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/* Sysprof -- Sampling, systemwide CPU profiler
* Copyright 2006, 2007, Soeren Sandmann
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdlib.h>
#include <string.h>
#ifdef __APPLE__
# include <libelf.h>
#else
# include <elf.h>
#endif
#include <sys/mman.h>
#include "demangle.h"
#include "elfparser.h"
#include "rust-demangle.h"
typedef struct Section Section;
struct ElfSym
{
gulong table;
gulong offset;
gulong address;
};
struct Section
{
const gchar * name;
gsize offset;
gsize size;
gboolean allocated;
gulong load_address;
guint type;
};
struct ElfParser
{
gboolean is_64;
const guchar * data;
gsize length;
guint n_sections;
Section ** sections;
guint n_symbols;
ElfSym * symbols;
gsize sym_strings;
GMappedFile * file;
char * filename;
gboolean checked_build_id;
char * build_id;
const Section * text_section;
};
/* FIXME: All of these should in principle do endian swapping,
* but sysprof never has to deal with binaries of a different
* endianness than sysprof itself
*/
#define GET_FIELD(parser, offset, struct_name, idx, field_name) \
(((parser))->is_64? \
((Elf64_ ## struct_name *)(gpointer)(((parser)->data + offset)) + (idx))->field_name : \
((Elf32_ ## struct_name *)(gpointer)(((parser)->data + offset)) + (idx))->field_name)
#define GET_UINT32(parser, offset) \
*((uint32_t *)(gpointer)(parser->data + offset)) \
#define GET_SIZE(parser, struct_name) \
(((parser)->is_64? \
sizeof (Elf64_ ## struct_name) : \
sizeof (Elf32_ ## struct_name)))
#define MAKE_ELF_UINT_ACCESSOR(field_name) \
static uint64_t field_name (ElfParser *parser) \
{ \
return GET_FIELD (parser, 0, Ehdr, 0, field_name); \
}
MAKE_ELF_UINT_ACCESSOR (e_shoff)
MAKE_ELF_UINT_ACCESSOR (e_shnum)
MAKE_ELF_UINT_ACCESSOR (e_shstrndx)
#define MAKE_SECTION_HEADER_ACCESSOR(field_name) \
static uint64_t field_name (ElfParser *parser, int nth_section) \
{ \
gsize offset = e_shoff (parser); \
\
return GET_FIELD (parser, offset, Shdr, nth_section, field_name); \
}
MAKE_SECTION_HEADER_ACCESSOR (sh_name);
MAKE_SECTION_HEADER_ACCESSOR (sh_type);
MAKE_SECTION_HEADER_ACCESSOR (sh_flags);
MAKE_SECTION_HEADER_ACCESSOR (sh_addr);
MAKE_SECTION_HEADER_ACCESSOR (sh_offset);
MAKE_SECTION_HEADER_ACCESSOR (sh_size);
#define MAKE_SYMBOL_ACCESSOR(field_name) \
static uint64_t field_name (ElfParser *parser, gulong offset, gulong nth) \
{ \
return GET_FIELD (parser, offset, Sym, nth, field_name); \
}
MAKE_SYMBOL_ACCESSOR(st_name);
MAKE_SYMBOL_ACCESSOR(st_info);
MAKE_SYMBOL_ACCESSOR(st_value);
MAKE_SYMBOL_ACCESSOR(st_size);
MAKE_SYMBOL_ACCESSOR(st_shndx);
static gboolean
in_container (void)
{
static gboolean _in_container;
static gboolean initialized;
if (!initialized)
{
/* Flatpak has /.flatpak-info
* Podman has /run/.containerenv
*
* Both have access to host files via /var/run/host.
