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[lttng-tools.git] / src / bin / lttng-crash / lttng-crash.c
1 /*
2 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
3 * Copyright (C) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #include <getopt.h>
20 #include <signal.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <sys/stat.h>
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 #include <sys/mman.h>
28 #include <fcntl.h>
29 #include <sys/wait.h>
30 #include <unistd.h>
31 #include <ctype.h>
32 #include <dirent.h>
33 #include <byteswap.h>
34 #include <inttypes.h>
35 #include <stdbool.h>
36
37 #include <version.h>
38 #include <lttng/lttng.h>
39 #include <common/common.h>
40 #include <common/utils.h>
41
42 #define DEFAULT_VIEWER "babeltrace"
43
44 #define COPY_BUFLEN 4096
45 #define RB_CRASH_DUMP_ABI_LEN 32
46
47 #define RB_CRASH_DUMP_ABI_MAGIC_LEN 16
48
49 /*
50 * The 128-bit magic number is xor'd in the process data so it does not
51 * cause a false positive when searching for buffers by scanning memory.
52 * The actual magic number is:
53 * 0x17, 0x7B, 0xF1, 0x77, 0xBF, 0x17, 0x7B, 0xF1,
54 * 0x77, 0xBF, 0x17, 0x7B, 0xF1, 0x77, 0xBF, 0x17,
55 */
56 #define RB_CRASH_DUMP_ABI_MAGIC_XOR \
57 { \
58 0x17 ^ 0xFF, 0x7B ^ 0xFF, 0xF1 ^ 0xFF, 0x77 ^ 0xFF, \
59 0xBF ^ 0xFF, 0x17 ^ 0xFF, 0x7B ^ 0xFF, 0xF1 ^ 0xFF, \
60 0x77 ^ 0xFF, 0xBF ^ 0xFF, 0x17 ^ 0xFF, 0x7B ^ 0xFF, \
61 0xF1 ^ 0xFF, 0x77 ^ 0xFF, 0xBF ^ 0xFF, 0x17 ^ 0xFF, \
62 }
63
64 static const char *help_msg =
65 #ifdef LTTNG_EMBED_HELP
66 #include <lttng-crash.1.h>
67 #else
68 NULL
69 #endif
70 ;
71
72 /*
73 * Non-static to ensure the compiler does not optimize away the xor.
74 */
75 uint8_t lttng_crash_expected_magic_xor[] = RB_CRASH_DUMP_ABI_MAGIC_XOR;
76
77 #define RB_CRASH_ENDIAN 0x1234
78 #define RB_CRASH_ENDIAN_REVERSE 0x3412
79
80 enum lttng_crash_type {
81 LTTNG_CRASH_TYPE_UST = 0,
82 LTTNG_CRASH_TYPE_KERNEL = 1,
83 };
84
85 /* LTTng ring buffer defines (copied) */
86
87 #define HALF_ULONG_BITS(wl) (((wl) * CHAR_BIT) >> 1)
88
89 #define SB_ID_OFFSET_SHIFT(wl) (HALF_ULONG_BITS(wl) + 1)
90 #define SB_ID_OFFSET_COUNT(wl) (1UL << SB_ID_OFFSET_SHIFT(wl))
91 #define SB_ID_OFFSET_MASK(wl) (~(SB_ID_OFFSET_COUNT(wl) - 1))
92 /*
93 * Lowest bit of top word half belongs to noref. Used only for overwrite mode.
94 */
95 #define SB_ID_NOREF_SHIFT(wl) (SB_ID_OFFSET_SHIFT(wl) - 1)
96 #define SB_ID_NOREF_COUNT(wl) (1UL << SB_ID_NOREF_SHIFT(wl))
97 #define SB_ID_NOREF_MASK(wl) SB_ID_NOREF_COUNT(wl)
98 /*
99 * In overwrite mode: lowest half of word is used for index.
100 * Limit of 2^16 subbuffers per buffer on 32-bit, 2^32 on 64-bit.
101 * In producer-consumer mode: whole word used for index.
