glibc/elf/dl-init.c

/* Return the next shared object initializer function not yet run.
Copyright (C) 1995, 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <stddef.h>
#include <link.h>


/* Run initializers for MAP and its dependencies, in inverse dependency
   order (that is, leaf nodes first).  */

Elf32_Addr
_dl_init_next (struct link_map *map)
{
  unsigned int i;

  /* The search list for symbol lookup is a flat list in top-down
     dependency order, so processing that list from back to front gets us
     breadth-first leaf-to-root order.  */

  i = map->l_nsearchlist;
  while (i-- > 0)
    {
      struct link_map *l = map->l_searchlist[i];

      if (l->l_init_called)
	/* This object is all done.  */
	continue;

      if (l->l_init_running)
	{
	  /* This object's initializer was just running.
	     Now mark it as having run, so this object
	     will be skipped in the future.  */
	  l->l_init_running = 0;
	  l->l_init_called = 1;
	  continue;
	}

      if (l->l_info[DT_INIT] &&
	  !(l->l_name[0] == '\0' && l->l_type == lt_executable))
	{
	  /* Run this object's initializer.  */
	  l->l_init_running = 1;
	  return l->l_addr + l->l_info[DT_INIT]->d_un.d_ptr;
	}

      /* No initializer for this object.
	 Mark it so we will skip it in the future.  */
      l->l_init_called = 1;
    }

  return 0;
}