*/
_in_container = g_file_test ("/.flatpak-info", G_FILE_TEST_EXISTS) ||
g_file_test ("/run/.containerenv", G_FILE_TEST_EXISTS);
initialized = TRUE;
}
return _in_container;
}
static void
section_free (Section *section)
{
g_free (section);
}
static const Section *
find_section (ElfParser *parser,
const char *name,
guint type)
{
guint i;
for (i = 0; i < parser->n_sections; ++i)
{
Section *section = parser->sections[i];
if (strcmp (section->name, name) == 0 && section->type == type)
return section;
}
return NULL;
}
static gboolean
parse_elf_signature (const guchar *data,
gsize length,
gboolean *is_64,
gboolean *is_be)
{
/* FIXME: this function should be able to return an error */
if (length < EI_NIDENT)
{
/* FIXME set error */
return FALSE;
}
if (data[EI_CLASS] != ELFCLASS32 &&
data[EI_CLASS] != ELFCLASS64)
{
/* FIXME set error */
return FALSE;
}
if (data[EI_DATA] != ELFDATA2LSB &&
data[EI_DATA] != ELFDATA2MSB)
{
/* FIXME set error */
return FALSE;
}
if (is_64)
*is_64 = (data[EI_CLASS] == ELFCLASS64);
if (is_be)
*is_be = (data[EI_DATA] == ELFDATA2MSB);
return TRUE;
}
ElfParser *
elf_parser_new_from_data (const guchar *data,
gsize length)
{
ElfParser *parser;
gboolean is_64, is_big_endian;
int section_names_idx;
const guchar *section_names;
G_GNUC_UNUSED gsize section_headers;
guint i;
if (!parse_elf_signature (data, length, &is_64, &is_big_endian))
{
/* FIXME: set error */
return NULL;
}
parser = g_new0 (ElfParser, 1);
parser->is_64 = is_64;
parser->data = data;
parser->length = length;
#if 0
g_print (" new parser : %p\n", parser);
#endif
/* Read ELF header */
parser->n_sections = e_shnum (parser);
section_names_idx = e_shstrndx (parser);
section_headers = e_shoff (parser);
/* Read section headers */
parser->sections = g_new0 (Section *, parser->n_sections);
section_names = parser->data + sh_offset (parser, section_names_idx);
for (i = 0; i < parser->n_sections; ++i)
{
Section *section = g_new (Section, 1);
section->name = (char *)(section_names + sh_name (parser, i));
section->size = sh_size (parser, i);
section->offset = sh_offset (parser, i);
section->allocated = !!(sh_flags (parser, i) & SHF_ALLOC);
if (section->allocated)
section->load_address = sh_addr (parser, i);
else
section->load_address = 0;
section->type = sh_type (parser, i);
parser->sections[i] = section;
}
/* Cache the text section */
parser->text_section = find_section (parser, ".text", SHT_PROGBITS);
if (!parser->text_section)
parser->text_section = find_section (parser, ".text", SHT_NOBITS);
parser->filename = NULL;
parser->build_id = NULL;
return parser;
}
static GMappedFile *
open_mapped_file (const char *filename,
GError **error)
{
GMappedFile *file = NULL;
char *alternate = NULL;
if (in_container () && !g_str_has_prefix (filename, g_get_home_dir ()))
{
alternate = g_build_filename ("/var/run/host", filename, NULL);
file = g_mapped_file_new (alternate, FALSE, NULL);
g_free (alternate);
}
/* Flatpaks with filesystem=host don't have Silverblue's /sysroot in /var/run/host,
* yet they have it in /, which means the original path might work.
