bfd/libelf.h

   1 /* BFD back-end data structures for ELF files.
   2    Copyright (C) 1992, 1993 Free Software Foundation, Inc.
   3    Written by Cygnus Support.
   4
   5 This file is part of BFD, the Binary File Descriptor library.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #ifndef _LIBELF_H_
  22 #define _LIBELF_H_ 1
  23
  24 #include "elf/common.h"
  25 #include "elf/internal.h"
  26 #include "elf/external.h"
  27
  28 /* If size isn't specified as 64 or 32, NAME macro should fail.  */
  29 #ifndef NAME
  30 #if ARCH_SIZE==64
  31 #define NAME(x,y) CAT4(x,64,_,y)
  32 #endif
  33 #if ARCH_SIZE==32
  34 #define NAME(x,y) CAT4(x,32,_,y)
  35 #endif
  36 #endif
  37
  38 #ifndef NAME
  39 #define NAME(x,y) CAT4(x,NOSIZE,_,y)
  40 #endif
  41
  42 #define ElfNAME(X)      NAME(Elf,X)
  43 #define elfNAME(X)      NAME(elf,X)
  44
  45 /* Information held for an ELF symbol.  The first field is the
  46    corresponding asymbol.  Every symbol is an ELF file is actually a
  47    pointer to this structure, although it is often handled as a
  48    pointer to an asymbol.  */
  49
  50 typedef struct
  51 {
  52   /* The BFD symbol.  */
  53   asymbol symbol;
  54   /* ELF symbol information.  */
  55   Elf_Internal_Sym internal_elf_sym;
  56   /* Backend specific information.  */
  57   union
  58     {
  59       unsigned int hppa_arg_reloc;
  60       PTR mips_extr;
  61       PTR any;
  62     }
  63   tc_data;
  64 } elf_symbol_type;
  65
  66 /* Constant information held for an ELF backend.  */
  67
  68 struct elf_backend_data
  69 {
  70   /* Whether the backend uses REL or RELA relocations.  FIXME: some
  71      ELF backends use both.  When we need to support one, this whole
  72      approach will need to be changed.  */
  73   int use_rela_p;
  74
  75   /* Whether this backend is 64 bits or not.  FIXME: Who cares?  */
  76   int elf_64_p;
  77
  78   /* The architecture for this backend.  */
  79   enum bfd_architecture arch;
  80
  81   /* The ELF machine code (EM_xxxx) for this backend.  */
  82   int elf_machine_code;
  83
  84   /* The maximum page size for this backend.  */
  85   bfd_vma maxpagesize;
  86
  87   /* A function to translate an ELF RELA relocation to a BFD arelent
  88      structure.  */
  89   void (*elf_info_to_howto) PARAMS ((bfd *, arelent *,
  90                                      Elf_Internal_Rela *));
  91
  92   /* A function to translate an ELF REL relocation to a BFD arelent
  93      structure.  */
  94   void (*elf_info_to_howto_rel) PARAMS ((bfd *, arelent *,
  95                                          Elf_Internal_Rel *));
  96
  97   /* A function to determine whether a symbol is global when
  98      partitioning the symbol table into local and global symbols.