102 */
103 #define SB_ID_INDEX_SHIFT(wl) 0
104 #define SB_ID_INDEX_COUNT(wl) (1UL << SB_ID_INDEX_SHIFT(wl))
105 #define SB_ID_INDEX_MASK(wl) (SB_ID_NOREF_COUNT(wl) - 1)
106
107 enum rb_modes {
108 RING_BUFFER_OVERWRITE = 0, /* Overwrite when buffer full */
109 RING_BUFFER_DISCARD = 1, /* Discard when buffer full */
110 };
111
112 struct crash_abi_unknown {
113 uint8_t magic[RB_CRASH_DUMP_ABI_MAGIC_LEN];
114 uint64_t mmap_length; /* Overall length of crash record */
115 uint16_t endian; /*
116 * { 0x12, 0x34 }: big endian
117 * { 0x34, 0x12 }: little endian
118 */
119 uint16_t major; /* Major number. */
120 uint16_t minor; /* Minor number. */
121 uint8_t word_size; /* Word size (bytes). */
122 uint8_t layout_type; /* enum lttng_crash_layout */
123 } __attribute__((packed));
124
125 struct crash_abi_0_0 {
126 struct crash_abi_unknown parent;
127
128 struct {
129 uint32_t prod_offset;
130 uint32_t consumed_offset;
131 uint32_t commit_hot_array;
132 uint32_t commit_hot_seq;
133 uint32_t buf_wsb_array;
134 uint32_t buf_wsb_id;
135 uint32_t sb_array;
136 uint32_t sb_array_shmp_offset;
137 uint32_t sb_backend_p_offset;
138 uint32_t content_size;
139 uint32_t packet_size;
140 } __attribute__((packed)) offset;
141 struct {
142 uint8_t prod_offset;
143 uint8_t consumed_offset;
144 uint8_t commit_hot_seq;
145 uint8_t buf_wsb_id;
146 uint8_t sb_array_shmp_offset;
147 uint8_t sb_backend_p_offset;
148 uint8_t content_size;
149 uint8_t packet_size;
150 } __attribute__((packed)) length;
151 struct {
152 uint32_t commit_hot_array;
153 uint32_t buf_wsb_array;
154 uint32_t sb_array;
155 } __attribute__((packed)) stride;
156
157 uint64_t buf_size; /* Size of the buffer */
158 uint64_t subbuf_size; /* Sub-buffer size */
159 uint64_t num_subbuf; /* Number of sub-buffers for writer */
160 uint32_t mode; /* Buffer mode: 0: overwrite, 1: discard */
161 } __attribute__((packed));
162
163 struct lttng_crash_layout {
164 struct {
165 int prod_offset, consumed_offset,
166 commit_hot_array, commit_hot_seq,
167 buf_wsb_array, buf_wsb_id,
168 sb_array, sb_array_shmp_offset,
169 sb_backend_p_offset, content_size,
170 packet_size;
171 } offset;
172 struct {
173 int prod_offset, consumed_offset,
174 commit_hot_seq, buf_wsb_id,
175 sb_array_shmp_offset, sb_backend_p_offset,
176 content_size, packet_size;
177 } length;
178 struct {
179 int commit_hot_array, buf_wsb_array, sb_array;
180 } stride;
181
182 int reverse_byte_order;
183 int word_size;
184
185 uint64_t mmap_length; /* Length of crash record */
186 uint64_t buf_size; /* Size of the buffer */
187 uint64_t subbuf_size; /* Sub-buffer size */
188 uint64_t num_subbuf; /* Number of sub-buffers for writer */
189 uint32_t mode; /* Buffer mode: 0: overwrite, 1: discard */
190 };
191
192 /* Variables */
193 static char *progname,
194 *opt_viewer_path = NULL,
195 *opt_output_path = NULL;
196
197 static char *input_path;
198
199 int lttng_opt_quiet, lttng_opt_verbose, lttng_opt_mi;
200
201 enum {
202 OPT_DUMP_OPTIONS,
203 };
204
205 /* Getopt options. No first level command. */
206 static struct option long_options[] = {
207 { "version", 0, NULL, 'V' },
208 { "help", 0, NULL, 'h' },
209 { "verbose", 0, NULL, 'v' },
210 { "viewer", 1, NULL, 'e' },
211 { "extract", 1, NULL, 'x' },
212 { "list-options", 0, NULL, OPT_DUMP_OPTIONS },
213 { NULL, 0, NULL, 0 },
214 };
215
216 static void usage(void)
217 {
218 int ret = utils_show_help(1, "lttng-crash", help_msg);
219
220 if (ret) {
221 ERR("Cannot show --help for `lttng-crash`");
222 perror("exec");
223 exit(EXIT_FAILURE);
224 }
225 }
226
227 static void version(FILE *ofp)
228 {
229 fprintf(ofp, "%s (LTTng Crash Trace Viewer) " VERSION " - " VERSION_NAME
230 "%s\n",
231 progname,
232 GIT_VERSION[0] == '\0' ? "" : " - " GIT_VERSION);
233 }
234
235 /*
236 * list_options
237 *
238 * List options line by line. This is mostly for bash auto completion and to
239 * avoid difficult parsing.
240 */
241 static void list_options(FILE *ofp)
242 {
243 int i = 0;
244 struct option *option = NULL;
245
246 option = &long_options[i];
247 while (option->name != NULL) {
248 fprintf(ofp, "--%s\n", option->name);
249
250 if (isprint(option->val)) {
251 fprintf(ofp, "-%c\n", option->val);
252 }
253
254 i++;
255 option = &long_options[i];
256 }
257 }
258
259 /*
260 * Parse command line arguments.
