1/*	$OpenBSD: lastcomm.c,v 1.36 2024/02/25 00:07:13 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/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		char commpid[sizeof(ab.ac_comm) + 13];
110
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[sizeof ab.ac_comm] && *p; ++p)
120				if (!isprint((unsigned char)*p))
121					*p = '?';
122		snprintf(commpid, sizeof(commpid), "%s[%d]",
123		    ab.ac_comm, ab.ac_pid);
124		if (!*argv || requested(argv, &ab)) {
125			t = expand(ab.ac_utime) + expand(ab.ac_stime);
126			(void)printf("%-*.*s %-7s %-*.*s %-*.*s %6.2f secs %.16s",
127			    (int)sizeof commpid,
128			    (int)sizeof commpid,
129			    commpid, flagbits(ab.ac_flag), UT_NAMESIZE,
130			    UT_NAMESIZE, user_from_uid(ab.ac_uid, 0),
131			    UT_LINESIZE, UT_LINESIZE, getdev(ab.ac_tty),
132			    t / (double)AHZ, ctime(&ab.ac_btime));
133			delta = expand(ab.ac_etime) / (double)AHZ;
134			printf(" (%1.0f:%02.0f:%05.2f)\n",
135			    delta / SECSPERHOUR,
136			    fmod(delta, (double)SECSPERHOUR) / SECSPERMIN,
137			    fmod(delta, (double)SECSPERMIN));
138		}
139
140		if (size == 0)
141			break;
142		/* seek to previous entry */
143		if (fseek(fp, 2 * -(long)sizeof(struct acct), SEEK_CUR) == -1)
144			err(1, "%s", acctfile);
145		size -= sizeof(struct acct);
146	}
147	exit(0);
148}
149
150time_t
151expand(u_int t)
152{
153	time_t nt;
154
155	nt = t & 017777;
156	t >>= 13;
157	while (t) {
158		t--;
159		nt <<= 3;
160	}
161	return (nt);
162}
163
164char *
165flagbits(int f)
166{
167	static char flags[20] = "-";
168	char *p;
169
170#define	BIT(flag, ch)	if (f & flag) *p++ = ch
171
172	p = flags + 1;
173	BIT(AFORK, 'F');
174	BIT(AMAP, 'M');
175	BIT(ACORE, 'D');
176	BIT(AXSIG, 'X');
177	BIT(APLEDGE, 'P');
178	BIT(ATRAP, 'T');
179	BIT(AUNVEIL, 'U');
180	BIT(APINSYS, 'S');
181	BIT(ABTCFI, 'B');
182	*p = '\0';
183	return (flags);
184}
185
186int
187requested(char *argv[], struct acct *acp)
188{
189	do {
190		if (!strcmp(user_from_uid(acp->ac_uid, 0), *argv))
191			return (1);
192		if (!strcmp(getdev(acp->ac_tty), *argv))
193			return (1);
194		if (!strncmp(acp->ac_comm, *argv, sizeof acp->ac_comm))
195			return (1);
196	} while (*++argv);
197	return (0);
198}
199
200char *
201getdev(dev_t dev)
202{
203	static dev_t lastdev = (dev_t)-1;
204	static char *lastname;
205
206	if (dev == -1)				/* Special case. */
207		return ("__");
208	if (dev == lastdev)			/* One-element cache. */
209		return (lastname);
210	lastdev = dev;
211	if ((lastname = devname(dev, S_IFCHR)) == NULL)
212		lastname = "??";
213	return (lastname);
214}
215
216void
217usage(void)
218{
219	(void)fprintf(stderr,
220	    "usage: lastcomm [-f file] [command ...] [user ...] [terminal ...]\n");
221	exit(1);
222}
223