
161
162	nt = t & 017777;
163	t >>= 13;
164	while (t) {
165		t--;
166		nt <<= 3;
167	}
168	return (nt);
169}
170
171char *
172flagbits(int f)
173{
174	static char flags[20] = "-";
175	char *p;
176
177#define	BIT(flag, ch)	if (f & flag) *p++ = ch
178
179	p = flags + 1;
180	BIT(ASU, 'S');
181	BIT(AFORK, 'F');
182	BIT(ACOMPAT, 'C');
183	BIT(ACORE, 'D');
184	BIT(AXSIG, 'X');
185	*p = '\0';
186	return (flags);
187}
188
189int
190requested(char *argv[], struct acct *acp)
191{
192	do {
193		if (!strcmp(user_from_uid(acp->ac_uid, 0), *argv))
194			return (1);
195		if (!strcmp(getdev(acp->ac_tty), *argv))
196			return (1);
197		if (!strncmp(acp->ac_comm, *argv, fldsiz(acct, ac_comm)))
198			return (1);
199	} while (*++argv);
200	return (0);
201}
202
203char *
204getdev(dev_t dev)
205{
206	static dev_t lastdev = (dev_t)-1;
207	static char *lastname;
208
209	if (dev == NODEV)			/* Special case. */
210		return ("__");
211	if (dev == lastdev)			/* One-element cache. */
212		return (lastname);
213	lastdev = dev;
214	if ((lastname = devname(dev, S_IFCHR)) == NULL)
215		lastname = "??";
216	return (lastname);
217}
218
219void
220usage(void)
221{
222	(void)fprintf(stderr,
223	    "lastcomm [ -f file ] [command ...] [user ...] [tty ...]\n");
224	exit(1);
225}
226