-/*
- * bin-info.c
- *
- * Babeltrace - Executable and Shared Object Debug Info Reader
- *
- * Copyright 2015 Antoine Busque <abusque@efficios.com>
- *
- * Author: Antoine Busque <abusque@efficios.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
- */
-
-#include <fcntl.h>
-#include <math.h>
-#include <libgen.h>
-#include <stdio.h>
-#include <inttypes.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <dwarf.h>
-#include <glib.h>
-#include <babeltrace/dwarf.h>
-#include <babeltrace/bin-info.h>
-#include <babeltrace/crc32.h>
-#include <babeltrace/babeltrace-internal.h>
-#include <babeltrace/utils.h>
-#include <errno.h>
-
-/*
- * An address printed in hex is at most 20 bytes (16 for 64-bits +
- * leading 0x + optional leading '+' if addr is an offset + null
- * character).
- */
-#define ADDR_STR_LEN 20
-
-BT_HIDDEN
-int bin_info_init(void)
-{
- int ret = 0;
-
- if (elf_version(EV_CURRENT) == EV_NONE) {
- printf_debug("ELF library initialization failed: %s\n",
- elf_errmsg(-1));
- ret = -1;
- }
-
- return ret;
-}
-
-BT_HIDDEN
-struct bin_info *bin_info_create(const char *path, uint64_t low_addr,
- uint64_t memsz, bool is_pic)
-{
- struct bin_info *bin = NULL;
-
- if (!path) {
- goto error;
- }
-
- bin = g_new0(struct bin_info, 1);
- if (!bin) {
- goto error;
- }
-
- if (opt_debug_info_target_prefix) {
- bin->elf_path = g_build_path("/", opt_debug_info_target_prefix,
- path, NULL);
- } else {
- bin->elf_path = strdup(path);
- }
-
- if (!bin->elf_path) {
- goto error;
- }
-
- bin->is_pic = is_pic;
- bin->memsz = memsz;
- bin->low_addr = low_addr;
- bin->high_addr = bin->low_addr + bin->memsz;
-
- return bin;
-
-error:
- bin_info_destroy(bin);
- return NULL;
-}
-
-BT_HIDDEN
-void bin_info_destroy(struct bin_info *bin)
-{
- if (!bin) {
- return;
- }
-
- dwarf_end(bin->dwarf_info);
-
- free(bin->elf_path);
- free(bin->dwarf_path);
- free(bin->build_id);
- free(bin->dbg_link_filename);
-
- elf_end(bin->elf_file);
-
- close(bin->elf_fd);
- close(bin->dwarf_fd);
-
- g_free(bin);
-}
-
-
-BT_HIDDEN
-int bin_info_set_build_id(struct bin_info *bin, uint8_t *build_id,
- size_t build_id_len)
-{
- if (!bin || !build_id) {
- goto error;
- }
-
- bin->build_id = malloc(build_id_len);
- if (!bin->build_id) {
- goto error;
- }
-
- memcpy(bin->build_id, build_id, build_id_len);
- bin->build_id_len = build_id_len;
-
- /*
- * Reset the is_elf_only flag in case it had been set
- * previously, because we might find separate debug info using
- * the new build id information.
- */
- bin->is_elf_only = false;
-
- return 0;
-
-error:
-
- return -1;
-}
-
-BT_HIDDEN
-int bin_info_set_debug_link(struct bin_info *bin, char *filename, uint32_t crc)
-{
- if (!bin || !filename) {
- goto error;
- }
-
- bin->dbg_link_filename = strdup(filename);
- if (!bin->dbg_link_filename) {
- goto error;
- }
-
- bin->dbg_link_crc = crc;
-
- /*
- * Reset the is_elf_only flag in case it had been set
- * previously, because we might find separate debug info using
- * the new build id information.
- */
- bin->is_elf_only = false;
-
- return 0;
-
-error:
-
- return -1;
-}
-
-/**
- * Tries to read DWARF info from the location given by path, and
- * attach it to the given bin_info instance if it exists.
