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 	int ret;
264 	char *buf;
265 
266 	buf = malloc(size);
267 	if (buf == NULL) {
268 		pr_debug("memory allocation failure\n");
269 		return -1;
270 	}
271 
272 	ret = do_read(buf, size);
273 	if (ret < 0) {
274 		pr_debug("error reading ftrace file.\n");
275 		goto out;
276 	}
277 
278 	ret = parse_ftrace_file(pevent, buf, size);
279 	if (ret < 0)
280 		pr_debug("error parsing ftrace file.\n");
281 out:
282 	free(buf);
283 	return ret;
284 }
285 
286 static int read_event_file(struct pevent *pevent, char *sys,
287 			    unsigned long long size)
288 {
289 	int ret;
290 	char *buf;
291 
292 	buf = malloc(size);
293 	if (buf == NULL) {
294 		pr_debug("memory allocation failure\n");
295 		return -1;
296 	}
297 
298 	ret = do_read(buf, size);
299 	if (ret < 0) {
300 		free(buf);
301 		goto out;
302 	}
303 
304 	ret = parse_event_file(pevent, buf, size, sys);
305 	if (ret < 0)
306 		pr_debug("error parsing event file.\n");
307 out:
308 	free(buf);
309 	return ret;
310 }
311 
312 static int read_ftrace_files(struct pevent *pevent)
313 {
314 	unsigned long long size;
315 	int count;
316 	int i;
317 	int ret;
318 
319 	count = read4(pevent);
320 
321 	for (i = 0; i < count; i++) {
322 		size = read8(pevent);
323 		ret = read_ftrace_file(pevent, size);
324 		if (ret)
325 			return ret;
326 	}
327 	return 0;
328 }
329 
330 static int read_event_files(struct pevent *pevent)
331 {
332 	unsigned long long size;
333 	char *sys;
334 	int systems;
335 	int count;
336 	int i,x;
337 	int ret;
338 
339 	systems = read4(pevent);
340 
341 	for (i = 0; i < systems; i++) {
342 		sys = read_string();
343 		if (sys == NULL)
344 			return -1;
345 
346 		count = read4(pevent);
347 
348 		for (x=0; x < count; x++) {
349 			size = read8(pevent);
350 			ret = read_event_file(pevent, sys, size);
351 			if (ret)
352 				return ret;
353 		}
354 	}
355 	return 0;
356 }
357 
358 static int read_saved_cmdline(struct pevent *pevent)
359 {
360 	unsigned long long size;
361 	char *buf;
362 	int ret;
363 
364 	/* it can have 0 size */
365 	size = read8(pevent);
366 	if (!size)
367 		return 0;
368 
369 	buf = malloc(size + 1);
370 	if (buf == NULL) {
371 		pr_debug("memory allocation failure\n");
372 		return -1;
373 	}
374 
375 	ret = do_read(buf, size);
376 	if (ret < 0) {
377 		pr_debug("error reading saved cmdlines\n");
378 		goto out;
379 	}
380 
381 	parse_saved_cmdline(pevent, buf, size);
382 	ret = 0;
383 out:
384 	free(buf);
385 	return ret;
386 }
387 
388 ssize_t trace_report(int fd, struct trace_event *tevent, bool __repipe)
389 {
390 	char buf[BUFSIZ];
391 	char test[] = { 23, 8, 68 };
392 	char *version;
393 	int show_version = 0;
394 	int show_funcs = 0;
395 	int show_printk = 0;
396 	ssize_t size = -1;
397 	int file_bigendian;
398 	int host_bigendian;
399 	int file_long_size;
400 	int file_page_size;
401 	struct pevent *pevent = NULL;
402 	int err;
403 
404 	repipe = __repipe;
405 	input_fd = fd;
406 
407 	if (do_read(buf, 3) < 0)
408 		return -1;
409 	if (memcmp(buf, test, 3) != 0) {
410 		pr_debug("no trace data in the file");
411 		return -1;
412 	}
413 
414 	if (do_read(buf, 7) < 0)
415 		return -1;
416 	if (memcmp(buf, "tracing", 7) != 0) {
417 		pr_debug("not a trace file (missing 'tracing' tag)");
418 		return -1;
419 	}
420 
421 	version = read_string();
422 	if (version == NULL)
423 		return -1;
424 	if (show_version)
425 		printf("version = %s\n", version);
426 
427 	if (do_read(buf, 1) < 0) {
428 		free(version);
429 		return -1;
430 	}
431 	file_bigendian = buf[0];
432 	host_bigendian = bigendian();
433 
434 	if (trace_event__init(tevent)) {
435 		pr_debug("trace_event__init failed");
436 		goto out;
437 	}
438 
439 	pevent = tevent->pevent;
440 
441 	pevent_set_flag(pevent, PEVENT_NSEC_OUTPUT);
442 	pevent_set_file_bigendian(pevent, file_bigendian);
443 	pevent_set_host_bigendian(pevent, host_bigendian);
444 
445 	if (do_read(buf, 1) < 0)
446 		goto out;
447 	file_long_size = buf[0];
448 
449 	file_page_size = read4(pevent);
450 	if (!file_page_size)
451 		goto out;
452 
453 	pevent_set_long_size(pevent, file_long_size);
454 	pevent_set_page_size(pevent, file_page_size);
455 
456 	err = read_header_files(pevent);
457 	if (err)
458 		goto out;
459 	err = read_ftrace_files(pevent);
460 	if (err)
461 		goto out;
462 	err = read_event_files(pevent);
463 	if (err)
464 		goto out;
465 	err = read_proc_kallsyms(pevent);
466 	if (err)
467 		goto out;
468 	err = read_ftrace_printk(pevent);
469 	if (err)
470 		goto out;
471 	if (atof(version) >= 0.6) {
472 		err = read_saved_cmdline(pevent);
473 		if (err)
474 			goto out;
475 	}
476 
477 	size = trace_data_size;
478 	repipe = false;
479 
480 	if (show_funcs) {
481 		pevent_print_funcs(pevent);
482 	} else if (show_printk) {
483 		pevent_print_printk(pevent);
484 	}
485 
486 	pevent = NULL;
487 
488 out:
489 	if (pevent)
490 		trace_event__cleanup(tevent);
491 	free(version);
492 	return size;
493 }
494