elf/do-rel.h

   1 /* Do relocations for ELF dynamic linking.
   2    Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 /* This file may be included twice, to define both
  21    `elf_dynamic_do_rel' and `elf_dynamic_do_rela'.  */
  22
  23 #ifdef DO_RELA
  24 # define elf_dynamic_do_rel     elf_dynamic_do_rela
  25 # define Rel                    Rela
  26 # define elf_machine_rel        elf_machine_rela
  27 #endif
  28
  29 #ifndef VERSYMIDX
  30 # define VERSYMIDX(sym) (DT_NUM + DT_PROCNUM + DT_VERSIONTAGIDX (sym))
  31 #endif
  32
  33 /* Perform the relocations in MAP on the running program image as specified
  34    by RELTAG, SZTAG.  If LAZY is nonzero, this is the first pass on PLT
  35    relocations; they should be set up to call _dl_runtime_resolve, rather
  36    than fully resolved now.  */
  37
  38 static inline void
  39 elf_dynamic_do_rel (struct link_map *map,
  40                     ElfW(Addr) reladdr, ElfW(Addr) relsize,
  41                     int lazy)
  42 {
  43   const ElfW(Rel) *r = (const ElfW(Rel) *)(map->l_addr + reladdr);
  44   const ElfW(Rel) *end = (const ElfW(Rel) *)(map->l_addr + reladdr + relsize);
  45
  46   if (lazy)
  47     /* Doing lazy PLT relocations; they need very little info.  */
  48     for (; r < end; ++r)
  49       elf_machine_lazy_rel (map, r);
  50   else
  51     {
  52       const ElfW(Sym) *const symtab =
  53         (const ElfW(Sym) *) (map->l_addr + map->l_info[DT_SYMTAB]->d_un.d_ptr);
  54
  55       if (map->l_info[VERSYMIDX (DT_VERSYM)])
  56         {
  57           const ElfW(Half) *const version =
  58             (const ElfW(Half) *) (map->l_addr
  59                                   + map->l_info[VERSYMIDX (DT_VERSYM)]->d_un.d_ptr);
  60
  61           for (; r < end; ++r)
  62             {
  63               ElfW(Half) ndx = version[ELFW(R_SYM) (r->r_info)];
  64               elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)],
  65                                &map->l_versions[ndx],
  66                                (void *) (map->l_addr + r->r_offset));
  67             }
  68         }
  69       else
  70         for (; r < end; ++r)
  71           elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)], NULL,
  72                            (void *) (map->l_addr + r->r_offset));
  73     }
  74 }
  75
  76 #undef elf_dynamic_do_rel
  77 #undef Rel
  78 #undef elf_machine_rel