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 any;
  61     }
  62   tc_data;
  63 } elf_symbol_type;
  64
  65 /* Constant information held for an ELF backend.  */
  66
  67 struct elf_backend_data
  68 {
  69   /* Whether the backend uses REL or RELA relocations.  FIXME: some
  70      ELF backends use both.  When we need to support one, this whole
  71      approach will need to be changed.  */
  72   int use_rela_p;
  73
  74   /* Whether this backend is 64 bits or not.  FIXME: Who cares?  */
  75   int elf_64_p;
  76
  77   /* The architecture for this backend.  */
  78   enum bfd_architecture arch;
  79
  80   /* The ELF machine code (EM_xxxx) for this backend.  */
  81   int elf_machine_code;
  82
  83   /* The maximum page size for this backend.  */
  84   bfd_vma maxpagesize;
  85
  86   /* A function to translate an ELF RELA relocation to a BFD arelent
  87      structure.  */
  88   void (*elf_info_to_howto) PARAMS ((bfd *, arelent *,
  89                                      Elf_Internal_Rela *));
  90
  91   /* A function to translate an ELF REL relocation to a BFD arelent
  92      structure.  */
  93   void (*elf_info_to_howto_rel) PARAMS ((bfd *, arelent *,
  94                                          Elf_Internal_Rel *));
  95
  96   /* The remaining functions are hooks which are called only if they
  97      are not NULL.  */
  98
  99   /* A function to permit a backend specific check on whether a
 100      particular BFD format is relevant for an object file, and to
 101      permit the backend to set any global information it wishes.  When
 102      this is called elf_elfheader is set, but anything else should be
 103      used with caution.  If this returns false, the check_format
 104      routine will return a wrong_format error.  */
 105   boolean (*elf_backend_object_p) PARAMS ((bfd *));
 106
 107   /* A function to do additional symbol processing when reading the
 108      ELF symbol table.  This is where any processor-specific special
 109      section indices are handled.  */
 110   void (*elf_backend_symbol_processing) PARAMS ((bfd *, asymbol *));
 111
 112   /* A function to do additional symbol processing after reading the
 113      entire ELF symbol table.  */
 114   boolean (*elf_backend_symbol_table_processing) PARAMS ((bfd *,
 115                                                           elf_symbol_type *,
 116                                                           int));
 117
 118   /* A function to do additional processing on the ELF section header
 119      just before writing it out.  This is used to set the flags and
 120      type fields for some sections, or to actually write out data for
 121      unusual sections.  */
 122   boolean (*elf_backend_section_processing) PARAMS ((bfd *,
 123                                                      Elf32_Internal_Shdr *));
 124
 125   /* A function to handle unusual section types when creating BFD
 126      sections from ELF sections.  */
 127   boolean (*elf_backend_section_from_shdr) PARAMS ((bfd *,
 128                                                     Elf32_Internal_Shdr *,
 129                                                     char *));
 130
 131   /* A function to set up the ELF section header for a BFD section in
 132      preparation for writing it out.  This is where the flags and type
 133      fields are set for unusual sections.  */
 134   boolean (*elf_backend_fake_sections) PARAMS ((bfd *, Elf32_Internal_Shdr *,
 135                                                 asection *));
 136
 137   /* A function to get the ELF section index for a BFD section.  If
 138      this returns true, the section was found.  If it is a normal ELF
 139      section, *RETVAL should be left unchanged.  If it is not a normal
 140      ELF section *RETVAL should be set to the SHN_xxxx index.  */
 141   boolean (*elf_backend_section_from_bfd_section)
 142     PARAMS ((bfd *, Elf32_Internal_Shdr *, asection *, int *retval));
 143
 144   /* The swapping table to use when dealing with ECOFF information.
