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dwarf_info.c
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dwarf_info.c
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/*
* dwarf_info.c
*
* Copyright (C) 2011 NEC Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <elfutils/libdw.h>
#include <elfutils/libdwfl.h>
#include <dwarf.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include "common.h"
#include "print_info.h"
#include "dwarf_info.h"
/*
* Debugging information
*/
#define DEFAULT_DEBUGINFO_PATH "/usr/lib/debug"
struct dwarf_info {
unsigned int cmd; /* IN */
int fd_debuginfo; /* IN */
char *name_debuginfo; /* IN */
char *module_name; /* IN */
char *struct_name; /* IN */
char *symbol_name; /* IN */
char *member_name; /* IN */
char *enum_name; /* IN */
Elf *elfd; /* OUT */
Dwarf *dwarfd; /* OUT */
Dwfl *dwfl; /* OUT */
char *type_name; /* OUT */
long struct_size; /* OUT */
long member_offset; /* OUT */
long array_length; /* OUT */
long enum_number; /* OUT */
unsigned char type_flag; /* OUT */
Dwarf_Off die_offset; /* OUT */
};
static struct dwarf_info dwarf_info = {
.fd_debuginfo = -1,
};
/*
* Internal functions.
*/
static int
is_search_structure(int cmd)
{
if ((cmd == DWARF_INFO_GET_STRUCT_SIZE)
|| (cmd == DWARF_INFO_GET_MEMBER_OFFSET)
|| (cmd == DWARF_INFO_GET_MEMBER_TYPE)
|| (cmd == DWARF_INFO_GET_MEMBER_OFFSET_1ST_UNION)
|| (cmd == DWARF_INFO_GET_MEMBER_ARRAY_LENGTH))
return TRUE;
else
return FALSE;
}
static int
is_search_number(int cmd)
{
if (cmd == DWARF_INFO_GET_ENUM_NUMBER)
return TRUE;
else
return FALSE;
}
static int
is_search_symbol(int cmd)
{
if ((cmd == DWARF_INFO_GET_SYMBOL_ARRAY_LENGTH)
|| (cmd == DWARF_INFO_GET_SYMBOL_TYPE)
|| (cmd == DWARF_INFO_CHECK_SYMBOL_ARRAY_TYPE))
return TRUE;
else
return FALSE;
}
static int
is_search_typedef(int cmd)
{
if ((cmd == DWARF_INFO_GET_TYPEDEF_SIZE)
|| (cmd == DWARF_INFO_GET_TYPEDEF_SRCNAME))
return TRUE;
else
return FALSE;
}
static int
is_search_domain(int cmd)
{
if ((cmd == DWARF_INFO_GET_DOMAIN_STRUCT)
|| (cmd == DWARF_INFO_GET_DOMAIN_TYPEDEF)
|| (cmd == DWARF_INFO_GET_DOMAIN_ARRAY)
|| (cmd == DWARF_INFO_GET_DOMAIN_UNION)
|| (cmd == DWARF_INFO_GET_DOMAIN_ENUM)
|| (cmd == DWARF_INFO_GET_DOMAIN_REF)
|| (cmd == DWARF_INFO_GET_DOMAIN_STRING)
|| (cmd == DWARF_INFO_GET_DOMAIN_BASE))
return TRUE;
else
return FALSE;
}
static int
is_search_die(int cmd)
{
if (cmd == DWARF_INFO_GET_DIE)
return TRUE;
else
return FALSE;
}
static int
process_module (Dwfl_Module *dwflmod,
void **userdata __attribute__ ((unused)),
const char *name __attribute__ ((unused)),
Dwarf_Addr base __attribute__ ((unused)),
void *arg)
{
const char *fname, *mod_name, *debugfile;
Dwarf_Addr dwbias;
/* get a debug context descriptor.*/
dwarf_info.dwarfd = dwfl_module_getdwarf (dwflmod, &dwbias);
if (dwarf_info.dwarfd == NULL) {
ERRMSG("dwfl_module_getdwarf error.\n");
return DWARF_CB_ABORT;
}
dwarf_info.elfd = dwarf_getelf(dwarf_info.dwarfd);
mod_name = dwfl_module_info(dwflmod, NULL, NULL, NULL, NULL, NULL,
&fname, &debugfile);
if (!strcmp(dwarf_info.module_name, mod_name) &&
!dwarf_info.name_debuginfo && debugfile) {
/*
* Store the debuginfo filename. Next time we will
* open debuginfo file direclty instead of searching
* for it again.
