bootstrap: Standardize on autoreconf -vi
[babeltrace.git] / lib / bin-info.c
CommitLineData
b5a8598f 1/*
dae52e76 2 * bin-info.c
b5a8598f
AB
3 *
4 * Babeltrace - Executable and Shared Object Debug Info Reader
5 *
6 * Copyright 2015 Antoine Busque <abusque@efficios.com>
7 *
8 * Author: Antoine Busque <abusque@efficios.com>
9 *
10 * Permission is hereby granted, free of charge, to any person obtaining a copy
11 * of this software and associated documentation files (the "Software"), to deal
12 * in the Software without restriction, including without limitation the rights
13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14 * copies of the Software, and to permit persons to whom the Software is
15 * furnished to do so, subject to the following conditions:
16 *
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
19 *
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
23 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
26 * SOFTWARE.
27 */
28
29#include <fcntl.h>
30#include <math.h>
31#include <libgen.h>
32#include <stdio.h>
33#include <inttypes.h>
34#include <stdlib.h>
35#include <string.h>
36#include <unistd.h>
37#include <dwarf.h>
38#include <glib.h>
39#include <babeltrace/dwarf.h>
dae52e76 40#include <babeltrace/bin-info.h>
b5a8598f
AB
41#include <babeltrace/crc32.h>
42#include <babeltrace/babeltrace-internal.h>
beef86dc 43#include <babeltrace/utils.h>
b5a8598f
AB
44
45/*
46 * An address printed in hex is at most 20 bytes (16 for 64-bits +
47 * leading 0x + optional leading '+' if addr is an offset + null
48 * character).
49 */
50#define ADDR_STR_LEN 20
51
52BT_HIDDEN
dae52e76 53int bin_info_init(void)
b5a8598f
AB
54{
55 int ret = 0;
56
57 if (elf_version(EV_CURRENT) == EV_NONE) {
1036949d
AB
58 printf_debug("ELF library initialization failed: %s\n",
59 elf_errmsg(-1));
b5a8598f
AB
60 ret = -1;
61 }
62
63 return ret;
64}
65
66BT_HIDDEN
dae52e76 67struct bin_info *bin_info_create(const char *path, uint64_t low_addr,
1a4a1345 68 uint64_t memsz, bool is_pic)
b5a8598f 69{
dae52e76 70 struct bin_info *bin = NULL;
b5a8598f
AB
71
72 if (!path) {
73 goto error;
74 }
75
dae52e76
AB
76 bin = g_new0(struct bin_info, 1);
77 if (!bin) {
b5a8598f
AB
78 goto error;
79 }
80
b7b61ced 81 if (opt_debug_info_target_prefix) {
dae52e76 82 bin->elf_path = g_build_path("/", opt_debug_info_target_prefix,
b7b61ced
AB
83 path, NULL);
84 } else {
dae52e76 85 bin->elf_path = strdup(path);
b7b61ced
AB
86 }
87
dae52e76 88 if (!bin->elf_path) {
b5a8598f
AB
89 goto error;
90 }
91
dae52e76
AB
92 bin->is_pic = is_pic;
93 bin->memsz = memsz;
94 bin->low_addr = low_addr;
95 bin->high_addr = bin->low_addr + bin->memsz;
b5a8598f 96
dae52e76 97 return bin;
b5a8598f
AB
98
99error:
dae52e76 100 bin_info_destroy(bin);
b5a8598f
AB
101 return NULL;
102}
103
104BT_HIDDEN
dae52e76 105void bin_info_destroy(struct bin_info *bin)
b5a8598f 106{
dae52e76 107 if (!bin) {
b5a8598f
AB
108 return;
109 }
110
dae52e76 111 dwarf_end(bin->dwarf_info);
b5a8598f 112
dae52e76
AB
113 free(bin->elf_path);
114 free(bin->dwarf_path);
115 free(bin->build_id);
116 free(bin->dbg_link_filename);
b5a8598f 117
dae52e76 118 elf_end(bin->elf_file);
b5a8598f 119
dae52e76
AB
120 close(bin->elf_fd);
121 close(bin->dwarf_fd);
b5a8598f 122
dae52e76 123 g_free(bin);
b5a8598f
AB
124}
125
b8652b58 126
b5a8598f 127BT_HIDDEN
dae52e76 128int bin_info_set_build_id(struct bin_info *bin, uint8_t *build_id,
b5a8598f
AB
129 size_t build_id_len)
130{
dae52e76 131 if (!bin || !build_id) {
b5a8598f
AB
132 goto error;
133 }
134
dae52e76
AB
135 bin->build_id = malloc(build_id_len);
136 if (!bin->build_id) {
b5a8598f
AB
137 goto error;
138 }
139
dae52e76
AB
140 memcpy(bin->build_id, build_id, build_id_len);
141 bin->build_id_len = build_id_len;
b5a8598f
AB
142
143 /*
144 * Reset the is_elf_only flag in case it had been set
145 * previously, because we might find separate debug info using
146 * the new build id information.
147 */
dae52e76 148 bin->is_elf_only = false;
b5a8598f
AB
149
150 return 0;
151
152error:
153
154 return -1;
155}
156
157BT_HIDDEN
dae52e76 158int bin_info_set_debug_link(struct bin_info *bin, char *filename, uint32_t crc)
b5a8598f 159{
dae52e76 160 if (!bin || !filename) {
b5a8598f
AB
161 goto error;
162 }
163
dae52e76
AB
164 bin->dbg_link_filename = strdup(filename);
165 if (!bin->dbg_link_filename) {
b5a8598f
AB
166 goto error;
167 }
168
dae52e76 169 bin->dbg_link_crc = crc;
b5a8598f
AB
170
171 /*
172 * Reset the is_elf_only flag in case it had been set
173 * previously, because we might find separate debug info using
174 * the new build id information.