 145      Used for the MIPS ELF .mdebug section.  */
 146   const struct ecoff_debug_swap *elf_backend_ecoff_debug_swap;
 147 };
 148
 149 struct elf_sym_extra
 150 {
 151   int elf_sym_num;              /* sym# after locals/globals are reordered */
 152 };
 153
 154 typedef struct elf_sym_extra Elf_Sym_Extra;
 155
 156 struct bfd_elf_section_data {
 157   Elf_Internal_Shdr this_hdr;
 158   Elf_Internal_Shdr rel_hdr;
 159   int this_idx, rel_idx;
 160 };
 161 #define elf_section_data(sec)  ((struct bfd_elf_section_data*)sec->used_by_bfd)
 162 #define shdr_name(abfd,shdr)    (elf_shstrtab (abfd)->tab + (shdr)->sh_name)
 163
 164 #define get_elf_backend_data(abfd) \
 165   ((struct elf_backend_data *) (abfd)->xvec->backend_data)
 166
 167 struct strtab
 168 {
 169   char *tab;
 170   int nentries;
 171   int length;
 172 };
 173
 174 /* Some private data is stashed away for future use using the tdata pointer
 175    in the bfd structure.  */
 176
 177 struct elf_obj_tdata
 178 {
 179   Elf_Internal_Ehdr elf_header[1];      /* Actual data, but ref like ptr */
 180   Elf_Internal_Shdr **elf_sect_ptr;
 181   Elf_Internal_Phdr *phdr;
 182   struct strtab *strtab_ptr;
 183   int num_locals;
 184   int num_globals;
 185   Elf_Internal_Sym *internal_syms;
 186   elf_symbol_type *symbols;     /* elf_symbol_type */
 187   Elf_Sym_Extra *sym_extra;
 188   asymbol **section_syms;       /* STT_SECTION symbols for each section */
 189   int num_section_syms;         /* number of section_syms allocated */
 190   Elf_Internal_Shdr symtab_hdr;
 191   Elf_Internal_Shdr shstrtab_hdr;
 192   Elf_Internal_Shdr strtab_hdr;
 193   int symtab_section, shstrtab_section, strtab_section;
 194   file_ptr next_file_pos;
 195   void *prstatus;               /* The raw /proc prstatus structure */
 196   void *prpsinfo;               /* The raw /proc prpsinfo structure */
 197   bfd_vma gp;                   /* The gp value (MIPS only, for now) */
 198   int gp_size;                  /* The gp size (MIPS only, for now) */
 199 };
 200
 201 #define elf_tdata(bfd)          ((bfd) -> tdata.elf_obj_data)
 202 #define elf_elfheader(bfd)      (elf_tdata(bfd) -> elf_header)
 203 #define elf_elfsections(bfd)    (elf_tdata(bfd) -> elf_sect_ptr)
 204 #define elf_shstrtab(bfd)       (elf_tdata(bfd) -> strtab_ptr)
 205 #define elf_onesymtab(bfd)      (elf_tdata(bfd) -> symtab_section)
 206 #define elf_num_locals(bfd)     (elf_tdata(bfd) -> num_locals)
 207 #define elf_num_globals(bfd)    (elf_tdata(bfd) -> num_globals)
 208 #define elf_sym_extra(bfd)      (elf_tdata(bfd) -> sym_extra)
 209 #define elf_section_syms(bfd)   (elf_tdata(bfd) -> section_syms)
 210 #define elf_num_section_syms(bfd) (elf_tdata(bfd) -> num_section_syms)
 211 #define core_prpsinfo(bfd)      (elf_tdata(bfd) -> prpsinfo)
 212 #define core_prstatus(bfd)      (elf_tdata(bfd) -> prstatus)
 213 #define obj_symbols(bfd)        (elf_tdata(bfd) -> symbols)
 214 #define obj_internal_syms(bfd)  (elf_tdata(bfd) -> internal_syms)
 215 #define elf_gp(bfd)             (elf_tdata(bfd) -> gp)
 216 #define elf_gp_size(bfd)        (elf_tdata(bfd) -> gp_size)
 217
 218 extern char * elf_string_from_elf_section PARAMS ((bfd *, unsigned, unsigned));
 219 extern char * elf_get_str_section PARAMS ((bfd *, unsigned));
 220
 221 #define bfd_elf32_mkobject      bfd_elf_mkobject
 222 #define bfd_elf64_mkobject      bfd_elf_mkobject
 223 #define elf_mkobject            bfd_elf_mkobject
 224
 225 extern unsigned long bfd_elf_hash PARAMS ((CONST unsigned char *));
 226
 227 extern bfd_reloc_status_type bfd_elf_generic_reloc PARAMS ((bfd *,
 228                                                             arelent *,
 229                                                             asymbol *,
 230                                                             PTR,
 231                                                             asection *,
 232                                                             bfd *));
 233 extern boolean bfd_elf_mkobject PARAMS ((bfd *));
 234 extern Elf_Internal_Shdr *bfd_elf_find_section PARAMS ((bfd *, char *));
 235
 236 extern boolean bfd_elf32_write_object_contents PARAMS ((bfd *));
 237 extern boolean bfd_elf64_write_object_contents PARAMS ((bfd *));
 238
 239 extern bfd_target *bfd_elf32_object_p PARAMS ((bfd *));
 240 extern bfd_target *bfd_elf32_core_file_p PARAMS ((bfd *));
 241 extern char *bfd_elf32_core_file_failing_command PARAMS ((bfd *));
 242 extern int bfd_elf32_core_file_failing_signal PARAMS ((bfd *));
 243 extern boolean bfd_elf32_core_file_matches_executable_p PARAMS ((bfd *,
 244                                                                  bfd *));
