1 /*
2  * Copyright (C) 2009, Steven Rostedt <srostedt@redhat.com>
3  *
4  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 of the License (not later!)
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  *
19  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
20  */
21 #include <dirent.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <stdarg.h>
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <sys/wait.h>
29 #include <sys/mman.h>
30 #include <pthread.h>
31 #include <fcntl.h>
32 #include <unistd.h>
33 #include <errno.h>
34 
35 #include "../perf.h"
36 #include "util.h"
37 #include "trace-event.h"
38 #include "debug.h"
39 
40 static int input_fd;
41 
42 static ssize_t trace_data_size;
43 static bool repipe;
44 
45 static int __do_read(int fd, void *buf, int size)
46 {
47 	int rsize = size;
48 
49 	while (size) {
50 		int ret = read(fd, buf, size);
51 
52 		if (ret <= 0)
53 			return -1;
54 
55 		if (repipe) {
56 			int retw = write(STDOUT_FILENO, buf, ret);
57 
58 			if (retw <= 0 || retw != ret) {
59 				pr_debug("repiping input file");
60 				return -1;
61 			}
62 		}
63 
64 		size -= ret;
65 		buf += ret;
66 	}
67 
68 	return rsize;
69 }
70 
71 static int do_read(void *data, int size)
72 {
73 	int r;
74 
75 	r = __do_read(input_fd, data, size);
76 	if (r <= 0) {
77 		pr_debug("reading input file (size expected=%d received=%d)",
78 			 size, r);
79 		return -1;
80 	}
81 
82 	trace_data_size += r;
83 
84 	return r;
85 }
86 
87 /* If it fails, the next read will report it */
88 static void skip(int size)
89 {
90 	char buf[BUFSIZ];
91 	int r;
92 
93 	while (size) {
94 		r = size > BUFSIZ ? BUFSIZ : size;
95 		do_read(buf, r);
96 		size -= r;
97 	};
98 }
99 
100 static unsigned int read4(struct pevent *pevent)
101 {
102 	unsigned int data;
103 
104 	if (do_read(&data, 4) < 0)
105 		return 0;
106 	return __data2host4(pevent, data);
107 }
108 
109 static unsigned long long read8(struct pevent *pevent)
110 {
111 	unsigned long long data;
112 
113 	if (do_read(&data, 8) < 0)
114 		return 0;
115 	return __data2host8(pevent, data);
116 }
117 
118 static char *read_string(void)
119 {
120 	char buf[BUFSIZ];
121 	char *str = NULL;
122 	int size = 0;
123 	off_t r;
124 	char c;
125 
126 	for (;;) {
127 		r = read(input_fd, &c, 1);
128 		if (r < 0) {
129 			pr_debug("reading input file");
130 			goto out;
131 		}
132 
133 		if (!r) {
134 			pr_debug("no data");
135 			goto out;
136 		}
137 
138 		if (repipe) {
139 			int retw = write(STDOUT_FILENO, &c, 1);
140 
141 			if (retw <= 0 || retw != r) {
142 				pr_debug("repiping input file string");
143 				goto out;
144 			}
145 		}
146 
147 		buf[size++] = c;
148 
149 		if (!c)
150 			break;
151 	}
152 
153 	trace_data_size += size;
154 
155 	str = malloc(size);
156 	if (str)
157 		memcpy(str, buf, size);
158 out:
159 	return str;
160 }
161 
162 static int read_proc_kallsyms(struct pevent *pevent)
163 {
164 	unsigned int size;
165 
166 	size = read4(pevent);
167 	if (!size)
168 		return 0;
169 	/*
170 	 * Just skip it, now that we configure libtraceevent to use the
171 	 * tools/perf/ symbol resolver.
172 	 *
173 	 * We need to skip it so that we can continue parsing old perf.data
174 	 * files, that contains this /proc/kallsyms payload.
175 	 *
176 	 * Newer perf.data files will have just the 4-bytes zeros "kallsyms
177 	 * payload", so that older tools can continue reading it and interpret
178 	 * it as "no kallsyms payload is present".
179 	 */
180 	lseek(input_fd, size, SEEK_CUR);
181 	trace_data_size += size;
182 	return 0;
183 }
184 
185 static int read_ftrace_printk(struct pevent *pevent)
186 {
187 	unsigned int size;
188 	char *buf;
189 
190 	/* it can have 0 size */
191 	size = read4(pevent);
192 	if (!size)
193 		return 0;
194 
195 	buf = malloc(size);
196 	if (buf == NULL)
197 		return -1;
198 
199 	if (do_read(buf, size) < 0) {
200 		free(buf);
201 		return -1;
202 	}
203 
204 	parse_ftrace_printk(pevent, buf, size);
205 
206 	free(buf);
207 	return 0;
208 }
209 
210 static int read_header_files(struct pevent *pevent)
211 {
212 	unsigned long long size;
213 	char *header_page;
214 	char buf[BUFSIZ];
215 	int ret = 0;
216 
217 	if (do_read(buf, 12) < 0)
218 		return -1;
219 
220 	if (memcmp(buf, "header_page", 12) != 0) {
221 		pr_debug("did not read header page");
222 		return -1;
223 	}
224 
225 	size = read8(pevent);
226 
227 	header_page = malloc(size);
228 	if (header_page == NULL)
229 		return -1;
230 
231 	if (do_read(header_page, size) < 0) {
232 		pr_debug("did not read header page");
233 		free(header_page);
234 		return -1;
235 	}
236 
237 	if (!pevent_parse_header_page(pevent, header_page, size,
238 				      pevent_get_long_size(pevent))) {
239 		/*
240 		 * The commit field in the page is of type long,
241 		 * use that instead, since it represents the kernel.
