ports/sysdeps/unix/sysv/linux/mips/dl-static.c

   1 /* Variable initialization.  MIPS version.
   2    Copyright (C) 2001, 2002, 2003, 2005 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 Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <ldsodefs.h>
  20
  21 #ifdef SHARED
  22
  23 void
  24 _dl_var_init (void *array[])
  25 {
  26   /* It has to match "variables" below. */
  27   enum
  28     {
  29       DL_PAGESIZE = 0
  30     };
  31
  32   GLRO(dl_pagesize) = *((size_t *) array[DL_PAGESIZE]);
  33 }
  34
  35 #else
  36 #include <bits/libc-lock.h>
  37
  38 __libc_lock_define_initialized_recursive (static, _dl_static_lock)
  39
  40 static void *variables[] =
  41 {
  42   &GLRO(dl_pagesize)
  43 };
  44
  45 static void
  46 _dl_unprotect_relro (struct link_map *l)
  47 {
  48   ElfW(Addr) start = ((l->l_addr + l->l_relro_addr)
  49                       & ~(GLRO(dl_pagesize) - 1));
  50   ElfW(Addr) end = ((l->l_addr + l->l_relro_addr + l->l_relro_size)
  51                     & ~(GLRO(dl_pagesize) - 1));
  52
  53   if (start != end)
  54     __mprotect ((void *) start, end - start, PROT_READ | PROT_WRITE);
  55 }
  56
  57 void
  58 _dl_static_init (struct link_map *l)
  59 {
  60   struct link_map *rtld_map = l;
  61   struct r_scope_elem **scope;
  62   const ElfW(Sym) *ref = NULL;
  63   lookup_t loadbase;
  64   void (*f) (void *[]);
  65   size_t i;
  66
  67   __libc_lock_lock_recursive (_dl_static_lock);
  68
  69   loadbase = _dl_lookup_symbol_x ("_dl_var_init", l, &ref, l->l_local_scope,
  70                                   NULL, 0, 1, NULL);
  71
  72   for (scope = l->l_local_scope; *scope != NULL; scope++)
  73     for (i = 0; i < (*scope)->r_nlist; i++)
  74       if ((*scope)->r_list[i] == loadbase)
  75         {
  76           rtld_map = (*scope)->r_list[i];
  77           break;
  78         }
  79
  80   if (ref != NULL)
  81     {
  82       f = (void (*) (void *[])) DL_SYMBOL_ADDRESS (loadbase, ref);
  83       _dl_unprotect_relro (rtld_map);
  84       f (variables);
  85       _dl_protect_relro (rtld_map);
  86     }
  87
  88   __libc_lock_unlock_recursive (_dl_static_lock);
  89 }
  90
  91 #endif