*/
dwarf_info.name_debuginfo = strdup(debugfile);
}
return DWARF_CB_OK;
}
static int
dwfl_report_module_p(const char *modname, const char *filename)
{
if (filename && !strcmp(modname, dwarf_info.module_name))
return 1;
return 0;
}
static void
clean_dwfl_info(void)
{
if (dwarf_info.dwfl)
dwfl_end(dwarf_info.dwfl);
dwarf_info.dwfl = NULL;
dwarf_info.dwarfd = NULL;
dwarf_info.elfd = NULL;
}
/*
* Search module debuginfo.
* This function searches for module debuginfo in default debuginfo path for
* a given module in dwarf_info.module_name.
*
* On success, dwarf_info.name_debuginfo is set to absolute path of
* module debuginfo.
*/
static int
search_module_debuginfo(char *os_release)
{
Dwfl *dwfl = NULL;
static char *debuginfo_path = DEFAULT_DEBUGINFO_PATH;
static const Dwfl_Callbacks callbacks = {
.section_address = dwfl_offline_section_address,
.find_debuginfo = dwfl_standard_find_debuginfo,
.debuginfo_path = &debuginfo_path,
};
/*
* Check if We already have debuginfo file name with us. If yes,
* then we don't need to proceed with search method.
*/
if (dwarf_info.name_debuginfo)
return TRUE;
if ((dwfl = dwfl_begin(&callbacks)) == NULL) {
ERRMSG("Can't create a handle for a new dwfl session.\n");
return FALSE;
}
/* Search for module debuginfo file. */
if (dwfl_linux_kernel_report_offline(dwfl,
os_release,
&dwfl_report_module_p)) {
ERRMSG("Can't get Module debuginfo for module '%s'\n",
dwarf_info.module_name);
dwfl_end(dwfl);
return FALSE;
}
dwfl_report_end(dwfl, NULL, NULL);
dwfl_getmodules(dwfl, &process_module, NULL, 0);
dwfl_end(dwfl);
clean_dwfl_info();
/* Return success if module debuginfo is found. */
if (dwarf_info.name_debuginfo)
return TRUE;
return FALSE;
}
static int
dwarf_no_debuginfo_found(Dwfl_Module *mod, void **userdata,
const char *modname, Dwarf_Addr base,
const char *file_name,
const char *debuglink_file, GElf_Word debuglink_crc,
char **debuginfo_file_name)
{
return -1;
}
/*
* Initialize the dwarf info.
* Linux kernel module debuginfo are of ET_REL (relocatable) type.
* This function uses dwfl API's to apply relocation before reading the
* dwarf information from module debuginfo.
* On success, this function sets the dwarf_info.elfd and dwarf_info.dwarfd
* after applying relocation to module debuginfo.
*/
static int
init_dwarf_info(void)
{
Dwfl *dwfl = NULL;
int dwfl_fd = -1;
static const Dwfl_Callbacks callbacks = {
.section_address = dwfl_offline_section_address,
/*
* By the time init_dwarf_info() function is called, we already
* know absolute path of debuginfo either resolved through
* search_module_debuginfo() call OR user specified vmlinux
* debuginfo through '-x' option. In which case .find_debuginfo
* callback is never invoked.
* But we can not deny a situation where user may pass invalid
* file name through '-x' option, where .find_debuginfo gets
* invoked to find a valid vmlinux debuginfo and hence we run
* into seg fault issue. Hence, set .find_debuginfo to a
* funtion pointer that returns -1 to avoid seg fault and let
* the makedumpfile throw error messages against the invalid
* vmlinux file input.
*/
.find_debuginfo = dwarf_no_debuginfo_found
};
dwarf_info.elfd = NULL;
dwarf_info.dwarfd = NULL;
/*
* We already know the absolute path of debuginfo file. Fail if we
* still don't have one. Ideally we should never be in this situation.