175 */
dae52e76 176 bin->is_elf_only = false;
b5a8598f
AB
177
178 return 0;
179
180error:
181
182 return -1;
183}
184
185/**
186 * Tries to read DWARF info from the location given by path, and
dae52e76 187 * attach it to the given bin_info instance if it exists.
b5a8598f 188 *
dae52e76 189 * @param bin bin_info instance for which to set DWARF info
b5a8598f
AB
190 * @param path Presumed location of the DWARF info
191 * @returns 0 on success, -1 on failure
192 */
193static
dae52e76 194int bin_info_set_dwarf_info_from_path(struct bin_info *bin, char *path)
b5a8598f
AB
195{
196 int fd = -1, ret = 0;
197 struct bt_dwarf_cu *cu = NULL;
198 Dwarf *dwarf_info = NULL;
199
dae52e76 200 if (!bin || !path) {
b5a8598f
AB
201 goto error;
202 }
203
204 fd = open(path, O_RDONLY);
205 if (fd < 0) {
206 goto error;
207 }
208
209 dwarf_info = dwarf_begin(fd, DWARF_C_READ);
210 if (!dwarf_info) {
211 goto error;
212 }
213
214 /*
dae52e76
AB
215 * Check if the dwarf info has any CU. If not, the
216 * executable's object file contains no DWARF info.
b5a8598f
AB
217 */
218 cu = bt_dwarf_cu_create(dwarf_info);
219 if (!cu) {
220 goto error;
221 }
222
223 ret = bt_dwarf_cu_next(cu);
224 if (ret) {
225 goto error;
226 }
227
dae52e76
AB
228 bin->dwarf_fd = fd;
229 bin->dwarf_path = strdup(path);
230 if (!bin->dwarf_path) {
b5a8598f
AB
231 goto error;
232 }
dae52e76 233 bin->dwarf_info = dwarf_info;
b5a8598f
AB
234 free(cu);
235
236 return 0;
237
238error:
239 close(fd);
240 dwarf_end(dwarf_info);
241 g_free(dwarf_info);
242 free(cu);
243
244 return -1;
245}
246
247/**
dae52e76 248 * Try to set the dwarf_info for a given bin_info instance via the
b5a8598f
AB
249 * build ID method.
250 *
dae52e76 251 * @param bin bin_info instance for which to retrieve the
b5a8598f
AB
252 * DWARF info via build ID
253 * @returns 0 on success (i.e. dwarf_info set), -1 on failure
254 */
255static
dae52e76 256int bin_info_set_dwarf_info_build_id(struct bin_info *bin)
b5a8598f 257{
1b3f6ee3 258 int i = 0, ret = 0;
b5a8598f
AB
259 char *path = NULL, *build_id_file = NULL;
260 const char *dbg_dir = NULL;
1b3f6ee3 261 size_t build_id_file_len;
b5a8598f 262
dae52e76 263 if (!bin || !bin->build_id) {
b5a8598f
AB
264 goto error;
265 }
266
3be1e3c9 267 dbg_dir = opt_debug_info_dir ? : DEFAULT_DEBUG_DIR;
b5a8598f 268
5f07b6ce 269 /* 2 characters per byte printed in hex, +1 for '/' and +1 for '\0' */
dae52e76 270 build_id_file_len = (2 * bin->build_id_len) + 1 +
1b3f6ee3 271 strlen(BUILD_ID_SUFFIX) + 1;
b5a8598f
AB
272 build_id_file = malloc(build_id_file_len);
273 if (!build_id_file) {
274 goto error;
275 }
276
dae52e76
AB
277 snprintf(build_id_file, 4, "%02x/", bin->build_id[0]);
278 for (i = 1; i < bin->build_id_len; ++i) {
b5a8598f
AB
279 int path_idx = 3 + 2 * (i - 1);
280
dae52e76 281 snprintf(&build_id_file[path_idx], 3, "%02x", bin->build_id[i]);
b5a8598f 282 }
1b3f6ee3 283 strcat(build_id_file, BUILD_ID_SUFFIX);
b5a8598f 284
1b3f6ee3 285 path = g_build_path("/", dbg_dir, BUILD_ID_SUBDIR, build_id_file, NULL);
b5a8598f
AB
286 if (!path) {
287 goto error;
288 }
289
dae52e76 290 ret = bin_info_set_dwarf_info_from_path(bin, path);
b5a8598f
AB
291 if (ret) {
292 goto error;
293 }
294
295 goto end;
296
297error:
298 ret = -1;
299end:
300 free(build_id_file);
301 free(path);
302
303 return ret;
304}
305
306/**
307 * Tests whether the file located at path exists and has the expected
308 * checksum.
309 *
310 * This predicate is used when looking up separate debug info via the
311 * GNU debuglink method. The expected crc can be found .gnu_debuglink
312 * section in the original ELF file, along with the filename for the
313 * file containing the debug info.