- *
- * @param bin bin_info instance for which to set DWARF info
- * @param path Presumed location of the DWARF info
- * @returns 0 on success, negative value on failure
- */
-static
-int bin_info_set_dwarf_info_from_path(struct bin_info *bin, char *path)
-{
- int fd = -1, ret = 0;
- struct bt_dwarf_cu *cu = NULL;
- Dwarf *dwarf_info = NULL;
-
- if (!bin || !path) {
- goto error;
- }
-
- fd = open(path, O_RDONLY);
- if (fd < 0) {
- fd = -errno;
- goto error;
- }
-
- dwarf_info = dwarf_begin(fd, DWARF_C_READ);
- if (!dwarf_info) {
- goto error;
- }
-
- /*
- * Check if the dwarf info has any CU. If not, the
- * executable's object file contains no DWARF info.
- */
- cu = bt_dwarf_cu_create(dwarf_info);
- if (!cu) {
- goto error;
- }
-
- ret = bt_dwarf_cu_next(cu);
- if (ret) {
- goto error;
- }
-
- bin->dwarf_fd = fd;
- bin->dwarf_path = strdup(path);
- if (!bin->dwarf_path) {
- goto error;
- }
- bin->dwarf_info = dwarf_info;
- free(cu);
-
- return 0;
-
-error:
- if (fd >= 0) {
- close(fd);
- fd = -1;
- }
- dwarf_end(dwarf_info);
- g_free(dwarf_info);
- free(cu);
-
- return fd;
-}
-
-/**
- * Try to set the dwarf_info for a given bin_info instance via the
- * build ID method.
- *
- * @param bin bin_info instance for which to retrieve the
- * DWARF info via build ID
- * @returns 0 on success (i.e. dwarf_info set), -1 on failure
- */
-static
-int bin_info_set_dwarf_info_build_id(struct bin_info *bin)
-{
- int i = 0, ret = 0;
- char *path = NULL, *build_id_file = NULL;
- const char *dbg_dir = NULL;
- size_t build_id_file_len;
-
- if (!bin || !bin->build_id) {
- goto error;
- }
-
- dbg_dir = opt_debug_info_dir ? : DEFAULT_DEBUG_DIR;
-
- /* 2 characters per byte printed in hex, +1 for '/' and +1 for '\0' */
- build_id_file_len = (2 * bin->build_id_len) + 1 +
- strlen(BUILD_ID_SUFFIX) + 1;
- build_id_file = malloc(build_id_file_len);
- if (!build_id_file) {
- goto error;
- }
-
- snprintf(build_id_file, 4, "%02x/", bin->build_id[0]);
- for (i = 1; i < bin->build_id_len; ++i) {
- int path_idx = 3 + 2 * (i - 1);
-
- snprintf(&build_id_file[path_idx], 3, "%02x", bin->build_id[i]);
- }
- strcat(build_id_file, BUILD_ID_SUFFIX);
-
- path = g_build_path("/", dbg_dir, BUILD_ID_SUBDIR, build_id_file, NULL);
- if (!path) {
- goto error;
- }
-
- ret = bin_info_set_dwarf_info_from_path(bin, path);
- if (ret) {
- goto error;
- }
-
- goto end;
-
-error:
- ret = -1;
-end:
- free(build_id_file);
- free(path);
-
- return ret;
-}
-
-/**
- * Tests whether the file located at path exists and has the expected
- * checksum.
- *
- * This predicate is used when looking up separate debug info via the
- * GNU debuglink method. The expected crc can be found .gnu_debuglink
- * section in the original ELF file, along with the filename for the
- * file containing the debug info.
- *
- * @param path Full path at which to look for the debug file
- * @param crc Expected checksum for the debug file
- * @returns 1 if the file exists and has the correct checksum,
- * 0 otherwise
- */
-static
-int is_valid_debug_file(char *path, uint32_t crc)
-{
- int ret = 0, fd = -1;
- uint32_t _crc = 0;
-
- if (!path) {
- goto end_noclose;
- }
-
- fd = open(path, O_RDONLY);
- if (fd < 0) {
- goto end_noclose;
- }
-
- ret = crc32(fd, &_crc);
- if (ret) {
- ret = 0;
- goto end;
- }
-
- ret = (crc == _crc);
-
-end:
- close(fd);
-end_noclose:
- return ret;
-}
-
-/**
- * Try to set the dwarf_info for a given bin_info instance via the
- * build ID method.
