| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame] | 1 | /* Environment handling for dynamic loader. |
| 2 | Copyright (C) 1995-2016 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 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #include <string.h> |
| 20 | #include <stdlib.h> |
| 21 | #include <unistd.h> |
| 22 | #include <ldsodefs.h> |
| 23 | |
| 24 | /* Walk through the environment of the process and return all entries |
| 25 | starting with `LD_'. */ |
| 26 | char * |
| 27 | internal_function |
| 28 | _dl_next_ld_env_entry (char ***position) |
| 29 | { |
| 30 | char **current = *position; |
| 31 | char *result = NULL; |
| 32 | |
| 33 | while (*current != NULL) |
| 34 | { |
| 35 | if (__builtin_expect ((*current)[0] == 'L', 0) |
| 36 | && (*current)[1] == 'D' && (*current)[2] == '_') |
| 37 | { |
| 38 | result = &(*current)[3]; |
| 39 | |
| 40 | /* Save current position for next visit. */ |
| 41 | *position = ++current; |
| 42 | |
| 43 | break; |
| 44 | } |
| 45 | |
| 46 | ++current; |
| 47 | } |
| 48 | |
| 49 | return result; |
| 50 | } |
| 51 | |
| 52 | |
| 53 | /* In ld.so __environ is not exported. */ |
| 54 | extern char **__environ attribute_hidden; |
| 55 | |
| 56 | int |
| 57 | unsetenv (const char *name) |
| 58 | { |
| 59 | char **ep; |
| 60 | |
| 61 | ep = __environ; |
| 62 | while (*ep != NULL) |
| 63 | { |
| 64 | size_t cnt = 0; |
| 65 | |
| 66 | while ((*ep)[cnt] == name[cnt] && name[cnt] != '\0') |
| 67 | ++cnt; |
| 68 | |
| 69 | if (name[cnt] == '\0' && (*ep)[cnt] == '=') |
| 70 | { |
| 71 | /* Found it. Remove this pointer by moving later ones to |
| 72 | the front. */ |
| 73 | char **dp = ep; |
| 74 | |
| 75 | do |
| 76 | dp[0] = dp[1]; |
| 77 | while (*dp++); |
| 78 | /* Continue the loop in case NAME appears again. */ |
| 79 | } |
| 80 | else |
| 81 | ++ep; |
| 82 | } |
| 83 | |
| 84 | return 0; |
| 85 | } |