2 * SPDX-License-Identifier: MIT
4 * Babeltrace - Executable and Shared Object Debug Info Reader
6 * Copyright 2015 Antoine Busque <abusque@efficios.com>
9 #define BT_COMP_LOG_SELF_COMP (bin->self_comp)
10 #define BT_LOG_OUTPUT_LEVEL (bin->log_level)
11 #define BT_LOG_TAG "PLUGIN/FLT.LTTNG-UTILS.DEBUG-INFO/BIN-INFO"
12 #include "logging/comp-logging.h"
28 #include "common/common.h"
36 * An address printed in hex is at most 20 bytes (16 for 64-bits +
37 * leading 0x + optional leading '+' if addr is an offset + null
40 #define ADDR_STR_LEN 20
41 #define BUILD_ID_NOTE_NAME "GNU"
43 int bin_info_init(bt_logging_level log_level
, bt_self_component
*self_comp
)
47 if (elf_version(EV_CURRENT
) == EV_NONE
) {
48 BT_COMP_LOG_CUR_LVL(BT_LOG_INFO
, log_level
, self_comp
,
49 "ELF library initialization failed: %s.",
57 struct bin_info
*bin_info_create(struct bt_fd_cache
*fdc
, const char *path
,
58 uint64_t low_addr
, uint64_t memsz
, bool is_pic
,
59 const char *debug_info_dir
, const char *target_prefix
,
60 bt_logging_level log_level
, bt_self_component
*self_comp
)
62 struct bin_info
*bin
= NULL
;
70 bin
= g_new0(struct bin_info
, 1);
75 bin
->log_level
= log_level
;
76 bin
->self_comp
= self_comp
;
78 bin
->elf_path
= g_build_filename(target_prefix
, path
, NULL
);
80 bin
->elf_path
= g_strdup(path
);
88 bin
->debug_info_dir
= g_strdup(debug_info_dir
);
89 if (!bin
->debug_info_dir
) {
96 bin
->low_addr
= low_addr
;
97 bin
->high_addr
= bin
->low_addr
+ bin
->memsz
;
99 bin
->build_id_len
= 0;
100 bin
->file_build_id_matches
= false;
106 bin_info_destroy(bin
);
110 void bin_info_destroy(struct bin_info
*bin
)
116 dwarf_end(bin
->dwarf_info
);
118 g_free(bin
->debug_info_dir
);
119 g_free(bin
->elf_path
);
120 g_free(bin
->dwarf_path
);
121 g_free(bin
->build_id
);
122 g_free(bin
->dbg_link_filename
);
124 elf_end(bin
->elf_file
);
126 bt_fd_cache_put_handle(bin
->fd_cache
, bin
->elf_handle
);
127 bt_fd_cache_put_handle(bin
->fd_cache
, bin
->dwarf_handle
);
133 * Initialize the ELF file for a given executable.
135 * @param bin bin_info instance
136 * @returns 0 on success, negative value on error.
139 int bin_info_set_elf_file(struct bin_info
*bin
)
141 struct bt_fd_cache_handle
*elf_handle
= NULL
;
142 Elf
*elf_file
= NULL
;
147 elf_handle
= bt_fd_cache_get_handle(bin
->fd_cache
, bin
->elf_path
);
149 BT_COMP_LOGI("Failed to open %s", bin
->elf_path
);
152 bin
->elf_handle
= elf_handle
;
154 elf_file
= elf_begin(bt_fd_cache_handle_get_fd(bin
->elf_handle
),
157 BT_COMP_LOGE_APPEND_CAUSE(bin
->self_comp
,
158 "elf_begin failed: %s", elf_errmsg(-1));
162 bin
->elf_file
= elf_file
;
164 if (elf_kind(elf_file
) != ELF_K_ELF
) {
165 BT_COMP_LOGE_APPEND_CAUSE(bin
->self_comp
,
166 "Error: %s is not an ELF object", bin
->elf_path
);
175 bt_fd_cache_put_handle(bin
->fd_cache
, elf_handle
);
184 * From a note section data struct, check if it is a build id note.
