1 /* Invoke the early initialization function in libc.so.
2    Copyright (C) 2020-2022 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    <https://www.gnu.org/licenses/>.  */
18 
19 #include <assert.h>
20 #include <ldsodefs.h>
21 #include <libc-early-init.h>
22 #include <link.h>
23 #include <stddef.h>
24 
25 void
_dl_call_libc_early_init(struct link_map * libc_map,_Bool initial)26 _dl_call_libc_early_init (struct link_map *libc_map, _Bool initial)
27 {
28   /* There is nothing to do if we did not actually load libc.so.  */
29   if (libc_map == NULL)
30     return;
31 
32   const ElfW(Sym) *sym
33     = _dl_lookup_direct (libc_map, "__libc_early_init",
34                          0x069682ac, /* dl_new_hash output.  */
35                          "GLIBC_PRIVATE",
36                          0x0963cf85); /* _dl_elf_hash output.  */
37   assert (sym != NULL);
38   __typeof (__libc_early_init) *early_init
39     = DL_SYMBOL_ADDRESS (libc_map, sym);
40   early_init (initial);
41 }
42