csu/init-first.c

   1 /* Initialization code run first thing by the ELF startup code.  Stub version.
   2    Copyright (C) 1995-2012 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 Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the 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    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <ctype.h>
  20 #include <unistd.h>
  21 #include <sys/types.h>
  22
  23 /* Set nonzero if we have to be prepared for more then one libc being
  24    used in the process.  Safe assumption if initializer never runs.  */
  25 int __libc_multiple_libcs attribute_hidden = 1;
  26
  27 extern void __libc_init (int, char **, char **);
  28 #ifdef USE_NONOPTION_FLAGS
  29 extern void __getopt_clean_environment (char **);
  30 #endif
  31
  32 #ifdef SHARED
  33 void
  34 __libc_init_first (void)
  35 {
  36 }
  37 #endif
  38
  39 #ifdef SHARED
  40 /* NOTE!  The linker notices the magical name `_init' and sets the DT_INIT
  41    pointer in the dynamic section based solely on that.  It is convention
  42    for this function to be in the `.init' section, but the symbol name is
  43    the only thing that really matters!!  */
  44 void _init
  45 #else
  46 void __libc_init_first
  47 #endif
  48 (int argc, char *arg0, ...)
  49 {
  50   char **argv = &arg0, **envp = &argv[argc + 1];
  51
  52   __environ = envp;
  53   __libc_init (argc, argv, envp);
  54
  55 #ifdef USE_NONOPTION_FLAGS
  56   /* This is a hack to make the special getopt in GNU libc working.  */
  57   __getopt_clean_environment (envp);
  58 #endif
  59
  60   /* Initialize ctype data.  */
  61   __ctype_init ();
  62 }