| 1 | /* Parse the Linux auxiliary vector. |
|---|---|
| 2 | Copyright (C) 1995-2022 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 <elf.h> |
| 20 | #include <entry.h> |
| 21 | #include <fpu_control.h> |
| 22 | #include <ldsodefs.h> |
| 23 | #include <link.h> |
| 24 | |
| 25 | typedef ElfW(Addr) dl_parse_auxv_t[AT_MINSIGSTKSZ + 1]; |
| 26 | |
| 27 | /* Copy the auxiliary vector into AUXV_VALUES and set up GLRO |
| 28 | variables. */ |
| 29 | static inline |
| 30 | void _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 |