lastcomm.c revision 1.23 
1/*	$OpenBSD: lastcomm.c,v 1.23 2015/10/09 01:37:08 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#include <sys/param.h>	/* NODEV */
34#include <sys/stat.h>
35#include <sys/acct.h>
36
37#include <ctype.h>
38#include <err.h>
39#include <fcntl.h>
40#include <math.h>
41#include <stdio.h>
42#include <stdlib.h>
43#include <string.h>
44#include <struct.h>
45#include <unistd.h>
46#include <utmp.h>
47#include <pwd.h>
48#include "pathnames.h"
49
50time_t	 expand(u_int);
51char	*flagbits(int);
52char	*getdev(dev_t);
53int	 requested(char *[], struct acct *);
54void	 usage(void);
55
56#define SECSPERMIN	(60)
57#define SECSPERHOUR	(60 * 60)
58
59int
60main(int argc, char *argv[])
61{
62	char *p;
63	struct acct ab;
64	struct stat sb;
65	FILE *fp;
66	off_t size;
67	time_t t;
68	double delta;
69	int ch;
70	char *acctfile;
71
72	if (pledge("stdio rpath getpw", NULL) == -1)
73		err(1, "pledge");
74
75	acctfile = _PATH_ACCT;
76	while ((ch = getopt(argc, argv, "f:")) != -1)
77		switch(ch) {
78		case 'f':
79			acctfile = optarg;
80			break;
81		case '?':
82		default:
83			usage();
84		}
85	argc -= optind;
86	argv += optind;
87
88	/* Open the file. */
89	if ((fp = fopen(acctfile, "r")) == NULL || fstat(fileno(fp), &sb))
90		err(1, "%s", acctfile);
91
92	/*
93	 * Round off to integral number of accounting records, probably
94	 * not necessary, but it doesn't hurt.
95	 */
96	size = sb.st_size - sb.st_size % sizeof(struct acct);
97
98	/* Check if any records to display. */
99	if (size < sizeof(struct acct))
100		exit(0);
101
102	/*
103	 * Seek to before the last entry in the file; use lseek(2) in case
104	 * the file is bigger than a "long".
105	 */
106	size -= sizeof(struct acct);
107	if (lseek(fileno(fp), size, SEEK_SET) == -1)
108		err(1, "%s", acctfile);
109
110	for (;;) {
111		if (fread(&ab, sizeof(struct acct), 1, fp) != 1)
112			err(1, "%s", acctfile);
113
114		if (ab.ac_comm[0] == '\0') {
115			ab.ac_comm[0] = '?';
116			ab.ac_comm[1] = '\0';
117		} else
118			for (p = &ab.ac_comm[0];
119			    p < &ab.ac_comm[fldsiz(acct, ac_comm)] && *p; ++p)
120				if (!isprint((unsigned char)*p))
121					*p = '?';
122		if (!*argv || requested(argv, &ab))
123		{
124			t = expand(ab.ac_utime) + expand(ab.ac_stime);
125			(void)printf("%-*.*s %-7s %-*.*s %-*.*s %6.2f secs %.16s",
126			    (int)fldsiz(acct, ac_comm),
127			    (int)fldsiz(acct, ac_comm),
128			    ab.ac_comm, flagbits(ab.ac_flag), UT_NAMESIZE,
129			    UT_NAMESIZE, user_from_uid(ab.ac_uid, 0),
130			    UT_LINESIZE, UT_LINESIZE, getdev(ab.ac_tty),
131			    t / (double)AHZ, ctime(&ab.ac_btime));
132			delta = expand(ab.ac_etime) / (double)AHZ;
133			printf(" (%1.0f:%02.0f:%05.2f)\n",
134			    delta / SECSPERHOUR,
135			    fmod(delta, (double)SECSPERHOUR) / SECSPERMIN,
136			    fmod(delta, (double)SECSPERMIN));
137		}
138
139		if (size == 0)
140			break;
141		/* seek to previous entry */
142		if (fseek(fp, 2 * -(long)sizeof(struct acct), SEEK_CUR) == -1)
143			err(1, "%s", acctfile);
144		size -= sizeof(struct acct);
145	}
146	exit(0);
147}
148
149time_t
150expand(u_int t)
151{
152	time_t nt;
153
154	nt = t & 017777;
155	t >>= 13;
156	while (t) {
157		t--;
158		nt <<= 3;
159	}
160	return (nt);
161}
162
163char *
164flagbits(int f)
165{
166	static char flags[20] = "-";
167	char *p;
168
169#define	BIT(flag, ch)	if (f & flag) *p++ = ch
170
171	p = flags + 1;
172	BIT(ASU, 'S');
173	BIT(AFORK, 'F');
174	BIT(ACOMPAT, 'C');
175	BIT(ACORE, 'D');
176	BIT(AXSIG, 'X');
177	*p = '\0';
178	return (flags);
179}
180
181int
182requested(char *argv[], struct acct *acp)
183{
184	do {
185		if (!strcmp(user_from_uid(acp->ac_uid, 0), *argv))
186			return (1);
187		if (!strcmp(getdev(acp->ac_tty), *argv))
188			return (1);
189		if (!strncmp(acp->ac_comm, *argv, fldsiz(acct, ac_comm)))
190			return (1);
191	} while (*++argv);
192	return (0);
193}
194
195char *
196getdev(dev_t dev)
197{
198	static dev_t lastdev = (dev_t)-1;
199	static char *lastname;
200
201	if (dev == NODEV)			/* Special case. */
202		return ("__");
203	if (dev == lastdev)			/* One-element cache. */
204		return (lastname);
205	lastdev = dev;
206	if ((lastname = devname(dev, S_IFCHR)) == NULL)
207		lastname = "??";
208	return (lastname);
209}
210
211void
212usage(void)
213{
214	(void)fprintf(stderr,
215	    "usage: lastcomm [-f file] [command ...] [user ...] [terminal ...]\n");
216	exit(1);
217}
218