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 <link.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 _dl_init_next (struct link_map *map)
  29 {
  30   unsigned int i;
  31
  32   /* The search list for symbol lookup is a flat list in top-down
  33      dependency order, so processing that list from back to front gets us
  34      breadth-first leaf-to-root order.  */
  35
  36   i = map->l_nsearchlist;
  37   while (i-- > 0)
  38     {
  39       struct link_map *l = map->l_searchlist[i];
  40
  41       if (l->l_init_called)
  42         /* This object is all done.  */
  43         continue;
  44
  45       if (l->l_init_running)
  46         {
  47           /* This object's initializer was just running.
  48              Now mark it as having run, so this object
  49              will be skipped in the future.  */
  50           l->l_init_running = 0;
  51           l->l_init_called = 1;
  52           continue;
  53         }
  54
  55       if (l->l_info[DT_INIT] &&
  56           !(l->l_name[0] == '\0' && l->l_type == lt_executable))
  57         {
  58           /* Run this object's initializer.  */
  59           l->l_init_running = 1;
  60
  61           /* Print a debug message if wanted.  */
  62           if (_dl_debug_impcalls)
  63             _dl_debug_message (1, "\ncalling init: ",
  64                                 l->l_name[0] ? l->l_name : _dl_argv[0],
  65                                 "\n\n", NULL);
  66
  67           return l->l_addr + l->l_info[DT_INIT]->d_un.d_ptr;
  68         }
  69
  70       /* No initializer for this object.
  71          Mark it so we will skip it in the future.  */
  72       l->l_init_called = 1;
  73     }
  74
  75
  76   /* Notify the debugger all new objects are now ready to go.  */
  77   _r_debug.r_state = RT_CONSISTENT;
  78   _dl_debug_state ();
  79
  80   return 0;
  81 }