186 * @param note_data Pointer to a note section
188 * @returns 1 on match, 0 if `buf` does not contain a
189 * valid build id note
192 int is_build_id_note_section(Elf_Data
*note_data
)
194 size_t name_offset
, desc_offset
;
195 GElf_Nhdr note_header
;
199 * Discard the return value as it contains the size of the note section
200 * and we don't need it.
202 (void) gelf_getnote(note_data
, 0, ¬e_header
, &name_offset
,
206 * Check the note name length. The name_sz field includes the
207 * terminating null byte.
209 if (note_header
.n_namesz
!= sizeof(BUILD_ID_NOTE_NAME
)) {
213 /* Check the note type. */
214 if (note_header
.n_type
!= NT_GNU_BUILD_ID
) {
218 /* Check the note name. */
219 if (memcmp(note_data
->d_buf
+ name_offset
, BUILD_ID_NOTE_NAME
,
220 note_header
.n_namesz
) != 0) {
231 * From a build id note section data struct, check if the build id it contains
232 * is identical to the build id passed as parameter.
234 * @param note_data Pointer to the file build id note section.
235 * @param build_id Pointer to a build id to compare to.
236 * @param build_id_len length of the build id.
238 * @returns 1 on match, 0 otherwise.
241 int is_build_id_note_section_matching(Elf_Data
*note_data
,
242 uint8_t *build_id
, size_t build_id_len
)
244 size_t name_offset
, desc_offset
;
245 GElf_Nhdr note_header
;
247 if (build_id_len
<= 0) {
252 * Discard the return value as it contains the size of the note section
253 * and we don't need it.
255 (void) gelf_getnote(note_data
, 0, ¬e_header
, &name_offset
,
259 * Compare the binary build id with the supplied build id.
261 if (memcmp(build_id
, note_data
->d_buf
+ desc_offset
,
262 build_id_len
) == 0) {
270 * Checks if the build id stored in `bin` (bin->build_id) is matching the build
271 * id of the ondisk file (bin->elf_file).
273 * @param bin bin_info instance
274 * @param build_id build id to compare ot the on disk file
275 * @param build_id_len length of the build id
277 * @returns 1 on if the build id of stored in `bin` matches
278 * the build id of the ondisk file.
279 * 0 on if they are different or an error occurred.
282 int is_build_id_matching(struct bin_info
*bin
)
284 int ret
, is_build_id
, is_matching
= 0;
285 Elf_Scn
*curr_section
= NULL
, *next_section
= NULL
;
286 GElf_Shdr curr_section_hdr
;
288 if (!bin
->build_id
) {
292 /* Set ELF file if it hasn't been accessed yet. */
293 if (!bin
->elf_file
) {
294 ret
= bin_info_set_elf_file(bin
);
296 /* Failed to set ELF file. */
301 next_section
= elf_nextscn(bin
->elf_file
, curr_section
);
306 while (next_section
) {
307 Elf_Data
*note_data
= NULL
;
309 curr_section
= next_section
;
310 next_section
= elf_nextscn(bin
->elf_file
, curr_section
);
312 if (!gelf_getshdr(curr_section
, &curr_section_hdr
)) {
316 if (curr_section_hdr
.sh_type
!= SHT_NOTE
) {
321 * elf_getdata() translates the data to native byte order.
323 note_data
= elf_getdata(curr_section
, NULL
);
328 /* Check if the note is of the build-id type. */
329 is_build_id
= is_build_id_note_section(note_data
);
335 * Compare the build id of the on-disk file and
336 * the build id recorded in the trace.
338 is_matching
= is_build_id_note_section_matching(
339 note_data
, bin
->build_id
, bin
->build_id_len
);
348 int bin_info_set_build_id(struct bin_info
*bin
, uint8_t *build_id
,
351 if (!bin
|| !build_id
) {
355 /* Free any previously set build id. */
356 g_free(bin
->build_id
);
358 /* Set the build id. */
359 bin
->build_id
= g_new0(uint8_t, build_id_len
);
360 if (!bin
->build_id
) {
364 memcpy(bin
->build_id
, build_id
, build_id_len
);
365 bin
->build_id_len
= build_id_len
;
368 * Check if the file found on the file system has the same build id
369 * that what was recorded in the trace.
