4 * Babeltrace - Executable and Shared Object Debug Info Reader
6 * Copyright 2015 Antoine Busque <abusque@efficios.com>
8 * Author: Antoine Busque <abusque@efficios.com>
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:
17 * The above copyright notice and this permission notice shall be included in
18 * all copies or substantial portions of the Software.
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
29 #define BT_LOG_TAG "PLUGIN-CTF-LTTNG-UTILS-DEBUG-INFO-FLT-BIN-INFO"
45 #include <babeltrace/common-internal.h>
53 * An address printed in hex is at most 20 bytes (16 for 64-bits +
54 * leading 0x + optional leading '+' if addr is an offset + null
57 #define ADDR_STR_LEN 20
58 #define BUILD_ID_NOTE_NAME "GNU"
61 int bin_info_init(void)
65 if (elf_version(EV_CURRENT
) == EV_NONE
) {
66 BT_LOGD("ELF library initialization failed: %s.",
75 struct bin_info
*bin_info_create(struct bt_fd_cache
*fdc
, const char *path
,
76 uint64_t low_addr
, uint64_t memsz
, bool is_pic
,
77 const char *debug_info_dir
, const char *target_prefix
)
79 struct bin_info
*bin
= NULL
;
87 bin
= g_new0(struct bin_info
, 1);
93 bin
->elf_path
= g_build_filename(target_prefix
, path
, NULL
);
95 bin
->elf_path
= g_strdup(path
);
102 if (debug_info_dir
) {
103 bin
->debug_info_dir
= g_strdup(debug_info_dir
);
104 if (!bin
->debug_info_dir
) {
109 bin
->is_pic
= is_pic
;
111 bin
->low_addr
= low_addr
;
112 bin
->high_addr
= bin
->low_addr
+ bin
->memsz
;
113 bin
->build_id
= NULL
;
114 bin
->build_id_len
= 0;
115 bin
->file_build_id_matches
= false;
121 bin_info_destroy(bin
);
126 void bin_info_destroy(struct bin_info
*bin
)
132 dwarf_end(bin
->dwarf_info
);
134 g_free(bin
->debug_info_dir
);
135 g_free(bin
->elf_path
);
136 g_free(bin
->dwarf_path
);
137 g_free(bin
->build_id
);
138 g_free(bin
->dbg_link_filename
);
140 elf_end(bin
->elf_file
);
142 bt_fd_cache_put_handle(bin
->fd_cache
, bin
->elf_handle
);
143 bt_fd_cache_put_handle(bin
->fd_cache
, bin
->dwarf_handle
);
149 * Initialize the ELF file for a given executable.
151 * @param bin bin_info instance
152 * @returns 0 on success, negative value on error.
155 int bin_info_set_elf_file(struct bin_info
*bin
)
157 struct bt_fd_cache_handle
*elf_handle
= NULL
;
158 Elf
*elf_file
= NULL
;
164 elf_handle
= bt_fd_cache_get_handle(bin
->fd_cache
, bin
->elf_path
);
166 BT_LOGD("Failed to open %s", bin
->elf_path
);
169 bin
->elf_handle
= elf_handle
;
171 elf_file
= elf_begin(bt_fd_cache_handle_get_fd(bin
->elf_handle
),
174 BT_LOGE("elf_begin failed: %s", elf_errmsg(-1));
178 bin
->elf_file
= elf_file
;
180 if (elf_kind(elf_file
) != ELF_K_ELF
) {
181 BT_LOGE("Error: %s is not an ELF object", bin
->elf_path
);
188 bt_fd_cache_put_handle(bin
->fd_cache
, elf_handle
);
194 * From a note section data struct, check if it is a build id note.
196 * @param note_data Pointer to a note section
198 * @returns 1 on match, 0 if `buf` does not contain a
199 * valid build id note
202 int is_build_id_note_section(Elf_Data
*note_data
)
204 size_t name_offset
, desc_offset
;
205 GElf_Nhdr note_header
;
209 * Discard the return value as it contains the size of the note section
210 * and we don't need it.