314 *
315 * @param path Full path at which to look for the debug file
316 * @param crc Expected checksum for the debug file
317 * @returns 1 if the file exists and has the correct checksum,
318 * 0 otherwise
319 */
320static
321int is_valid_debug_file(char *path, uint32_t crc)
322{
323 int ret = 0, fd = -1;
324 uint32_t _crc = 0;
325
326 if (!path) {
327 goto end;
328 }
329
330 fd = open(path, O_RDONLY);
331 if (fd < 0) {
332 goto end;
333 }
334
335 ret = crc32(fd, &_crc);
336 if (ret) {
337 ret = 0;
338 goto end;
339 }
340
341 ret = (crc == _crc);
342
343end:
344 close(fd);
345 return ret;
346}
347
348/**
dae52e76 349 * Try to set the dwarf_info for a given bin_info instance via the
b5a8598f
AB
350 * build ID method.
351 *
dae52e76 352 * @param bin bin_info instance for which to retrieve the
b5a8598f
AB
353 * DWARF info via debug link
354 * @returns 0 on success (i.e. dwarf_info set), -1 on failure
355 */
356static
dae52e76 357int bin_info_set_dwarf_info_debug_link(struct bin_info *bin)
b5a8598f
AB
358{
359 int ret = 0;
360 const char *dbg_dir = NULL;
dae52e76 361 char *dir_name = NULL, *bin_dir = NULL, *path = NULL;
b5a8598f
AB
362 size_t max_path_len = 0;
363
dae52e76 364 if (!bin || !bin->dbg_link_filename) {
b5a8598f
AB
365 goto error;
366 }
367
3be1e3c9 368 dbg_dir = opt_debug_info_dir ? : DEFAULT_DEBUG_DIR;
b5a8598f 369
dae52e76 370 dir_name = dirname(bin->elf_path);
b5a8598f
AB
371 if (!dir_name) {
372 goto error;
373 }
374
dae52e76
AB
375 /* bin_dir is just dir_name with a trailing slash */
376 bin_dir = malloc(strlen(dir_name) + 2);
377 if (!bin_dir) {
b5a8598f
AB
378 goto error;
379 }
380
dae52e76
AB
381 strcpy(bin_dir, dir_name);
382 strcat(bin_dir, "/");
b5a8598f 383
dae52e76
AB
384 max_path_len = strlen(dbg_dir) + strlen(bin_dir) +
385 strlen(DEBUG_SUBDIR) + strlen(bin->dbg_link_filename)
b5a8598f
AB
386 + 1;
387 path = malloc(max_path_len);
388 if (!path) {
389 goto error;
390 }
391
dae52e76
AB
392 /* First look in the executable's dir */
393 strcpy(path, bin_dir);
394 strcat(path, bin->dbg_link_filename);
b5a8598f 395
dae52e76 396 if (is_valid_debug_file(path, bin->dbg_link_crc)) {
b5a8598f
AB
397 goto found;
398 }
399
400 /* If not found, look in .debug subdir */
dae52e76 401 strcpy(path, bin_dir);
b5a8598f 402 strcat(path, DEBUG_SUBDIR);
dae52e76 403 strcat(path, bin->dbg_link_filename);
b5a8598f 404
dae52e76 405 if (is_valid_debug_file(path, bin->dbg_link_crc)) {
b5a8598f
AB
406 goto found;
407 }
408
409 /* Lastly, look under the global debug directory */
410 strcpy(path, dbg_dir);
dae52e76
AB
411 strcat(path, bin_dir);
412 strcat(path, bin->dbg_link_filename);
b5a8598f 413
dae52e76 414 if (is_valid_debug_file(path, bin->dbg_link_crc)) {
b5a8598f
AB
415 goto found;
416 }
417
418error:
419 ret = -1;
420end:
421 free(path);
dae52e76 422 free(bin_dir);
b5a8598f
AB
423
424 return ret;
425
426found:
dae52e76 427 ret = bin_info_set_dwarf_info_from_path(bin, path);
b5a8598f
AB
428 if (ret) {
429 goto error;
430 }
431
432 goto end;
433}
434
435/**
436 * Initialize the DWARF info for a given executable.
437 *
dae52e76 438 * @param bin bin_info instance
b5a8598f
AB
439 * @returns 0 on success, -1 on failure
440 */
441static
dae52e76 442int bin_info_set_dwarf_info(struct bin_info *bin)
b5a8598f
AB
443{
444 int ret = 0;
445
dae52e76 446 if (!bin) {
b5a8598f
AB
447 goto error;
448 }
449
450 /* First try to set the DWARF info from the ELF file */
dae52e76 451 ret = bin_info_set_dwarf_info_from_path(bin, bin->elf_path);
b5a8598f
AB
452 if (!ret) {
453 goto end;
454 }
455
456 /*
457 * If that fails, try to find separate debug info via build ID
458 * and debug link.
459 */
dae52e76 460 ret = bin_info_set_dwarf_info_build_id(bin);
b5a8598f
AB
461 if (!ret) {
462 goto end;
463 }
464
dae52e76 465 ret = bin_info_set_dwarf_info_debug_link(bin);
b5a8598f
AB
466 if (!ret) {
467 goto end;
468 }
469
470error:
471 ret = -1;
472end:
473 return ret;
474}
475
b8652b58
AB
476/**
477 * Initialize the ELF file for a given executable.