371 bin
->file_build_id_matches
= is_build_id_matching(bin
);
372 if (!bin
->file_build_id_matches
) {
373 BT_COMP_LOGI_STR("Supplied Build ID does not match Build ID of the "
374 "binary or library found on the file system.");
379 * Reset the is_elf_only flag in case it had been set
380 * previously, because we might find separate debug info using
381 * the new build id information.
383 bin
->is_elf_only
= false;
391 int bin_info_set_debug_link(struct bin_info
*bin
, const char *filename
,
394 if (!bin
|| !filename
) {
398 bin
->dbg_link_filename
= g_strdup(filename
);
399 if (!bin
->dbg_link_filename
) {
403 bin
->dbg_link_crc
= crc
;
406 * Reset the is_elf_only flag in case it had been set
407 * previously, because we might find separate debug info using
408 * the new build id information.
410 bin
->is_elf_only
= false;
420 * Tries to read DWARF info from the location given by path, and
421 * attach it to the given bin_info instance if it exists.
423 * @param bin bin_info instance for which to set DWARF info
424 * @param path Presumed location of the DWARF info
425 * @returns 0 on success, negative value on failure
428 int bin_info_set_dwarf_info_from_path(struct bin_info
*bin
, char *path
)
431 struct bt_fd_cache_handle
*dwarf_handle
= NULL
;
432 struct bt_dwarf_cu
*cu
= NULL
;
433 Dwarf
*dwarf_info
= NULL
;
439 dwarf_handle
= bt_fd_cache_get_handle(bin
->fd_cache
, path
);
444 dwarf_info
= dwarf_begin(bt_fd_cache_handle_get_fd(dwarf_handle
),
451 * Check if the dwarf info has any CU. If not, the
452 * executable's object file contains no DWARF info.
454 cu
= bt_dwarf_cu_create(dwarf_info
);
459 ret
= bt_dwarf_cu_next(cu
);
464 bin
->dwarf_handle
= dwarf_handle
;
465 bin
->dwarf_path
= g_strdup(path
);
466 if (!bin
->dwarf_path
) {
469 bin
->dwarf_info
= dwarf_info
;
476 bt_fd_cache_put_handle(bin
->fd_cache
, dwarf_handle
);
478 dwarf_end(dwarf_info
);
486 * Try to set the dwarf_info for a given bin_info instance via the
489 * @param bin bin_info instance for which to retrieve the
490 * DWARF info via build ID
491 * @returns 0 on success (i.e. dwarf_info set), -1 on failure
494 int bin_info_set_dwarf_info_build_id(struct bin_info
*bin
)
497 char *path
= NULL
, *build_id_prefix_dir
= NULL
, *build_id_file
= NULL
;
498 const char *dbg_dir
= NULL
;
499 size_t build_id_char_len
, build_id_suffix_char_len
, build_id_file_len
;
501 if (!bin
|| !bin
->build_id
) {
505 dbg_dir
= bin
->debug_info_dir
? bin
->debug_info_dir
: DEFAULT_DEBUG_DIR
;
508 * The prefix dir is the first byte of the build id, represented in
509 * lowercase hex as two characters per byte, +1 for '\0'.
511 build_id_prefix_dir
= g_new0(gchar
, BUILD_ID_PREFIX_DIR_LEN
+ 1);
512 if (!build_id_prefix_dir
) {
515 g_snprintf(build_id_prefix_dir
, BUILD_ID_PREFIX_DIR_LEN
+ 1, "%02x", bin
->build_id
[0]);
518 * The build id file is the remaining bytes of the build id,
519 * represented in lowercase hex, as two characters per byte.
521 build_id_char_len
= (2 * (bin
->build_id_len
- 1));
523 /* To which the build id suffix is added, +1 for '\0'. */
524 build_id_suffix_char_len
= strlen(BUILD_ID_SUFFIX
) + 1;
527 * The resulting filename string is the concatenation of the
528 * hex build id and the suffix.