212 (void) gelf_getnote(note_data
, 0, ¬e_header
, &name_offset
,
216 * Check the note name length. The name_sz field includes the
217 * terminating null byte.
219 if (note_header
.n_namesz
!= sizeof(BUILD_ID_NOTE_NAME
)) {
223 /* Check the note type. */
224 if (note_header
.n_type
!= NT_GNU_BUILD_ID
) {
228 /* Check the note name. */
229 if (memcmp(note_data
->d_buf
+ name_offset
, BUILD_ID_NOTE_NAME
,
230 note_header
.n_namesz
) != 0) {
241 * From a build id note section data struct, check if the build id it contains
242 * is identical to the build id passed as parameter.
244 * @param note_data Pointer to the file build id note section.
245 * @param build_id Pointer to a build id to compare to.
246 * @param build_id_len length of the build id.
248 * @returns 1 on match, 0 otherwise.
251 int is_build_id_note_section_matching(Elf_Data
*note_data
,
252 uint8_t *build_id
, size_t build_id_len
)
254 size_t name_offset
, desc_offset
;
255 GElf_Nhdr note_header
;
257 if (build_id_len
<= 0) {
262 * Discard the return value as it contains the size of the note section
263 * and we don't need it.
265 (void) gelf_getnote(note_data
, 0, ¬e_header
, &name_offset
,
269 * Compare the binary build id with the supplied build id.
271 if (memcmp(build_id
, note_data
->d_buf
+ desc_offset
,
272 build_id_len
) == 0) {
280 * Checks if the build id stored in `bin` (bin->build_id) is matching the build
281 * id of the ondisk file (bin->elf_file).
283 * @param bin bin_info instance
284 * @param build_id build id to compare ot the on disk file
285 * @param build_id_len length of the build id
287 * @returns 1 on if the build id of stored in `bin` matches
288 * the build id of the ondisk file.
289 * 0 on if they are different or an error occured.
292 int is_build_id_matching(struct bin_info
*bin
)
294 int ret
, is_build_id
, is_matching
= 0;
295 Elf_Scn
*curr_section
= NULL
, *next_section
= NULL
;
296 GElf_Shdr curr_section_hdr
;
298 if (!bin
->build_id
) {
302 /* Set ELF file if it hasn't been accessed yet. */
303 if (!bin
->elf_file
) {
304 ret
= bin_info_set_elf_file(bin
);
306 /* Failed to set ELF file. */
311 next_section
= elf_nextscn(bin
->elf_file
, curr_section
);
316 while (next_section
) {
317 Elf_Data
*note_data
= NULL
;
319 curr_section
= next_section
;
320 next_section
= elf_nextscn(bin
->elf_file
, curr_section
);
322 if (!gelf_getshdr(curr_section
, &curr_section_hdr
)) {
326 if (curr_section_hdr
.sh_type
!= SHT_NOTE
) {
331 * elf_getdata() translates the data to native byte order.
333 note_data
= elf_getdata(curr_section
, NULL
);
338 /* Check if the note is of the build-id type. */
339 is_build_id
= is_build_id_note_section(note_data
);
345 * Compare the build id of the on-disk file and
346 * the build id recorded in the trace.
348 is_matching
= is_build_id_note_section_matching(
349 note_data
, bin
->build_id
, bin
->build_id_len
);
359 int bin_info_set_build_id(struct bin_info
*bin
, uint8_t *build_id
,
362 if (!bin
|| !build_id
) {
366 /* Set the build id. */
367 bin
->build_id
= g_new0(uint8_t, build_id_len
);
368 if (!bin
->build_id
) {
372 memcpy(bin
->build_id
, build_id
, build_id_len
);
373 bin
->build_id_len
= build_id_len
;
376 * Check if the file found on the file system has the same build id
377 * that what was recorded in the trace.
379 bin
->file_build_id_matches
= is_build_id_matching(bin
);
380 if (!bin
->file_build_id_matches
) {
381 BT_LOGD_STR("Supplied Build ID does not match Build ID of the "
382 "binary or library found on the file system.");
387 * Reset the is_elf_only flag in case it had been set
388 * previously, because we might find separate debug info using
389 * the new build id information.