261 *
262 * Return 0 if OK, else -1
263 */
264 static int parse_args(int argc, char **argv)
265 {
266 int opt, ret = 0;
267
268 if (argc < 2) {
269 usage();
270 exit(EXIT_FAILURE);
271 }
272
273 while ((opt = getopt_long(argc, argv, "+Vhve:x:", long_options, NULL)) != -1) {
274 switch (opt) {
275 case 'V':
276 version(stdout);
277 ret = 1;
278 goto end;
279 case 'h':
280 usage();
281 ret = 1;
282 goto end;
283 case 'v':
284 /* There is only 3 possible level of verbosity. (-vvv) */
285 if (lttng_opt_verbose < 3) {
286 lttng_opt_verbose += 1;
287 }
288 break;
289 case 'e':
290 free(opt_viewer_path);
291 opt_viewer_path = strdup(optarg);
292 break;
293 case 'x':
294 free(opt_output_path);
295 opt_output_path = strdup(optarg);
296 break;
297 case OPT_DUMP_OPTIONS:
298 list_options(stdout);
299 ret = 1;
300 goto end;
301 default:
302 ERR("Unknown command-line option");
303 goto error;
304 }
305 }
306
307 if (!opt_viewer_path) {
308 opt_viewer_path = DEFAULT_VIEWER;
309 }
310
311 /* No leftovers, or more than one input path, print usage and quit */
312 if (argc - optind != 1) {
313 ERR("Command-line error: Specify exactly one input path");
314 goto error;
315 }
316
317 input_path = argv[optind];
318 end:
319 return ret;
320
321 error:
322 return -1;
323 }
324
325 static
326 int copy_file(const char *file_dest, const char *file_src)
327 {
328 int fd_src = -1, fd_dest = -1;
329 ssize_t readlen, writelen;
330 char buf[COPY_BUFLEN];
331 int ret;
332
333 DBG("Copy metadata file '%s' into '%s'", file_src, file_dest);
334
335 fd_src = open(file_src, O_RDONLY);
336 if (fd_src < 0) {
337 PERROR("Error opening %s for reading", file_src);
338 ret = -errno;
339 goto error;
340 }
341 fd_dest = open(file_dest, O_RDWR | O_CREAT | O_EXCL,
342 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
343 if (fd_dest < 0) {
344 PERROR("Error opening %s for writing", file_dest);
345 ret = -errno;
346 goto error;
347 }
348
349 for (;;) {
350 readlen = lttng_read(fd_src, buf, COPY_BUFLEN);
351 if (readlen < 0) {
352 PERROR("Error reading input file");
353 ret = -1;
354 goto error;
355 }
356 if (!readlen) {
357 break;
358 }
359 writelen = lttng_write(fd_dest, buf, readlen);
360 if (writelen < readlen) {
361 PERROR("Error writing to output file");
362 ret = -1;
363 goto error;
364 }
365 }
366
367 ret = 0;
368 error:
369 if (fd_src >= 0) {
370 if (close(fd_src) < 0) {
371 PERROR("Error closing %s", file_src);
372 }
373 }
374
375 if (fd_dest >= 0) {
376 if (close(fd_dest) < 0) {
377 PERROR("Error closing %s", file_dest);
378 }
379 }
380 return ret;
381 }
382
383 static
384 uint64_t _crash_get_field(const struct lttng_crash_layout *layout,
385 const char *ptr, size_t size)
386 {
387 switch (size) {
388 case 1: return *(uint8_t *) ptr;
389 case 2: if (layout->reverse_byte_order) {
390 return __bswap_16(*(uint16_t *) ptr);
391 } else {
392 return *(uint16_t *) ptr;
393
394 }
395 case 4: if (layout->reverse_byte_order) {
396 return __bswap_32(*(uint32_t *) ptr);
397 } else {
398 return *(uint32_t *) ptr;
399
400 }
401 case 8: if (layout->reverse_byte_order) {
402 return __bswap_64(*(uint64_t *) ptr);
403 } else {
404 return *(uint64_t *) ptr;
405 }
406 default:
407 abort();
408 return -1;
409 }
410
411 }
412
413 #define crash_get_field(layout, map, name) \
414 _crash_get_field(layout, (map) + (layout)->offset.name, \
415 layout->length.name)
416
417 #define crash_get_array_field(layout, map, array_name, idx, field_name) \
418 _crash_get_field(layout, \
419 (map) + (layout)->offset.array_name \
420 + (idx * (layout)->stride.array_name) \
421 + (layout)->offset.field_name, \
422 (layout)->length.field_name)
423
424 #define crash_get_hdr_raw_field(layout, hdr, name) ((hdr)->name)
425
426 #define crash_get_hdr_field(layout, hdr, name) \
427 _crash_get_field(layout, (const char *) &(hdr)->name, \
428 sizeof((hdr)->name))
429
430 #define crash_get_layout(layout, hdr, name) \
431 do { \
432 (layout)->name = crash_get_hdr_field(layout, hdr, \
433 name); \
434 DBG("layout.%s = %" PRIu64, #name, \
435 (uint64_t) (layout)->name); \
436 } while (0)
437
438 static
439 int get_crash_layout_0_0(struct lttng_crash_layout *layout,
440 char *map)
441 {
442 const struct crash_abi_0_0 *abi = (const struct crash_abi_0_0 *) map;
443
444 crash_get_layout(layout, abi, offset.prod_offset);
445 crash_get_layout(layout, abi, offset.consumed_offset);
446 crash_get_layout(layout, abi, offset.commit_hot_array);
447 crash_get_layout(layout, abi, offset.commit_hot_seq);
448 crash_get_layout(layout, abi, offset.buf_wsb_array);
