LXR linux/tools/objtool/elf.h

   1/*
   2 * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public License
   6 * as published by the Free Software Foundation; either version 2
   7 * of the License, or (at your option) any later version.
   8 *
   9 * This program is distributed in the hope that it will be useful,
  10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 * GNU General Public License for more details.
  13 *
  14 * You should have received a copy of the GNU General Public License
  15 * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16 */
  17
  18#ifndef _OBJTOOL_ELF_H
  19#define _OBJTOOL_ELF_H
  20
  21#include <stdio.h>
  22#include <gelf.h>
  23#include <linux/list.h>
  24#include <linux/hashtable.h>
  25
  26#ifdef LIBELF_USE_DEPRECATED
  27# define elf_getshdrnum    elf_getshnum
  28# define elf_getshdrstrndx elf_getshstrndx
  29#endif
  30
  31/*
  32 * Fallback for systems without this "read, mmaping if possible" cmd.
  33 */
  34#ifndef ELF_C_READ_MMAP
  35#define ELF_C_READ_MMAP ELF_C_READ
  36#endif
  37
  38struct section {
  39        struct list_head list;
  40        GElf_Shdr sh;
  41        struct list_head symbol_list;
  42        DECLARE_HASHTABLE(symbol_hash, 8);
  43        struct list_head rela_list;
  44        DECLARE_HASHTABLE(rela_hash, 16);
  45        struct section *base, *rela;
  46        struct symbol *sym;
  47        Elf_Data *data;
  48        char *name;
  49        int idx;
  50        unsigned int len;
  51        bool changed, text;
  52};
  53
  54struct symbol {
  55        struct list_head list;
  56        struct hlist_node hash;
  57        GElf_Sym sym;
  58        struct section *sec;
  59        char *name;
  60        unsigned int idx;
  61        unsigned char bind, type;
  62        unsigned long offset;
  63        unsigned int len;
  64};
  65
  66struct rela {
  67        struct list_head list;
  68        struct hlist_node hash;
  69        GElf_Rela rela;
  70        struct symbol *sym;
  71        unsigned int type;
  72        unsigned long offset;
  73        int addend;
  74};
  75
  76struct elf {
  77        Elf *elf;
  78        GElf_Ehdr ehdr;
  79        int fd;
  80        char *name;
  81        struct list_head sections;
  82        DECLARE_HASHTABLE(rela_hash, 16);
  83};
  84
  85
  86struct elf *elf_open(const char *name, int flags);
  87struct section *find_section_by_name(struct elf *elf, const char *name);
  88struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset);
  89struct symbol *find_symbol_containing(struct section *sec, unsigned long offset);
  90struct rela *find_rela_by_dest(struct section *sec, unsigned long offset);
  91struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset,
  92                                     unsigned int len);
  93struct symbol *find_containing_func(struct section *sec, unsigned long offset);
  94struct section *elf_create_section(struct elf *elf, const char *name, size_t
  95                                   entsize, int nr);
  96struct section *elf_create_rela_section(struct elf *elf, struct section *base);
  97int elf_rebuild_rela_section(struct section *sec);
  98int elf_write(struct elf *elf);
  99void elf_close(struct elf *elf);
 100
 101#define for_each_sec(file, sec)                                         \
 102        list_for_each_entry(sec, &file->elf->sections, list)
 103
 104#endif /* _OBJTOOL_ELF_H */
 105