*/
if (!dwarf_info.name_debuginfo) {
ERRMSG("Can't find absolute path to debuginfo file.\n");
return FALSE;
}
if ((dwfl = dwfl_begin(&callbacks)) == NULL) {
ERRMSG("Can't create a handle for a new dwfl session.\n");
return FALSE;
}
/* Open the debuginfo file if it is not already open. */
if (dwarf_info.fd_debuginfo < 0)
dwarf_info.fd_debuginfo =
open(dwarf_info.name_debuginfo, O_RDONLY);
dwfl_fd = dup(dwarf_info.fd_debuginfo);
if (dwfl_fd < 0) {
ERRMSG("Failed to get a duplicate handle for"
" debuginfo.\n");
goto err_out;
}
/* Apply relocations. */
if (dwfl_report_offline(dwfl, dwarf_info.module_name,
dwarf_info.name_debuginfo, dwfl_fd) == NULL) {
ERRMSG("Failed reading %s: %s\n",
dwarf_info.name_debuginfo, dwfl_errmsg (-1));
/* dwfl_fd is consumed on success, not on failure */
close(dwfl_fd);
goto err_out;
}
dwfl_report_end(dwfl, NULL, NULL);
dwfl_getmodules(dwfl, &process_module, NULL, 0);
if (dwarf_info.elfd == NULL) {
ERRMSG("Can't get first elf header of %s.\n",
dwarf_info.name_debuginfo);
goto err_out;
}
if (dwarf_info.dwarfd == NULL) {
ERRMSG("Can't get debug context descriptor for %s.\n",
dwarf_info.name_debuginfo);
goto err_out;
}
dwarf_info.dwfl = dwfl;
return TRUE;
err_out:
if (dwfl)
dwfl_end(dwfl);
return FALSE;
}
static int
get_data_member_location(Dwarf_Die *die, long *offset)
{
size_t expcnt;
Dwarf_Attribute attr;
Dwarf_Op *expr;
if (dwarf_attr(die, DW_AT_data_member_location, &attr) == NULL)
return FALSE;
if (dwarf_getlocation(&attr, &expr, &expcnt) < 0)
return FALSE;
(*offset) = expr[0].number;
return TRUE;
}
static int
get_die_type(Dwarf_Die *die, Dwarf_Die *die_type)
{
Dwarf_Attribute attr;
if (dwarf_attr(die, DW_AT_type, &attr) == NULL)
return FALSE;
if (dwarf_formref_die(&attr, die_type) < 0) {
ERRMSG("Can't get CU die.\n");
return FALSE;
}
return TRUE;
}
static int
get_data_array_length(Dwarf_Die *die)
{
int tag;
Dwarf_Attribute attr;
Dwarf_Die die_type;
Dwarf_Word upper_bound;
if (!get_die_type(die, &die_type)) {
ERRMSG("Can't get CU die of DW_AT_type.\n");
return FALSE;
}
tag = dwarf_tag(&die_type);
if (tag == DW_TAG_const_type) {
/* This array is of const type. Get the die type again */
if (!get_die_type(&die_type, &die_type)) {
ERRMSG("Can't get CU die of DW_AT_type.\n");
return FALSE;
}
tag = dwarf_tag(&die_type);
}
if (tag != DW_TAG_array_type) {
/*
* This kernel doesn't have the member of array.
*/
return TRUE;
}
/*
* Get the demanded array length.
*/
dwarf_child(&die_type, &die_type);
do {
tag = dwarf_tag(&die_type);
if (tag == DW_TAG_subrange_type)
break;
} while (dwarf_siblingof(&die_type, &die_type));
if (tag != DW_TAG_subrange_type)
return FALSE;
if (dwarf_attr(&die_type, DW_AT_upper_bound, &attr) == NULL)
return FALSE;
if (dwarf_formudata(&attr, &upper_bound) < 0)
return FALSE;
if (upper_bound < 0)
return FALSE;
dwarf_info.array_length = upper_bound + 1;
return TRUE;
}
static int
check_array_type(Dwarf_Die *die)
{
int tag;
Dwarf_Die die_type;
if (!get_die_type(die, &die_type)) {
ERRMSG("Can't get CU die of DW_AT_type.\n");
return FALSE;
}
tag = dwarf_tag(&die_type);
if (tag == DW_TAG_array_type)
dwarf_info.array_length = FOUND_ARRAY_TYPE;
return TRUE;
}
static int
get_dwarf_base_type(Dwarf_Die *die)
{
int tag;
const char *name;
while (get_die_type(die, die)) {
tag = dwarf_tag(die);
switch (tag) {
case DW_TAG_array_type:
dwarf_info.type_flag |= TYPE_ARRAY;
break;
case DW_TAG_pointer_type:
dwarf_info.type_flag |= TYPE_PTR;
break;
case DW_TAG_structure_type:
dwarf_info.type_flag |= TYPE_STRUCT;
break;
case DW_TAG_base_type:
dwarf_info.type_flag |= TYPE_BASE;
break;
}
}
name = dwarf_diename(die);
if (name)
dwarf_info.type_name = strdup(name);
else if (dwarf_info.type_flag == TYPE_PTR)
dwarf_info.type_name = strdup("void");
dwarf_info.struct_size = dwarf_bytesize(die);
return TRUE;
}
/*
* Get the die, given the offset
*/
static int
get_die_from_offset(Dwarf_Off offset, Dwarf_Die *die)
{
if (!init_dwarf_info())
return FALSE;
if ((!offset) || (!die))
return FALSE;
if (!dwarf_offdie(dwarf_info.dwarfd, offset, die)) {
return FALSE;
}
return TRUE;
}
/*
* Function for searching struct page.union.struct.mapping.
