1/* Parse the Linux auxiliary vector.
2 Copyright (C) 1995-2023 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 <elf.h>
20#include <entry.h>
21#include <fpu_control.h>
22#include <ldsodefs.h>
23#include <link.h>
24
25typedef ElfW(Addr) dl_parse_auxv_t[AT_MINSIGSTKSZ + 1];
26
27/* Copy the auxiliary vector into AUXV_VALUES and set up GLRO
28 variables. */
29static inline
30void _dl_parse_auxv (ElfW(auxv_t) *av, dl_parse_auxv_t auxv_values)
31{
32 auxv_values[AT_ENTRY] = (ElfW(Addr)) ENTRY_POINT;
33 auxv_values[AT_PAGESZ] = EXEC_PAGESIZE;
34 auxv_values[AT_FPUCW] = _FPU_DEFAULT;
35
36 /* NB: Default to a constant CONSTANT_MINSIGSTKSZ. */
37 _Static_assert (__builtin_constant_p (CONSTANT_MINSIGSTKSZ),
38 "CONSTANT_MINSIGSTKSZ is constant");
39 auxv_values[AT_MINSIGSTKSZ] = CONSTANT_MINSIGSTKSZ;
40
41 for (; av->a_type != AT_NULL; av++)
42 if (av->a_type <= AT_MINSIGSTKSZ)
43 auxv_values[av->a_type] = av->a_un.a_val;
44
45 GLRO(dl_pagesize) = auxv_values[AT_PAGESZ];
46 __libc_enable_secure = auxv_values[AT_SECURE];
47 GLRO(dl_platform) = (void *) auxv_values[AT_PLATFORM];
48 GLRO(dl_hwcap) = auxv_values[AT_HWCAP];
49 GLRO(dl_hwcap2) = auxv_values[AT_HWCAP2];
50 GLRO(dl_clktck) = auxv_values[AT_CLKTCK];
51 GLRO(dl_fpu_control) = auxv_values[AT_FPUCW];
52 _dl_random = (void *) auxv_values[AT_RANDOM];
53 GLRO(dl_minsigstacksize) = auxv_values[AT_MINSIGSTKSZ];
54 GLRO(dl_sysinfo_dso) = (void *) auxv_values[AT_SYSINFO_EHDR];
55#ifdef NEED_DL_SYSINFO
56 if (GLRO(dl_sysinfo_dso) != NULL)
57 GLRO(dl_sysinfo) = auxv_values[AT_SYSINFO];
58#endif
59
60 DL_PLATFORM_AUXV
61}
62