449 crash_get_layout(layout, abi, offset.buf_wsb_id);
450 crash_get_layout(layout, abi, offset.sb_array);
451 crash_get_layout(layout, abi, offset.sb_array_shmp_offset);
452 crash_get_layout(layout, abi, offset.sb_backend_p_offset);
453 crash_get_layout(layout, abi, offset.content_size);
454 crash_get_layout(layout, abi, offset.packet_size);
455
456 crash_get_layout(layout, abi, length.prod_offset);
457 crash_get_layout(layout, abi, length.consumed_offset);
458 crash_get_layout(layout, abi, length.commit_hot_seq);
459 crash_get_layout(layout, abi, length.buf_wsb_id);
460 crash_get_layout(layout, abi, length.sb_array_shmp_offset);
461 crash_get_layout(layout, abi, length.sb_backend_p_offset);
462 crash_get_layout(layout, abi, length.content_size);
463 crash_get_layout(layout, abi, length.packet_size);
464
465 crash_get_layout(layout, abi, stride.commit_hot_array);
466 crash_get_layout(layout, abi, stride.buf_wsb_array);
467 crash_get_layout(layout, abi, stride.sb_array);
468
469 crash_get_layout(layout, abi, buf_size);
470 crash_get_layout(layout, abi, subbuf_size);
471 crash_get_layout(layout, abi, num_subbuf);
472 crash_get_layout(layout, abi, mode);
473
474 return 0;
475 }
476
477 static
478 void print_dbg_magic(const uint8_t *magic)
479 {
480 DBG("magic: 0x%X%X%X%X%X%X%X%X%X%X%X%X%X%X%X%X",
481 magic[0], magic[1], magic[2], magic[3],
482 magic[4], magic[5], magic[6], magic[7],
483 magic[8], magic[9], magic[10], magic[11],
484 magic[12], magic[13], magic[14], magic[15]);
485 }
486
487 static
488 int check_magic(const uint8_t *magic)
489 {
490 int i;
491
492 for (i = 0; i < RB_CRASH_DUMP_ABI_MAGIC_LEN; i++) {
493 if ((magic[i] ^ 0xFF) != lttng_crash_expected_magic_xor[i]) {
494 return -1;
495 }
496 }
497 return 0;
498 }
499
500 static
501 int get_crash_layout(struct lttng_crash_layout *layout, int fd,
502 const char *input_file)
503 {
504 char *map;
505 int ret = 0, unmapret;
506 const uint8_t *magic;
507 uint64_t mmap_length;
508 uint16_t major, minor;
509 uint8_t word_size;
510 const struct crash_abi_unknown *abi;
511 uint16_t endian;
512 enum lttng_crash_type layout_type;
513 struct stat stat;
514
515 ret = fstat(fd, &stat);
516 if (ret < 0) {
517 PERROR("Failed to fstat '%s'", input_file);
518 return -1;
519 }
520 if (stat.st_size < RB_CRASH_DUMP_ABI_LEN) {
521 ERR("File '%s' truncated: file length of %" PRIi64
522 " bytes does not meet the minimal expected "
523 "length of %d bytes",
524 input_file, (int64_t) stat.st_size,
525 RB_CRASH_DUMP_ABI_LEN);
526 return -1;
527 }
528 map = mmap(NULL, RB_CRASH_DUMP_ABI_LEN, PROT_READ, MAP_PRIVATE,
529 fd, 0);
530 if (map == MAP_FAILED) {
531 PERROR("Mapping file");
532 return -1;
533 }
534 abi = (const struct crash_abi_unknown *) map;
535 magic = crash_get_hdr_raw_field(layout, abi, magic);
536 print_dbg_magic(magic);
537 if (check_magic(magic)) {
538 DBG("Unknown magic number");
539 ret = 1; /* positive return value, skip */
540 goto end;
541 }
542 endian = crash_get_hdr_field(layout, abi, endian);
543 switch (endian) {
544 case RB_CRASH_ENDIAN:
545 break;
546 case RB_CRASH_ENDIAN_REVERSE:
547 layout->reverse_byte_order = 1;
548 break;
549 default:
550 DBG("Unknown endianness value: 0x%X", (unsigned int) endian);
551 ret = 1; /* positive return value, skip */
552 goto end;
553 }
554 layout_type = (enum lttng_crash_type) crash_get_hdr_field(layout, abi, layout_type);
555 switch (layout_type) {
556 case LTTNG_CRASH_TYPE_UST:
557 break;
558 case LTTNG_CRASH_TYPE_KERNEL:
559 ERR("lttng-modules buffer layout support not implemented");
560 ret = 1; /* positive return value, skip */
561 goto end;
562 default:
563 ERR("Unknown layout type %u", (unsigned int) layout_type);
564 ret = 1; /* positive return value, skip */
565 goto end;
566 }
567 mmap_length = crash_get_hdr_field(layout, abi, mmap_length);
568 DBG("mmap_length: %" PRIu64, mmap_length);
569 layout->mmap_length = mmap_length;
570 major = crash_get_hdr_field(layout, abi, major);
571 DBG("major: %u", major);
572 minor = crash_get_hdr_field(layout, abi, minor);
573 DBG("minor: %u", minor);
574 word_size = crash_get_hdr_field(layout, abi, word_size);
575 DBG("word_size: %u", word_size);
576 switch (major) {
577 case 0:
578 switch (minor) {
579 case 0:
580 ret = get_crash_layout_0_0(layout, map);
581 if (ret)
582 goto end;
583 break;
584 default:
585 ret = -1;
586 ERR("Unsupported crash ABI %u.%u\n", major, minor);
587 goto end;
588 }
589 break;
590 default:
591 ERR("Unsupported crash ABI %u.%u\n", major, minor);