*/
static int
is_container(Dwarf_Die *die)
{
if (dwarf_tag(die) == DW_TAG_structure_type)
return TRUE;
if (dwarf_info.cmd != DWARF_INFO_GET_MEMBER_OFFSET_1ST_UNION
&& dwarf_tag(die) == DW_TAG_union_type)
return TRUE;
return FALSE;
}
static void
adjust_member_offset(Dwarf_Die *die)
{
long offset;
if (dwarf_info.member_offset == NOT_FOUND_STRUCTURE)
return;
if (!get_data_member_location(die, &offset))
return;
dwarf_info.member_offset += offset;
}
static int
search_member(Dwarf_Die *die)
{
int tag;
long offset;
const char *name;
Dwarf_Die child, *walker, die_type;
if (dwarf_child(die, &child) != 0)
return FALSE;
walker = &child;
do {
tag = dwarf_tag(walker);
name = dwarf_diename(walker);
if (tag != DW_TAG_member)
continue;
/*
* Descend into structures/unions and search for member
* there.
*/
if ((!name) || (strcmp(name, dwarf_info.member_name) != 0)) {
if (!get_die_type(walker, &die_type))
continue;
if (is_container(&die_type))
if (search_member(&die_type)) {
adjust_member_offset(walker);
return TRUE;
}
}
switch (dwarf_info.cmd) {
case DWARF_INFO_GET_MEMBER_TYPE:
if ((!name) || strcmp(name, dwarf_info.member_name))
continue;
/*
* Get the member offset.
*/
if (!get_dwarf_base_type(walker))
continue;
return TRUE;
case DWARF_INFO_GET_MEMBER_OFFSET:
if ((!name) || strcmp(name, dwarf_info.member_name))
continue;
/*
* Get the member offset.
*/
if (dwarf_tag(die) == DW_TAG_union_type)
offset = 0;
else if (!get_data_member_location(walker, &offset))
continue;
dwarf_info.member_offset = offset;
return TRUE;
case DWARF_INFO_GET_MEMBER_OFFSET_1ST_UNION:
if (!get_die_type(walker, &die_type))
continue;
if (dwarf_tag(&die_type) != DW_TAG_union_type)
continue;
/*
* Get the member offset.
*/
if (!get_data_member_location(walker, &offset))
continue;
dwarf_info.member_offset = offset;
return TRUE;
case DWARF_INFO_GET_MEMBER_ARRAY_LENGTH:
if ((!name) || strcmp(name, dwarf_info.member_name))
continue;
/*
* Get the member length.
*/
if (!get_data_array_length(walker))
continue;
return TRUE;
}
} while (!dwarf_siblingof(walker, walker));
/*
* Return even if not found.
*/
return FALSE;
}
static void
search_structure(Dwarf_Die *die, int *found)
{
int tag;
const char *name;
Dwarf_Die die_type;
/*
* If we get to here then we don't have any more
* children, check to see if this is a relevant tag
*/
do {
tag = dwarf_tag(die);
name = dwarf_diename(die);
if ((!name) || strcmp(name, dwarf_info.struct_name))
continue;
if (tag == DW_TAG_typedef) {
if (!get_die_type(die, &die_type)) {
ERRMSG("Can't get CU die of DW_AT_type.\n");
break;
}
/* Resolve typedefs of typedefs. */
while ((tag = dwarf_tag(&die_type)) == DW_TAG_typedef) {
if (!get_die_type(&die_type, &die_type)) {
ERRMSG("Can't get CU die of DW_AT_type.\n");
return;
}
}
if (tag != DW_TAG_structure_type)
continue;
die = &die_type;
} else if (tag != DW_TAG_structure_type) {
continue;
}
/*
* Skip if DW_AT_byte_size is not included.
