sysdeps/i386/init-first.c

   1 /* Initialization code run first thing by the ELF startup code.  For i386/Unix.
   2   Copyright (C) 1995, 1996, 1997 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 <unistd.h>
  21
  22 extern void __libc_init (int, char **, char **);
  23 extern void __getopt_clean_environment (void);
  24 extern void __libc_global_ctors (void);
  25
  26 int __libc_multiple_libcs = 1;
  27
  28 static void
  29 init (int *data)
  30 {
  31   int argc = *data;
  32   char **argv = (void *) (data + 1);
  33   char **envp = &argv[argc + 1];
  34
  35   __environ = envp;
  36   __libc_init (argc, argv, envp);
  37
  38   /* This is a hack to make the special getopt in GNU libc working.  */
  39   __getopt_clean_environment ();
  40 }
  41
  42 #ifdef PIC
  43 /* This function is called to initialize the shared C library.
  44    It is called just before the user _start code from i386/elf/start.S,
  45    with the stack set up as that code gets it.  */
  46
  47 /* NOTE!  The linker notices the magical name `_init' and sets the DT_INIT
  48    pointer in the dynamic section based solely on that.  It is convention
  49    for this function to be in the `.init' section, but the symbol name is
  50    the only thing that really matters!!  */
  51 /*void _init (int argc, ...) __attribute__ ((unused, section (".init")));*/
  52
  53 void
  54 _init (int argc, ...)
  55 {
  56   init (&argc);
  57
  58   __libc_global_ctors ();
  59 }
  60 #endif
  61
  62
  63 void
  64 __libc_init_first (int argc __attribute__ ((unused)), ...)
  65 {
  66 #ifndef PIC
  67   init (&argc);
  68 #endif
  69 }