xref: /freebsd/usr.bin/ktrdump/ktrdump.c (revision 6ae1554a5d9b318f8ad53ccc39fa5a961403da73)
1 /*-
2  * Copyright (c) 2002 Jake Burkholder
3  * Copyright (c) 2004 Robert Watson
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/types.h>
32 #include <sys/ktr.h>
33 #include <sys/mman.h>
34 #include <sys/stat.h>
35 
36 #include <err.h>
37 #include <fcntl.h>
38 #include <kvm.h>
39 #include <limits.h>
40 #include <nlist.h>
41 #include <stdint.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46 
47 #define	SBUFLEN	128
48 #define	USAGE \
49 	"usage: ktrdump [-cfqrtH] [-i ktrfile] [-M core] [-N system] [-o outfile]\n"
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 fflag;
63 static int Mflag;
64 static int Nflag;
65 static int qflag;
66 static int rflag;
67 static int tflag;
68 static int iflag;
69 static int hflag;
70 
71 static char corefile[PATH_MAX];
72 static char execfile[PATH_MAX];
73 
74 static char desc[SBUFLEN];
75 static char errbuf[_POSIX2_LINE_MAX];
76 static char fbuf[PATH_MAX];
77 static char obuf[PATH_MAX];
78 static char sbuf[KTR_PARMS][SBUFLEN];
79 
80 /*
81  * Reads the ktr trace buffer from kernel memory and prints the trace entries.
82  */
83 int
84 main(int ac, char **av)
85 {
86 	u_long parms[KTR_PARMS];
87 	struct ktr_entry *buf;
88 	uintmax_t tlast, tnow;
89 	unsigned long bufptr;
90 	struct stat sb;
91 	kvm_t *kd;
92 	FILE *out;
93 	char *p;
94 	int version;
95 	int entries;
96 	int index, index2;
97 	int parm;
98 	int in;
99 	int c;
100 	int i = 0;
101 
102 	/*
103 	 * Parse commandline arguments.
104 	 */
105 	out = stdout;
106 	while ((c = getopt(ac, av, "cfqrtHe:i:m:M:N:o:")) != -1)
107 		switch (c) {
108 		case 'c':
109 			cflag = 1;
110 			break;
111 		case 'N':
112 		case 'e':
113 			if (strlcpy(execfile, optarg, sizeof(execfile))
114 			    >= sizeof(execfile))
115 				errx(1, "%s: File name too long", optarg);
116 			Nflag = 1;
117 			break;
118 		case 'f':
119 			fflag = 1;
120 			break;
121 		case 'i':
122 			iflag = 1;
123 			if ((in = open(optarg, O_RDONLY)) == -1)
124 				err(1, "%s", optarg);
125 			break;
126 		case 'M':
127 		case 'm':
128 			if (strlcpy(corefile, optarg, sizeof(corefile))
129 			    >= sizeof(corefile))
130 				errx(1, "%s: File name too long", optarg);
131 			Mflag = 1;
132 			break;
133 		case 'o':
134 			if ((out = fopen(optarg, "w")) == NULL)
135 				err(1, "%s", optarg);
136 			break;
137 		case 'q':
138 			qflag++;
139 			break;
140 		case 'r':
141 			rflag = 1;
142 			break;
143 		case 't':
144 			tflag = 1;
145 			break;
146 		case 'H':
147 			hflag = 1;
148 			break;
149 		case '?':
150 		default:
151 			usage();
152 		}
153 	ac -= optind;
154 	av += optind;
155 	if (ac != 0)
156 		usage();
157 
158 	/*
159 	 * Open our execfile and corefile, resolve needed symbols and read in
160 	 * the trace buffer.
161 	 */
162 	if ((kd = kvm_openfiles(Nflag ? execfile : NULL,
163 	    Mflag ? corefile : NULL, NULL, O_RDONLY, errbuf)) == NULL)
164 		errx(1, "%s", errbuf);
165 	if (kvm_nlist(kd, nl) != 0 ||
166 	    kvm_read(kd, nl[0].n_value, &version, sizeof(version)) == -1)
167 		errx(1, "%s", kvm_geterr(kd));
168 	if (version != KTR_VERSION)
169 		errx(1, "ktr version mismatch");
170 	if (iflag) {
171 		if (fstat(in, &sb) == -1)
172 			errx(1, "stat");
173 		entries = sb.st_size / sizeof(*buf);
174 		index = 0;
175 		buf = mmap(NULL, sb.st_size, PROT_READ, MAP_SHARED, in, 0);
176 		if (buf == MAP_FAILED)
177 			errx(1, "mmap");
178 	} else {
179 		if (kvm_read(kd, nl[1].n_value, &entries, sizeof(entries))
180 		    == -1)
181 			errx(1, "%s", kvm_geterr(kd));
182 		if ((buf = malloc(sizeof(*buf) * entries)) == NULL)
183 			err(1, NULL);
184 		if (kvm_read(kd, nl[2].n_value, &index, sizeof(index)) == -1 ||
185 		    kvm_read(kd, nl[3].n_value, &bufptr,
186 		    sizeof(bufptr)) == -1 ||
187 		    kvm_read(kd, bufptr, buf, sizeof(*buf) * entries) == -1 ||
188 		    kvm_read(kd, nl[2].n_value, &index2, sizeof(index2)) == -1)
189 			errx(1, "%s", kvm_geterr(kd));
190 	}
191 
192 	/*
193 	 * Print a nice header.