478 *
dae52e76 479 * @param bin bin_info instance
b8652b58
AB
480 * @returns 0 on success, -1 on failure
481 */
482static
dae52e76 483int bin_info_set_elf_file(struct bin_info *bin)
b8652b58 484{
bfadaf12 485 int elf_fd = -1;
e362dc93 486 Elf *elf_file = NULL;
b8652b58 487
dae52e76 488 if (!bin) {
b8652b58
AB
489 goto error;
490 }
491
dae52e76 492 elf_fd = open(bin->elf_path, O_RDONLY);
b8652b58 493 if (elf_fd < 0) {
dae52e76 494 printf_verbose("Failed to open %s\n", bin->elf_path);
b8652b58
AB
495 goto error;
496 }
497
498 elf_file = elf_begin(elf_fd, ELF_C_READ, NULL);
499 if (!elf_file) {
1036949d 500 printf_debug("elf_begin failed: %s\n", elf_errmsg(-1));
b8652b58
AB
501 goto error;
502 }
503
504 if (elf_kind(elf_file) != ELF_K_ELF) {
1036949d 505 printf_verbose("Error: %s is not an ELF object\n",
dae52e76 506 bin->elf_path);
b8652b58
AB
507 goto error;
508 }
509
dae52e76
AB
510 bin->elf_fd = elf_fd;
511 bin->elf_file = elf_file;
b8652b58
AB
512 return 0;
513
514error:
bfadaf12
JG
515 if (elf_fd >= 0) {
516 close(elf_fd);
517 }
b8652b58
AB
518 elf_end(elf_file);
519 return -1;
520}
521
b5a8598f
AB
522BT_HIDDEN
523void source_location_destroy(struct source_location *src_loc)
524{
525 if (!src_loc) {
526 return;
527 }
528
529 free(src_loc->filename);
530 g_free(src_loc);
531}
483791a5 532
1c47ec6c
AB
533/**
534 * Append a string representation of an address offset to an existing
535 * string.
536 *
537 * On success, the out parameter `result` will contain the base string
538 * followed by the offset string of the form "+0x1234". On failure,
539 * `result` remains unchanged.
540 *
541 * @param base_str The string to which to append an offset string
542 * @param low_addr The lower virtual memory address, the base from
543 * which the offset is computed
544 * @param high_addr The higher virtual memory address
545 * @param result Out parameter, the base string followed by the
546 * offset string
547 * @returns 0 on success, -1 on failure
548 */
549static
dae52e76 550int bin_info_append_offset_str(const char *base_str, uint64_t low_addr,
1c47ec6c
AB
551 uint64_t high_addr, char **result)
552{
553 int ret;
554 uint64_t offset;
555 char *_result = NULL;
556 char offset_str[ADDR_STR_LEN];
557
558 if (!base_str || !result) {
559 goto error;
560 }
561
562 offset = high_addr - low_addr;
563
564 _result = malloc(strlen(base_str) + ADDR_STR_LEN);
565 if (!_result) {
566 goto error;
567 }
568
569 ret = snprintf(offset_str, ADDR_STR_LEN, "+%#0" PRIx64, offset);
570 if (ret < 0) {
571 goto error;
572 }
573 strcpy(_result, base_str);
574 strcat(_result, offset_str);
575 *result = _result;
576
577 return 0;
578
579error:
580 free(_result);
581 return -1;
582}
b5a8598f
AB
583
584/**
585 * Try to find the symbol closest to an address within a given ELF
586 * section.
587 *
588 * Only function symbols are taken into account. The symbol's address
589 * must precede `addr`. A symbol with a closer address might exist
590 * after `addr` but is irrelevant because it cannot encompass `addr`.
591 *
592 * On success, if found, the out parameters `sym` and `shdr` are
593 * set. On failure or if none are found, they remain unchanged.
594 *
595 * @param scn ELF section in which to look for the address
596 * @param addr Virtual memory address for which to find the
597 * nearest function symbol
598 * @param sym Out parameter, the nearest function symbol
599 * @param shdr Out parameter, the section header for scn
600 * @returns 0 on success, -1 on failure
601 */
602static
dae52e76 603int bin_info_get_nearest_symbol_from_section(Elf_Scn *scn, uint64_t addr,
b5a8598f
AB
604 GElf_Sym **sym, GElf_Shdr **shdr)
605{
606 int i;
607 size_t symbol_count;
608 Elf_Data *data = NULL;
609 GElf_Shdr *_shdr = NULL;
610 GElf_Sym *nearest_sym = NULL;
611
612 if (!scn || !sym || !shdr) {
613 goto error;
614 }
615
616 _shdr = g_new0(GElf_Shdr, 1);
617 if (!_shdr) {
618 goto error;
619 }
620
621 _shdr = gelf_getshdr(scn, _shdr);
622 if (!_shdr) {
623 goto error;
624 }
625
626 if (_shdr->sh_type != SHT_SYMTAB) {
627 /*
628 * We are only interested in symbol table (symtab)
629 * sections, skip this one.