530 build_id_file_len
= build_id_char_len
+ build_id_suffix_char_len
;
531 build_id_file
= g_new0(gchar
, build_id_file_len
);
532 if (!build_id_file
) {
537 * For each byte, starting at offset 1, append two characters
540 for (i
= 1; i
< bin
->build_id_len
; ++i
) {
541 int path_idx
= 2 * (i
- 1);
543 g_snprintf(&build_id_file
[path_idx
], 3, "%02x", bin
->build_id
[i
]);
545 /* Append the suffix to the generated string, including the '\0'. */
546 g_snprintf(&build_id_file
[build_id_char_len
], build_id_suffix_char_len
,
549 path
= g_build_filename(dbg_dir
, BUILD_ID_SUBDIR
, build_id_prefix_dir
, build_id_file
, NULL
);
554 ret
= bin_info_set_dwarf_info_from_path(bin
, path
);
564 g_free(build_id_prefix_dir
);
565 g_free(build_id_file
);
572 * Tests whether the file located at path exists and has the expected
575 * This predicate is used when looking up separate debug info via the
576 * GNU debuglink method. The expected crc can be found .gnu_debuglink
577 * section in the original ELF file, along with the filename for the
578 * file containing the debug info.
580 * @param path Full path at which to look for the debug file
581 * @param crc Expected checksum for the debug file
582 * @returns 1 if the file exists and has the correct checksum,
586 int is_valid_debug_file(struct bin_info
*bin
, char *path
, uint32_t crc
)
589 struct bt_fd_cache_handle
*debug_handle
= NULL
;
596 debug_handle
= bt_fd_cache_get_handle(bin
->fd_cache
, path
);
601 ret
= crc32(bt_fd_cache_handle_get_fd(debug_handle
), &_crc
);
610 bt_fd_cache_put_handle(bin
->fd_cache
, debug_handle
);
615 * Try to set the dwarf_info for a given bin_info instance via the
618 * @param bin bin_info instance for which to retrieve the
619 * DWARF info via debug link
620 * @returns 0 on success (i.e. dwarf_info set), -1 on failure
623 int bin_info_set_dwarf_info_debug_link(struct bin_info
*bin
)
626 const gchar
*dbg_dir
= NULL
;
627 gchar
*bin_dir
= NULL
, *path
= NULL
;
629 if (!bin
|| !bin
->dbg_link_filename
) {
633 dbg_dir
= bin
->debug_info_dir
? bin
->debug_info_dir
: DEFAULT_DEBUG_DIR
;
634 bin_dir
= g_path_get_dirname(bin
->elf_path
);
636 /* First look in the executable's dir */
637 path
= g_build_filename(bin_dir
, bin
->dbg_link_filename
, NULL
);
639 if (is_valid_debug_file(bin
, path
, bin
->dbg_link_crc
)) {
643 /* If not found, look in .debug subdir */
645 path
= g_build_filename(bin_dir
, DEBUG_SUBDIR
, bin
->dbg_link_filename
, NULL
);
647 if (is_valid_debug_file(bin
, path
, bin
->dbg_link_crc
)) {
651 /* Lastly, look under the global debug directory */
654 path
= g_build_filename(dbg_dir
, bin_dir
, bin
->dbg_link_filename
, NULL
);
655 if (is_valid_debug_file(bin
, path
, bin
->dbg_link_crc
)) {
668 ret
= bin_info_set_dwarf_info_from_path(bin
, path
);
677 * Initialize the DWARF info for a given executable.
679 * @param bin bin_info instance
680 * @returns 0 on success, negative value on failure
683 int bin_info_set_dwarf_info(struct bin_info
*bin
)
692 /* First try to set the DWARF info from the ELF file */
693 ret
= bin_info_set_dwarf_info_from_path(bin
, bin
->elf_path
);
699 * If that fails, try to find separate debug info via build ID
702 ret
= bin_info_set_dwarf_info_build_id(bin
);
707 ret
= bin_info_set_dwarf_info_debug_link(bin
);
716 void source_location_destroy(struct source_location
*src_loc
)
722 free(src_loc
->filename
);
727 * Append a string representation of an address offset to an existing
730 * On success, the out parameter `result` will contain the base string
731 * followed by the offset string of the form "+0x1234". On failure,
732 * `result` remains unchanged.
