xref: /freebsd/usr.bin/ktrdump/ktrdump.c (revision ee2ea5ceafed78a5bd9810beb9e3ca927180c226)
1 /*-
2  * Copyright (c) 2002 Jake Burkholder
3  * 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  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/types.h>
31 #include <sys/ktr.h>
32 
33 #include <err.h>
34 #include <fcntl.h>
35 #include <kvm.h>
36 #include <limits.h>
37 #include <nlist.h>
38 #include <stdint.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <unistd.h>
43 
44 #define	SBUFLEN	128
45 #define	USAGE \
46 	"usage: ktrdump [-c] [-f] [-t] [-e execfile] [-m corefile] [-o outfile]"
47 
48 extern char *optarg;
49 extern int optind;
50 
51 static void usage(void);
52 
53 static struct nlist nl[] = {
54 	{ "_ktr_version" },
55 	{ "_ktr_entries" },
56 	{ "_ktr_idx" },
57 	{ "_ktr_buf" },
58 	{ NULL }
59 };
60 
61 static int cflag;
62 static int eflag;
63 static int fflag;
64 static int mflag;
65 static int tflag;
66 
67 static char corefile[PATH_MAX];
68 static char execfile[PATH_MAX];
69 
70 static char desc[SBUFLEN];
71 static char errbuf[_POSIX2_LINE_MAX];
72 static char fbuf[PATH_MAX];
73 static char obuf[PATH_MAX];
74 static char sbuf[KTR_PARMS][SBUFLEN];
75 
76 /*
77  * Reads the ktr trace buffer from kernel memory and prints the trace entries.
78  */
79 int
80 main(int ac, char **av)
81 {
82 	u_long parms[KTR_PARMS];
83 	struct ktr_entry *buf;
84 	kvm_t *kd;
85 	FILE *out;
86 	char *p;
87 	int version;
88 	int entries;
89 	int index;
90 	int parm;
91 	int c;
92 	int i;
93 	int n;
94 
95 	/*
96 	 * Parse commandline arguments.
97 	 */
98 	out = stdout;
99 	while ((c = getopt(ac, av, "cfte:m:o:")) != -1)
100 		switch (c) {
101 		case 'c':
102 			cflag = 1;
103 			break;
104 		case 'e':
105 			strcpy(execfile, optarg);
106 			eflag = 1;
107 			break;
108 		case 'f':
109 			fflag = 1;
110 			break;
111 		case 'm':
112 			strcpy(corefile, optarg);
113 			mflag = 1;
114 			break;
115 		case 'o':
116 			if ((out = fopen(optarg, "w")) == NULL)
117 				err(1, "%s", optarg);
118 			break;
119 		case 't':
120 			tflag = 1;
121 			break;
122 		case '?':
123 		default:
124 			usage();
125 		}
126 	ac -= optind;
127 	av += optind;
128 	if (ac != 0)
129 		usage();
130 
131 	/*
132 	 * Open our execfile and corefile, resolve needed symbols and read in
133 	 * the trace buffer.
134 	 */
135 	if ((kd = kvm_openfiles(eflag ? execfile : NULL,
136 	    mflag ? corefile : NULL, NULL, O_RDONLY, errbuf)) == NULL)
137 		errx(1, "%s", errbuf);
138 	if (kvm_nlist(kd, nl) != 0 ||
139 	    kvm_read(kd, nl[0].n_value, &version, sizeof(version)) == -1)
140 		errx(1, "%s", kvm_geterr(kd));
141 	if (version != KTR_VERSION)
142 		errx(1, "ktr version mismatch");
143 	if (kvm_read(kd, nl[1].n_value, &entries, sizeof(entries)) == -1)
144 		errx(1, "%s", kvm_geterr(kd));
145 	if ((buf = malloc(sizeof(*buf) * entries)) == NULL)
146 		err(1, NULL);
147 	if (kvm_read(kd, nl[2].n_value, &index, sizeof(index)) == -1 ||
148 	    kvm_read(kd, nl[3].n_value, buf, sizeof(*buf) * entries) == -1)
149 		errx(1, "%s", kvm_geterr(kd));
150 
151 	/*
152 	 * Print a nice header.
153 	 */
154 	fprintf(out, "%-6s ", "index");
155 	if (cflag)
156 		fprintf(out, "%-3s ", "cpu");
157 	if (tflag)
158 		fprintf(out, "%-16s ", "timestamp");
159 	if (fflag)
160 		fprintf(out, "%-32s ", "file and line");
161 	fprintf(out, "%s", "trace");
162 	fprintf(out, "\n");
163 
164 	fprintf(out, "------ ");
165 	if (cflag)
166 		fprintf(out, "--- ");
167 	if (tflag)
168 		fprintf(out, "---------------- ");
169 	if (fflag)
170 		fprintf(out, "---------------------------------------- ");
171 	fprintf(out, "----- ");
172 	fprintf(out, "\n");
173 
174 	/*
175 	 * Now tear through the trace buffer.
176 	 */
177 	i = (index - 1) & (entries - 1);
178 	for (;;) {
179 		if (buf[i].ktr_desc == NULL)
180 			break;
181 		if (kvm_read(kd, (u_long)buf[i].ktr_desc, desc,
182 		    sizeof(desc)) == -1)
183 			errx(1, "%s", kvm_geterr(kd));
184 		desc[sizeof(desc) - 1] = '\0';
185 		parm = 0;
186 		for (p = desc; (c = *p++) != '\0';) {
187 			if (c != '%')
188 				continue;
189 			if ((c = *p++) == '\0')
190 				break;
191 			if (parm == KTR_PARMS)
192 				errx(1, "too many parameters");
193 			switch (c) {
194 			case 's':
195 				if (kvm_read(kd, (u_long)buf[i].ktr_parms[parm],
196 				    sbuf[parm], sizeof(sbuf[parm])) == -1)
197 					strcpy(sbuf[parm], "(null)");
198 				sbuf[parm][sizeof(sbuf[0]) - 1] = '\0';
199 				parms[parm] = (u_long)sbuf[parm];
200 				parm++;
201 				break;
202 			default:
203 				parms[parm] = buf[i].ktr_parms[parm];
204 				parm++;
205 				break;
206 			}
207 		}
208 		fprintf(out, "%6d ", i);
209 		if (cflag)
210 			fprintf(out, "%3d ", buf[i].ktr_cpu);
211 		if (tflag)
212 			fprintf(out, "%16ju ",
213 			    (uintmax_t)buf[i].ktr_timestamp);
214 		if (fflag) {
215 			if (kvm_read(kd, (u_long)buf[i].ktr_file, fbuf,
216 			    sizeof(fbuf)) == -1)
217 				strcpy(fbuf, "(null)");
218 			snprintf(obuf, sizeof(obuf), "%s:%d", fbuf,
219 			    buf[i].ktr_line);
220 			fprintf(out, "%-40s ", obuf);
221 		}
222 		fprintf(out, desc, parms[0], parms[1], parms[2], parms[3],
223 		    parms[4], parms[5]);
224 		fprintf(out, "\n");
225 		if (i == index)
226 			break;
227 		i = (i - 1) & (entries - 1);
228 	}
229 
230 	return (0);
231 }
232 
233 static void
234 usage(void)
235 {
236 	errx(1, USAGE);
237 }
238