- *
- * @param bin bin_info instance for which to retrieve the
- * DWARF info via debug link
- * @returns 0 on success (i.e. dwarf_info set), -1 on failure
- */
-static
-int bin_info_set_dwarf_info_debug_link(struct bin_info *bin)
-{
- int ret = 0;
- const char *dbg_dir = NULL;
- char *dir_name = NULL, *bin_dir = NULL, *path = NULL;
- size_t max_path_len = 0;
-
- if (!bin || !bin->dbg_link_filename) {
- goto error;
- }
-
- dbg_dir = opt_debug_info_dir ? : DEFAULT_DEBUG_DIR;
-
- dir_name = dirname(bin->elf_path);
- if (!dir_name) {
- goto error;
- }
-
- /* bin_dir is just dir_name with a trailing slash */
- bin_dir = malloc(strlen(dir_name) + 2);
- if (!bin_dir) {
- goto error;
- }
-
- strcpy(bin_dir, dir_name);
- strcat(bin_dir, "/");
-
- max_path_len = strlen(dbg_dir) + strlen(bin_dir) +
- strlen(DEBUG_SUBDIR) + strlen(bin->dbg_link_filename)
- + 1;
- path = malloc(max_path_len);
- if (!path) {
- goto error;
- }
-
- /* First look in the executable's dir */
- strcpy(path, bin_dir);
- strcat(path, bin->dbg_link_filename);
-
- if (is_valid_debug_file(path, bin->dbg_link_crc)) {
- goto found;
- }
-
- /* If not found, look in .debug subdir */
- strcpy(path, bin_dir);
- strcat(path, DEBUG_SUBDIR);
- strcat(path, bin->dbg_link_filename);
-
- if (is_valid_debug_file(path, bin->dbg_link_crc)) {
- goto found;
- }
-
- /* Lastly, look under the global debug directory */
- strcpy(path, dbg_dir);
- strcat(path, bin_dir);
- strcat(path, bin->dbg_link_filename);
-
- if (is_valid_debug_file(path, bin->dbg_link_crc)) {
- goto found;
- }
-
-error:
- ret = -1;
-end:
- free(path);
- free(bin_dir);
-
- return ret;
-
-found:
- ret = bin_info_set_dwarf_info_from_path(bin, path);
- if (ret) {
- goto error;
- }
-
- goto end;
-}
-
-/**
- * Initialize the DWARF info for a given executable.
- *
- * @param bin bin_info instance
- * @returns 0 on success, negative value on failure
- */
-static
-int bin_info_set_dwarf_info(struct bin_info *bin)
-{
- int ret = 0;
-
- if (!bin) {
- ret = -1;
- goto end;
- }
-
- /* First try to set the DWARF info from the ELF file */
- ret = bin_info_set_dwarf_info_from_path(bin, bin->elf_path);
- if (!ret) {
- goto end;
- }
-
- /*
- * If that fails, try to find separate debug info via build ID
- * and debug link.
- */
- ret = bin_info_set_dwarf_info_build_id(bin);
- if (!ret) {
- goto end;
- }
-
- ret = bin_info_set_dwarf_info_debug_link(bin);
- if (!ret) {
- goto end;
- }
-
-end:
- return ret;
-}
-
-/**
- * Initialize the ELF file for a given executable.
- *
- * @param bin bin_info instance
- * @returns 0 on success, negative value on error.
- */
-static
-int bin_info_set_elf_file(struct bin_info *bin)
-{
- int elf_fd = -1;
- Elf *elf_file = NULL;
-
- if (!bin) {
- goto error;
- }
-
- elf_fd = open(bin->elf_path, O_RDONLY);
- if (elf_fd < 0) {
- elf_fd = -errno;
- printf_verbose("Failed to open %s\n", bin->elf_path);
- goto error;
- }
-
- elf_file = elf_begin(elf_fd, ELF_C_READ, NULL);
- if (!elf_file) {
- printf_debug("elf_begin failed: %s\n", elf_errmsg(-1));
- goto error;
- }
-
- if (elf_kind(elf_file) != ELF_K_ELF) {
- printf_verbose("Error: %s is not an ELF object\n",
- bin->elf_path);
- goto error;
- }
-
- bin->elf_fd = elf_fd;
- bin->elf_file = elf_file;
- return 0;
-
-error:
- if (elf_fd >= 0) {
- close(elf_fd);
- elf_fd = -1;
- }
- elf_end(elf_file);
- return elf_fd;
-}
-
-BT_HIDDEN
-void source_location_destroy(struct source_location *src_loc)
-{
- if (!src_loc) {
- return;
- }
-
- free(src_loc->filename);
- g_free(src_loc);
-}
-
-/**
- * Append a string representation of an address offset to an existing
- * string.