  99      This should be NULL for most targets, in which case the correct
 100      thing will be done.  MIPS ELF, at least on the Irix 5, has
 101      special requirements.  */
 102   boolean (*elf_backend_sym_is_global) PARAMS ((bfd *, asymbol *));
 103
 104   /* The remaining functions are hooks which are called only if they
 105      are not NULL.  */
 106
 107   /* A function to permit a backend specific check on whether a
 108      particular BFD format is relevant for an object file, and to
 109      permit the backend to set any global information it wishes.  When
 110      this is called elf_elfheader is set, but anything else should be
 111      used with caution.  If this returns false, the check_format
 112      routine will return a wrong_format error.  */
 113   boolean (*elf_backend_object_p) PARAMS ((bfd *));
 114
 115   /* A function to do additional symbol processing when reading the
 116      ELF symbol table.  This is where any processor-specific special
 117      section indices are handled.  */
 118   void (*elf_backend_symbol_processing) PARAMS ((bfd *, asymbol *));
 119
 120   /* A function to do additional symbol processing after reading the
 121      entire ELF symbol table.  */
 122   boolean (*elf_backend_symbol_table_processing) PARAMS ((bfd *,
 123                                                           elf_symbol_type *,
 124                                                           int));
 125
 126   /* A function to do additional processing on the ELF section header
 127      just before writing it out.  This is used to set the flags and
 128      type fields for some sections, or to actually write out data for
 129      unusual sections.  */
 130   boolean (*elf_backend_section_processing) PARAMS ((bfd *,
 131                                                      Elf32_Internal_Shdr *));
 132
 133   /* A function to handle unusual section types when creating BFD
 134      sections from ELF sections.  */
 135   boolean (*elf_backend_section_from_shdr) PARAMS ((bfd *,
 136                                                     Elf32_Internal_Shdr *,
 137                                                     char *));
 138
 139   /* A function to set up the ELF section header for a BFD section in
 140      preparation for writing it out.  This is where the flags and type
 141      fields are set for unusual sections.  */
 142   boolean (*elf_backend_fake_sections) PARAMS ((bfd *, Elf32_Internal_Shdr *,
 143                                                 asection *));
 144
 145   /* A function to get the ELF section index for a BFD section.  If
 146      this returns true, the section was found.  If it is a normal ELF
 147      section, *RETVAL should be left unchanged.  If it is not a normal
 148      ELF section *RETVAL should be set to the SHN_xxxx index.  */
 149   boolean (*elf_backend_section_from_bfd_section)
 150     PARAMS ((bfd *, Elf32_Internal_Shdr *, asection *, int *retval));
 151
 152   /* A function to do any final processing needed for the ELF file
 153      before writing it out.  */
 154   void (*elf_backend_final_write_processing) PARAMS ((bfd *));
 155
 156   /* The swapping table to use when dealing with ECOFF information.
 157      Used for the MIPS ELF .mdebug section.  */
 158   const struct ecoff_debug_swap *elf_backend_ecoff_debug_swap;
 159 };
 160
 161 struct elf_sym_extra
 162 {
 163   int elf_sym_num;              /* sym# after locals/globals are reordered */
 164 };
 165
 166 typedef struct elf_sym_extra Elf_Sym_Extra;
 167
 168 struct bfd_elf_section_data {
 169   Elf_Internal_Shdr this_hdr;
 170   Elf_Internal_Shdr rel_hdr;
 171   int this_idx, rel_idx;
 172 };
 173 #define elf_section_data(sec)  ((struct bfd_elf_section_data*)sec->used_by_bfd)
 174 #define shdr_name(abfd,shdr)    (elf_shstrtab (abfd)->tab + (shdr)->sh_name)
 175
 176 #define get_elf_backend_data(abfd) \
 177   ((struct elf_backend_data *) (abfd)->xvec->backend_data)
 178
 179 struct strtab
 180 {
 181   char *tab;
 182   int nentries;
 183   int length;
 184 };
 185
 186 /* Some private data is stashed away for future use using the tdata pointer
 187    in the bfd structure.  */
 188
 189 struct elf_obj_tdata