391 bin
->is_elf_only
= false;
400 int bin_info_set_debug_link(struct bin_info
*bin
, const char *filename
,
403 if (!bin
|| !filename
) {
407 bin
->dbg_link_filename
= g_strdup(filename
);
408 if (!bin
->dbg_link_filename
) {
412 bin
->dbg_link_crc
= crc
;
415 * Reset the is_elf_only flag in case it had been set
416 * previously, because we might find separate debug info using
417 * the new build id information.
419 bin
->is_elf_only
= false;
429 * Tries to read DWARF info from the location given by path, and
430 * attach it to the given bin_info instance if it exists.
432 * @param bin bin_info instance for which to set DWARF info
433 * @param path Presumed location of the DWARF info
434 * @returns 0 on success, negative value on failure
437 int bin_info_set_dwarf_info_from_path(struct bin_info
*bin
, char *path
)
440 struct bt_fd_cache_handle
*dwarf_handle
= NULL
;
441 struct bt_dwarf_cu
*cu
= NULL
;
442 Dwarf
*dwarf_info
= NULL
;
448 dwarf_handle
= bt_fd_cache_get_handle(bin
->fd_cache
, path
);
453 dwarf_info
= dwarf_begin(bt_fd_cache_handle_get_fd(dwarf_handle
),
460 * Check if the dwarf info has any CU. If not, the
461 * executable's object file contains no DWARF info.
463 cu
= bt_dwarf_cu_create(dwarf_info
);
468 ret
= bt_dwarf_cu_next(cu
);
473 bin
->dwarf_handle
= dwarf_handle
;
474 bin
->dwarf_path
= g_strdup(path
);
475 if (!bin
->dwarf_path
) {
478 bin
->dwarf_info
= dwarf_info
;
484 bt_fd_cache_put_handle(bin
->fd_cache
, dwarf_handle
);
485 dwarf_end(dwarf_info
);
493 * Try to set the dwarf_info for a given bin_info instance via the
496 * @param bin bin_info instance for which to retrieve the
497 * DWARF info via build ID
498 * @returns 0 on success (i.e. dwarf_info set), -1 on failure
501 int bin_info_set_dwarf_info_build_id(struct bin_info
*bin
)
504 char *path
= NULL
, *build_id_file
= NULL
;
505 const char *dbg_dir
= NULL
;
506 size_t build_id_char_len
, build_id_suffix_char_len
, build_id_file_len
;
508 if (!bin
|| !bin
->build_id
) {
512 dbg_dir
= bin
->debug_info_dir
? bin
->debug_info_dir
: DEFAULT_DEBUG_DIR
;
514 /* 2 characters per byte printed in hex, +1 for '/' and +1 for '\0' */
515 build_id_char_len
= (2 * bin
->build_id_len
) + 1;
516 build_id_suffix_char_len
= strlen(BUILD_ID_SUFFIX
) + 1;
517 build_id_file_len
= build_id_char_len
+ build_id_suffix_char_len
;
518 build_id_file
= g_new0(gchar
, build_id_file_len
);
519 if (!build_id_file
) {
523 g_snprintf(build_id_file
, 4, "%02x/", bin
->build_id
[0]);
524 for (i
= 1; i
< bin
->build_id_len
; ++i
) {
525 int path_idx
= 3 + 2 * (i
- 1);
527 g_snprintf(&build_id_file
[path_idx
], 3, "%02x", bin
->build_id
[i
]);
529 g_snprintf(&build_id_file
[build_id_char_len
], build_id_suffix_char_len
,
532 path
= g_build_filename(dbg_dir
, BUILD_ID_SUBDIR
, build_id_file
, NULL
);
537 ret
= bin_info_set_dwarf_info_from_path(bin
, path
);
554 * Tests whether the file located at path exists and has the expected
557 * This predicate is used when looking up separate debug info via the
558 * GNU debuglink method. The expected crc can be found .gnu_debuglink
559 * section in the original ELF file, along with the filename for the
560 * file containing the debug info.