- *
- * On success, the out parameter `result` will contain the base string
- * followed by the offset string of the form "+0x1234". On failure,
- * `result` remains unchanged.
- *
- * @param base_str The string to which to append an offset string
- * @param low_addr The lower virtual memory address, the base from
- * which the offset is computed
- * @param high_addr The higher virtual memory address
- * @param result Out parameter, the base string followed by the
- * offset string
- * @returns 0 on success, -1 on failure
- */
-static
-int bin_info_append_offset_str(const char *base_str, uint64_t low_addr,
- uint64_t high_addr, char **result)
-{
- int ret;
- uint64_t offset;
- char *_result = NULL;
- char offset_str[ADDR_STR_LEN];
-
- if (!base_str || !result) {
- goto error;
- }
-
- offset = high_addr - low_addr;
-
- _result = malloc(strlen(base_str) + ADDR_STR_LEN);
- if (!_result) {
- goto error;
- }
-
- ret = snprintf(offset_str, ADDR_STR_LEN, "+%#0" PRIx64, offset);
- if (ret < 0) {
- goto error;
- }
- strcpy(_result, base_str);
- strcat(_result, offset_str);
- *result = _result;
-
- return 0;
-
-error:
- free(_result);
- return -1;
-}
-
-/**
- * Try to find the symbol closest to an address within a given ELF
- * section.
- *
- * Only function symbols are taken into account. The symbol's address
- * must precede `addr`. A symbol with a closer address might exist
- * after `addr` but is irrelevant because it cannot encompass `addr`.
- *
- * On success, if found, the out parameters `sym` and `shdr` are
- * set. On failure or if none are found, they remain unchanged.
- *
- * @param scn ELF section in which to look for the address
- * @param addr Virtual memory address for which to find the
- * nearest function symbol
- * @param sym Out parameter, the nearest function symbol
- * @param shdr Out parameter, the section header for scn
- * @returns 0 on success, -1 on failure
- */
-static
-int bin_info_get_nearest_symbol_from_section(Elf_Scn *scn, uint64_t addr,
- GElf_Sym **sym, GElf_Shdr **shdr)
-{
- int i;
- size_t symbol_count;
- Elf_Data *data = NULL;
- GElf_Shdr *_shdr = NULL;
- GElf_Sym *nearest_sym = NULL;
-
- if (!scn || !sym || !shdr) {
- goto error;
- }
-
- _shdr = g_new0(GElf_Shdr, 1);
- if (!_shdr) {
- goto error;
- }
-
- _shdr = gelf_getshdr(scn, _shdr);
- if (!_shdr) {
- goto error;
- }
-
- if (_shdr->sh_type != SHT_SYMTAB) {
- /*
- * We are only interested in symbol table (symtab)
- * sections, skip this one.
- */
- goto end;
- }
-
- data = elf_getdata(scn, NULL);
- if (!data) {
- goto error;
- }
-
- symbol_count = _shdr->sh_size / _shdr->sh_entsize;
-
- for (i = 0; i < symbol_count; ++i) {
- GElf_Sym *cur_sym = NULL;
-
- cur_sym = g_new0(GElf_Sym, 1);
- if (!cur_sym) {
- goto error;
- }
- cur_sym = gelf_getsym(data, i, cur_sym);
- if (!cur_sym) {
- goto error;
- }
- if (GELF_ST_TYPE(cur_sym->st_info) != STT_FUNC) {
- /* We're only interested in the functions. */
- g_free(cur_sym);
- continue;
- }
-
- if (cur_sym->st_value <= addr &&
- (!nearest_sym ||
- cur_sym->st_value > nearest_sym->st_value)) {
- g_free(nearest_sym);
- nearest_sym = cur_sym;
- } else {
- g_free(cur_sym);
- }
- }
-
-end:
- if (nearest_sym) {
- *sym = nearest_sym;
- *shdr = _shdr;
- } else {
- g_free(_shdr);
- }
-
- return 0;
-
-error:
- g_free(nearest_sym);
- g_free(_shdr);
- return -1;
-}
-
-/**
- * Get the name of the function containing a given address within an
- * executable using ELF symbols.
