sysdeps/generic/dl-prop.h

   1 /* Support for GNU properties.  Generic version.
   2    Copyright (C) 2018-2023 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 #ifndef _DL_PROP_H
  20 #define _DL_PROP_H
  21
  22 /* The following functions are used by the dynamic loader and the
  23    dlopen machinery to process PT_NOTE and PT_GNU_PROPERTY entries in
  24    the binary or shared object.  The notes can be used to change the
  25    behaviour of the loader, and as such offer a flexible mechanism
  26    for hooking in various checks related to ABI tags or implementing
  27    "flag day" ABI transitions.  */
  28
  29 static inline void __attribute__ ((always_inline))
  30 _rtld_main_check (struct link_map *m, const char *program)
  31 {
  32 }
  33
  34 static inline void __attribute__ ((always_inline))
  35 _dl_open_check (struct link_map *m)
  36 {
  37 }
  38
  39 static inline void __attribute__ ((always_inline))
  40 _dl_process_pt_note (struct link_map *l, int fd, const ElfW(Phdr) *ph)
  41 {
  42 }
  43
  44 /* Called for each property in the NT_GNU_PROPERTY_TYPE_0 note of L,
  45    processing of the properties continues until this returns 0.  */
  46 static inline int __attribute__ ((always_inline))
  47 _dl_process_gnu_property (struct link_map *l, int fd, uint32_t type,
  48                           uint32_t datasz, void *data)
  49 {
  50   /* Continue until GNU_PROPERTY_1_NEEDED is found.  */
  51   if (type == GNU_PROPERTY_1_NEEDED)
  52     {
  53       if (datasz == 4)
  54         l->l_1_needed = *(unsigned int *) data;
  55       return 0;
  56     }
  57   return 1;
  58 }
  59
  60 #endif /* _DL_PROP_H */