562 * @param path Full path at which to look for the debug file
563 * @param crc Expected checksum for the debug file
564 * @returns 1 if the file exists and has the correct checksum,
568 int is_valid_debug_file(struct bin_info
*bin
, char *path
, uint32_t crc
)
571 struct bt_fd_cache_handle
*debug_handle
= NULL
;
578 debug_handle
= bt_fd_cache_get_handle(bin
->fd_cache
, path
);
583 ret
= crc32(bt_fd_cache_handle_get_fd(debug_handle
), &_crc
);
592 bt_fd_cache_put_handle(bin
->fd_cache
, debug_handle
);
597 * Try to set the dwarf_info for a given bin_info instance via the
600 * @param bin bin_info instance for which to retrieve the
601 * DWARF info via debug link
602 * @returns 0 on success (i.e. dwarf_info set), -1 on failure
605 int bin_info_set_dwarf_info_debug_link(struct bin_info
*bin
)
608 const gchar
*dbg_dir
= NULL
;
609 gchar
*bin_dir
= NULL
, *dir_name
= NULL
, *path
= NULL
;
611 if (!bin
|| !bin
->dbg_link_filename
) {
615 dbg_dir
= bin
->debug_info_dir
? bin
->debug_info_dir
: DEFAULT_DEBUG_DIR
;
616 dir_name
= g_path_get_dirname(bin
->elf_path
);
621 bin_dir
= g_strconcat(dir_name
, "/", NULL
);
623 /* First look in the executable's dir */
624 path
= g_strconcat(bin_dir
, bin
->dbg_link_filename
, NULL
);
626 if (is_valid_debug_file(bin
, path
, bin
->dbg_link_crc
)) {
630 /* If not found, look in .debug subdir */
632 path
= g_strconcat(bin_dir
, DEBUG_SUBDIR
, bin
->dbg_link_filename
, NULL
);
634 if (is_valid_debug_file(bin
, path
, bin
->dbg_link_crc
)) {
638 /* Lastly, look under the global debug directory */
641 path
= g_strconcat(dbg_dir
, bin_dir
, bin
->dbg_link_filename
, NULL
);
642 if (is_valid_debug_file(bin
, path
, bin
->dbg_link_crc
)) {
656 ret
= bin_info_set_dwarf_info_from_path(bin
, path
);
665 * Initialize the DWARF info for a given executable.
667 * @param bin bin_info instance
668 * @returns 0 on success, negative value on failure
671 int bin_info_set_dwarf_info(struct bin_info
*bin
)
680 /* First try to set the DWARF info from the ELF file */
681 ret
= bin_info_set_dwarf_info_from_path(bin
, bin
->elf_path
);
687 * If that fails, try to find separate debug info via build ID
690 ret
= bin_info_set_dwarf_info_build_id(bin
);
695 ret
= bin_info_set_dwarf_info_debug_link(bin
);
705 void source_location_destroy(struct source_location
*src_loc
)
711 free(src_loc
->filename
);
716 * Append a string representation of an address offset to an existing
719 * On success, the out parameter `result` will contain the base string
720 * followed by the offset string of the form "+0x1234". On failure,
721 * `result` remains unchanged.
723 * @param base_str The string to which to append an offset string
724 * @param low_addr The lower virtual memory address, the base from
725 * which the offset is computed
726 * @param high_addr The higher virtual memory address
727 * @param result Out parameter, the base string followed by the
729 * @returns 0 on success, -1 on failure
732 int bin_info_append_offset_str(const char *base_str
, uint64_t low_addr
,
733 uint64_t high_addr
, char **result
)
736 char *_result
= NULL
;
738 if (!base_str
|| !result
) {
742 offset
= high_addr
- low_addr
;
744 _result
= g_strdup_printf("%s+%#0" PRIx64
, base_str
, offset
);
758 * Try to find the symbol closest to an address within a given ELF
761 * Only function symbols are taken into account. The symbol's address
762 * must precede `addr`. A symbol with a closer address might exist
763 * after `addr` but is irrelevant because it cannot encompass `addr`.