*/
if (!file)
file = g_mapped_file_new (filename, FALSE, error);
return file;
}
ElfParser *
elf_parser_new_from_mmap (GMappedFile *file,
GError **error)
{
const guchar *data;
gsize length;
ElfParser *parser;
if (file == NULL)
return NULL;
data = (guchar *)g_mapped_file_get_contents (file);
length = g_mapped_file_get_length (file);
parser = elf_parser_new_from_data (data, length);
if (!parser)
{
g_set_error (error,
G_FILE_ERROR,
G_FILE_ERROR_FAILED,
"Failed to load ELF from mmap region");
g_mapped_file_unref (file);
return NULL;
}
parser->filename = NULL;
parser->file = file;
return parser;
}
ElfParser *
elf_parser_new (const char *filename,
GError **error)
{
GMappedFile *file;
const guchar *data;
gsize length;
ElfParser *parser;
if (!(file = open_mapped_file (filename, error)))
return NULL;
#if 0
g_print ("elf parser new : %s\n", filename);
#endif
data = (guchar *)g_mapped_file_get_contents (file);
length = g_mapped_file_get_length (file);
#if 0
g_print ("data %p: for %s\n", data, filename);
#endif
parser = elf_parser_new_from_data (data, length);
#if 0
g_print ("Parser for %s: %p\n", filename, parser);
#endif
if (!parser)
{
g_set_error (error,
G_FILE_ERROR,
G_FILE_ERROR_FAILED,
"Failed to load ELF from file %s",
filename);
g_mapped_file_unref (file);
return NULL;
}
parser->filename = g_strdup (filename);
parser->file = file;
#if 0
g_print ("Elf file: %s (debug: %s)\n",
filename, elf_parser_get_debug_link (parser, NULL));
if (!parser->symbols)
g_print ("at this point %s has no symbols\n", filename);
#endif
return parser;
}
guint32
elf_parser_get_crc32 (ElfParser *parser)
{
static const unsigned long crc32_table[256] = {
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};
const guchar *data;
gsize length;
gulong crc;
gsize i;
data = parser->data;
length = parser->length;
crc = 0xffffffff;
madvise ((char *)data, length, MADV_SEQUENTIAL);
for (i = 0; i < length; ++i)
crc = crc32_table[(crc ^ data[i]) & 0xff] ^ (crc >> 8);
/* We just read the entire file into memory, but we only really
* need the symbol table, so swap the whole thing out.
*
* We could be more exact here, but it's only a few minor
* pagefaults.
*/
if (parser->file)
madvise ((char *)data, length, MADV_DONTNEED);
return ~crc & 0xffffffff;
}
void
elf_parser_free (ElfParser *parser)
{
guint i;
for (i = 0; i < parser->n_sections; ++i)
section_free (parser->sections[i]);
g_free (parser->sections);
if (parser->file)
g_mapped_file_unref (parser->file);
g_free (parser->symbols);
if (parser->filename)
g_free (parser->filename);
if (parser->build_id)
g_free (parser->build_id);
g_free (parser);
}
gchar *
elf_demangle (const char *name)
{
/* Try demangling as rust symbol first as legacy rust symbols can demangle as C++ symbols too
* but will only get partially demangled in that case.
*/
gchar *demangled = sysprof_rust_demangle (name, 0);
if (demangled)
return demangled;
demangled = sysprof_cplus_demangle (name);
if (demangled)
return demangled;
else
return g_strdup (name);
}
/*
* Looking up symbols
*/
static int
compare_sym (const void *a, const void *b)
{
const ElfSym *sym_a = a;
const ElfSym *sym_b = b;
if (sym_a->address < sym_b->address)
return -1;
else if (sym_a->address == sym_b->address)
return 0;
else
return 1;
}
#if 0
static void
dump_symbols (ElfParser *parser, ElfSym *syms, guint n_syms)
{
int i;
for (i = 0; i < n_syms; ++i)
{
ElfSym *s = &(syms[i]);
g_print (" %s: %lx\n", elf_parser_get_sym_name (parser, s), s->address);
}
}
#endif
static void
read_table (ElfParser *parser,
const Section *sym_table,
const Section *str_table)
{
int sym_size = GET_SIZE (parser, Sym);
guint i, n_symbols;
#if 0
g_print ("elf: Reading table for %s\n", parser->filename? parser->filename : "<unknown>");