734 * @param base_str The string to which to append an offset string
735 * @param low_addr The lower virtual memory address, the base from
736 * which the offset is computed
737 * @param high_addr The higher virtual memory address
738 * @param result Out parameter, the base string followed by the
740 * @returns 0 on success, -1 on failure
743 int bin_info_append_offset_str(const char *base_str
, uint64_t low_addr
,
744 uint64_t high_addr
, char **result
)
747 char *_result
= NULL
;
749 if (!base_str
|| !result
) {
753 offset
= high_addr
- low_addr
;
755 _result
= g_strdup_printf("%s+%#0" PRIx64
, base_str
, offset
);
769 * Try to find the symbol closest to an address within a given ELF
772 * Only function symbols are taken into account. The symbol's address
773 * must precede `addr`. A symbol with a closer address might exist
774 * after `addr` but is irrelevant because it cannot encompass `addr`.
776 * On success, if found, the out parameters `sym` and `shdr` are
777 * set. On failure or if none are found, they remain unchanged.
779 * @param scn ELF section in which to look for the address
780 * @param addr Virtual memory address for which to find the
781 * nearest function symbol
782 * @param sym Out parameter, the nearest function symbol
783 * @param shdr Out parameter, the section header for scn
784 * @returns 0 on success, -1 on failure
787 int bin_info_get_nearest_symbol_from_section(Elf_Scn
*scn
, uint64_t addr
,
788 GElf_Sym
**sym
, GElf_Shdr
**shdr
)
792 Elf_Data
*data
= NULL
;
793 GElf_Shdr
*_shdr
= NULL
;
794 GElf_Sym
*nearest_sym
= NULL
;
796 if (!scn
|| !sym
|| !shdr
) {
800 _shdr
= g_new0(GElf_Shdr
, 1);
805 _shdr
= gelf_getshdr(scn
, _shdr
);
810 if (_shdr
->sh_type
!= SHT_SYMTAB
) {
812 * We are only interested in symbol table (symtab)
813 * sections, skip this one.
818 data
= elf_getdata(scn
, NULL
);
823 symbol_count
= _shdr
->sh_size
/ _shdr
->sh_entsize
;
825 for (i
= 0; i
< symbol_count
; ++i
) {
826 GElf_Sym
*cur_sym
= NULL
;
828 cur_sym
= g_new0(GElf_Sym
, 1);
832 cur_sym
= gelf_getsym(data
, i
, cur_sym
);
836 if (GELF_ST_TYPE(cur_sym
->st_info
) != STT_FUNC
) {
837 /* We're only interested in the functions. */
842 if (cur_sym
->st_value
<= addr
&&
844 cur_sym
->st_value
> nearest_sym
->st_value
)) {
846 nearest_sym
= cur_sym
;
869 * Get the name of the function containing a given address within an
870 * executable using ELF symbols.
872 * The function name is in fact the name of the nearest ELF symbol,
873 * followed by the offset in bytes between the address and the symbol
874 * (in hex), separated by a '+' character.
876 * If found, the out parameter `func_name` is set on success. On failure,
877 * it remains unchanged.
879 * @param bin bin_info instance for the executable containing
881 * @param addr Virtual memory address for which to find the
883 * @param func_name Out parameter, the function name
884 * @returns 0 on success, -1 on failure
887 int bin_info_lookup_elf_function_name(struct bin_info
*bin
, uint64_t addr
,
891 * TODO (possible optimisation): if an ELF has no symtab
892 * section, it has been stripped. Therefore, it would be wise
893 * to store a flag indicating the stripped status after the
894 * first iteration to prevent subsequent ones.
898 GElf_Sym
*sym
= NULL
;
899 GElf_Shdr
*shdr
= NULL
;
900 char *sym_name
= NULL
;
902 /* Set ELF file if it hasn't been accessed yet. */
903 if (!bin
->elf_file
) {
904 ret
= bin_info_set_elf_file(bin
);
906 /* Failed to set ELF file. */
911 scn
= elf_nextscn(bin
->elf_file
, scn
);
916 while (scn
&& !sym
) {
917 ret
= bin_info_get_nearest_symbol_from_section(
918 scn
, addr
, &sym
, &shdr
);
923 scn
= elf_nextscn(bin
->elf_file
, scn
);
927 sym_name
= elf_strptr(bin
->elf_file
, shdr
->sh_link
,
933 ret
= bin_info_append_offset_str(sym_name
, sym
->st_value
, addr
,
951 * Get the name of the function containing a given address within a
952 * given compile unit (CU).