765 * On success, if found, the out parameters `sym` and `shdr` are
766 * set. On failure or if none are found, they remain unchanged.
768 * @param scn ELF section in which to look for the address
769 * @param addr Virtual memory address for which to find the
770 * nearest function symbol
771 * @param sym Out parameter, the nearest function symbol
772 * @param shdr Out parameter, the section header for scn
773 * @returns 0 on success, -1 on failure
776 int bin_info_get_nearest_symbol_from_section(Elf_Scn
*scn
, uint64_t addr
,
777 GElf_Sym
**sym
, GElf_Shdr
**shdr
)
781 Elf_Data
*data
= NULL
;
782 GElf_Shdr
*_shdr
= NULL
;
783 GElf_Sym
*nearest_sym
= NULL
;
785 if (!scn
|| !sym
|| !shdr
) {
789 _shdr
= g_new0(GElf_Shdr
, 1);
794 _shdr
= gelf_getshdr(scn
, _shdr
);
799 if (_shdr
->sh_type
!= SHT_SYMTAB
) {
801 * We are only interested in symbol table (symtab)
802 * sections, skip this one.
807 data
= elf_getdata(scn
, NULL
);
812 symbol_count
= _shdr
->sh_size
/ _shdr
->sh_entsize
;
814 for (i
= 0; i
< symbol_count
; ++i
) {
815 GElf_Sym
*cur_sym
= NULL
;
817 cur_sym
= g_new0(GElf_Sym
, 1);
821 cur_sym
= gelf_getsym(data
, i
, cur_sym
);
825 if (GELF_ST_TYPE(cur_sym
->st_info
) != STT_FUNC
) {
826 /* We're only interested in the functions. */
831 if (cur_sym
->st_value
<= addr
&&
833 cur_sym
->st_value
> nearest_sym
->st_value
)) {
835 nearest_sym
= cur_sym
;
858 * Get the name of the function containing a given address within an
859 * executable using ELF symbols.
861 * The function name is in fact the name of the nearest ELF symbol,
862 * followed by the offset in bytes between the address and the symbol
863 * (in hex), separated by a '+' character.
865 * If found, the out parameter `func_name` is set on success. On failure,
866 * it remains unchanged.
868 * @param bin bin_info instance for the executable containing
870 * @param addr Virtual memory address for which to find the
872 * @param func_name Out parameter, the function name
873 * @returns 0 on success, -1 on failure
876 int bin_info_lookup_elf_function_name(struct bin_info
*bin
, uint64_t addr
,
880 * TODO (possible optimisation): if an ELF has no symtab
881 * section, it has been stripped. Therefore, it would be wise
882 * to store a flag indicating the stripped status after the
883 * first iteration to prevent subsequent ones.
887 GElf_Sym
*sym
= NULL
;
888 GElf_Shdr
*shdr
= NULL
;
889 char *sym_name
= NULL
;
891 /* Set ELF file if it hasn't been accessed yet. */
892 if (!bin
->elf_file
) {
893 ret
= bin_info_set_elf_file(bin
);
895 /* Failed to set ELF file. */
900 scn
= elf_nextscn(bin
->elf_file
, scn
);
905 while (scn
&& !sym
) {
906 ret
= bin_info_get_nearest_symbol_from_section(
907 scn
, addr
, &sym
, &shdr
);
912 scn
= elf_nextscn(bin
->elf_file
, scn
);
916 sym_name
= elf_strptr(bin
->elf_file
, shdr
->sh_link
,
922 ret
= bin_info_append_offset_str(sym_name
, sym
->st_value
, addr
,
940 * Get the name of the function containing a given address within a
941 * given compile unit (CU).
943 * If found, the out parameter `func_name` is set on success. On
944 * failure, it remains unchanged.