592 ret = -1;
593 goto end;
594 }
595 layout->word_size = word_size;
596 end:
597 unmapret = munmap(map, RB_CRASH_DUMP_ABI_LEN);
598 if (unmapret) {
599 PERROR("munmap");
600 }
601 return ret;
602 }
603
604 /* buf_trunc mask selects only the buffer number. */
605 static inline
606 uint64_t buf_trunc(uint64_t offset, uint64_t buf_size)
607 {
608 return offset & ~(buf_size - 1);
609 }
610
611 /* subbuf_trunc mask selects the subbuffer number. */
612 static inline
613 uint64_t subbuf_trunc(uint64_t offset, uint64_t subbuf_size)
614 {
615 return offset & ~(subbuf_size - 1);
616 }
617
618 /* buf_offset mask selects only the offset within the current buffer. */
619 static inline
620 uint64_t buf_offset(uint64_t offset, uint64_t buf_size)
621 {
622 return offset & (buf_size - 1);
623 }
624
625 /* subbuf_offset mask selects the offset within the current subbuffer. */
626 static inline
627 uint64_t subbuf_offset(uint64_t offset, uint64_t subbuf_size)
628 {
629 return offset & (subbuf_size - 1);
630 }
631
632 /* subbuf_index returns the index of the current subbuffer within the buffer. */
633 static inline
634 uint64_t subbuf_index(uint64_t offset, uint64_t buf_size, uint64_t subbuf_size)
635 {
636 return buf_offset(offset, buf_size) / subbuf_size;
637 }
638
639 static inline
640 uint64_t subbuffer_id_get_index(uint32_t mode, uint64_t id,
641 unsigned int wl)
642 {
643 if (mode == RING_BUFFER_OVERWRITE)
644 return id & SB_ID_INDEX_MASK(wl);
645 else
646 return id;
647 }
648
649 static
650 int copy_crash_subbuf(const struct lttng_crash_layout *layout,
651 int fd_dest, char *buf, uint64_t offset)
652 {
653 uint64_t buf_size, subbuf_size, num_subbuf, sbidx, id,
654 sb_bindex, rpages_offset, p_offset, seq_cc,
655 committed, commit_count_mask, consumed_cur,
656 packet_size;
657 char *subbuf_ptr;
658 ssize_t writelen;
659
660 /*
661 * Get the current subbuffer by applying the proper mask to
662 * "offset", and looking up the subbuf location within the
663 * source file buf.
664 */
665
666 buf_size = layout->buf_size;
667 subbuf_size = layout->subbuf_size;
668 num_subbuf = layout->num_subbuf;
669
670 switch (layout->word_size) {
671 case 4: commit_count_mask = 0xFFFFFFFFULL / num_subbuf;
672 break;
673 case 8: commit_count_mask = 0xFFFFFFFFFFFFFFFFULL / num_subbuf;
674 break;
675 default:
676 ERR("Unsupported word size: %u",
677 (unsigned int) layout->word_size);
678 return -EINVAL;
679 }
680
681 DBG("Copy crash subbuffer at offset %" PRIu64, offset);
682 sbidx = subbuf_index(offset, buf_size, subbuf_size);
683
684 /*
685 * Find where the seq cc is located. Compute length of data to
686 * copy.
687 */
688 seq_cc = crash_get_array_field(layout, buf, commit_hot_array,
689 sbidx, commit_hot_seq);
690 consumed_cur = crash_get_field(layout, buf, consumed_offset);
691
692 /*
693 * Check that the buffer we are getting is after or at
694 * consumed_cur position.
695 */
696 if ((long) subbuf_trunc(offset, subbuf_size)
697 - (long) subbuf_trunc(consumed_cur, subbuf_size) < 0) {
698 DBG("No data: position is before consumed_cur");
699 goto nodata;
700 }
701
702 /*
703 * Check if subbuffer has been fully committed.
704 */
705 if (((seq_cc - subbuf_size) & commit_count_mask)
706 - (buf_trunc(offset, buf_size) / num_subbuf)
707 == 0) {
708 committed = subbuf_size;
709 } else {
710 committed = subbuf_offset(seq_cc, subbuf_size);
711 if (!committed) {
712 DBG("No data committed, seq_cc: %" PRIu64, seq_cc);
713 goto nodata;
714 }
715 }
716
717 /* Find actual physical offset in subbuffer table */
718 id = crash_get_array_field(layout, buf, buf_wsb_array,
719 sbidx, buf_wsb_id);
720 sb_bindex = subbuffer_id_get_index(layout->mode, id,
721 layout->word_size);
722 rpages_offset = crash_get_array_field(layout, buf, sb_array,
723 sb_bindex, sb_array_shmp_offset);
724 p_offset = crash_get_field(layout, buf + rpages_offset,
725 sb_backend_p_offset);
726 subbuf_ptr = buf + p_offset;
727
728 if (committed == subbuf_size) {
729 /*
730 * Packet header can be used.
731 */
732 if (layout->length.packet_size) {
733 memcpy(&packet_size,
734 subbuf_ptr + layout->offset.packet_size,
735 layout->length.packet_size);
736 if (layout->reverse_byte_order) {
737 packet_size = __bswap_64(packet_size);
738 }
739 packet_size /= CHAR_BIT;
740 } else {
741 packet_size = subbuf_size;
742 }
743 } else {
744 uint64_t patch_size;
745
746 /*
747 * Find where to patch the sub-buffer header with actual
748 * readable data len and packet len, derived from seq
749 * cc. Patch it in our in-memory copy.
