elf/dl-init.c

   1 /* Return the next shared object initializer function not yet run.
   2    Copyright (C) 1995, 1996, 1998 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 #include <stddef.h>
  21 #include <elf/ldsodefs.h>
  22
  23
  24 /* Run initializers for MAP and its dependencies, in inverse dependency
  25    order (that is, leaf nodes first).  */
  26
  27 ElfW(Addr)
  28 internal_function
  29 _dl_init_next (struct r_scope_elem *searchlist)
  30 {
  31   unsigned int i;
  32
  33   /* The search list for symbol lookup is a flat list in top-down
  34      dependency order, so processing that list from back to front gets us
  35      breadth-first leaf-to-root order.  */
  36
  37   i = searchlist->r_nlist;
  38   while (i-- > 0)
  39     {
  40       struct link_map *l = searchlist->r_list[i];
  41
  42       if (l->l_init_called)
  43         /* This object is all done.  */
  44         continue;
  45
  46       if (l->l_init_running)
  47         {
  48           /* This object's initializer was just running.
  49              Now mark it as having run, so this object
  50              will be skipped in the future.  */
  51           l->l_init_running = 0;
  52           l->l_init_called = 1;
  53           continue;
  54         }
  55
  56       if (l->l_info[DT_INIT]
  57           && (l->l_name[0] != '\0' || l->l_type != lt_executable))
  58         {
  59           /* Run this object's initializer.  */
  60           l->l_init_running = 1;
  61
  62           /* Print a debug message if wanted.  */
  63           if (_dl_debug_impcalls)
  64             _dl_debug_message (1, "\ncalling init: ",
  65                                 l->l_name[0] ? l->l_name : _dl_argv[0],
  66                                 "\n\n", NULL);
  67
  68           return l->l_addr + l->l_info[DT_INIT]->d_un.d_ptr;
  69         }
  70
  71       /* No initializer for this object.
  72          Mark it so we will skip it in the future.  */
  73       l->l_init_called = 1;
  74     }
  75
  76
  77   /* Notify the debugger all new objects are now ready to go.  */
  78   _r_debug.r_state = RT_CONSISTENT;
  79   _dl_debug_state ();
  80
  81   return 0;
  82 }