946 * @param cu bt_dwarf_cu instance which may contain the address
947 * @param addr Virtual memory address for which to find the
949 * @param func_name Out parameter, the function name
950 * @returns 0 on success, -1 on failure
953 int bin_info_lookup_cu_function_name(struct bt_dwarf_cu
*cu
, uint64_t addr
,
958 struct bt_dwarf_die
*die
= NULL
;
960 if (!cu
|| !func_name
) {
964 die
= bt_dwarf_die_create(cu
);
969 while (bt_dwarf_die_next(die
) == 0) {
972 ret
= bt_dwarf_die_get_tag(die
, &tag
);
977 if (tag
== DW_TAG_subprogram
) {
978 ret
= bt_dwarf_die_contains_addr(die
, addr
, &found
);
990 uint64_t low_addr
= 0;
991 char *die_name
= NULL
;
993 ret
= bt_dwarf_die_get_name(die
, &die_name
);
998 ret
= dwarf_lowpc(die
->dwarf_die
, &low_addr
);
1004 ret
= bin_info_append_offset_str(die_name
, low_addr
, addr
,
1012 bt_dwarf_die_destroy(die
);
1016 bt_dwarf_die_destroy(die
);
1021 * Get the name of the function containing a given address within an
1022 * executable using DWARF debug info.
1024 * If found, the out parameter `func_name` is set on success. On
1025 * failure, it remains unchanged.
1027 * @param bin bin_info instance for the executable containing
1029 * @param addr Virtual memory address for which to find the
1031 * @param func_name Out parameter, the function name
1032 * @returns 0 on success, -1 on failure
1035 int bin_info_lookup_dwarf_function_name(struct bin_info
*bin
, uint64_t addr
,
1039 char *_func_name
= NULL
;
1040 struct bt_dwarf_cu
*cu
= NULL
;
1042 if (!bin
|| !func_name
) {
1046 cu
= bt_dwarf_cu_create(bin
->dwarf_info
);
1051 while (bt_dwarf_cu_next(cu
) == 0) {
1052 ret
= bin_info_lookup_cu_function_name(cu
, addr
, &_func_name
);
1063 *func_name
= _func_name
;
1068 bt_dwarf_cu_destroy(cu
);
1072 bt_dwarf_cu_destroy(cu
);
1077 int bin_info_lookup_function_name(struct bin_info
*bin
,
1078 uint64_t addr
, char **func_name
)
1081 char *_func_name
= NULL
;
1083 if (!bin
|| !func_name
) {
1088 * If the bin_info has a build id but it does not match the build id
1089 * that was found on the file system, return an error.
1091 if (bin
->build_id
&& !bin
->file_build_id_matches
) {
1095 /* Set DWARF info if it hasn't been accessed yet. */
1096 if (!bin
->dwarf_info
&& !bin
->is_elf_only
) {
1097 ret
= bin_info_set_dwarf_info(bin
);
1099 BT_LOGD_STR("Failed to set bin dwarf info, falling "
1100 "back to ELF lookup.");
1101 /* Failed to set DWARF info, fallback to ELF. */
1102 bin
->is_elf_only
= true;
1106 if (!bin_info_has_address(bin
, addr
)) {
1111 * Addresses in ELF and DWARF are relative to base address for
1112 * PIC, so make the address argument relative too if needed.
1115 addr
-= bin
->low_addr
;
1118 if (bin
->is_elf_only
) {
1119 ret
= bin_info_lookup_elf_function_name(bin
, addr
,
1122 BT_LOGD("Failed to lookup function name (ELF): "
1126 ret
= bin_info_lookup_dwarf_function_name(bin
, addr
,
1129 BT_LOGD("Failed to lookup function name (DWARF): "
1134 *func_name
= _func_name
;
1142 int bin_info_get_bin_loc(struct bin_info
*bin
, uint64_t addr
, char **bin_loc
)
1144 gchar
*_bin_loc
= NULL
;
1146 if (!bin
|| !bin_loc
) {
1151 * If the bin_info has a build id but it does not match the build id
1152 * that was found on the file system, return an error.
1154 if (bin
->build_id
&& !bin
->file_build_id_matches
) {
1159 addr
-= bin
->low_addr
;
1160 _bin_loc
= g_strdup_printf("+%#0" PRIx64
, addr
);
1162 _bin_loc
= g_strdup_printf("@%#0" PRIx64
, addr
);
1169 *bin_loc
= _bin_loc
;
1177 * Predicate used to determine whether the children of a given DIE
1178 * contain a specific address.