 245 extern boolean bfd_elf32_set_section_contents PARAMS ((bfd *, sec_ptr, PTR,
 246                                                        file_ptr,
 247                                                        bfd_size_type));
 248
 249 extern unsigned int bfd_elf32_get_symtab_upper_bound PARAMS ((bfd *));
 250 extern unsigned int bfd_elf32_get_symtab PARAMS ((bfd *, asymbol **));
 251 extern unsigned int bfd_elf32_get_reloc_upper_bound PARAMS ((bfd *, sec_ptr));
 252 extern unsigned int bfd_elf32_canonicalize_reloc PARAMS ((bfd *, sec_ptr,
 253                                                           arelent **,
 254                                                           asymbol **));
 255 extern asymbol *bfd_elf32_make_empty_symbol PARAMS ((bfd *));
 256 extern void bfd_elf32_print_symbol PARAMS ((bfd *, PTR, asymbol *,
 257                                             bfd_print_symbol_type));
 258 extern void bfd_elf32_get_symbol_info PARAMS ((bfd *, asymbol *,
 259                                                symbol_info *));
 260 extern alent *bfd_elf32_get_lineno PARAMS ((bfd *, asymbol *));
 261 extern boolean bfd_elf32_set_arch_mach PARAMS ((bfd *, enum bfd_architecture,
 262                                                 unsigned long));
 263 extern boolean bfd_elf32_find_nearest_line PARAMS ((bfd *, asection *,
 264                                                     asymbol **,
 265                                                     bfd_vma, CONST char **,
 266                                                     CONST char **,
 267                                                     unsigned int *));
 268 extern int bfd_elf32_sizeof_headers PARAMS ((bfd *, boolean));
 269 extern void bfd_elf32__write_relocs PARAMS ((bfd *, asection *, PTR));
 270 extern boolean bfd_elf32_new_section_hook PARAMS ((bfd *, asection *));
 271
 272 /* If the target doesn't have reloc handling written yet:  */
 273 extern void bfd_elf32_no_info_to_howto PARAMS ((bfd *, arelent *,
 274                                                 Elf32_Internal_Rela *));
 275
 276 extern bfd_target *bfd_elf64_object_p PARAMS ((bfd *));
 277 extern bfd_target *bfd_elf64_core_file_p PARAMS ((bfd *));
 278 extern char *bfd_elf64_core_file_failing_command PARAMS ((bfd *));
 279 extern int bfd_elf64_core_file_failing_signal PARAMS ((bfd *));
 280 extern boolean bfd_elf64_core_file_matches_executable_p PARAMS ((bfd *,
 281                                                                  bfd *));
 282 extern boolean bfd_elf64_set_section_contents PARAMS ((bfd *, sec_ptr, PTR,
 283                                                        file_ptr,
 284                                                        bfd_size_type));
 285
 286 extern unsigned int bfd_elf64_get_symtab_upper_bound PARAMS ((bfd *));
 287 extern unsigned int bfd_elf64_get_symtab PARAMS ((bfd *, asymbol **));
 288 extern unsigned int bfd_elf64_get_reloc_upper_bound PARAMS ((bfd *, sec_ptr));
 289 extern unsigned int bfd_elf64_canonicalize_reloc PARAMS ((bfd *, sec_ptr,
 290                                                           arelent **,
 291                                                           asymbol **));
 292 extern asymbol *bfd_elf64_make_empty_symbol PARAMS ((bfd *));
 293 extern void bfd_elf64_print_symbol PARAMS ((bfd *, PTR, asymbol *,
 294                                             bfd_print_symbol_type));
 295 extern void bfd_elf64_get_symbol_info PARAMS ((bfd *, asymbol *,
 296                                                symbol_info *));
 297 extern alent *bfd_elf64_get_lineno PARAMS ((bfd *, asymbol *));
 298 extern boolean bfd_elf64_set_arch_mach PARAMS ((bfd *, enum bfd_architecture,
 299                                                 unsigned long));
 300 extern boolean bfd_elf64_find_nearest_line PARAMS ((bfd *, asection *,
 301                                                     asymbol **,
 302                                                     bfd_vma, CONST char **,
 303                                                     CONST char **,
 304                                                     unsigned int *));
 305 extern int bfd_elf64_sizeof_headers PARAMS ((bfd *, boolean));
 306 extern void bfd_elf64__write_relocs PARAMS ((bfd *, asection *, PTR));
 307 extern boolean bfd_elf64_new_section_hook PARAMS ((bfd *, asection *));
 308
 309 /* If the target doesn't have reloc handling written yet:  */
 310 extern void bfd_elf64_no_info_to_howto PARAMS ((bfd *, arelent *,
 311                                                 Elf64_Internal_Rela *));
 312
 313 #endif /* _LIBELF_H_ */