xref: /openbsd/usr.bin/lastcomm/lastcomm.c (revision 09467b48)
1 /*	$OpenBSD: lastcomm.c,v 1.29 2019/09/09 20:02:27 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 
49 time_t	 expand(u_int);
50 char	*flagbits(int);
51 char	*getdev(dev_t);
52 int	 requested(char *[], struct acct *);
53 void	 usage(void);
54 
55 #define SECSPERMIN	(60)
56 #define SECSPERHOUR	(60 * 60)
57 
58 int
59 main(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 
148 time_t
149 expand(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 
162 char *
163 flagbits(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(AFORK, 'F');
172 	BIT(AMAP, 'M');
173 	BIT(ACORE, 'D');
174 	BIT(AXSIG, 'X');
175 	BIT(APLEDGE, 'P');
176 	BIT(ATRAP, 'T');
177 	BIT(AUNVEIL, 'U');
178 	*p = '\0';
179 	return (flags);
180 }
181 
182 int
183 requested(char *argv[], struct acct *acp)
184 {
185 	do {
186 		if (!strcmp(user_from_uid(acp->ac_uid, 0), *argv))
187 			return (1);
188 		if (!strcmp(getdev(acp->ac_tty), *argv))
189 			return (1);
190 		if (!strncmp(acp->ac_comm, *argv, sizeof acp->ac_comm))
191 			return (1);
192 	} while (*++argv);
193 	return (0);
194 }
195 
196 char *
197 getdev(dev_t dev)
198 {
199 	static dev_t lastdev = (dev_t)-1;
200 	static char *lastname;
201 
202 	if (dev == NODEV)			/* Special case. */
203 		return ("__");
204 	if (dev == lastdev)			/* One-element cache. */
205 		return (lastname);
206 	lastdev = dev;
207 	if ((lastname = devname(dev, S_IFCHR)) == NULL)
208 		lastname = "??";
209 	return (lastname);
210 }
211 
212 void
213 usage(void)
214 {
215 	(void)fprintf(stderr,
216 	    "usage: lastcomm [-f file] [command ...] [user ...] [terminal ...]\n");
217 	exit(1);
218 }
219