libgcc/config/rs6000/on_exit.c

/* Copyright (C) 1999-2021 Free Software Foundation, Inc.

   NOTE: This source is derived from an old version taken from the GNU C
   Library (glibc).

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 3, or (at your option) any later
version.

GCC 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 General Public License
for more details.

Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.

You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
<http://www.gnu.org/licenses/>.  */

#include <stdlib.h>
#include "exit.h"

#define atomic_write_barrier() __asm__ ("eieio" ::: "memory")

/* Register a function to be called by exit.  */
int
on_exit (void (*func) (int status, void *arg), void *arg)
{
  struct exit_function *new = __new_exitfn (&__exit_funcs);

  if (new == NULL)
    return -1;

#ifdef PTR_MANGLE
  PTR_MANGLE (func);
#endif
  new->func.on.fn = func;
  new->func.on.arg = arg;
  atomic_write_barrier ();
  new->flavor = ef_on;
  return 0;
}