 190 {
 191   Elf_Internal_Ehdr elf_header[1];      /* Actual data, but ref like ptr */
 192   Elf_Internal_Shdr **elf_sect_ptr;
 193   Elf_Internal_Phdr *phdr;
 194   struct strtab *strtab_ptr;
 195   int num_locals;
 196   int num_globals;
 197   Elf_Internal_Sym *internal_syms;
 198   elf_symbol_type *symbols;     /* elf_symbol_type */
 199   Elf_Sym_Extra *sym_extra;
 200   asymbol **section_syms;       /* STT_SECTION symbols for each section */
 201   int num_section_syms;         /* number of section_syms allocated */
 202   Elf_Internal_Shdr symtab_hdr;
 203   Elf_Internal_Shdr shstrtab_hdr;
 204   Elf_Internal_Shdr strtab_hdr;
 205   int symtab_section, shstrtab_section, strtab_section;
 206   file_ptr next_file_pos;
 207   void *prstatus;               /* The raw /proc prstatus structure */
 208   void *prpsinfo;               /* The raw /proc prpsinfo structure */
 209   bfd_vma gp;                   /* The gp value (MIPS only, for now) */
 210   int gp_size;                  /* The gp size (MIPS only, for now) */
 211 };
 212
 213 #define elf_tdata(bfd)          ((bfd) -> tdata.elf_obj_data)
 214 #define elf_elfheader(bfd)      (elf_tdata(bfd) -> elf_header)
 215 #define elf_elfsections(bfd)    (elf_tdata(bfd) -> elf_sect_ptr)
 216 #define elf_shstrtab(bfd)       (elf_tdata(bfd) -> strtab_ptr)
 217 #define elf_onesymtab(bfd)      (elf_tdata(bfd) -> symtab_section)
 218 #define elf_num_locals(bfd)     (elf_tdata(bfd) -> num_locals)
 219 #define elf_num_globals(bfd)    (elf_tdata(bfd) -> num_globals)
 220 #define elf_sym_extra(bfd)      (elf_tdata(bfd) -> sym_extra)
 221 #define elf_section_syms(bfd)   (elf_tdata(bfd) -> section_syms)
 222 #define elf_num_section_syms(bfd) (elf_tdata(bfd) -> num_section_syms)
 223 #define core_prpsinfo(bfd)      (elf_tdata(bfd) -> prpsinfo)
 224 #define core_prstatus(bfd)      (elf_tdata(bfd) -> prstatus)
 225 #define obj_symbols(bfd)        (elf_tdata(bfd) -> symbols)
 226 #define obj_internal_syms(bfd)  (elf_tdata(bfd) -> internal_syms)
 227 #define elf_gp(bfd)             (elf_tdata(bfd) -> gp)
 228 #define elf_gp_size(bfd)        (elf_tdata(bfd) -> gp_size)
 229
 230 extern char * elf_string_from_elf_section PARAMS ((bfd *, unsigned, unsigned));
 231 extern char * elf_get_str_section PARAMS ((bfd *, unsigned));
 232
 233 #define bfd_elf32_mkobject      bfd_elf_mkobject
 234 #define bfd_elf64_mkobject      bfd_elf_mkobject
 235 #define elf_mkobject            bfd_elf_mkobject
 236
 237 extern unsigned long bfd_elf_hash PARAMS ((CONST unsigned char *));
 238
 239 extern bfd_reloc_status_type bfd_elf_generic_reloc PARAMS ((bfd *,
 240                                                             arelent *,
 241                                                             asymbol *,
 242                                                             PTR,
 243                                                             asection *,
 244                                                             bfd *,
 245                                                             char **));
 246 extern boolean bfd_elf_mkobject PARAMS ((bfd *));
 247 extern Elf_Internal_Shdr *bfd_elf_find_section PARAMS ((bfd *, char *));
 248
 249 extern boolean bfd_elf32_write_object_contents PARAMS ((bfd *));
 250 extern boolean bfd_elf64_write_object_contents PARAMS ((bfd *));
 251
 252 extern bfd_target *bfd_elf32_object_p PARAMS ((bfd *));
 253 extern bfd_target *bfd_elf32_core_file_p PARAMS ((bfd *));
 254 extern char *bfd_elf32_core_file_failing_command PARAMS ((bfd *));
 255 extern int bfd_elf32_core_file_failing_signal PARAMS ((bfd *));
 256 extern boolean bfd_elf32_core_file_matches_executable_p PARAMS ((bfd *,
 257                                                                  bfd *));
 258 extern boolean bfd_elf32_set_section_contents PARAMS ((bfd *, sec_ptr, PTR,
 259                                                        file_ptr,
 260                                                        bfd_size_type));
 261
 262 extern unsigned int bfd_elf32_get_symtab_upper_bound PARAMS ((bfd *));
 263 extern unsigned int bfd_elf32_get_symtab PARAMS ((bfd *, asymbol **));
 264 extern unsigned int bfd_elf32_get_reloc_upper_bound PARAMS ((bfd *, sec_ptr));