954 * If found, the out parameter `func_name` is set on success. On
955 * failure, it remains unchanged.
957 * @param cu bt_dwarf_cu instance which may contain the address
958 * @param addr Virtual memory address for which to find the
960 * @param func_name Out parameter, the function name
961 * @returns 0 on success, -1 on failure
964 int bin_info_lookup_cu_function_name(struct bt_dwarf_cu
*cu
, uint64_t addr
,
969 struct bt_dwarf_die
*die
= NULL
;
971 if (!cu
|| !func_name
) {
975 die
= bt_dwarf_die_create(cu
);
980 while (bt_dwarf_die_next(die
) == 0) {
983 ret
= bt_dwarf_die_get_tag(die
, &tag
);
988 if (tag
== DW_TAG_subprogram
) {
989 ret
= bt_dwarf_die_contains_addr(die
, addr
, &found
);
1001 uint64_t low_addr
= 0;
1002 char *die_name
= NULL
;
1004 ret
= bt_dwarf_die_get_name(die
, &die_name
);
1009 ret
= dwarf_lowpc(die
->dwarf_die
, &low_addr
);
1015 ret
= bin_info_append_offset_str(die_name
, low_addr
, addr
,
1023 bt_dwarf_die_destroy(die
);
1027 bt_dwarf_die_destroy(die
);
1032 * Get the name of the function containing a given address within an
1033 * executable using DWARF debug info.
1035 * If found, the out parameter `func_name` is set on success. On
1036 * failure, it remains unchanged.
1038 * @param bin bin_info instance for the executable containing
1040 * @param addr Virtual memory address for which to find the
1042 * @param func_name Out parameter, the function name
1043 * @returns 0 on success, -1 on failure
1046 int bin_info_lookup_dwarf_function_name(struct bin_info
*bin
, uint64_t addr
,
1050 char *_func_name
= NULL
;
1051 struct bt_dwarf_cu
*cu
= NULL
;
1053 if (!bin
|| !func_name
) {
1057 cu
= bt_dwarf_cu_create(bin
->dwarf_info
);
1062 while (bt_dwarf_cu_next(cu
) == 0) {
1063 ret
= bin_info_lookup_cu_function_name(cu
, addr
, &_func_name
);
1074 *func_name
= _func_name
;
1079 bt_dwarf_cu_destroy(cu
);
1083 bt_dwarf_cu_destroy(cu
);
1087 int bin_info_lookup_function_name(struct bin_info
*bin
,
1088 uint64_t addr
, char **func_name
)
1091 char *_func_name
= NULL
;
1093 if (!bin
|| !func_name
) {
1098 * If the bin_info has a build id but it does not match the build id
1099 * that was found on the file system, return an error.
1101 if (bin
->build_id
&& !bin
->file_build_id_matches
) {
1105 /* Set DWARF info if it hasn't been accessed yet. */
1106 if (!bin
->dwarf_info
&& !bin
->is_elf_only
) {
1107 ret
= bin_info_set_dwarf_info(bin
);
1109 BT_COMP_LOGI_STR("Failed to set bin dwarf info, falling "
1110 "back to ELF lookup.");
1111 /* Failed to set DWARF info, fallback to ELF. */
1112 bin
->is_elf_only
= true;
1116 if (!bin_info_has_address(bin
, addr
)) {
1121 * Addresses in ELF and DWARF are relative to base address for
1122 * PIC, so make the address argument relative too if needed.
1125 addr
-= bin
->low_addr
;
1128 if (bin
->is_elf_only
) {
1129 ret
= bin_info_lookup_elf_function_name(bin
, addr
,
1132 BT_COMP_LOGI("Failed to lookup function name (ELF): "
1136 ret
= bin_info_lookup_dwarf_function_name(bin
, addr
,
1139 BT_COMP_LOGI("Failed to lookup function name (DWARF): "
1144 *func_name
= _func_name
;
1151 int bin_info_get_bin_loc(struct bin_info
*bin
, uint64_t addr
, char **bin_loc
)
1153 gchar
*_bin_loc
= NULL
;
1155 if (!bin
|| !bin_loc
) {
1160 * If the bin_info has a build id but it does not match the build id
1161 * that was found on the file system, return an error.