630 */
631 goto end;
632 }
633
634 data = elf_getdata(scn, NULL);
635 if (!data) {
636 goto error;
637 }
638
639 symbol_count = _shdr->sh_size / _shdr->sh_entsize;
640
641 for (i = 0; i < symbol_count; ++i) {
642 GElf_Sym *cur_sym = NULL;
643
644 cur_sym = g_new0(GElf_Sym, 1);
645 if (!cur_sym) {
646 goto error;
647 }
648 cur_sym = gelf_getsym(data, i, cur_sym);
649 if (!cur_sym) {
650 goto error;
651 }
652 if (GELF_ST_TYPE(cur_sym->st_info) != STT_FUNC) {
653 /* We're only interested in the functions. */
654 g_free(cur_sym);
655 continue;
656 }
657
658 if (cur_sym->st_value <= addr &&
659 (!nearest_sym ||
660 cur_sym->st_value > nearest_sym->st_value)) {
661 g_free(nearest_sym);
662 nearest_sym = cur_sym;
663 } else {
664 g_free(cur_sym);
665 }
666 }
667
668end:
669 if (nearest_sym) {
670 *sym = nearest_sym;
671 *shdr = _shdr;
672 } else {
673 g_free(_shdr);
674 }
675
676 return 0;
677
678error:
679 g_free(nearest_sym);
680 g_free(_shdr);
681 return -1;
682}
683
684/**
685 * Get the name of the function containing a given address within an
686 * executable using ELF symbols.
687 *
688 * The function name is in fact the name of the nearest ELF symbol,
689 * followed by the offset in bytes between the address and the symbol
690 * (in hex), separated by a '+' character.
691 *
692 * If found, the out parameter `func_name` is set on success. On failure,
693 * it remains unchanged.
694 *
dae52e76 695 * @param bin bin_info instance for the executable containing
b5a8598f
AB
696 * the address
697 * @param addr Virtual memory address for which to find the
698 * function name
699 * @param func_name Out parameter, the function name
700 * @returns 0 on success, -1 on failure
701 */
702static
dae52e76 703int bin_info_lookup_elf_function_name(struct bin_info *bin, uint64_t addr,
b5a8598f
AB
704 char **func_name)
705{
706 /*
707 * TODO (possible optimisation): if an ELF has no symtab
708 * section, it has been stripped. Therefore, it would be wise
709 * to store a flag indicating the stripped status after the
710 * first iteration to prevent subsequent ones.
711 */
712 int ret = 0;
713 Elf_Scn *scn = NULL;
714 GElf_Sym *sym = NULL;
715 GElf_Shdr *shdr = NULL;
716 char *sym_name = NULL;
b5a8598f 717
b8652b58 718 /* Set ELF file if it hasn't been accessed yet. */
dae52e76
AB
719 if (!bin->elf_file) {
720 ret = bin_info_set_elf_file(bin);
b8652b58
AB
721 if (ret) {
722 /* Failed to set ELF file. */
723 goto error;
724 }
725 }
726
dae52e76 727 scn = elf_nextscn(bin->elf_file, scn);
b5a8598f
AB
728 if (!scn) {
729 goto error;
730 }
731
732 while (scn && !sym) {
dae52e76 733 ret = bin_info_get_nearest_symbol_from_section(
b5a8598f
AB
734 scn, addr, &sym, &shdr);
735 if (ret) {
736 goto error;
737 }
738
dae52e76 739 scn = elf_nextscn(bin->elf_file, scn);
b5a8598f
AB
740 }
741
742 if (sym) {
dae52e76 743 sym_name = elf_strptr(bin->elf_file, shdr->sh_link,
b5a8598f
AB
744 sym->st_name);
745 if (!sym_name) {
746 goto error;
747 }
748
dae52e76 749 ret = bin_info_append_offset_str(sym_name, sym->st_value, addr,
1c47ec6c
AB
750 func_name);
751 if (ret) {
b5a8598f
AB
752 goto error;
753 }
b5a8598f
AB
754 }
755
756 g_free(shdr);
757 g_free(sym);
758 return 0;
759
760error:
761 g_free(shdr);
762 g_free(sym);
b5a8598f
AB
763 return -1;
764}
765
766/**
767 * Get the name of the function containing a given address within a
768 * given compile unit (CU).
769 *
770 * If found, the out parameter `func_name` is set on success. On
771 * failure, it remains unchanged.
772 *
773 * @param cu bt_dwarf_cu instance which may contain the address
774 * @param addr Virtual memory address for which to find the
775 * function name
776 * @param func_name Out parameter, the function name
777 * @returns 0 on success, -1 on failure
778 */
779static
dae52e76 780int bin_info_lookup_cu_function_name(struct bt_dwarf_cu *cu, uint64_t addr,
b5a8598f
AB
781 char **func_name)
782{
302314ec
AB
783 int ret = 0;
784 bool found = false;
b5a8598f
AB
785 struct bt_dwarf_die *die = NULL;
786
787 if (!cu || !func_name) {
788 goto error;
789 }
790
791 die = bt_dwarf_die_create(cu);
792 if (!die) {
793 goto error;
794 }
795
796 while (bt_dwarf_die_next(die) == 0) {
797 int tag;
798
799 ret = bt_dwarf_die_get_tag(die, &tag);
800 if (ret) {
801 goto error;
802 }
803
804 if (tag == DW_TAG_subprogram) {
805 ret = bt_dwarf_die_contains_addr(die, addr, &found);
806 if (ret) {
807 goto error;
808 }
809
810 if (found) {
811 break;
812 }
813 }
814 }
815
816 if (found) {
1c47ec6c
AB
817 uint64_t low_addr = 0;
818 char *die_name = NULL;
819
d3c33bc6
AB
820 ret = bt_dwarf_die_get_name(die, &die_name);
821 if (ret) {
822 goto error;
823 }
824
825 ret = dwarf_lowpc(die->dwarf_die, &low_addr);
b5a8598f
AB
826 if (ret) {
827 goto error;
828 }
829
dae52e76 830 ret = bin_info_append_offset_str(die_name, low_addr, addr,
1c47ec6c
AB
831 func_name);
832 if (ret) {
d3c33bc6
AB
833 goto error;
834 }
b5a8598f
AB
835 }
836
837 bt_dwarf_die_destroy(die);
838 return 0;
839
840error:
841 bt_dwarf_die_destroy(die);
842 return -1;
843}
844
845/**
846 * Get the name of the function containing a given address within an
847 * executable using DWARF debug info.