194 	 */
195 	if (!qflag) {
196 		fprintf(out, "%-6s ", "index");
197 		if (cflag)
198 			fprintf(out, "%-3s ", "cpu");
199 		if (tflag)
200 			fprintf(out, "%-16s ", "timestamp");
201 		if (fflag)
202 			fprintf(out, "%-40s ", "file and line");
203 		if (hflag)
204 			fprintf(out, "%-18s ", "tid");
205 		fprintf(out, "%s", "trace");
206 		fprintf(out, "\n");
207 
208 		fprintf(out, "------ ");
209 		if (cflag)
210 			fprintf(out, "--- ");
211 		if (tflag)
212 			fprintf(out, "---------------- ");
213 		if (fflag)
214 			fprintf(out,
215 			    "---------------------------------------- ");
216 		if (hflag)
217 			fprintf(out, "------------------ ");
218 		fprintf(out, "----- ");
219 		fprintf(out, "\n");
220 	}
221 
222 	/*
223 	 * Now tear through the trace buffer.
224 	 */
225 	if (!iflag) {
226 		i = index - 1;
227 		if (i < 0)
228 			i = entries - 1;
229 	}
230 	tlast = -1;
231 	for (;;) {
232 		if (buf[i].ktr_desc == NULL)
233 			break;
234 		if (kvm_read(kd, (u_long)buf[i].ktr_desc, desc,
235 		    sizeof(desc)) == -1)
236 			errx(1, "%s", kvm_geterr(kd));
237 		desc[sizeof(desc) - 1] = '\0';
238 		parm = 0;
239 		for (p = desc; (c = *p++) != '\0';) {
240 			if (c != '%')
241 				continue;
242 next:			if ((c = *p++) == '\0')
243 				break;
244 			if (parm == KTR_PARMS)
245 				errx(1, "too many parameters in \"%s\"", desc);
246 			switch (c) {
247 			case '0': case '1': case '2': case '3': case '4':
248 			case '5': case '6': case '7': case '8': case '9':
249 			case '#': case '-': case ' ': case '+': case '\'':
250 			case 'h': case 'l': case 'j': case 't': case 'z':
251 			case 'q': case 'L': case '.':
252 				goto next;
253 			case 's':
254 				if (kvm_read(kd, (u_long)buf[i].ktr_parms[parm],
255 				    sbuf[parm], sizeof(sbuf[parm])) == -1)
256 					strcpy(sbuf[parm], "(null)");
257 				sbuf[parm][sizeof(sbuf[0]) - 1] = '\0';
258 				parms[parm] = (u_long)sbuf[parm];
259 				parm++;
260 				break;
261 			default:
262 				parms[parm] = buf[i].ktr_parms[parm];
263 				parm++;
264 				break;
265 			}
266 		}
267 		fprintf(out, "%6d ", i);
268 		if (cflag)
269 			fprintf(out, "%3d ", buf[i].ktr_cpu);
270 		if (tflag) {
271 			tnow = (uintmax_t)buf[i].ktr_timestamp;
272 			if (rflag) {
273 				if (tlast == -1)
274 					tlast = tnow;
275 				fprintf(out, "%16ju ", !iflag ? tlast - tnow :
276 				    tnow - tlast);
277 				tlast = tnow;
278 			} else
279 				fprintf(out, "%16ju ", tnow);
280 		}
281 		if (fflag) {
282 			if (kvm_read(kd, (u_long)buf[i].ktr_file, fbuf,
283 			    sizeof(fbuf)) == -1)
284 				strcpy(fbuf, "(null)");
285 			snprintf(obuf, sizeof(obuf), "%s:%d", fbuf,
286 			    buf[i].ktr_line);
287 			fprintf(out, "%-40s ", obuf);
288 		}
289 		if (hflag)
290 			fprintf(out, "%p ", buf[i].ktr_thread);
291 		fprintf(out, desc, parms[0], parms[1], parms[2], parms[3],
292 		    parms[4], parms[5]);
293 		fprintf(out, "\n");
294 		if (!iflag) {
295 			/*
296 			 * 'index' and 'index2' are the values of 'ktr_idx'
297 			 * before and after the KTR buffer was copied into
298 			 * 'buf'. Since the KTR entries between 'index' and
299 			 * 'index2' were in flux while the KTR buffer was
300 			 * being copied to userspace we don't dump them.
301 			 */
302 			if (i == index2)
303 				break;
304 			if (--i < 0)
305 				i = entries - 1;
306 		} else {
307 			if (++i == entries)
308 				break;
309 		}
310 	}
311 
312 	return (0);
313 }
314 
315 static void
316 usage(void)
317 {
318 
319 	fprintf(stderr, USAGE);
320 	exit(1);
321 }
322