- *
- * The function name is in fact the name of the nearest ELF symbol,
- * followed by the offset in bytes between the address and the symbol
- * (in hex), separated by a '+' character.
- *
- * If found, the out parameter `func_name` is set on success. On failure,
- * it remains unchanged.
- *
- * @param bin bin_info instance for the executable containing
- * the address
- * @param addr Virtual memory address for which to find the
- * function name
- * @param func_name Out parameter, the function name
- * @returns 0 on success, -1 on failure
- */
-static
-int bin_info_lookup_elf_function_name(struct bin_info *bin, uint64_t addr,
- char **func_name)
-{
- /*
- * TODO (possible optimisation): if an ELF has no symtab
- * section, it has been stripped. Therefore, it would be wise
- * to store a flag indicating the stripped status after the
- * first iteration to prevent subsequent ones.
- */
- int ret = 0;
- Elf_Scn *scn = NULL;
- GElf_Sym *sym = NULL;
- GElf_Shdr *shdr = NULL;
- char *sym_name = NULL;
-
- /* Set ELF file if it hasn't been accessed yet. */
- if (!bin->elf_file) {
- ret = bin_info_set_elf_file(bin);
- if (ret) {
- /* Failed to set ELF file. */
- goto error;
- }
- }
-
- scn = elf_nextscn(bin->elf_file, scn);
- if (!scn) {
- goto error;
- }
-
- while (scn && !sym) {
- ret = bin_info_get_nearest_symbol_from_section(
- scn, addr, &sym, &shdr);
- if (ret) {
- goto error;
- }
-
- scn = elf_nextscn(bin->elf_file, scn);
- }
-
- if (sym) {
- sym_name = elf_strptr(bin->elf_file, shdr->sh_link,
- sym->st_name);
- if (!sym_name) {
- goto error;
- }
-
- ret = bin_info_append_offset_str(sym_name, sym->st_value, addr,
- func_name);
- if (ret) {
- goto error;
- }
- }
-
- g_free(shdr);
- g_free(sym);
- return 0;
-
-error:
- g_free(shdr);
- g_free(sym);
- return ret;
-}
-
-/**
- * Get the name of the function containing a given address within a
- * given compile unit (CU).
- *
- * If found, the out parameter `func_name` is set on success. On
- * failure, it remains unchanged.
- *
- * @param cu bt_dwarf_cu instance which may contain the address
- * @param addr Virtual memory address for which to find the
- * function name
- * @param func_name Out parameter, the function name
- * @returns 0 on success, -1 on failure
- */
-static
-int bin_info_lookup_cu_function_name(struct bt_dwarf_cu *cu, uint64_t addr,
- char **func_name)
-{
- int ret = 0;
- bool found = false;
- struct bt_dwarf_die *die = NULL;
-
- if (!cu || !func_name) {
- goto error;
- }
-
- die = bt_dwarf_die_create(cu);
- if (!die) {
- goto error;
- }
-
- while (bt_dwarf_die_next(die) == 0) {
- int tag;
-
- ret = bt_dwarf_die_get_tag(die, &tag);
- if (ret) {
- goto error;
- }
-
- if (tag == DW_TAG_subprogram) {
- ret = bt_dwarf_die_contains_addr(die, addr, &found);
- if (ret) {
- goto error;
- }
-
- if (found) {
- break;
- }
- }
- }
-
- if (found) {
- uint64_t low_addr = 0;
- char *die_name = NULL;
-
- ret = bt_dwarf_die_get_name(die, &die_name);
- if (ret) {
- goto error;
- }
-
- ret = dwarf_lowpc(die->dwarf_die, &low_addr);
- if (ret) {
- free(die_name);
- goto error;
- }
-
- ret = bin_info_append_offset_str(die_name, low_addr, addr,
- func_name);
- free(die_name);
- if (ret) {
- goto error;
- }
- }
-
- bt_dwarf_die_destroy(die);
- return 0;
-
-error:
- bt_dwarf_die_destroy(die);
- return -1;
-}
-
-/**
- * Get the name of the function containing a given address within an
- * executable using DWARF debug info.