750 */
751 patch_size = committed * CHAR_BIT;
752 if (layout->reverse_byte_order) {
753 patch_size = __bswap_64(patch_size);
754 }
755 if (layout->length.content_size) {
756 memcpy(subbuf_ptr + layout->offset.content_size,
757 &patch_size, layout->length.content_size);
758 }
759 if (layout->length.packet_size) {
760 memcpy(subbuf_ptr + layout->offset.packet_size,
761 &patch_size, layout->length.packet_size);
762 }
763 packet_size = committed;
764 }
765
766 /*
767 * Copy packet into fd_dest.
768 */
769 writelen = lttng_write(fd_dest, subbuf_ptr, packet_size);
770 if (writelen < packet_size) {
771 PERROR("Error writing to output file");
772 return -1;
773 }
774 DBG("Copied %" PRIu64 " bytes of data", packet_size);
775 return 0;
776
777 nodata:
778 return -ENODATA;
779 }
780
781 static
782 int copy_crash_data(const struct lttng_crash_layout *layout, int fd_dest,
783 int fd_src)
784 {
785 char *buf;
786 int ret = 0, has_data = 0;
787 struct stat statbuf;
788 size_t src_file_len;
789 uint64_t prod_offset, consumed_offset;
790 uint64_t offset, subbuf_size;
791 ssize_t readlen;
792
793 ret = fstat(fd_src, &statbuf);
794 if (ret) {
795 return ret;
796 }
797 src_file_len = layout->mmap_length;
798 buf = zmalloc(src_file_len);
799 if (!buf) {
800 return -1;
801 }
802 readlen = lttng_read(fd_src, buf, src_file_len);
803 if (readlen < 0) {
804 PERROR("Error reading input file");
805 ret = -1;
806 goto end;
807 }
808
809 prod_offset = crash_get_field(layout, buf, prod_offset);
810 DBG("prod_offset: 0x%" PRIx64, prod_offset);
811 consumed_offset = crash_get_field(layout, buf, consumed_offset);
812 DBG("consumed_offset: 0x%" PRIx64, consumed_offset);
813 subbuf_size = layout->subbuf_size;
814
815 for (offset = consumed_offset; offset < prod_offset;
816 offset += subbuf_size) {
817 ret = copy_crash_subbuf(layout, fd_dest, buf, offset);
818 if (!ret) {
819 has_data = 1;
820 }
821 if (ret) {
822 goto end;
823 }
824 }
825 end:
826 free(buf);
827 if (ret && ret != -ENODATA) {
828 return ret;
829 }
830 if (has_data) {
831 return 0;
832 } else {
833 return -ENODATA;
834 }
835 }
836
837 static
838 int extract_file(int output_dir_fd, const char *output_file,
839 int input_dir_fd, const char *input_file)
840 {
841 int fd_dest, fd_src, ret = 0, closeret;
842 struct lttng_crash_layout layout;
843
844 layout.reverse_byte_order = 0; /* For reading magic number */
845
846 DBG("Extract file '%s'", input_file);
847 fd_src = openat(input_dir_fd, input_file, O_RDONLY);
848 if (fd_src < 0) {
849 PERROR("Error opening '%s' for reading",
850 input_file);
851 ret = -1;
852 goto end;
853 }
854
855 /* Query the crash ABI layout */
856 ret = get_crash_layout(&layout, fd_src, input_file);
857 if (ret) {
858 goto close_src;
859 }
860
861 fd_dest = openat(output_dir_fd, output_file,
862 O_RDWR | O_CREAT | O_EXCL,
863 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
864 if (fd_dest < 0) {
865 PERROR("Error opening '%s' for writing",
866 output_file);
867 ret = -1;
868 goto close_src;
869 }
870
871 ret = copy_crash_data(&layout, fd_dest, fd_src);
872 if (ret) {
873 goto close_dest;
874 }
875
876 close_dest:
877 closeret = close(fd_dest);
878 if (closeret) {
879 PERROR("close");
880 }
881 if (ret == -ENODATA) {
882 closeret = unlinkat(output_dir_fd, output_file, 0);
883 if (closeret) {
884 PERROR("unlinkat");
885 }
886 }
887 close_src:
888 closeret = close(fd_src);
889 if (closeret) {
890 PERROR("close");
891 }
892 end:
893 return ret;
894 }
895
896 static
897 int extract_all_files(const char *output_path,
898 const char *input_path)
899 {
900 DIR *input_dir, *output_dir;
901 int input_dir_fd, output_dir_fd, ret = 0, closeret;
902 struct dirent *entry; /* input */
903
904 /* Open input directory */
905 input_dir = opendir(input_path);
906 if (!input_dir) {
907 PERROR("Cannot open '%s' path", input_path);
908 return -1;
909 }
910 input_dir_fd = dirfd(input_dir);
911 if (input_dir_fd < 0) {
912 PERROR("dirfd");
913 return -1;
914 }
915
916 /* Open output directory */
917 output_dir = opendir(output_path);
918 if (!output_dir) {
919 PERROR("Cannot open '%s' path", output_path);
920 return -1;
921 }
922 output_dir_fd = dirfd(output_dir);
923 if (output_dir_fd < 0) {
924 PERROR("dirfd");
925 return -1;
926 }
927
928 while ((entry = readdir(input_dir))) {
929 if (!strcmp(entry->d_name, ".")
930 || !strcmp(entry->d_name, ".."))
