lastcomm.c revision 1.31 
1/*	$OpenBSD: lastcomm.c,v 1.31 2022/12/04 23:50:48 cheloha 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/types.h>
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 <unistd.h>
45#include <utmp.h>
46#include <pwd.h>
47#include "pathnames.h"
48
49time_t	 expand(u_int);
50char	*flagbits(int);
51char	*getdev(dev_t);
52int	 requested(char *[], struct acct *);
53void	 usage(void);
54
55#define SECSPERMIN	(60)
56#define SECSPERHOUR	(60 * 60)
57
58int
59main(int argc, char *argv[])
60{
61	char *p;
62	struct acct ab;
63	struct stat sb;
64	FILE *fp;
65	off_t size;
66	time_t t;
67	double delta;
68	int ch;
69	char *acctfile;
70
71	if (pledge("stdio rpath getpw", NULL) == -1)
72		err(1, "pledge");
73
74	acctfile = _PATH_ACCT;
75	while ((ch = getopt(argc, argv, "f:")) != -1)
76		switch(ch) {
77		case 'f':
78			acctfile = optarg;
79			break;
80		default:
81			usage();
82		}
83	argc -= optind;
84	argv += optind;
85
86	/* Open the file. */
87	if ((fp = fopen(acctfile, "r")) == NULL || fstat(fileno(fp), &sb))
88		err(1, "%s", acctfile);
89
90	/*
91	 * Round off to integral number of accounting records, probably
92	 * not necessary, but it doesn't hurt.
93	 */
94	size = sb.st_size - sb.st_size % sizeof(struct acct);
95
96	/* Check if any records to display. */
97	if (size < sizeof(struct acct))
98		exit(0);
99
100	/*
101	 * Seek to before the last entry in the file; use lseek(2) in case
102	 * the file is bigger than a "long".
103	 */
104	size -= sizeof(struct acct);
105	if (lseek(fileno(fp), size, SEEK_SET) == -1)
106		err(1, "%s", acctfile);
107
108	for (;;) {
109		if (fread(&ab, sizeof(struct acct), 1, fp) != 1)
110			err(1, "%s", acctfile);
111
112		if (ab.ac_comm[0] == '\0') {
113			ab.ac_comm[0] = '?';
114			ab.ac_comm[1] = '\0';
115		} else
116			for (p = &ab.ac_comm[0];
117			    p < &ab.ac_comm[sizeof ab.ac_comm] && *p; ++p)
118				if (!isprint((unsigned char)*p))
119					*p = '?';
120		if (!*argv || requested(argv, &ab)) {
121			t = expand(ab.ac_utime) + expand(ab.ac_stime);
122			(void)printf("%-*.*s %-7s %-*.*s %-*.*s %6.2f secs %.16s",
123			    (int)sizeof ab.ac_comm,
124			    (int)sizeof ab.ac_comm,
125			    ab.ac_comm, flagbits(ab.ac_flag), UT_NAMESIZE,
126			    UT_NAMESIZE, user_from_uid(ab.ac_uid, 0),
127			    UT_LINESIZE, UT_LINESIZE, getdev(ab.ac_tty),
128			    t / (double)AHZ, ctime(&ab.ac_btime));
129			delta = expand(ab.ac_etime) / (double)AHZ;
130			printf(" (%1.0f:%02.0f:%05.2f)\n",
131			    delta / SECSPERHOUR,
132			    fmod(delta, (double)SECSPERHOUR) / SECSPERMIN,
133			    fmod(delta, (double)SECSPERMIN));
134		}
135
136		if (size == 0)
137			break;
138		/* seek to previous entry */
139		if (fseek(fp, 2 * -(long)sizeof(struct acct), SEEK_CUR) == -1)
140			err(1, "%s", acctfile);
141		size -= sizeof(struct acct);
142	}
143	exit(0);
144}
145
146time_t
147expand(u_int t)
148{
149	time_t nt;
150
151	nt = t & 017777;
152	t >>= 13;
153	while (t) {
154		t--;
155		nt <<= 3;
156	}
157	return (nt);
158}
159
160char *
161flagbits(int f)
162{
163	static char flags[20] = "-";
164	char *p;
165
166#define	BIT(flag, ch)	if (f & flag) *p++ = ch
167
168	p = flags + 1;
169	BIT(AFORK, 'F');
170	BIT(AMAP, 'M');
171	BIT(ACORE, 'D');
172	BIT(AXSIG, 'X');
173	BIT(APLEDGE, 'P');
174	BIT(ATRAP, 'T');
175	BIT(AUNVEIL, 'U');
176	*p = '\0';
177	return (flags);
178}
179
180int
181requested(char *argv[], struct acct *acp)
182{
183	do {
184		if (!strcmp(user_from_uid(acp->ac_uid, 0), *argv))
185			return (1);
186		if (!strcmp(getdev(acp->ac_tty), *argv))
187			return (1);
188		if (!strncmp(acp->ac_comm, *argv, sizeof acp->ac_comm))
189			return (1);
190	} while (*++argv);
191	return (0);
192}
193
194char *
195getdev(dev_t dev)
196{
197	static dev_t lastdev = (dev_t)-1;
198	static char *lastname;
199
200	if (dev == -1)				/* Special case. */
201		return ("__");
202	if (dev == lastdev)			/* One-element cache. */
203		return (lastname);
204	lastdev = dev;
205	if ((lastname = devname(dev, S_IFCHR)) == NULL)
206		lastname = "??";
207	return (lastname);
208}
209
210void
211usage(void)
212{
213	(void)fprintf(stderr,
214	    "usage: lastcomm [-f file] [command ...] [user ...] [terminal ...]\n");
215	exit(1);
216}
217