1180 * More specifically, the parameter `die` is expected to be a
1181 * subprogram (function) DIE, and this predicate tells whether any
1182 * subroutines are inlined within this function and would contain
1185 * On success, the out parameter `contains` is set with the boolean
1186 * value indicating whether the DIE's range covers `addr`. On failure,
1187 * it remains unchanged.
1189 * Do note that this function advances the position of `die`. If the
1190 * address is found within one of its children, `die` will be pointing
1191 * to that child upon returning from the function, allowing to extract
1192 * the information deemed necessary.
1194 * @param die The parent DIE in whose children the address will be
1196 * @param addr The address for which to look for in the DIEs
1197 * @param contains Out parameter, true if addr is contained,
1199 * @returns Returns 0 on success, -1 on failure
1202 int bin_info_child_die_has_address(struct bt_dwarf_die
*die
, uint64_t addr
, bool *contains
)
1205 bool _contains
= false;
1211 ret
= bt_dwarf_die_child(die
);
1217 ret
= bt_dwarf_die_contains_addr(die
, addr
, &_contains
);
1224 * The address is within the range of the current DIE
1229 ret
= bt_dwarf_die_get_tag(die
, &tag
);
1234 if (tag
== DW_TAG_inlined_subroutine
) {
1235 /* Found the tracepoint. */
1239 if (bt_dwarf_die_has_children(die
)) {
1241 * Look for the address in the children DIEs.
1243 ret
= bt_dwarf_die_child(die
);
1249 } while (bt_dwarf_die_next(die
) == 0);
1252 *contains
= _contains
;
1260 * Lookup the source location for a given address within a CU, making
1261 * the assumption that it is contained within an inline routine in a
1264 * @param cu bt_dwarf_cu instance in which to look for the address
1265 * @param addr The address for which to look for
1266 * @param src_loc Out parameter, the source location (filename and
1267 * line number) for the address
1268 * @returns 0 on success, -1 on failure
1271 int bin_info_lookup_cu_src_loc_inl(struct bt_dwarf_cu
*cu
, uint64_t addr
,
1272 struct source_location
**src_loc
)
1276 struct bt_dwarf_die
*die
= NULL
;
1277 struct source_location
*_src_loc
= NULL
;
1279 if (!cu
|| !src_loc
) {
1283 die
= bt_dwarf_die_create(cu
);
1288 while (bt_dwarf_die_next(die
) == 0) {
1291 ret
= bt_dwarf_die_get_tag(die
, &tag
);
1296 if (tag
== DW_TAG_subprogram
) {
1297 bool contains
= false;
1299 ret
= bt_dwarf_die_contains_addr(die
, addr
, &contains
);
1306 * Try to find an inlined subroutine
1307 * child of this DIE containing addr.
1309 ret
= bin_info_child_die_has_address(die
, addr
,
1322 char *filename
= NULL
;
1325 _src_loc
= g_new0(struct source_location
, 1);
1330 ret
= bt_dwarf_die_get_call_file(die
, &filename
);
1334 ret
= bt_dwarf_die_get_call_line(die
, &line_no
);
1340 _src_loc
->filename
= filename
;
1341 _src_loc
->line_no
= line_no
;
1342 *src_loc
= _src_loc
;
1345 bt_dwarf_die_destroy(die
);
1349 source_location_destroy(_src_loc
);
1350 bt_dwarf_die_destroy(die
);
1355 * Lookup the source location for a given address within a CU,
1356 * assuming that it is contained within an inlined function.
1358 * A source location can be found regardless of inlining status for
1359 * this method, but in the case of an inlined function, the returned
1360 * source location will point not to the callsite but rather to the
1361 * definition site of the inline function.
