lastcomm.c revision 1.25 
1/*	$OpenBSD: lastcomm.c,v 1.25 2017/06/07 20:53:59 bluhm 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 <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		case '?':
81		default:
82			usage();
83		}
84	argc -= optind;
85	argv += optind;
86
87	/* Open the file. */
88	if ((fp = fopen(acctfile, "r")) == NULL || fstat(fileno(fp), &sb))
89		err(1, "%s", acctfile);
90
91	/*
92	 * Round off to integral number of accounting records, probably
93	 * not necessary, but it doesn't hurt.
94	 */
95	size = sb.st_size - sb.st_size % sizeof(struct acct);
96
97	/* Check if any records to display. */
98	if (size < sizeof(struct acct))
99		exit(0);
100
101	/*
102	 * Seek to before the last entry in the file; use lseek(2) in case
103	 * the file is bigger than a "long".
104	 */
105	size -= sizeof(struct acct);
106	if (lseek(fileno(fp), size, SEEK_SET) == -1)
107		err(1, "%s", acctfile);
108
109	for (;;) {
110		if (fread(&ab, sizeof(struct acct), 1, fp) != 1)
111			err(1, "%s", acctfile);
112
113		if (ab.ac_comm[0] == '\0') {
114			ab.ac_comm[0] = '?';
115			ab.ac_comm[1] = '\0';
116		} else
117			for (p = &ab.ac_comm[0];
118			    p < &ab.ac_comm[sizeof ab.ac_comm] && *p; ++p)
119				if (!isprint((unsigned char)*p))
120					*p = '?';
121		if (!*argv || requested(argv, &ab))
122		{
123			t = expand(ab.ac_utime) + expand(ab.ac_stime);
124			(void)printf("%-*.*s %-7s %-*.*s %-*.*s %6.2f secs %.16s",
125			    (int)sizeof ab.ac_comm,
126			    (int)sizeof ab.ac_comm,
127			    ab.ac_comm, flagbits(ab.ac_flag), UT_NAMESIZE,
128			    UT_NAMESIZE, user_from_uid(ab.ac_uid, 0),
129			    UT_LINESIZE, UT_LINESIZE, getdev(ab.ac_tty),
130			    t / (double)AHZ, ctime(&ab.ac_btime));
131			delta = expand(ab.ac_etime) / (double)AHZ;
132			printf(" (%1.0f:%02.0f:%05.2f)\n",
133			    delta / SECSPERHOUR,
134			    fmod(delta, (double)SECSPERHOUR) / SECSPERMIN,
135			    fmod(delta, (double)SECSPERMIN));
136		}
137
138		if (size == 0)
139			break;
140		/* seek to previous entry */
141		if (fseek(fp, 2 * -(long)sizeof(struct acct), SEEK_CUR) == -1)
142			err(1, "%s", acctfile);
143		size -= sizeof(struct acct);
144	}
145	exit(0);
146}
147
148time_t
149expand(u_int t)
150{
151	time_t nt;
152
153	nt = t & 017777;
154	t >>= 13;
155	while (t) {
156		t--;
157		nt <<= 3;
158	}
159	return (nt);
160}
161
162char *
163flagbits(int f)
164{
165	static char flags[20] = "-";
166	char *p;
167
168#define	BIT(flag, ch)	if (f & flag) *p++ = ch
169
170	p = flags + 1;
171	BIT(ASU, 'S');
172	BIT(AFORK, 'F');
173	BIT(ACOMPAT, 'C');
174	BIT(ACORE, 'D');
175	BIT(AXSIG, 'X');
176	BIT(APLEDGE, 'P');
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, sizeof acp->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