- *
- * If found, the out parameter `func_name` is set on success. On
- * failure, it remains unchanged.
- *
- * @param bin bin_info instance for the executable containing
- * the address
- * @param addr Virtual memory address for which to find the
- * function name
- * @param func_name Out parameter, the function name
- * @returns 0 on success, -1 on failure
- */
-static
-int bin_info_lookup_dwarf_function_name(struct bin_info *bin, uint64_t addr,
- char **func_name)
-{
- int ret = 0;
- char *_func_name = NULL;
- struct bt_dwarf_cu *cu = NULL;
-
- if (!bin || !func_name) {
- goto error;
- }
-
- cu = bt_dwarf_cu_create(bin->dwarf_info);
- if (!cu) {
- goto error;
- }
-
- while (bt_dwarf_cu_next(cu) == 0) {
- ret = bin_info_lookup_cu_function_name(cu, addr, &_func_name);
- if (ret) {
- goto error;
- }
-
- if (_func_name) {
- break;
- }
- }
-
- if (_func_name) {
- *func_name = _func_name;
- } else {
- goto error;
- }
-
- bt_dwarf_cu_destroy(cu);
- return 0;
-
-error:
- bt_dwarf_cu_destroy(cu);
- return -1;
-}
-
-BT_HIDDEN
-int bin_info_lookup_function_name(struct bin_info *bin, uint64_t addr,
- char **func_name)
-{
- int ret = 0;
- char *_func_name = NULL;
-
- if (!bin || !func_name) {
- goto error;
- }
-
- /* Set DWARF info if it hasn't been accessed yet. */
- if (!bin->dwarf_info && !bin->is_elf_only) {
- ret = bin_info_set_dwarf_info(bin);
- if (ret) {
- printf_verbose("Failed to set bin dwarf info, falling back to ELF lookup.\n");
- /* Failed to set DWARF info, fallback to ELF. */
- bin->is_elf_only = true;
- }
- }
-
- if (!bin_info_has_address(bin, addr)) {
- goto error;
- }
-
- /*
- * Addresses in ELF and DWARF are relative to base address for
- * PIC, so make the address argument relative too if needed.
- */
- if (bin->is_pic) {
- addr -= bin->low_addr;
- }
-
- if (bin->is_elf_only) {
- ret = bin_info_lookup_elf_function_name(bin, addr, &_func_name);
- printf_verbose("Failed to lookup function name (elf), error %i\n", ret);
- } else {
- ret = bin_info_lookup_dwarf_function_name(bin, addr, &_func_name);
- printf_verbose("Failed to lookup function name (dwarf), error %i\n", ret);
- }
-
- *func_name = _func_name;
- return 0;
-
-error:
- return -1;
-}
-
-BT_HIDDEN
-int bin_info_get_bin_loc(struct bin_info *bin, uint64_t addr, char **bin_loc)
-{
- int ret = 0;
- char *_bin_loc = NULL;
-
- if (!bin || !bin_loc) {
- goto error;
- }
-
- if (bin->is_pic) {
- addr -= bin->low_addr;
- ret = asprintf(&_bin_loc, "+%#0" PRIx64, addr);
- } else {
- ret = asprintf(&_bin_loc, "@%#0" PRIx64, addr);
- }
-
- if (ret == -1 || !_bin_loc) {
- goto error;
- }
-
- *bin_loc = _bin_loc;
- return 0;
-
-error:
- return -1;
-}
-
-/**
- * Predicate used to determine whether the children of a given DIE
- * contain a specific address.
- *
- * More specifically, the parameter `die` is expected to be a
- * subprogram (function) DIE, and this predicate tells whether any
- * subroutines are inlined within this function and would contain
- * `addr`.
- *
- * On success, the out parameter `contains` is set with the boolean
- * value indicating whether the DIE's range covers `addr`. On failure,
- * it remains unchanged.
- *
- * Do note that this function advances the position of `die`. If the
- * address is found within one of its children, `die` will be pointing
- * to that child upon returning from the function, allowing to extract
- * the information deemed necessary.