848 *
849 * If found, the out parameter `func_name` is set on success. On
850 * failure, it remains unchanged.
851 *
dae52e76 852 * @param bin bin_info instance for the executable containing
b5a8598f
AB
853 * the address
854 * @param addr Virtual memory address for which to find the
855 * function name
856 * @param func_name Out parameter, the function name
857 * @returns 0 on success, -1 on failure
858 */
859static
dae52e76 860int bin_info_lookup_dwarf_function_name(struct bin_info *bin, uint64_t addr,
b5a8598f
AB
861 char **func_name)
862{
863 int ret = 0;
864 char *_func_name = NULL;
865 struct bt_dwarf_cu *cu = NULL;
866
dae52e76 867 if (!bin || !func_name) {
b5a8598f
AB
868 goto error;
869 }
870
dae52e76 871 cu = bt_dwarf_cu_create(bin->dwarf_info);
b5a8598f
AB
872 if (!cu) {
873 goto error;
874 }
875
876 while (bt_dwarf_cu_next(cu) == 0) {
dae52e76 877 ret = bin_info_lookup_cu_function_name(cu, addr, &_func_name);
b5a8598f
AB
878 if (ret) {
879 goto error;
880 }
881
882 if (_func_name) {
883 break;
884 }
885 }
886
887 if (_func_name) {
888 *func_name = _func_name;
fcd94e37
JG
889 } else {
890 goto error;
b5a8598f
AB
891 }
892
893 bt_dwarf_cu_destroy(cu);
894 return 0;
895
896error:
897 bt_dwarf_cu_destroy(cu);
898 return -1;
899}
900
901BT_HIDDEN
dae52e76 902int bin_info_lookup_function_name(struct bin_info *bin, uint64_t addr,
b5a8598f
AB
903 char **func_name)
904{
905 int ret = 0;
906 char *_func_name = NULL;
907
dae52e76 908 if (!bin || !func_name) {
b5a8598f
AB
909 goto error;
910 }
911
912 /* Set DWARF info if it hasn't been accessed yet. */
dae52e76
AB
913 if (!bin->dwarf_info && !bin->is_elf_only) {
914 ret = bin_info_set_dwarf_info(bin);
b5a8598f
AB
915 if (ret) {
916 /* Failed to set DWARF info, fallback to ELF. */
dae52e76 917 bin->is_elf_only = true;
b5a8598f
AB
918 }
919 }
920
dae52e76 921 if (!bin_info_has_address(bin, addr)) {
b5a8598f
AB
922 goto error;
923 }
924
925 /*
926 * Addresses in ELF and DWARF are relative to base address for
927 * PIC, so make the address argument relative too if needed.
928 */
dae52e76
AB
929 if (bin->is_pic) {
930 addr -= bin->low_addr;
dc419b6c
AB
931 }
932
dae52e76
AB
933 if (bin->is_elf_only) {
934 ret = bin_info_lookup_elf_function_name(bin, addr, &_func_name);
b5a8598f 935 } else {
dae52e76 936 ret = bin_info_lookup_dwarf_function_name(bin, addr, &_func_name);
b5a8598f
AB
937 }
938
dc419b6c 939 if (ret || !_func_name) {
b5a8598f
AB
940 goto error;
941 }
942
dc419b6c
AB
943 *func_name = _func_name;
944 return 0;
beef86dc 945
dc419b6c
AB
946error:
947 return -1;
948}
949
950BT_HIDDEN
dae52e76 951int bin_info_get_bin_loc(struct bin_info *bin, uint64_t addr, char **bin_loc)
dc419b6c
AB
952{
953 int ret = 0;
954 char *_bin_loc = NULL;
955
dae52e76 956 if (!bin || !bin_loc) {
dc419b6c 957 goto error;
b5a8598f
AB
958 }
959
dae52e76
AB
960 if (bin->is_pic) {
961 addr -= bin->low_addr;
dc419b6c
AB
962 ret = asprintf(&_bin_loc, "+%#0" PRIx64, addr);
963 } else {
964 ret = asprintf(&_bin_loc, "@%#0" PRIx64, addr);
965 }
966
967 if (ret == -1 || !_bin_loc) {
968 goto error;
969 }
970
971 *bin_loc = _bin_loc;
b5a8598f
AB
972 return 0;
973
974error:
975 return -1;
976}
977
978/**
979 * Predicate used to determine whether the children of a given DIE
980 * contain a specific address.
981 *
982 * More specifically, the parameter `die` is expected to be a
983 * subprogram (function) DIE, and this predicate tells whether any
984 * subroutines are inlined within this function and would contain
985 * `addr`.
986 *
302314ec
AB
987 * On success, the out parameter `contains` is set with the boolean
988 * value indicating whether the DIE's range covers `addr`. On failure,
989 * it remains unchanged.
990 *
b5a8598f
AB
991 * Do note that this function advances the position of `die`. If the
992 * address is found within one of its children, `die` will be pointing
993 * to that child upon returning from the function, allowing to extract
994 * the information deemed necessary.