1363 * @param cu bt_dwarf_cu instance in which to look for the address
1364 * @param addr The address for which to look for
1365 * @param src_loc Out parameter, the source location (filename and
1366 * line number) for the address. Set only if the address
1367 * is found and resolved successfully
1369 * @returns 0 on success, -1 on failure
1372 int bin_info_lookup_cu_src_loc_no_inl(struct bt_dwarf_cu
*cu
, uint64_t addr
,
1373 struct source_location
**src_loc
)
1375 struct source_location
*_src_loc
= NULL
;
1376 struct bt_dwarf_die
*die
= NULL
;
1377 const char *filename
= NULL
;
1378 Dwarf_Line
*line
= NULL
;
1379 Dwarf_Addr line_addr
;
1382 if (!cu
|| !src_loc
) {
1386 die
= bt_dwarf_die_create(cu
);
1391 line
= dwarf_getsrc_die(die
->dwarf_die
, addr
);
1393 /* This is not an error. The caller needs to keep looking. */
1397 ret
= dwarf_lineaddr(line
, &line_addr
);
1402 filename
= dwarf_linesrc(line
, NULL
, NULL
);
1407 if (addr
== line_addr
) {
1408 _src_loc
= g_new0(struct source_location
, 1);
1413 ret
= dwarf_lineno(line
, &line_no
);
1418 _src_loc
->line_no
= line_no
;
1419 _src_loc
->filename
= g_strdup(filename
);
1422 bt_dwarf_die_destroy(die
);
1425 *src_loc
= _src_loc
;
1432 source_location_destroy(_src_loc
);
1433 bt_dwarf_die_destroy(die
);
1438 * Get the source location (file name and line number) for a given
1439 * address within a compile unit (CU).
1441 * On success, the out parameter `src_loc` is set if found. On
1442 * failure, it remains unchanged.
1444 * @param cu bt_dwarf_cu instance for the compile unit which
1445 * may contain the address
1446 * @param addr Virtual memory address for which to find the
1448 * @param src_loc Out parameter, the source location
1449 * @returns 0 on success, -1 on failure
1452 int bin_info_lookup_cu_src_loc(struct bt_dwarf_cu
*cu
, uint64_t addr
,
1453 struct source_location
**src_loc
)
1456 struct source_location
*_src_loc
= NULL
;
1458 if (!cu
|| !src_loc
) {
1462 ret
= bin_info_lookup_cu_src_loc_inl(cu
, addr
, &_src_loc
);
1471 ret
= bin_info_lookup_cu_src_loc_no_inl(cu
, addr
, &_src_loc
);
1482 *src_loc
= _src_loc
;
1488 source_location_destroy(_src_loc
);
1493 int bin_info_lookup_source_location(struct bin_info
*bin
, uint64_t addr
,
1494 struct source_location
**src_loc
)
1496 struct bt_dwarf_cu
*cu
= NULL
;
1497 struct source_location
*_src_loc
= NULL
;
1499 if (!bin
|| !src_loc
) {
1504 * If the bin_info has a build id but it does not match the build id
1505 * that was found on the file system, return an error.
1507 if (bin
->build_id
&& !bin
->file_build_id_matches
) {
1511 /* Set DWARF info if it hasn't been accessed yet. */
1512 if (!bin
->dwarf_info
&& !bin
->is_elf_only
) {
1513 if (bin_info_set_dwarf_info(bin
)) {
1514 /* Failed to set DWARF info. */
1515 bin
->is_elf_only
= true;
1519 if (bin
->is_elf_only
) {
1520 /* We cannot lookup source location without DWARF info. */
1524 if (!bin_info_has_address(bin
, addr
)) {
1529 * Addresses in ELF and DWARF are relative to base address for
1530 * PIC, so make the address argument relative too if needed.
1533 addr
-= bin
->low_addr
;
1536 cu
= bt_dwarf_cu_create(bin
->dwarf_info
);
1541 while (bt_dwarf_cu_next(cu
) == 0) {
1544 ret
= bin_info_lookup_cu_src_loc(cu
, addr
, &_src_loc
);
1554 bt_dwarf_cu_destroy(cu
);
1556 *src_loc
= _src_loc
;
1562 source_location_destroy(_src_loc
);
1563 bt_dwarf_cu_destroy(cu
);