- *
- * @param die The parent DIE in whose children the address will be
- * looked for
- * @param addr The address for which to look for in the DIEs
- * @param contains Out parameter, true if addr is contained,
- * false if not
- * @returns Returns 0 on success, -1 on failure
- */
-static
-int bin_info_child_die_has_address(struct bt_dwarf_die *die, uint64_t addr, bool *contains)
-{
- int ret = 0;
- bool _contains = false;
-
- if (!die) {
- goto error;
- }
-
- ret = bt_dwarf_die_child(die);
- if (ret) {
- goto error;
- }
-
- do {
- int tag;
-
- ret = bt_dwarf_die_get_tag(die, &tag);
- if (ret) {
- goto error;
- }
-
- if (tag == DW_TAG_inlined_subroutine) {
- ret = bt_dwarf_die_contains_addr(die, addr, &_contains);
- if (ret) {
- goto error;
- }
-
- if (_contains) {
- goto end;
- }
- }
- } while (bt_dwarf_die_next(die) == 0);
-
-end:
- *contains = _contains;
- return 0;
-
-error:
- return -1;
-}
-
-/**
- * Lookup the source location for a given address within a CU, making
- * the assumption that it is contained within an inline routine in a
- * function.
- *
- * @param cu bt_dwarf_cu instance in which to look for the address
- * @param addr The address for which to look for
- * @param src_loc Out parameter, the source location (filename and
- * line number) for the address
- * @returns 0 on success, -1 on failure
- */
-static
-int bin_info_lookup_cu_src_loc_inl(struct bt_dwarf_cu *cu, uint64_t addr,
- struct source_location **src_loc)
-{
- int ret = 0;
- bool found = false;
- struct bt_dwarf_die *die = NULL;
- struct source_location *_src_loc = NULL;
-
- if (!cu || !src_loc) {
- goto error;
- }
-
- die = bt_dwarf_die_create(cu);
- if (!die) {
- goto error;
- }
-
- while (bt_dwarf_die_next(die) == 0) {
- int tag;
-
- ret = bt_dwarf_die_get_tag(die, &tag);
- if (ret) {
- goto error;
- }
-
- if (tag == DW_TAG_subprogram) {
- bool contains = false;
-
- ret = bt_dwarf_die_contains_addr(die, addr, &contains);
- if (ret) {
- goto error;
- }
-
- if (contains) {
- /*
- * Try to find an inlined subroutine
- * child of this DIE containing addr.
- */
- ret = bin_info_child_die_has_address(die, addr,
- &found);
- if(ret) {
- goto error;
- }
-
- goto end;
- }
- }
- }
-
-end:
- if (found) {
- char *filename = NULL;
- uint64_t line_no;
-
- _src_loc = g_new0(struct source_location, 1);
- if (!_src_loc) {
- goto error;
- }
-
- ret = bt_dwarf_die_get_call_file(die, &filename);
- if (ret) {
- goto error;
- }
- ret = bt_dwarf_die_get_call_line(die, &line_no);
- if (ret) {
- free(filename);
- goto error;
- }
-
- _src_loc->filename = filename;
- _src_loc->line_no = line_no;
- *src_loc = _src_loc;
- }
-
- bt_dwarf_die_destroy(die);
- return 0;
-
-error:
- source_location_destroy(_src_loc);
- bt_dwarf_die_destroy(die);
- return -1;
-}
-
-/**
- * Lookup the source location for a given address within a CU,
- * assuming that it is contained within an inlined function.
- *
- * A source location can be found regardless of inlining status for
- * this method, but in the case of an inlined function, the returned
- * source location will point not to the callsite but rather to the
- * definition site of the inline function.