995 *
302314ec
AB
996 * @param die The parent DIE in whose children the address will be
997 * looked for
998 * @param addr The address for which to look for in the DIEs
999 * @param contains Out parameter, true if addr is contained,
1000 * false if not
1001 * @returns Returns 0 on success, -1 on failure
b5a8598f
AB
1002 */
1003static
302314ec 1004int bin_info_child_die_has_address(struct bt_dwarf_die *die, uint64_t addr, bool *contains)
b5a8598f 1005{
302314ec
AB
1006 int ret = 0;
1007 bool _contains = false;
b5a8598f
AB
1008
1009 if (!die) {
1010 goto error;
1011 }
1012
1013 ret = bt_dwarf_die_child(die);
1014 if (ret) {
1015 goto error;
1016 }
1017
1018 do {
1019 int tag;
1020
1021 ret = bt_dwarf_die_get_tag(die, &tag);
1022 if (ret) {
1023 goto error;
1024 }
1025
1026 if (tag == DW_TAG_inlined_subroutine) {
302314ec 1027 ret = bt_dwarf_die_contains_addr(die, addr, &_contains);
b5a8598f
AB
1028 if (ret) {
1029 goto error;
1030 }
1031
1032 if (contains) {
b5a8598f
AB
1033 goto end;
1034 }
1035 }
1036 } while (bt_dwarf_die_next(die) == 0);
1037
1038end:
302314ec
AB
1039 *contains = _contains;
1040 return 0;
b5a8598f
AB
1041
1042error:
302314ec 1043 return -1;
b5a8598f
AB
1044}
1045
1046/**
1047 * Lookup the source location for a given address within a CU, making
1048 * the assumption that it is contained within an inline routine in a
1049 * function.
1050 *
1051 * @param cu bt_dwarf_cu instance in which to look for the address
1052 * @param addr The address for which to look for
1053 * @param src_loc Out parameter, the source location (filename and
1054 * line number) for the address
1055 * @returns 0 on success, -1 on failure
1056 */
1057static
dae52e76 1058int bin_info_lookup_cu_src_loc_inl(struct bt_dwarf_cu *cu, uint64_t addr,
b5a8598f
AB
1059 struct source_location **src_loc)
1060{
302314ec
AB
1061 int ret = 0;
1062 bool found = false;
b5a8598f
AB
1063 struct bt_dwarf_die *die = NULL;
1064 struct source_location *_src_loc = NULL;
1065
1066 if (!cu || !src_loc) {
1067 goto error;
1068 }
1069
1070 die = bt_dwarf_die_create(cu);
1071 if (!die) {
1072 goto error;
1073 }
1074
1075 while (bt_dwarf_die_next(die) == 0) {
1076 int tag;
1077
1078 ret = bt_dwarf_die_get_tag(die, &tag);
1079 if (ret) {
1080 goto error;
1081 }
1082
1083 if (tag == DW_TAG_subprogram) {
302314ec 1084 bool contains = false;
b5a8598f
AB
1085
1086 ret = bt_dwarf_die_contains_addr(die, addr, &contains);
1087 if (ret) {
1088 goto error;
1089 }
1090
1091 if (contains) {
1092 /*
1093 * Try to find an inlined subroutine
1094 * child of this DIE containing addr.
1095 */
302314ec
AB
1096 ret = bin_info_child_die_has_address(die, addr,
1097 &found);
1098 if(ret) {
1099 goto error;
1100 }
1101
b5a8598f
AB
1102 goto end;
1103 }
1104 }
1105 }
1106
1107end:
1108 if (found) {
1109 char *filename = NULL;
1110 uint64_t line_no;
1111
1112 _src_loc = g_new0(struct source_location, 1);
1113 if (!_src_loc) {
1114 goto error;
1115 }
1116
1117 ret = bt_dwarf_die_get_call_file(die, &filename);
1118 if (ret) {
1119 goto error;
1120 }
1121 ret = bt_dwarf_die_get_call_line(die, &line_no);
1122 if (ret) {
1123 free(filename);
1124 goto error;
1125 }
1126
1127 _src_loc->filename = filename;
1128 _src_loc->line_no = line_no;
1129 *src_loc = _src_loc;
1130 }
1131
1132 bt_dwarf_die_destroy(die);
1133 return 0;
1134
1135error:
1136 source_location_destroy(_src_loc);
1137 bt_dwarf_die_destroy(die);
1138 return -1;
1139}
1140
1141/**
1142 * Lookup the source location for a given address within a CU,
1143 * assuming that it is contained within an inlined function.
1144 *
1145 * A source location can be found regardless of inlining status for
1146 * this method, but in the case of an inlined function, the returned
1147 * source location will point not to the callsite but rather to the
1148 * definition site of the inline function.
