Blame csu/elf-init.c

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/* Startup support for ELF initializers/finalizers in the main executable.
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   Copyright (C) 2002-2018 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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   The GNU C Library is free software; you can redistribute it and/or
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   modify it under the terms of the GNU Lesser General Public
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   License as published by the Free Software Foundation; either
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   version 2.1 of the License, or (at your option) any later version.
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   In addition to the permissions in the GNU Lesser General Public
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   License, the Free Software Foundation gives you unlimited
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   permission to link the compiled version of this file with other
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   programs, and to distribute those programs without any restriction
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   coming from the use of this file. (The GNU Lesser General Public
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   License restrictions do apply in other respects; for example, they
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   cover modification of the file, and distribution when not linked
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   into another program.)
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   Note that people who make modified versions of this file are not
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   obligated to grant this special exception for their modified
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   versions; it is their choice whether to do so. The GNU Lesser
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   General Public License gives permission to release a modified
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   version without this exception; this exception also makes it
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   possible to release a modified version which carries forward this
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   exception.
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   The GNU C Library is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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   Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public
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   License along with the GNU C Library; if not, see
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   <http://www.gnu.org/licenses/>.  */
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#include <stddef.h>
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/* These magic symbols are provided by the linker.  */
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extern void (*__preinit_array_start []) (int, char **, char **)
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  attribute_hidden;
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extern void (*__preinit_array_end []) (int, char **, char **)
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  attribute_hidden;
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extern void (*__init_array_start []) (int, char **, char **)
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  attribute_hidden;
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extern void (*__init_array_end []) (int, char **, char **)
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  attribute_hidden;
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extern void (*__fini_array_start []) (void) attribute_hidden;
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extern void (*__fini_array_end []) (void) attribute_hidden;
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#ifndef NO_INITFINI
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/* These function symbols are provided for the .init/.fini section entry
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   points automagically by the linker.  */
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extern void _init (void);
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extern void _fini (void);
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#endif
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/* These functions are passed to __libc_start_main by the startup code.
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   These get statically linked into each program.  For dynamically linked
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   programs, this module will come from libc_nonshared.a and differs from
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   the libc.a module in that it doesn't call the preinit array.  */
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void
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__libc_csu_init (int argc, char **argv, char **envp)
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{
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  /* For dynamically linked executables the preinit array is executed by
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     the dynamic linker (before initializing any shared object).  */
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#ifndef LIBC_NONSHARED
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  /* For static executables, preinit happens right before init.  */
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  {
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    const size_t size = __preinit_array_end - __preinit_array_start;
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    size_t i;
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    for (i = 0; i < size; i++)
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      (*__preinit_array_start [i]) (argc, argv, envp);
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  }
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#endif
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#ifndef NO_INITFINI
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  _init ();
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#endif
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  const size_t size = __init_array_end - __init_array_start;
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  for (size_t i = 0; i < size; i++)
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      (*__init_array_start [i]) (argc, argv, envp);
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}
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/* This function should not be used anymore.  We run the executable's
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   destructor now just like any other.  We cannot remove the function,
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   though.  */
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void
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__libc_csu_fini (void)
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{
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#ifndef LIBC_NONSHARED
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  size_t i = __fini_array_end - __fini_array_start;
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  while (i-- > 0)
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    (*__fini_array_start [i]) ();
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# ifndef NO_INITFINI
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  _fini ();
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# endif
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#endif
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}