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 bfd_error_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 beginning processing needed for the ELF file
 153      before building the ELF headers and computing file positions.  */
 154   void (*elf_backend_begin_write_processing) PARAMS ((bfd *));
 155
 156   /* A function to do any final processing needed for the ELF file
 157      before writing it out.  */
 158   void (*elf_backend_final_write_processing) PARAMS ((bfd *));
 159
 160   /* The swapping table to use when dealing with ECOFF information.
 161      Used for the MIPS ELF .mdebug section.  */
 162   const struct ecoff_debug_swap *elf_backend_ecoff_debug_swap;
 163 };
 164
 165 struct elf_sym_extra
 166 {
 167   int elf_sym_num;              /* sym# after locals/globals are reordered */
 168 };
 169
 170 typedef struct elf_sym_extra Elf_Sym_Extra;
 171
 172 struct bfd_elf_section_data {
 173   Elf_Internal_Shdr this_hdr;
 174   Elf_Internal_Shdr rel_hdr;
 175   int this_idx, rel_idx;
 176 };
 177 #define elf_section_data(sec)  ((struct bfd_elf_section_data*)sec->used_by_bfd)
 178 #define shdr_name(abfd,shdr)    (elf_shstrtab (abfd)->tab + (shdr)->sh_name)
 179
 180 #define get_elf_backend_data(abfd) \
 181   ((struct elf_backend_data *) (abfd)->xvec->backend_data)
 182
 183 struct strtab
 184 {
 185   char *tab;
 186   int nentries;
 187   int length;
 188 };
 189
 190 /* Some private data is stashed away for future use using the tdata pointer
 191    in the bfd structure.  */
 192
 193 struct elf_obj_tdata
 194 {
 195   Elf_Internal_Ehdr elf_header[1];      /* Actual data, but ref like ptr */
 196   Elf_Internal_Shdr **elf_sect_ptr;
 197   Elf_Internal_Phdr *phdr;
 198   struct strtab *strtab_ptr;
 199   int num_locals;
 200   int num_globals;
 201   Elf_Internal_Sym *internal_syms;
 202   elf_symbol_type *symbols;     /* elf_symbol_type */
 203   Elf_Sym_Extra *sym_extra;
 204   asymbol **section_syms;       /* STT_SECTION symbols for each section */
 205   int num_section_syms;         /* number of section_syms allocated */
 206   Elf_Internal_Shdr symtab_hdr;
 207   Elf_Internal_Shdr shstrtab_hdr;
 208   Elf_Internal_Shdr strtab_hdr;
 209   int symtab_section, shstrtab_section, strtab_section;
 210   file_ptr next_file_pos;
 211   void *prstatus;               /* The raw /proc prstatus structure */
 212   void *prpsinfo;               /* The raw /proc prpsinfo structure */
 213   bfd_vma gp;                   /* The gp value (MIPS only, for now) */
 214   int gp_size;                  /* The gp size (MIPS only, for now) */
 215 };
 216
 217 #define elf_tdata(bfd)          ((bfd) -> tdata.elf_obj_data)
 218 #define elf_elfheader(bfd)      (elf_tdata(bfd) -> elf_header)
 219 #define elf_elfsections(bfd)    (elf_tdata(bfd) -> elf_sect_ptr)
 220 #define elf_shstrtab(bfd)       (elf_tdata(bfd) -> strtab_ptr)
 221 #define elf_onesymtab(bfd)      (elf_tdata(bfd) -> symtab_section)
 222 #define elf_num_locals(bfd)     (elf_tdata(bfd) -> num_locals)
 223 #define elf_num_globals(bfd)    (elf_tdata(bfd) -> num_globals)
 224 #define elf_sym_extra(bfd)      (elf_tdata(bfd) -> sym_extra)
 225 #define elf_section_syms(bfd)   (elf_tdata(bfd) -> section_syms)
 226 #define elf_num_section_syms(bfd) (elf_tdata(bfd) -> num_section_syms)
 227 #define core_prpsinfo(bfd)      (elf_tdata(bfd) -> prpsinfo)
 228 #define core_prstatus(bfd)      (elf_tdata(bfd) -> prstatus)
 229 #define obj_symbols(bfd)        (elf_tdata(bfd) -> symbols)
 230 #define obj_internal_syms(bfd)  (elf_tdata(bfd) -> internal_syms)
 231 #define elf_gp(bfd)             (elf_tdata(bfd) -> gp)
 232 #define elf_gp_size(bfd)        (elf_tdata(bfd) -> gp_size)
 233
 234 extern char * elf_string_from_elf_section PARAMS ((bfd *, unsigned, unsigned));
 235 extern char * elf_get_str_section PARAMS ((bfd *, unsigned));
 236
 237 #define bfd_elf32_mkobject      bfd_elf_mkobject
 238 #define bfd_elf64_mkobject      bfd_elf_mkobject
 239 #define elf_mkobject            bfd_elf_mkobject
 240
 241 extern unsigned long bfd_elf_hash PARAMS ((CONST unsigned char *));
 242
 243 extern bfd_reloc_status_type bfd_elf_generic_reloc PARAMS ((bfd *,
 244                                                             arelent *,
 245                                                             asymbol *,
 246                                                             PTR,
 247                                                             asection *,
 248                                                             bfd *,
 249                                                             char **));
 250 extern boolean bfd_elf_mkobject PARAMS ((bfd *));
 251 extern Elf_Internal_Shdr *bfd_elf_find_section PARAMS ((bfd *, char *));
 252
 253 extern boolean bfd_elf32_write_object_contents PARAMS ((bfd *));
 254 extern boolean bfd_elf64_write_object_contents PARAMS ((bfd *));