#endif
parser->n_symbols = sym_table->size / sym_size;
parser->symbols = g_new (ElfSym, parser->n_symbols);
#if 0
g_print ("sym table offset: %d\n", sym_table->offset);
#endif
n_symbols = 0;
#if 0
g_print ("n syms: %d\n", parser->n_symbols);
#endif
for (i = 0; i < parser->n_symbols; ++i)
{
guint info;
gulong addr;
gulong shndx;
info = st_info (parser, sym_table->offset, i);
addr = st_value (parser, sym_table->offset, i);
shndx = st_shndx (parser, sym_table->offset, i);
#if 0
g_print ("read symbol: %s (section: %d)\n", get_string_indirct (parser->parser,
parser->sym_format, "st_name",
str_table->offset),
shndx);
#endif
if (addr != 0 &&
shndx < parser->n_sections &&
parser->sections[shndx] == parser->text_section &&
(info & 0xf) == STT_FUNC &&
((info >> 4) == STB_GLOBAL ||
(info >> 4) == STB_LOCAL ||
(info >> 4) == STB_WEAK))
{
parser->symbols[n_symbols].address = addr;
parser->symbols[n_symbols].table = sym_table->offset;
parser->symbols[n_symbols].offset = i;
n_symbols++;
#if 0
g_print (" symbol: %s: %lx\n",
get_string_indirect (parser->parser,
parser->sym_format, "st_name",
str_table->offset),
addr - parser->text_section->load_address);
g_print (" sym %d in %p (info: %d:%d) (func:global %d:%d)\n",
addr, parser, info & 0xf, info >> 4, STT_FUNC, STB_GLOBAL);
#endif
}
else if (addr != 0)
{
#if 0
g_print (" rejecting %d in %p (info: %d:%d) (func:global %d:%d)\n",
addr, parser, info & 0xf, info >> 4, STT_FUNC, STB_GLOBAL);
#endif
}
}
parser->sym_strings = str_table->offset;
parser->n_symbols = n_symbols;
/* Allocate space for at least one symbol, so that parser->symbols will be
* non-NULL. If it ends up being NULL, we will be parsing the file over and
* over.
*/
parser->symbols = g_renew (ElfSym, parser->symbols, parser->n_symbols + 1);
qsort (parser->symbols, parser->n_symbols, sizeof (ElfSym), compare_sym);
}
static void
read_symbols (ElfParser *parser)
{
const Section *symtab = find_section (parser, ".symtab", SHT_SYMTAB);
const Section *strtab = find_section (parser, ".strtab", SHT_STRTAB);
const Section *dynsym = find_section (parser, ".dynsym", SHT_DYNSYM);
const Section *dynstr = find_section (parser, ".dynstr", SHT_STRTAB);
if (symtab && strtab)
{
#if 0
g_print ("reading symbol table of %s\n", parser->filename);
#endif
read_table (parser, symtab, strtab);
}
else if (dynsym && dynstr)
{
#if 0
g_print ("reading dynamic symbol table of %s\n", parser->filename);
#endif
read_table (parser, dynsym, dynstr);
}
else
{
/* To make sure parser->symbols is non-NULL */
parser->n_symbols = 0;
parser->symbols = g_new (ElfSym, 1);
}
}
static ElfSym *
do_lookup (ElfSym *symbols,
gulong address,
int first,
int last)
{
if (address >= symbols[last].address)
{
return &(symbols[last]);
}
else if (last - first < 3)
{
while (last >= first)
{
if (address >= symbols[last].address)
return &(symbols[last]);
last--;
}
return NULL;
}
else
{
int mid = (first + last) / 2;
if (symbols[mid].address > address)
return do_lookup (symbols, address, first, mid);
else
return do_lookup (symbols, address, mid, last);
}
}
/* Address should be given in 'offset into text segment' */
const ElfSym *
elf_parser_lookup_symbol (ElfParser *parser,
gulong address)
{
const ElfSym *result;
if (!parser->symbols)
{
#if 0
g_print ("reading symbols at %p\n", parser);
#endif
read_symbols (parser);
}
if (parser->n_symbols == 0)
return NULL;
if (!parser->text_section)
return NULL;
address += parser->text_section->load_address;
#if 0
g_print ("elf: the address we are looking up is %p\n", address);
#endif
result = do_lookup (parser->symbols, address, 0, parser->n_symbols - 1);
#if 0
if (result)
{
g_print (" elf: found %s at %lx\n", elf_parser_get_sym_name (parser, result), result->address);