931 continue;
932 ret = extract_file(output_dir_fd, entry->d_name,
933 input_dir_fd, entry->d_name);
934 if (ret == -ENODATA) {
935 DBG("No data in file '%s', skipping", entry->d_name);
936 ret = 0;
937 continue;
938 } else if (ret < 0) {
939 break;
940 } else if (ret > 0) {
941 DBG("Skipping file '%s'", entry->d_name);
942 ret = 0;
943 continue;
944 }
945 }
946 closeret = closedir(output_dir);
947 if (closeret) {
948 PERROR("closedir");
949 }
950 closeret = closedir(input_dir);
951 if (closeret) {
952 PERROR("closedir");
953 }
954 return ret;
955 }
956
957 static
958 int extract_one_trace(const char *output_path,
959 const char *input_path)
960 {
961 char dest[PATH_MAX], src[PATH_MAX];
962 int ret;
963
964 DBG("Extract crash trace '%s' into '%s'", input_path, output_path);
965
966 /* Copy metadata */
967 strncpy(dest, output_path, PATH_MAX);
968 dest[PATH_MAX - 1] = '\0';
969 strncat(dest, "/metadata", PATH_MAX - strlen(dest) - 1);
970
971 strncpy(src, input_path, PATH_MAX);
972 src[PATH_MAX - 1] = '\0';
973 strncat(src, "/metadata", PATH_MAX - strlen(dest) - 1);
974
975 ret = copy_file(dest, src);
976 if (ret) {
977 return ret;
978 }
979
980 /* Extract each other file that has expected header */
981 return extract_all_files(output_path, input_path);
982 }
983
984 static
985 int extract_trace_recursive(const char *output_path,
986 const char *input_path)
987 {
988 DIR *dir;
989 int dir_fd, ret = 0, closeret;
990 struct dirent *entry;
991 size_t path_len;
992 int has_warning = 0;
993
994 /* Open directory */
995 dir = opendir(input_path);
996 if (!dir) {
997 PERROR("Cannot open '%s' path", input_path);
998 return -1;
999 }
1000
1001 path_len = strlen(input_path);
1002
1003 dir_fd = dirfd(dir);
1004 if (dir_fd < 0) {
1005 PERROR("dirfd");
1006 return -1;
1007 }
1008
1009 while ((entry = readdir(dir))) {
1010 struct stat st;
1011 size_t name_len;
1012 char filename[PATH_MAX];
1013
1014 if (!strcmp(entry->d_name, ".")
1015 || !strcmp(entry->d_name, "..")) {
1016 continue;
1017 }
1018
1019 name_len = strlen(entry->d_name);
1020 if (path_len + name_len + 2 > sizeof(filename)) {
1021 ERR("Failed to remove file: path name too long (%s/%s)",
1022 input_path, entry->d_name);
1023 continue;
1024 }
1025
1026 if (snprintf(filename, sizeof(filename), "%s/%s",
1027 input_path, entry->d_name) < 0) {
1028 ERR("Failed to format path.");
1029 continue;
1030 }
1031
1032 if (stat(filename, &st)) {
1033 PERROR("stat");
1034 continue;
1035 }
1036
1037 if (S_ISDIR(st.st_mode)) {
1038 char output_subpath[PATH_MAX];
1039 char input_subpath[PATH_MAX];
1040
1041 strncpy(output_subpath, output_path,
1042 sizeof(output_subpath));
1043 output_subpath[sizeof(output_subpath) - 1] = '\0';
1044 strncat(output_subpath, "/",
1045 sizeof(output_subpath) - strlen(output_subpath) - 1);
1046 strncat(output_subpath, entry->d_name,
1047 sizeof(output_subpath) - strlen(output_subpath) - 1);
1048
1049 ret = mkdir(output_subpath, S_IRWXU | S_IRWXG);
1050 if (ret) {
1051 PERROR("mkdir");
1052 has_warning = 1;
1053 goto end;
1054 }
1055
1056 strncpy(input_subpath, input_path,
1057 sizeof(input_subpath));
1058 input_subpath[sizeof(input_subpath) - 1] = '\0';
1059 strncat(input_subpath, "/",
1060 sizeof(input_subpath) - strlen(input_subpath) - 1);
1061 strncat(input_subpath, entry->d_name,
1062 sizeof(input_subpath) - strlen(input_subpath) - 1);
1063
1064 ret = extract_trace_recursive(output_subpath,
1065 input_subpath);
1066 if (ret) {
1067 has_warning = 1;
1068 }
1069 } else if (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)) {
1070 if (!strcmp(entry->d_name, "metadata")) {
1071 ret = extract_one_trace(output_path,
1072 input_path);
1073 if (ret) {
1074 WARN("Error extracting trace '%s', continuing anyway.",
1075 input_path);
1076 has_warning = 1;
1077 }
1078 }
1079 } else {
1080 has_warning = 1;
1081 goto end;
1082 }
1083 }
1084 end:
1085 closeret = closedir(dir);
1086 if (closeret) {
1087 PERROR("closedir");
1088 }
1089 return has_warning;
1090 }
1091
1092 static
1093 int delete_dir_recursive(const char *path)
1094 {
1095 DIR *dir;
1096 int dir_fd, ret = 0, closeret;
1097 size_t path_len;
1098 struct dirent *entry;
1099
1100 /* Open trace directory */
1101 dir = opendir(path);
1102 if (!dir) {
1103 PERROR("Cannot open '%s' path", path);
1104 ret = -errno;
1105 goto end_no_closedir;
1106 }
1107
1108 path_len = strlen(path);
1109
1110 dir_fd = dirfd(dir);
1111 if (dir_fd < 0) {
1112 PERROR("dirfd");
1113 ret = -errno;
1114 goto end;
1115 }
1116
1117 while ((entry = readdir(dir))) {
1118 struct stat st;
1119 size_t name_len;
1120 char filename[PATH_MAX];
1121
1122 if (!strcmp(entry->d_name, ".")
