1  /* Invoke the early initialization function in libc.so.
       2     Copyright (C) 2020-2023 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
      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  }