242 		 */
243 		pevent_set_long_size(pevent, pevent->header_page_size_size);
244 	}
245 	free(header_page);
246 
247 	if (do_read(buf, 13) < 0)
248 		return -1;
249 
250 	if (memcmp(buf, "header_event", 13) != 0) {
251 		pr_debug("did not read header event");
252 		return -1;
253 	}
254 
255 	size = read8(pevent);
256 	skip(size);
257 
258 	return ret;
259 }
260 
261 static int read_ftrace_file(struct pevent *pevent, unsigned long long size)
262 {
263 	char *buf;
264 
265 	buf = malloc(size);
266 	if (buf == NULL)
267 		return -1;
268 
269 	if (do_read(buf, size) < 0) {
270 		free(buf);
271 		return -1;
272 	}
273 
274 	parse_ftrace_file(pevent, buf, size);
275 	free(buf);
276 	return 0;
277 }
278 
279 static int read_event_file(struct pevent *pevent, char *sys,
280 			    unsigned long long size)
281 {
282 	char *buf;
283 
284 	buf = malloc(size);
285 	if (buf == NULL)
286 		return -1;
287 
288 	if (do_read(buf, size) < 0) {
289 		free(buf);
290 		return -1;
291 	}
292 
293 	parse_event_file(pevent, buf, size, sys);
294 	free(buf);
295 	return 0;
296 }
297 
298 static int read_ftrace_files(struct pevent *pevent)
299 {
300 	unsigned long long size;
301 	int count;
302 	int i;
303 	int ret;
304 
305 	count = read4(pevent);
306 
307 	for (i = 0; i < count; i++) {
308 		size = read8(pevent);
309 		ret = read_ftrace_file(pevent, size);
310 		if (ret)
311 			return ret;
312 	}
313 	return 0;
314 }
315 
316 static int read_event_files(struct pevent *pevent)
317 {
318 	unsigned long long size;
319 	char *sys;
320 	int systems;
321 	int count;
322 	int i,x;
323 	int ret;
324 
325 	systems = read4(pevent);
326 
327 	for (i = 0; i < systems; i++) {
328 		sys = read_string();
329 		if (sys == NULL)
330 			return -1;
331 
332 		count = read4(pevent);
333 
334 		for (x=0; x < count; x++) {
335 			size = read8(pevent);
336 			ret = read_event_file(pevent, sys, size);
337 			if (ret)
338 				return ret;
339 		}
340 	}
341 	return 0;
342 }
343 
344 ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
345 {
346 	char buf[BUFSIZ];
347 	char test[] = { 23, 8, 68 };
348 	char *version;
349 	int show_version = 0;
350 	int show_funcs = 0;
351 	int show_printk = 0;
352 	ssize_t size = -1;
353 	int file_bigendian;
354 	int host_bigendian;
355 	int file_long_size;
356 	int file_page_size;
357 	struct pevent *pevent = NULL;
358 	int err;
359 
360 	repipe = __repipe;
361 	input_fd = fd;
362 
363 	if (do_read(buf, 3) < 0)
364 		return -1;
365 	if (memcmp(buf, test, 3) != 0) {
366 		pr_debug("no trace data in the file");
367 		return -1;
368 	}
369 
370 	if (do_read(buf, 7) < 0)
371 		return -1;
372 	if (memcmp(buf, "tracing", 7) != 0) {
373 		pr_debug("not a trace file (missing 'tracing' tag)");
374 		return -1;
375 	}
376 
377 	version = read_string();
378 	if (version == NULL)
379 		return -1;
380 	if (show_version)
381 		printf("version = %s\n", version);
382 	free(version);
383 
384 	if (do_read(buf, 1) < 0)
385 		return -1;
386 	file_bigendian = buf[0];
387 	host_bigendian = bigendian();
388 
389 	if (trace_event__init(tevent)) {
390 		pr_debug("trace_event__init failed");
391 		goto out;
392 	}
393 
394 	pevent = tevent->pevent;
395 
396 	pevent_set_flag(pevent, PEVENT_NSEC_OUTPUT);
397 	pevent_set_file_bigendian(pevent, file_bigendian);
398 	pevent_set_host_bigendian(pevent, host_bigendian);
399 
400 	if (do_read(buf, 1) < 0)
401 		goto out;
402 	file_long_size = buf[0];
403 
404 	file_page_size = read4(pevent);
405 	if (!file_page_size)
406 		goto out;
407 
408 	pevent_set_long_size(pevent, file_long_size);
409 	pevent_set_page_size(pevent, file_page_size);
410 
411 	err = read_header_files(pevent);
412 	if (err)
413 		goto out;
414 	err = read_ftrace_files(pevent);
415 	if (err)
416 		goto out;
417 	err = read_event_files(pevent);
418 	if (err)
419 		goto out;
420 	err = read_proc_kallsyms(pevent);
421 	if (err)
422 		goto out;
423 	err = read_ftrace_printk(pevent);
424 	if (err)
425 		goto out;
426 
427 	size = trace_data_size;
428 	repipe = false;
429 
430 	if (show_funcs) {
431 		pevent_print_funcs(pevent);
432 	} else if (show_printk) {
433 		pevent_print_printk(pevent);
434 	}
435 
436 	pevent = NULL;
437 
438 out:
439 	if (pevent)
440 		trace_event__cleanup(tevent);
441 	return size;
442 }
443