 265 extern unsigned int bfd_elf32_canonicalize_reloc PARAMS ((bfd *, sec_ptr,
 266                                                           arelent **,
 267                                                           asymbol **));
 268 extern asymbol *bfd_elf32_make_empty_symbol PARAMS ((bfd *));
 269 extern void bfd_elf32_print_symbol PARAMS ((bfd *, PTR, asymbol *,
 270                                             bfd_print_symbol_type));
 271 extern void bfd_elf32_get_symbol_info PARAMS ((bfd *, asymbol *,
 272                                                symbol_info *));
 273 extern alent *bfd_elf32_get_lineno PARAMS ((bfd *, asymbol *));
 274 extern boolean bfd_elf32_set_arch_mach PARAMS ((bfd *, enum bfd_architecture,
 275                                                 unsigned long));
 276 extern boolean bfd_elf32_find_nearest_line PARAMS ((bfd *, asection *,
 277                                                     asymbol **,
 278                                                     bfd_vma, CONST char **,
 279                                                     CONST char **,
 280                                                     unsigned int *));
 281 extern int bfd_elf32_sizeof_headers PARAMS ((bfd *, boolean));
 282 extern void bfd_elf32__write_relocs PARAMS ((bfd *, asection *, PTR));
 283 extern boolean bfd_elf32_new_section_hook PARAMS ((bfd *, asection *));
 284
 285 /* If the target doesn't have reloc handling written yet:  */
 286 extern void bfd_elf32_no_info_to_howto PARAMS ((bfd *, arelent *,
 287                                                 Elf32_Internal_Rela *));
 288
 289 extern bfd_target *bfd_elf64_object_p PARAMS ((bfd *));
 290 extern bfd_target *bfd_elf64_core_file_p PARAMS ((bfd *));
 291 extern char *bfd_elf64_core_file_failing_command PARAMS ((bfd *));
 292 extern int bfd_elf64_core_file_failing_signal PARAMS ((bfd *));
 293 extern boolean bfd_elf64_core_file_matches_executable_p PARAMS ((bfd *,
 294                                                                  bfd *));
 295 extern boolean bfd_elf64_set_section_contents PARAMS ((bfd *, sec_ptr, PTR,
 296                                                        file_ptr,
 297                                                        bfd_size_type));
 298
 299 extern unsigned int bfd_elf64_get_symtab_upper_bound PARAMS ((bfd *));
 300 extern unsigned int bfd_elf64_get_symtab PARAMS ((bfd *, asymbol **));
 301 extern unsigned int bfd_elf64_get_reloc_upper_bound PARAMS ((bfd *, sec_ptr));
 302 extern unsigned int bfd_elf64_canonicalize_reloc PARAMS ((bfd *, sec_ptr,
 303                                                           arelent **,
 304                                                           asymbol **));
 305 extern asymbol *bfd_elf64_make_empty_symbol PARAMS ((bfd *));
 306 extern void bfd_elf64_print_symbol PARAMS ((bfd *, PTR, asymbol *,
 307                                             bfd_print_symbol_type));
 308 extern void bfd_elf64_get_symbol_info PARAMS ((bfd *, asymbol *,
 309                                                symbol_info *));
 310 extern alent *bfd_elf64_get_lineno PARAMS ((bfd *, asymbol *));
 311 extern boolean bfd_elf64_set_arch_mach PARAMS ((bfd *, enum bfd_architecture,
 312                                                 unsigned long));
 313 extern boolean bfd_elf64_find_nearest_line PARAMS ((bfd *, asection *,
 314                                                     asymbol **,
 315                                                     bfd_vma, CONST char **,
 316                                                     CONST char **,
 317                                                     unsigned int *));
 318 extern int bfd_elf64_sizeof_headers PARAMS ((bfd *, boolean));
 319 extern void bfd_elf64__write_relocs PARAMS ((bfd *, asection *, PTR));
 320 extern boolean bfd_elf64_new_section_hook PARAMS ((bfd *, asection *));
 321
 322 /* If the target doesn't have reloc handling written yet:  */
 323 extern void bfd_elf64_no_info_to_howto PARAMS ((bfd *, arelent *,
 324                                                 Elf64_Internal_Rela *));
 325
 326 #endif /* _LIBELF_H_ */