glibc/sysdeps/i386/init-first.c

/* Initialization code run first thing by the ELF startup code.  For i386/Unix.
  Copyright (C) 1995, 1996, 1997 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., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <unistd.h>

extern void __libc_init (int, char **, char **);
extern void __getopt_clean_environment (void);
extern void __libc_global_ctors (void);

int __libc_multiple_libcs = 1;

static void
init (int *data)
{
  int argc = *data;
  char **argv = (void *) (data + 1);
  char **envp = &argv[argc + 1];

  __environ = envp;
  __libc_init (argc, argv, envp);

  /* This is a hack to make the special getopt in GNU libc working.  */
  __getopt_clean_environment ();
}

#ifdef PIC
/* This function is called to initialize the shared C library.
   It is called just before the user _start code from i386/elf/start.S,
   with the stack set up as that code gets it.  */

/* NOTE!  The linker notices the magical name `_init' and sets the DT_INIT
   pointer in the dynamic section based solely on that.  It is convention
   for this function to be in the `.init' section, but the symbol name is
   the only thing that really matters!!  */
/*void _init (int argc, ...) __attribute__ ((unused, section (".init")));*/

void
_init (int argc, ...)
{
  init (&argc);

  __libc_global_ctors ();
}
#endif


void
__libc_init_first (int argc __attribute__ ((unused)), ...)
{
#ifndef PIC
  init (&argc);
#endif
}