*/
dwarf_info.struct_size = dwarf_bytesize(die);
if (dwarf_info.struct_size > 0)
break;
} while (!dwarf_siblingof(die, die));
if (dwarf_info.struct_size <= 0) {
/*
* Not found the demanded structure.
*/
return;
}
/*
* Found the demanded structure.
*/
*found = TRUE;
switch (dwarf_info.cmd) {
case DWARF_INFO_GET_STRUCT_SIZE:
break;
case DWARF_INFO_GET_MEMBER_TYPE:
case DWARF_INFO_GET_MEMBER_OFFSET:
case DWARF_INFO_GET_MEMBER_OFFSET_1ST_UNION:
case DWARF_INFO_GET_MEMBER_ARRAY_LENGTH:
search_member(die);
break;
}
}
static void
search_number(Dwarf_Die *die, int *found)
{
int tag, bytesize;
Dwarf_Word const_value;
Dwarf_Attribute attr;
Dwarf_Die child, *walker;
const char *name;
do {
tag = dwarf_tag(die);
if (tag != DW_TAG_enumeration_type)
continue;
if (dwarf_info.cmd == DWARF_INFO_GET_ENUMERATION_TYPE_SIZE) {
name = dwarf_diename(die);
if (!name || strcmp(name, dwarf_info.struct_name))
continue;
if ((bytesize = dwarf_bytesize(die)) <= 0)
continue;
*found = TRUE;
dwarf_info.struct_size = bytesize;
return;
}
if (dwarf_child(die, &child) != 0)
continue;
walker = &child;
do {
tag = dwarf_tag(walker);
name = dwarf_diename(walker);
if ((tag != DW_TAG_enumerator) || (!name)
|| strcmp(name, dwarf_info.enum_name))
continue;
if (!dwarf_attr(walker, DW_AT_const_value, &attr))
continue;
if (dwarf_formudata(&attr, &const_value) < 0)
continue;
*found = TRUE;
dwarf_info.enum_number = (long)const_value;
} while (!dwarf_siblingof(walker, walker));
} while (!dwarf_siblingof(die, die));
}
static void
search_typedef(Dwarf_Die *die, int *found)
{
int tag = 0;
const char *name;
Dwarf_Die die_type;
/*
* If we get to here then we don't have any more
* children, check to see if this is a relevant tag
*/
do {
tag = dwarf_tag(die);
name = dwarf_diename(die);
if ((tag != DW_TAG_typedef) || (!name)
|| strcmp(name, dwarf_info.struct_name))
continue;
if (dwarf_info.cmd == DWARF_INFO_GET_TYPEDEF_SIZE) {
if (!get_die_type(die, &die_type)) {
ERRMSG("Can't get CU die of DW_AT_type.\n");
break;
}
/* Resolve typedefs of typedefs. */
while ((tag = dwarf_tag(&die_type)) == DW_TAG_typedef) {
if (!get_die_type(&die_type, &die_type)) {
ERRMSG("Can't get CU die of DW_AT_type.\n");
return;
}
}
dwarf_info.struct_size = dwarf_bytesize(&die_type);
if (dwarf_info.struct_size <= 0)
continue;
*found = TRUE;
break;
}
} while (!dwarf_siblingof(die, die));
}
static void
search_symbol(Dwarf_Die *die, int *found)
{
int tag;
const char *name;
/*
* If we get to here then we don't have any more
* children, check to see if this is a relevant tag
*/
do {
tag = dwarf_tag(die);
name = dwarf_diename(die);
if ((tag == DW_TAG_variable) && (name)
&& !strcmp(name, dwarf_info.symbol_name))
break;
} while (!dwarf_siblingof(die, die));
if ((tag != DW_TAG_variable) || (!name)
|| strcmp(name, dwarf_info.symbol_name)) {
/*
* Not found the demanded symbol.
*/
return;
}
/*
* Found the demanded symbol.
