1/*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if 0
31#ifndef lint
32static const char copyright[] =
33"@(#) Copyright (c) 1991, 1993\n\
34 The Regents of the University of California. All rights reserved.\n";
35#endif /* not lint */
36
37#ifndef lint
38static const char sccsid[] = "@(#)dmesg.c 8.1 (Berkeley) 6/5/93";
39#endif /* not lint */
40#endif
41#include <sys/cdefs.h>
|
42__FBSDID("$FreeBSD: head/sbin/dmesg/dmesg.c 227081 2011-11-04 13:36:02Z ed $");
|
| 42__FBSDID("$FreeBSD: head/sbin/dmesg/dmesg.c 250430 2013-05-10 03:42:48Z eadler $"); |
43
44#include <sys/types.h>
45#include <sys/msgbuf.h>
46#include <sys/sysctl.h>
47
48#include <ctype.h>
49#include <err.h>
50#include <errno.h>
51#include <fcntl.h>
52#include <kvm.h>
53#include <limits.h>
54#include <locale.h>
55#include <nlist.h>
56#include <stdio.h>
|
| 57#include <stdbool.h> |
58#include <stdlib.h>
59#include <string.h>
60#include <unistd.h>
61#include <vis.h>
62#include <sys/syslog.h>
63
64static struct nlist nl[] = {
65#define X_MSGBUF 0
66 { "_msgbufp", 0, 0, 0, 0 },
67 { NULL, 0, 0, 0, 0 },
68};
69
70void usage(void) __dead2;
71
72#define KREAD(addr, var) \
73 kvm_read(kd, addr, &var, sizeof(var)) != sizeof(var)
74
75int
76main(int argc, char *argv[])
77{
78 struct msgbuf *bufp, cur;
79 char *bp, *ep, *memf, *nextp, *nlistf, *p, *q, *visbp;
80 kvm_t *kd;
81 size_t buflen, bufpos;
82 long pri;
|
82 int all, ch;
|
83 int ch, clear;
84 bool all; |
85
|
84 all = 0;
|
86 all = false;
87 clear = false; |
88 (void) setlocale(LC_CTYPE, "");
89 memf = nlistf = NULL;
|
87 while ((ch = getopt(argc, argv, "aM:N:")) != -1)
|
| 90 while ((ch = getopt(argc, argv, "acM:N:")) != -1) |
91 switch(ch) {
92 case 'a':
|
90 all++;
|
| 93 all = true; |
94 break;
|
95 case 'c':
96 clear = true;
97 break; |
98 case 'M':
99 memf = optarg;
100 break;
101 case 'N':
102 nlistf = optarg;
103 break;
104 case '?':
105 default:
106 usage();
107 }
108 argc -= optind;
109 if (argc != 0)
110 usage();
111
112 if (memf == NULL) {
113 /*
114 * Running kernel. Use sysctl. This gives an unwrapped
115 * buffer as a side effect.
116 */
117 if (sysctlbyname("kern.msgbuf", NULL, &buflen, NULL, 0) == -1)
118 err(1, "sysctl kern.msgbuf");
119 if ((bp = malloc(buflen + 2)) == NULL)
120 errx(1, "malloc failed");
121 if (sysctlbyname("kern.msgbuf", bp, &buflen, NULL, 0) == -1)
122 err(1, "sysctl kern.msgbuf");
123 } else {
124 /* Read in kernel message buffer and do sanity checks. */
125 kd = kvm_open(nlistf, memf, NULL, O_RDONLY, "dmesg");
126 if (kd == NULL)
127 exit (1);
128 if (kvm_nlist(kd, nl) == -1)
129 errx(1, "kvm_nlist: %s", kvm_geterr(kd));
130 if (nl[X_MSGBUF].n_type == 0)
131 errx(1, "%s: msgbufp not found",
132 nlistf ? nlistf : "namelist");
133 if (KREAD(nl[X_MSGBUF].n_value, bufp) || KREAD((long)bufp, cur))
134 errx(1, "kvm_read: %s", kvm_geterr(kd));
135 if (cur.msg_magic != MSG_MAGIC)
136 errx(1, "kernel message buffer has different magic "
137 "number");
138 if ((bp = malloc(cur.msg_size + 2)) == NULL)
139 errx(1, "malloc failed");
140
141 /* Unwrap the circular buffer to start from the oldest data. */
142 bufpos = MSGBUF_SEQ_TO_POS(&cur, cur.msg_wseq);
143 if (kvm_read(kd, (long)&cur.msg_ptr[bufpos], bp,
144 cur.msg_size - bufpos) != (ssize_t)(cur.msg_size - bufpos))
145 errx(1, "kvm_read: %s", kvm_geterr(kd));
146 if (bufpos != 0 && kvm_read(kd, (long)cur.msg_ptr,
147 &bp[cur.msg_size - bufpos], bufpos) != (ssize_t)bufpos)
148 errx(1, "kvm_read: %s", kvm_geterr(kd));
149 kvm_close(kd);
150 buflen = cur.msg_size;
151 }
152
153 /*
154 * Ensure that the buffer ends with a newline and a \0 to avoid
155 * complications below. We left space above.
156 */
157 if (buflen == 0 || bp[buflen - 1] != '\n')
158 bp[buflen++] = '\n';
159 bp[buflen] = '\0';
160
161 if ((visbp = malloc(4 * buflen + 1)) == NULL)
162 errx(1, "malloc failed");
163
164 /*
165 * The message buffer is circular, but has been unwrapped so that
166 * the oldest data comes first. The data will be preceded by \0's
167 * if the message buffer was not full.
168 */
169 p = bp;
170 ep = &bp[buflen];
171 if (*p == '\0') {
172 /* Strip leading \0's */
173 while (*p == '\0')
174 p++;
175 } else if (!all) {
176 /* Skip the first line, since it is probably incomplete. */
177 p = memchr(p, '\n', ep - p);
178 p++;
179 }
180 for (; p < ep; p = nextp) {
181 nextp = memchr(p, '\n', ep - p);
182 nextp++;
183
184 /* Skip ^<[0-9]+> syslog sequences. */
185 if (*p == '<' && isdigit(*(p+1))) {
186 errno = 0;
187 pri = strtol(p + 1, &q, 10);
188 if (*q == '>' && pri >= 0 && pri < INT_MAX &&
189 errno == 0) {
190 if (LOG_FAC(pri) != LOG_KERN && !all)
191 continue;
192 p = q + 1;
193 }
194 }
195
196 (void)strvisx(visbp, p, nextp - p, 0);
197 (void)printf("%s", visbp);
198 }
|
199 if (clear)
200 if (sysctlbyname("kern.msgbuf_clear", NULL, NULL, &clear, sizeof(int)))
201 err(1, "sysctl kern.msgbuf_clear");
202 |
203 exit(0);
204}
205
206void
207usage(void)
208{
|
199 (void)fprintf(stderr, "usage: dmesg [-a] [-M core [-N system]]\n");
|
| 209 fprintf(stderr, "usage: dmesg [-ac] [-M core [-N system]]\n"); |
210 exit(1);
211}
|