1123 || !strcmp(entry->d_name, "..")) {
1124 continue;
1125 }
1126
1127 name_len = strlen(entry->d_name);
1128 if (path_len + name_len + 2 > sizeof(filename)) {
1129 ERR("Failed to remove file: path name too long (%s/%s)",
1130 path, entry->d_name);
1131 continue;
1132 }
1133
1134 if (snprintf(filename, sizeof(filename), "%s/%s",
1135 path, entry->d_name) < 0) {
1136 ERR("Failed to format path.");
1137 continue;
1138 }
1139
1140 if (stat(filename, &st)) {
1141 PERROR("stat");
1142 continue;
1143 }
1144
1145 if (S_ISDIR(st.st_mode)) {
1146 char *subpath = zmalloc(PATH_MAX);
1147
1148 if (!subpath) {
1149 PERROR("zmalloc path");
1150 ret = -1;
1151 goto end;
1152 }
1153 strncpy(subpath, path, PATH_MAX);
1154 subpath[PATH_MAX - 1] = '\0';
1155 strncat(subpath, "/",
1156 PATH_MAX - strlen(subpath) - 1);
1157 strncat(subpath, entry->d_name,
1158 PATH_MAX - strlen(subpath) - 1);
1159
1160 ret = delete_dir_recursive(subpath);
1161 free(subpath);
1162 if (ret) {
1163 /* Error occurred, abort traversal. */
1164 goto end;
1165 }
1166 } else if (S_ISREG(st.st_mode)) {
1167 ret = unlinkat(dir_fd, entry->d_name, 0);
1168 if (ret) {
1169 PERROR("Unlinking '%s'", entry->d_name);
1170 goto end;
1171 }
1172 } else {
1173 ret = -EINVAL;
1174 goto end;
1175 }
1176 }
1177 end:
1178 if (!ret) {
1179 ret = rmdir(path);
1180 if (ret) {
1181 PERROR("rmdir '%s'", path);
1182 }
1183 }
1184 closeret = closedir(dir);
1185 if (closeret) {
1186 PERROR("closedir");
1187 }
1188 end_no_closedir:
1189 return ret;
1190 }
1191
1192 static
1193 int view_trace(const char *viewer_path, const char *trace_path)
1194 {
1195 pid_t pid;
1196
1197 pid = fork();
1198 if (pid < 0) {
1199 /* Error */
1200 PERROR("fork");
1201 return -1;
1202 } else if (pid > 0) {
1203 /* Parent */
1204 int status;
1205
1206 pid = waitpid(pid, &status, 0);
1207 if (pid < 0 || !WIFEXITED(status)) {
1208 return -1;
1209 }
1210 } else {
1211 /* Child */
1212 int ret;
1213
1214 ret = execlp(viewer_path, viewer_path,
1215 trace_path, (char *) NULL);
1216 if (ret) {
1217 PERROR("execlp");
1218 exit(EXIT_FAILURE);
1219 }
1220 exit(EXIT_SUCCESS); /* Never reached */
1221 }
1222 return 0;
1223 }
1224
1225 /*
1226 * main
1227 */
1228 int main(int argc, char *argv[])
1229 {
1230 int ret;
1231 bool has_warning = false;
1232 const char *output_path = NULL;
1233 char tmppath[] = "/tmp/lttng-crash-XXXXXX";
1234
1235 progname = argv[0] ? argv[0] : "lttng-crash";
1236
1237 ret = parse_args(argc, argv);
1238 if (ret > 0) {
1239 goto end;
1240 } else if (ret < 0) {
1241 has_warning = true;
1242 goto end;
1243 }
1244
1245 if (opt_output_path) {
1246 output_path = opt_output_path;
1247 ret = mkdir(output_path, S_IRWXU | S_IRWXG);
1248 if (ret) {
1249 PERROR("mkdir");
1250 has_warning = true;
1251 goto end;
1252 }
1253 } else {
1254 output_path = mkdtemp(tmppath);
1255 if (!output_path) {
1256 PERROR("mkdtemp");
1257 has_warning = true;
1258 goto end;
1259 }
1260 }
1261
1262 ret = extract_trace_recursive(output_path, input_path);
1263 if (ret < 0) {
1264 has_warning = true;
1265 goto end;
1266 } else if (ret > 0) {
1267 /* extract_trace_recursive reported a warning. */
1268 has_warning = true;
1269 }
1270 if (!opt_output_path) {
1271 /* View trace */
1272 ret = view_trace(opt_viewer_path, output_path);
1273 if (ret) {
1274 has_warning = true;
1275 }
1276 /* unlink temporary trace */
1277 ret = delete_dir_recursive(output_path);
1278 if (ret) {
1279 has_warning = true;
1280 }
1281 }
1282 end:
1283 exit(has_warning ? EXIT_FAILURE : EXIT_SUCCESS);
1284 }
LTTng 2.0 tools and control repository
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