*/
*found = TRUE;
switch (dwarf_info.cmd) {
case DWARF_INFO_GET_SYMBOL_ARRAY_LENGTH:
get_data_array_length(die);
break;
case DWARF_INFO_CHECK_SYMBOL_ARRAY_TYPE:
check_array_type(die);
break;
case DWARF_INFO_GET_SYMBOL_TYPE:
get_dwarf_base_type(die);
break;
}
}
static void
search_domain(Dwarf_Die *die, int *found)
{
int tag;
const char *name;
short flag = 0;
Dwarf_Die die_type;
do {
tag = dwarf_tag(die);
name = dwarf_diename(die);
/*
* Descend into members and search for the
* needed domain there.
*/
if ((!name) || strcmp(name, dwarf_info.symbol_name)) {
if (!get_die_type(die, &die_type))
continue;
if (is_container(&die_type)) {
Dwarf_Die child;
if (dwarf_child(&die_type, &child) != 0)
continue;
search_domain(&child, found);
if (*found)
return;
}
}
if ((!name) || strcmp(name, dwarf_info.symbol_name))
continue;
switch (dwarf_info.cmd) {
case DWARF_INFO_GET_DOMAIN_STRUCT:
if (tag == DW_TAG_structure_type)
flag = 1;
break;
case DWARF_INFO_GET_DOMAIN_UNION:
if (tag == DW_TAG_union_type)
flag = 1;
break;
case DWARF_INFO_GET_DOMAIN_TYPEDEF:
if (tag == DW_TAG_typedef)
flag = 1;
break;
/* TODO
* Implement functionality for the rest of the domains
*/
}
if (!flag)
continue;
dwarf_info.struct_size = dwarf_bytesize(die);
if (dwarf_info.struct_size > 0) {
if (found)
*found = TRUE;
dwarf_info.die_offset = dwarf_dieoffset(die);
break;
}
} while (!dwarf_siblingof(die, die));
}
static void
search_die(Dwarf_Die *die, int *found)
{
const char *name;
do {
name = dwarf_diename(die);
if ((!name) || strcmp(name, dwarf_info.symbol_name))
continue;
if (found)
*found = TRUE;
dwarf_info.die_offset = dwarf_dieoffset(die);
return;
} while (!dwarf_siblingof(die, die));
}
static void
search_die_tree(Dwarf_Die *die, int *found)
{
Dwarf_Die child;
/*
* start by looking at the children
*/
if (dwarf_child(die, &child) == 0)
search_die_tree(&child, found);
if (*found)
return;
if (is_search_structure(dwarf_info.cmd))
search_structure(die, found);
else if (is_search_number(dwarf_info.cmd))
search_number(die, found);
else if (is_search_symbol(dwarf_info.cmd))
search_symbol(die, found);
else if (is_search_typedef(dwarf_info.cmd))
search_typedef(die, found);
else if (is_search_domain(dwarf_info.cmd))
search_domain(die, found);
else if (is_search_die(dwarf_info.cmd))
search_die(die, found);
}
static int
get_debug_info(void)
{
int found = FALSE;
char *name = NULL;
size_t shstrndx, header_size;
uint8_t address_size, offset_size;
Dwarf *dwarfd = NULL;
Elf *elfd = NULL;
Dwarf_Off off = 0, next_off = 0, abbrev_offset = 0;
Elf_Scn *scn = NULL;
GElf_Shdr scnhdr_mem, *scnhdr = NULL;
Dwarf_Die cu_die;
int ret = FALSE;
if (!init_dwarf_info())
return FALSE;
elfd = dwarf_info.elfd;
dwarfd = dwarf_info.dwarfd;
if (elf_getshdrstrndx(elfd, &shstrndx) < 0) {
ERRMSG("Can't get the section index of the string table.\n");
goto out;
}
/*
* Search for ".debug_info" section.
*/
while ((scn = elf_nextscn(elfd, scn)) != NULL) {
scnhdr = gelf_getshdr(scn, &scnhdr_mem);
name = elf_strptr(elfd, shstrndx, scnhdr->sh_name);
if (!strcmp(name, ".debug_info"))
break;
}
if (strcmp(name, ".debug_info")) {
ERRMSG("Can't get .debug_info section.\n");
goto out;
}
/*
* Search by each CompileUnit.
*/
while (dwarf_nextcu(dwarfd, off, &next_off, &header_size,
&abbrev_offset, &address_size, &offset_size) == 0) {
off += header_size;
if (dwarf_offdie(dwarfd, off, &cu_die) == NULL) {
ERRMSG("Can't get CU die.\n");
goto out;
}
search_die_tree(&cu_die, &found);
if (found)