1163 if (bin
->build_id
&& !bin
->file_build_id_matches
) {
1168 addr
-= bin
->low_addr
;
1169 _bin_loc
= g_strdup_printf("+%#0" PRIx64
, addr
);
1171 _bin_loc
= g_strdup_printf("@%#0" PRIx64
, addr
);
1178 *bin_loc
= _bin_loc
;
1186 * Predicate used to determine whether the children of a given DIE
1187 * contain a specific address.
1189 * More specifically, the parameter `die` is expected to be a
1190 * subprogram (function) DIE, and this predicate tells whether any
1191 * subroutines are inlined within this function and would contain
1194 * On success, the out parameter `contains` is set with the boolean
1195 * value indicating whether the DIE's range covers `addr`. On failure,
1196 * it remains unchanged.
1198 * Do note that this function advances the position of `die`. If the
1199 * address is found within one of its children, `die` will be pointing
1200 * to that child upon returning from the function, allowing to extract
1201 * the information deemed necessary.
1203 * @param die The parent DIE in whose children the address will be
1205 * @param addr The address for which to look for in the DIEs
1206 * @param contains Out parameter, true if addr is contained,
1208 * @returns Returns 0 on success, -1 on failure
1211 int bin_info_child_die_has_address(struct bt_dwarf_die
*die
, uint64_t addr
, bool *contains
)
1214 bool _contains
= false;
1220 ret
= bt_dwarf_die_child(die
);
1226 ret
= bt_dwarf_die_contains_addr(die
, addr
, &_contains
);
1233 * The address is within the range of the current DIE
1238 ret
= bt_dwarf_die_get_tag(die
, &tag
);
1243 if (tag
== DW_TAG_inlined_subroutine
) {
1244 /* Found the tracepoint. */
1248 if (bt_dwarf_die_has_children(die
)) {
1250 * Look for the address in the children DIEs.
1252 ret
= bt_dwarf_die_child(die
);
1258 } while (bt_dwarf_die_next(die
) == 0);
1261 *contains
= _contains
;
1269 * Lookup the source location for a given address within a CU, making
1270 * the assumption that it is contained within an inline routine in a
1273 * @param cu bt_dwarf_cu instance in which to look for the address
1274 * @param addr The address for which to look for
1275 * @param src_loc Out parameter, the source location (filename and
1276 * line number) for the address
1277 * @returns 0 on success, -1 on failure
1280 int bin_info_lookup_cu_src_loc_inl(struct bt_dwarf_cu
*cu
, uint64_t addr
,
1281 struct source_location
**src_loc
)
1285 struct bt_dwarf_die
*die
= NULL
;
1286 struct source_location
*_src_loc
= NULL
;
1288 if (!cu
|| !src_loc
) {
1292 die
= bt_dwarf_die_create(cu
);
1297 while (bt_dwarf_die_next(die
) == 0) {
1300 ret
= bt_dwarf_die_get_tag(die
, &tag
);
1305 if (tag
== DW_TAG_subprogram
) {
1306 bool contains
= false;
1308 ret
= bt_dwarf_die_contains_addr(die
, addr
, &contains
);
1315 * Try to find an inlined subroutine
1316 * child of this DIE containing addr.
1318 ret
= bin_info_child_die_has_address(die
, addr
,
1331 char *filename
= NULL
;
1334 _src_loc
= g_new0(struct source_location
, 1);
1339 ret
= bt_dwarf_die_get_call_file(die
, &filename
);
1343 ret
= bt_dwarf_die_get_call_line(die
, &line_no
);
1349 _src_loc
->filename
= filename
;
1350 _src_loc
->line_no
= line_no
;
1351 *src_loc
= _src_loc
;
1354 bt_dwarf_die_destroy(die
);
1358 source_location_destroy(_src_loc
);
1359 bt_dwarf_die_destroy(die
);
1364 * Lookup the source location for a given address within a CU,
1365 * assuming that it is contained within an inlined function.
1367 * A source location can be found regardless of inlining status for
1368 * this method, but in the case of an inlined function, the returned
1369 * source location will point not to the callsite but rather to the
1370 * definition site of the inline function.
