xref: /openbsd/usr.bin/lastcomm/lastcomm.c (revision 898184e3)
1 /*	$OpenBSD: lastcomm.c,v 1.17 2009/10/27 23:59:39 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>
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 <tzfile.h>
46 #include <unistd.h>
47 #include <utmp.h>
48 #include <pwd.h>
49 #include "pathnames.h"
50 
51 time_t	 expand(u_int);
52 char	*flagbits(int);
53 char	*getdev(dev_t);
54 int	 requested(char *[], struct acct *);
55 void	 usage(void);
56 
57 int
58 main(int argc, char *argv[])
59 {
60 	char *p;
61 	struct acct ab;
62 	struct stat sb;
63 	FILE *fp;
64 	off_t size;
65 	time_t t;
66 	double delta;
67 	int ch;
68 	char *acctfile;
69 
70 	acctfile = _PATH_ACCT;
71 	while ((ch = getopt(argc, argv, "f:")) != -1)
72 		switch((char)ch) {
73 		case 'f':
74 			acctfile = optarg;
75 			break;
76 		case '?':
77 		default:
78 			usage();
79 		}
80 	argc -= optind;
81 	argv += optind;
82 
83 	/* Open the file. */
84 	if ((fp = fopen(acctfile, "r")) == NULL || fstat(fileno(fp), &sb))
85 		err(1, "%s", acctfile);
86 
87 	/*
88 	 * Round off to integral number of accounting records, probably
89 	 * not necessary, but it doesn't hurt.
90 	 */
91 	size = sb.st_size - sb.st_size % sizeof(struct acct);
92 
93 	/* Check if any records to display. */
94 	if (size < sizeof(struct acct))
95 		exit(0);
96 
97 	/*
98 	 * Seek to before the last entry in the file; use lseek(2) in case
99 	 * the file is bigger than a "long".
100 	 */
101 	size -= sizeof(struct acct);
102 	if (lseek(fileno(fp), size, SEEK_SET) == -1)
103 		err(1, "%s", acctfile);
104 
105 	for (;;) {
106 		if (fread(&ab, sizeof(struct acct), 1, fp) != 1)
107 			err(1, "%s", acctfile);
108 
109 		if (ab.ac_comm[0] == '\0') {
110 			ab.ac_comm[0] = '?';
111 			ab.ac_comm[1] = '\0';
112 		} else
113 			for (p = &ab.ac_comm[0];
114 			    p < &ab.ac_comm[fldsiz(acct, ac_comm)] && *p; ++p)
115 				if (!isprint(*p))
116 					*p = '?';
117 		if (!*argv || requested(argv, &ab))
118 		{
119 			t = expand(ab.ac_utime) + expand(ab.ac_stime);
120 			(void)printf("%-*.*s %-7s %-*.*s %-*.*s %6.2f secs %.16s",
121 			    (int)fldsiz(acct, ac_comm),
122 			    (int)fldsiz(acct, ac_comm),
123 			    ab.ac_comm, flagbits(ab.ac_flag), UT_NAMESIZE,
124 			    UT_NAMESIZE, user_from_uid(ab.ac_uid, 0),
125 			    UT_LINESIZE, UT_LINESIZE, getdev(ab.ac_tty),
126 			    t / (double)AHZ, ctime(&ab.ac_btime));
127 			delta = expand(ab.ac_etime) / (double)AHZ;
128 			printf(" (%1.0f:%02.0f:%05.2f)\n",
129 			    delta / SECSPERHOUR,
130 			    fmod(delta, (double)SECSPERHOUR) / SECSPERMIN,
131 			    fmod(delta, (double)SECSPERMIN));
132 		}
133 
134 		if (size == 0)
135 			break;
136 		/* seek to previous entry */
137 		if (fseek(fp, 2 * -(long)sizeof(struct acct), SEEK_CUR) == -1)
138 			err(1, "%s", acctfile);
139 		size -= sizeof(struct acct);
140 	}
141 	exit(0);
142 }
143 
144 time_t
145 expand(u_int t)
146 {
147 	time_t nt;
148 
149 	nt = t & 017777;
150 	t >>= 13;
151 	while (t) {
152 		t--;
153 		nt <<= 3;
154 	}
155 	return (nt);
156 }
157 
158 char *
159 flagbits(int f)
160 {
161 	static char flags[20] = "-";
162 	char *p;
163 
164 #define	BIT(flag, ch)	if (f & flag) *p++ = ch
165 
166 	p = flags + 1;
167 	BIT(ASU, 'S');
168 	BIT(AFORK, 'F');
169 	BIT(ACOMPAT, 'C');
170 	BIT(ACORE, 'D');
171 	BIT(AXSIG, 'X');
172 	*p = '\0';
173 	return (flags);
174 }
175 
176 int
177 requested(char *argv[], struct acct *acp)
178 {
179 	do {
180 		if (!strcmp(user_from_uid(acp->ac_uid, 0), *argv))
181 			return (1);
182 		if (!strcmp(getdev(acp->ac_tty), *argv))
183 			return (1);
184 		if (!strncmp(acp->ac_comm, *argv, fldsiz(acct, ac_comm)))
185 			return (1);
186 	} while (*++argv);
187 	return (0);
188 }
189 
190 char *
191 getdev(dev_t dev)
192 {
193 	static dev_t lastdev = (dev_t)-1;
194 	static char *lastname;
195 
196 	if (dev == NODEV)			/* Special case. */
197 		return ("__");
198 	if (dev == lastdev)			/* One-element cache. */
199 		return (lastname);
200 	lastdev = dev;
201 	if ((lastname = devname(dev, S_IFCHR)) == NULL)
202 		lastname = "??";
203 	return (lastname);
204 }
205 
206 void
207 usage(void)
208 {
209 	(void)fprintf(stderr,
210 	    "usage: lastcomm [-f file] [command ...] [user ...] [terminal ...]\n");
211 	exit(1);
212 }
213