1 /* Copyright (C) 1991-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <assert.h>
19 #include <stdlib.h>
20 #include "exit.h"
21 #include <sysdep.h>
22 
23 /* Register a function to be called by exit.  */
24 int
__on_exit(void (* func)(int status,void * arg),void * arg)25 __on_exit (void (*func) (int status, void *arg), void *arg)
26 {
27   struct exit_function *new;
28 
29   /* As a QoI issue we detect NULL early with an assertion instead
30      of a SIGSEGV at program exit when the handler is run (bug 20544).  */
31   assert (func != NULL);
32 
33    __libc_lock_lock (__exit_funcs_lock);
34   new = __new_exitfn (&__exit_funcs);
35 
36   if (new == NULL)
37     {
38       __libc_lock_unlock (__exit_funcs_lock);
39       return -1;
40     }
41 
42 #ifdef PTR_MANGLE
43   PTR_MANGLE (func);
44 #endif
45   new->func.on.fn = func;
46   new->func.on.arg = arg;
47   new->flavor = ef_on;
48   __libc_lock_unlock (__exit_funcs_lock);
49   return 0;
50 }
51 weak_alias (__on_exit, on_exit)
52