1372 * @param cu bt_dwarf_cu instance in which to look for the address
1373 * @param addr The address for which to look for
1374 * @param src_loc Out parameter, the source location (filename and
1375 * line number) for the address. Set only if the address
1376 * is found and resolved successfully
1378 * @returns 0 on success, -1 on failure
1381 int bin_info_lookup_cu_src_loc_no_inl(struct bt_dwarf_cu
*cu
, uint64_t addr
,
1382 struct source_location
**src_loc
)
1384 struct source_location
*_src_loc
= NULL
;
1385 struct bt_dwarf_die
*die
= NULL
;
1386 const char *filename
= NULL
;
1387 Dwarf_Line
*line
= NULL
;
1388 Dwarf_Addr line_addr
;
1389 int ret
= 0, line_no
;
1391 if (!cu
|| !src_loc
) {
1395 die
= bt_dwarf_die_create(cu
);
1400 line
= dwarf_getsrc_die(die
->dwarf_die
, addr
);
1402 /* This is not an error. The caller needs to keep looking. */
1406 ret
= dwarf_lineaddr(line
, &line_addr
);
1411 filename
= dwarf_linesrc(line
, NULL
, NULL
);
1416 if (addr
== line_addr
) {
1417 _src_loc
= g_new0(struct source_location
, 1);
1422 ret
= dwarf_lineno(line
, &line_no
);
1427 _src_loc
->line_no
= line_no
;
1428 _src_loc
->filename
= g_strdup(filename
);
1432 *src_loc
= _src_loc
;
1438 source_location_destroy(_src_loc
);
1441 bt_dwarf_die_destroy(die
);
1446 * Get the source location (file name and line number) for a given
1447 * address within a compile unit (CU).
1449 * On success, the out parameter `src_loc` is set if found. On
1450 * failure, it remains unchanged.
1452 * @param cu bt_dwarf_cu instance for the compile unit which
1453 * may contain the address
1454 * @param addr Virtual memory address for which to find the
1456 * @param src_loc Out parameter, the source location
1457 * @returns 0 on success, -1 on failure
1460 int bin_info_lookup_cu_src_loc(struct bt_dwarf_cu
*cu
, uint64_t addr
,
1461 struct source_location
**src_loc
)
1464 struct source_location
*_src_loc
= NULL
;
1466 if (!cu
|| !src_loc
) {
1470 ret
= bin_info_lookup_cu_src_loc_inl(cu
, addr
, &_src_loc
);
1479 ret
= bin_info_lookup_cu_src_loc_no_inl(cu
, addr
, &_src_loc
);
1490 *src_loc
= _src_loc
;
1496 source_location_destroy(_src_loc
);
1500 int bin_info_lookup_source_location(struct bin_info
*bin
, uint64_t addr
,
1501 struct source_location
**src_loc
)
1503 struct bt_dwarf_cu
*cu
= NULL
;
1504 struct source_location
*_src_loc
= NULL
;
1506 if (!bin
|| !src_loc
) {
1511 * If the bin_info has a build id but it does not match the build id
1512 * that was found on the file system, return an error.
1514 if (bin
->build_id
&& !bin
->file_build_id_matches
) {
1518 /* Set DWARF info if it hasn't been accessed yet. */
1519 if (!bin
->dwarf_info
&& !bin
->is_elf_only
) {
1520 if (bin_info_set_dwarf_info(bin
)) {
1521 /* Failed to set DWARF info. */
1522 bin
->is_elf_only
= true;
1526 if (bin
->is_elf_only
) {
1527 /* We cannot lookup source location without DWARF info. */
1531 if (!bin_info_has_address(bin
, addr
)) {
1536 * Addresses in ELF and DWARF are relative to base address for
1537 * PIC, so make the address argument relative too if needed.
1540 addr
-= bin
->low_addr
;
1543 cu
= bt_dwarf_cu_create(bin
->dwarf_info
);
1548 while (bt_dwarf_cu_next(cu
) == 0) {
1551 ret
= bin_info_lookup_cu_src_loc(cu
, addr
, &_src_loc
);
1561 bt_dwarf_cu_destroy(cu
);
1563 *src_loc
= _src_loc
;
1569 source_location_destroy(_src_loc
);
1570 bt_dwarf_cu_destroy(cu
);