- *
- * @param cu bt_dwarf_cu instance in which to look for the address
- * @param addr The address for which to look for
- * @param src_loc Out parameter, the source location (filename and
- * line number) for the address
- * @returns 0 on success, -1 on failure
- */
-static
-int bin_info_lookup_cu_src_loc_no_inl(struct bt_dwarf_cu *cu, uint64_t addr,
- struct source_location **src_loc)
-{
- struct source_location *_src_loc = NULL;
- struct bt_dwarf_die *die = NULL;
- const char *filename = NULL;
- Dwarf_Line *line = NULL;
- Dwarf_Addr line_addr;
- int ret, line_no;
-
- if (!cu || !src_loc) {
- goto error;
- }
-
- die = bt_dwarf_die_create(cu);
- if (!die) {
- goto error;
- }
-
- line = dwarf_getsrc_die(die->dwarf_die, addr);
- if (!line) {
- goto error;
- }
-
- ret = dwarf_lineaddr(line, &line_addr);
- if (ret) {
- goto error;
- }
-
- filename = dwarf_linesrc(line, NULL, NULL);
- if (!filename) {
- goto error;
- }
-
- if (addr == line_addr) {
- _src_loc = g_new0(struct source_location, 1);
- if (!_src_loc) {
- goto error;
- }
-
- ret = dwarf_lineno(line, &line_no);
- if (ret) {
- goto error;
- }
-
- _src_loc->line_no = line_no;
- _src_loc->filename = strdup(filename);
- }
-
- bt_dwarf_die_destroy(die);
-
- if (_src_loc) {
- *src_loc = _src_loc;
- }
-
- return 0;
-
-error:
- source_location_destroy(_src_loc);
- bt_dwarf_die_destroy(die);
- return -1;
-}
-
-/**
- * Get the source location (file name and line number) for a given
- * address within a compile unit (CU).
- *
- * On success, the out parameter `src_loc` is set if found. On
- * failure, it remains unchanged.
- *
- * @param cu bt_dwarf_cu instance for the compile unit which
- * may contain the address
- * @param addr Virtual memory address for which to find the
- * source location
- * @param src_loc Out parameter, the source location
- * @returns 0 on success, -1 on failure
- */
-static
-int bin_info_lookup_cu_src_loc(struct bt_dwarf_cu *cu, uint64_t addr,
- struct source_location **src_loc)
-{
- int ret = 0;
- struct source_location *_src_loc = NULL;
-
- if (!cu || !src_loc) {
- goto error;
- }
-
- ret = bin_info_lookup_cu_src_loc_inl(cu, addr, &_src_loc);
- if (ret) {
- goto error;
- }
-
- if (_src_loc) {
- goto end;
- }
-
- ret = bin_info_lookup_cu_src_loc_no_inl(cu, addr, &_src_loc);
- if (ret) {
- goto error;
- }
-
- if (_src_loc) {
- goto end;
- }
-
-end:
- if (_src_loc) {
- *src_loc = _src_loc;
- }
-
- return 0;
-
-error:
- source_location_destroy(_src_loc);
- return -1;
-}
-
-BT_HIDDEN
-int bin_info_lookup_source_location(struct bin_info *bin, uint64_t addr,
- struct source_location **src_loc)
-{
- struct bt_dwarf_cu *cu = NULL;
- struct source_location *_src_loc = NULL;
-
- if (!bin || !src_loc) {
- goto error;
- }
-
- /* Set DWARF info if it hasn't been accessed yet. */
- if (!bin->dwarf_info && !bin->is_elf_only) {
- if (bin_info_set_dwarf_info(bin)) {
- /* Failed to set DWARF info. */
- bin->is_elf_only = true;
- }
- }
-
- if (bin->is_elf_only) {
- /* We cannot lookup source location without DWARF info. */
- goto error;
- }
-
- if (!bin_info_has_address(bin, addr)) {
- goto error;
- }
-
- /*
- * Addresses in ELF and DWARF are relative to base address for
- * PIC, so make the address argument relative too if needed.
- */
- if (bin->is_pic) {
- addr -= bin->low_addr;
- }
-
- cu = bt_dwarf_cu_create(bin->dwarf_info);
- if (!cu) {
- goto error;
- }
-
- while (bt_dwarf_cu_next(cu) == 0) {
- int ret;
-
- ret = bin_info_lookup_cu_src_loc(cu, addr, &_src_loc);
- if (ret) {
- goto error;
- }
-
- if (_src_loc) {
- break;
- }
- }
-
- bt_dwarf_cu_destroy(cu);
- if (_src_loc) {
- *src_loc = _src_loc;
- }
-
- return 0;
-
-error:
- source_location_destroy(_src_loc);
- bt_dwarf_cu_destroy(cu);
- return -1;
-}
projects / babeltrace.git / blobdiff