 255
 256 extern bfd_target *bfd_elf32_object_p PARAMS ((bfd *));
 257 extern bfd_target *bfd_elf32_core_file_p PARAMS ((bfd *));
 258 extern char *bfd_elf32_core_file_failing_command PARAMS ((bfd *));
 259 extern int bfd_elf32_core_file_failing_signal PARAMS ((bfd *));
 260 extern boolean bfd_elf32_core_file_matches_executable_p PARAMS ((bfd *,
 261                                                                  bfd *));
 262 extern boolean bfd_elf32_set_section_contents PARAMS ((bfd *, sec_ptr, PTR,
 263                                                        file_ptr,
 264                                                        bfd_size_type));
 265
 266 extern long bfd_elf32_get_symtab_upper_bound PARAMS ((bfd *));
 267 extern long bfd_elf32_get_symtab PARAMS ((bfd *, asymbol **));
 268 extern long bfd_elf32_get_reloc_upper_bound PARAMS ((bfd *, sec_ptr));
 269 extern long bfd_elf32_canonicalize_reloc PARAMS ((bfd *, sec_ptr,
 270                                                   arelent **, asymbol **));
 271 extern asymbol *bfd_elf32_make_empty_symbol PARAMS ((bfd *));
 272 extern void bfd_elf32_print_symbol PARAMS ((bfd *, PTR, asymbol *,
 273                                             bfd_print_symbol_type));
 274 extern void bfd_elf32_get_symbol_info PARAMS ((bfd *, asymbol *,
 275                                                symbol_info *));
 276 extern alent *bfd_elf32_get_lineno PARAMS ((bfd *, asymbol *));
 277 extern boolean bfd_elf32_set_arch_mach PARAMS ((bfd *, enum bfd_architecture,
 278                                                 unsigned long));
 279 extern boolean bfd_elf32_find_nearest_line PARAMS ((bfd *, asection *,
 280                                                     asymbol **,
 281                                                     bfd_vma, CONST char **,
 282                                                     CONST char **,
 283                                                     unsigned int *));
 284 extern int bfd_elf32_sizeof_headers PARAMS ((bfd *, boolean));
 285 extern void bfd_elf32__write_relocs PARAMS ((bfd *, asection *, PTR));
 286 extern boolean bfd_elf32_new_section_hook PARAMS ((bfd *, asection *));
 287
 288 /* If the target doesn't have reloc handling written yet:  */
 289 extern void bfd_elf32_no_info_to_howto PARAMS ((bfd *, arelent *,
 290                                                 Elf32_Internal_Rela *));
 291
 292 extern bfd_target *bfd_elf64_object_p PARAMS ((bfd *));
 293 extern bfd_target *bfd_elf64_core_file_p PARAMS ((bfd *));
 294 extern char *bfd_elf64_core_file_failing_command PARAMS ((bfd *));
 295 extern int bfd_elf64_core_file_failing_signal PARAMS ((bfd *));
 296 extern boolean bfd_elf64_core_file_matches_executable_p PARAMS ((bfd *,
 297                                                                  bfd *));
 298 extern boolean bfd_elf64_set_section_contents PARAMS ((bfd *, sec_ptr, PTR,
 299                                                        file_ptr,
 300                                                        bfd_size_type));
 301
 302 extern long bfd_elf64_get_symtab_upper_bound PARAMS ((bfd *));
 303 extern long bfd_elf64_get_symtab PARAMS ((bfd *, asymbol **));
 304 extern long bfd_elf64_get_reloc_upper_bound PARAMS ((bfd *, sec_ptr));
 305 extern long bfd_elf64_canonicalize_reloc PARAMS ((bfd *, sec_ptr,
 306                                                   arelent **, asymbol **));
 307 extern asymbol *bfd_elf64_make_empty_symbol PARAMS ((bfd *));
 308 extern void bfd_elf64_print_symbol PARAMS ((bfd *, PTR, asymbol *,
 309                                             bfd_print_symbol_type));
 310 extern void bfd_elf64_get_symbol_info PARAMS ((bfd *, asymbol *,
 311                                                symbol_info *));
 312 extern alent *bfd_elf64_get_lineno PARAMS ((bfd *, asymbol *));
 313 extern boolean bfd_elf64_set_arch_mach PARAMS ((bfd *, enum bfd_architecture,
 314                                                 unsigned long));
 315 extern boolean bfd_elf64_find_nearest_line PARAMS ((bfd *, asection *,
 316                                                     asymbol **,
 317                                                     bfd_vma, CONST char **,
 318                                                     CONST char **,
 319                                                     unsigned int *));
 320 extern int bfd_elf64_sizeof_headers PARAMS ((bfd *, boolean));
 321 extern void bfd_elf64__write_relocs PARAMS ((bfd *, asection *, PTR));
 322 extern boolean bfd_elf64_new_section_hook PARAMS ((bfd *, asection *));
 323
 324 /* If the target doesn't have reloc handling written yet:  */
 325 extern void bfd_elf64_no_info_to_howto PARAMS ((bfd *, arelent *,
 326                                                 Elf64_Internal_Rela *));
 327
 328 #endif /* _LIBELF_H_ */