diff options
Diffstat (limited to 'elf/dl-static-tls.h')
| -rw-r--r-- | elf/dl-static-tls.h | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/elf/dl-static-tls.h b/elf/dl-static-tls.h new file mode 100644 index 0000000000..730924fc01 --- /dev/null +++ b/elf/dl-static-tls.h @@ -0,0 +1,51 @@ +/* Inline functions for dynamic linking. + Copyright (C) 1995-2021 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +#ifndef _DL_STATIC_TLS_H +#define _DL_STATIC_TLS_H + +/* This macro is used as a callback from elf_machine_rel{a,} when a + static TLS reloc is about to be performed. Since (in dl-load.c) we + permit dynamic loading of objects that might use such relocs, we + have to check whether each use is actually doable. If the object + whose TLS segment the reference resolves to was allocated space in + the static TLS block at startup, then it's ok. Otherwise, we make + an attempt to allocate it in surplus space on the fly. If that + can't be done, we fall back to the error that DF_STATIC_TLS is + intended to produce. */ +#define HAVE_STATIC_TLS(map, sym_map) \ + (__builtin_expect ((sym_map)->l_tls_offset != NO_TLS_OFFSET \ + && ((sym_map)->l_tls_offset \ + != FORCED_DYNAMIC_TLS_OFFSET), 1)) + +#define CHECK_STATIC_TLS(map, sym_map) \ + do { \ + if (!HAVE_STATIC_TLS (map, sym_map)) \ + _dl_allocate_static_tls (sym_map); \ + } while (0) + +#define TRY_STATIC_TLS(map, sym_map) \ + (__builtin_expect ((sym_map)->l_tls_offset \ + != FORCED_DYNAMIC_TLS_OFFSET, 1) \ + && (__builtin_expect ((sym_map)->l_tls_offset != NO_TLS_OFFSET, 1) \ + || _dl_try_allocate_static_tls (sym_map, true) == 0)) + +int _dl_try_allocate_static_tls (struct link_map *map, bool optional) + attribute_hidden; + +#endif |