}
else
{
g_print ("elf: not found\n");
}
#endif
if (result)
{
gulong size = st_size (parser, result->table, result->offset);
if (size > 0 && result->address + size <= address)
{
#if 0
g_print (" elf: ends at %lx, so rejecting\n",
result->address + size);
#endif
result = NULL;
}
}
if (result)
{
/* Reject the symbols if the address is outside the text section */
if (address > parser->text_section->load_address + parser->text_section->size)
result = NULL;
}
return result;
}
gulong
elf_parser_get_text_offset (ElfParser *parser)
{
g_return_val_if_fail (parser != NULL, (gulong)-1);
if (!parser->text_section)
return (gulong)-1;
return parser->text_section->offset;
}
static gchar *
make_hex_string (const guchar *data, int n_bytes)
{
static const char hex_digits[] = {
'0', '1', '2', '3', '4', '5', '6', '7',
'8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};
GString *string = g_string_new (NULL);
int i;
for (i = 0; i < n_bytes; ++i)
{
char c = data[i];
g_string_append_c (string, hex_digits[(c & 0xf0) >> 4]);
g_string_append_c (string, hex_digits[(c & 0x0f)]);
}
return g_string_free (string, FALSE);
}
const gchar *
elf_parser_get_build_id (ElfParser *parser)
{
if (!parser->checked_build_id)
{
const Section *build_id =
find_section (parser, ".note.gnu.build-id", SHT_NOTE);
guint64 name_size;
guint64 desc_size;
guint64 type;
const char *name;
guint64 offset;
parser->checked_build_id = TRUE;
if (!build_id)
return NULL;
offset = build_id->offset;
name_size = GET_FIELD (parser, offset, Nhdr, 0, n_namesz);
desc_size = GET_FIELD (parser, offset, Nhdr, 0, n_descsz);
type = GET_FIELD (parser, offset, Nhdr, 0, n_type);
offset += GET_SIZE (parser, Nhdr);
name = (char *)(parser->data + offset);
if (strncmp (name, ELF_NOTE_GNU, name_size) != 0 || type != NT_GNU_BUILD_ID)
return NULL;
offset += strlen (name);
offset = (offset + 3) & (~0x3);
parser->build_id = make_hex_string (parser->data + offset, desc_size);
}
return parser->build_id;
}
const char *
elf_parser_get_debug_link (ElfParser *parser,
guint32 *crc32)
{
guint64 offset;
const Section *debug_link = find_section (parser, ".gnu_debuglink",
SHT_PROGBITS);
const gchar *result;
if (!debug_link)
return NULL;
offset = debug_link->offset;
result = (char *)(parser->data + offset);
if (crc32)
{
int len = strlen (result) + 1;
offset = (offset + len + 3) & ~0x3;
*crc32 = GET_UINT32 (parser, offset);
}
return result;
}
static const guchar *
get_section (ElfParser *parser,
const char *name)
{
const Section *section = find_section (parser, name, SHT_PROGBITS);
if (section)
return parser->data + section->offset;
else
return NULL;
}
const guchar *
elf_parser_get_eh_frame (ElfParser *parser)
{
return get_section (parser, ".eh_frame");
}
const guchar *
elf_parser_get_debug_frame (ElfParser *parser)
{
return get_section (parser, ".debug_frame");
}
const char *
elf_parser_get_sym_name (ElfParser *parser,
const ElfSym *sym)
{
g_return_val_if_fail (parser != NULL, NULL);
return (char *)(parser->data + parser->sym_strings +
st_name (parser, sym->table, sym->offset));
}
gboolean
elf_parser_owns_symbol (ElfParser *parser,
const ElfSym *sym)
{
ElfSym *first, *last;
if (!parser->n_symbols)
return FALSE;
first = parser->symbols;
last = parser->symbols + parser->n_symbols - 1;
return first <= sym && sym <= last;
}
gulong
elf_parser_get_sym_address (ElfParser *parser,
const ElfSym *sym)
{
return sym->address - parser->text_section->load_address;
}
void
elf_parser_get_sym_address_range (ElfParser *parser,
const ElfSym *sym,
gulong *begin,
gulong *end)
{
*begin = sym->address - parser->text_section->load_address;
*end = *begin + st_size (parser, sym->table, sym->offset);
}
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