1149 *
1150 * @param cu bt_dwarf_cu instance in which to look for the address
1151 * @param addr The address for which to look for
1152 * @param src_loc Out parameter, the source location (filename and
1153 * line number) for the address
1154 * @returns 0 on success, -1 on failure
1155 */
1156static
dae52e76 1157int bin_info_lookup_cu_src_loc_no_inl(struct bt_dwarf_cu *cu, uint64_t addr,
b5a8598f
AB
1158 struct source_location **src_loc)
1159{
1160 struct source_location *_src_loc = NULL;
1161 struct bt_dwarf_die *die = NULL;
1162 const char *filename = NULL;
1163 Dwarf_Line *line = NULL;
1164 Dwarf_Addr line_addr;
1165 int ret, line_no;
1166
1167 if (!cu || !src_loc) {
1168 goto error;
1169 }
1170
1171 die = bt_dwarf_die_create(cu);
1172 if (!die) {
1173 goto error;
1174 }
1175
1176 line = dwarf_getsrc_die(die->dwarf_die, addr);
1177 if (!line) {
1178 goto error;
1179 }
1180
1181 ret = dwarf_lineaddr(line, &line_addr);
1182 if (ret) {
1183 goto error;
1184 }
1185
1186 filename = dwarf_linesrc(line, NULL, NULL);
1187 if (!filename) {
1188 goto error;
1189 }
1190
1191 if (addr == line_addr) {
1192 _src_loc = g_new0(struct source_location, 1);
1193 if (!_src_loc) {
1194 goto error;
1195 }
1196
1197 ret = dwarf_lineno(line, &line_no);
1198 if (ret) {
1199 goto error;
1200 }
1201
1202 _src_loc->line_no = line_no;
1203 _src_loc->filename = strdup(filename);
1204 }
1205
1206 bt_dwarf_die_destroy(die);
1207
1208 if (_src_loc) {
1209 *src_loc = _src_loc;
1210 }
1211
1212 return 0;
1213
1214error:
1215 source_location_destroy(_src_loc);
1216 bt_dwarf_die_destroy(die);
1217 return -1;
1218}
1219
1220/**
1221 * Get the source location (file name and line number) for a given
1222 * address within a compile unit (CU).
1223 *
1224 * On success, the out parameter `src_loc` is set if found. On
1225 * failure, it remains unchanged.
1226 *
dae52e76 1227 * @param cu bt_dwarf_cu instance for the compile unit which
b5a8598f
AB
1228 * may contain the address
1229 * @param addr Virtual memory address for which to find the
1230 * source location
1231 * @param src_loc Out parameter, the source location
1232 * @returns 0 on success, -1 on failure
1233 */
1234static
dae52e76 1235int bin_info_lookup_cu_src_loc(struct bt_dwarf_cu *cu, uint64_t addr,
b5a8598f
AB
1236 struct source_location **src_loc)
1237{
1238 int ret = 0;
1239 struct source_location *_src_loc = NULL;
1240
1241 if (!cu || !src_loc) {
1242 goto error;
1243 }
1244
dae52e76 1245 ret = bin_info_lookup_cu_src_loc_inl(cu, addr, &_src_loc);
b5a8598f
AB
1246 if (ret) {
1247 goto error;
1248 }
1249
1250 if (_src_loc) {
1251 goto end;
1252 }
1253
dae52e76 1254 ret = bin_info_lookup_cu_src_loc_no_inl(cu, addr, &_src_loc);
b5a8598f
AB
1255 if (ret) {
1256 goto error;
1257 }
1258
1259 if (_src_loc) {
1260 goto end;
1261 }
1262
1263end:
1264 if (_src_loc) {
1265 *src_loc = _src_loc;
1266 }
1267
1268 return 0;
1269
1270error:
1271 source_location_destroy(_src_loc);
1272 return -1;
1273}
1274
1275BT_HIDDEN
dae52e76 1276int bin_info_lookup_source_location(struct bin_info *bin, uint64_t addr,
b5a8598f
AB
1277 struct source_location **src_loc)
1278{
1279 struct bt_dwarf_cu *cu = NULL;
1280 struct source_location *_src_loc = NULL;
1281
dae52e76 1282 if (!bin || !src_loc) {
b5a8598f
AB
1283 goto error;
1284 }
1285
1286 /* Set DWARF info if it hasn't been accessed yet. */
dae52e76
AB
1287 if (!bin->dwarf_info && !bin->is_elf_only) {
1288 if (bin_info_set_dwarf_info(bin)) {
b5a8598f 1289 /* Failed to set DWARF info. */
dae52e76 1290 bin->is_elf_only = true;
b5a8598f
AB
1291 }
1292 }
1293
dae52e76 1294 if (bin->is_elf_only) {
b5a8598f
AB
1295 /* We cannot lookup source location without DWARF info. */
1296 goto error;
1297 }
1298
dae52e76 1299 if (!bin_info_has_address(bin, addr)) {
b5a8598f
AB
1300 goto error;
1301 }
1302
1303 /*
1304 * Addresses in ELF and DWARF are relative to base address for
1305 * PIC, so make the address argument relative too if needed.
1306 */
dae52e76
AB
1307 if (bin->is_pic) {
1308 addr -= bin->low_addr;
b5a8598f
AB
1309 }
1310
dae52e76 1311 cu = bt_dwarf_cu_create(bin->dwarf_info);
b5a8598f
AB
1312 if (!cu) {
1313 goto error;
1314 }
1315
1316 while (bt_dwarf_cu_next(cu) == 0) {
1317 int ret;
1318
dae52e76 1319 ret = bin_info_lookup_cu_src_loc(cu, addr, &_src_loc);
b5a8598f
AB
1320 if (ret) {
1321 goto error;
1322 }
1323
1324 if (_src_loc) {
1325 break;
1326 }
1327 }
1328
1329 bt_dwarf_cu_destroy(cu);
1330 if (_src_loc) {
1331 *src_loc = _src_loc;
1332 }
1333
1334 return 0;
1335
1336error:
1337 source_location_destroy(_src_loc);
1338 bt_dwarf_cu_destroy(cu);
1339 return -1;
1340}
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