| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame^] | 1 | /* Handling of dynamic sring tokens. |
| 2 | Copyright (C) 1999-2016 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 "trusted-dirs.h" |
| 20 | |
| 21 | /* Determine the number of DST elements in the name. Only if IS_PATH is |
| 22 | nonzero paths are recognized (i.e., multiple, ':' separated filenames). */ |
| 23 | #define DL_DST_COUNT(name, is_path) \ |
| 24 | ({ \ |
| 25 | size_t __cnt = 0; \ |
| 26 | const char *__sf = strchr (name, '$'); \ |
| 27 | \ |
| 28 | if (__glibc_unlikely (__sf != NULL)) \ |
| 29 | __cnt = _dl_dst_count (__sf, is_path); \ |
| 30 | \ |
| 31 | __cnt; }) |
| 32 | |
| 33 | |
| 34 | #ifdef SHARED |
| 35 | # define IS_RTLD(l) (l) == &GL(dl_rtld_map) |
| 36 | #else |
| 37 | # define IS_RTLD(l) 0 |
| 38 | #endif |
| 39 | /* Guess from the number of DSTs the length of the result string. */ |
| 40 | #define DL_DST_REQUIRED(l, name, len, cnt) \ |
| 41 | ({ \ |
| 42 | size_t __len = (len); \ |
| 43 | size_t __cnt = (cnt); \ |
| 44 | \ |
| 45 | if (__cnt > 0) \ |
| 46 | { \ |
| 47 | size_t dst_len; \ |
| 48 | /* Now we make a guess how many extra characters on top of the \ |
| 49 | length of S we need to represent the result. We know that \ |
| 50 | we have CNT replacements. Each at most can use \ |
| 51 | MAX (MAX (strlen (ORIGIN), strlen (_dl_platform)), \ |
| 52 | strlen (DL_DST_LIB)) \ |
| 53 | minus 4 (which is the length of "$LIB"). \ |
| 54 | \ |
| 55 | First get the origin string if it is not available yet. \ |
| 56 | This can only happen for the map of the executable or, when \ |
| 57 | auditing, in ld.so. */ \ |
| 58 | if ((l)->l_origin == NULL) \ |
| 59 | { \ |
| 60 | assert ((l)->l_name[0] == '\0' || IS_RTLD (l)); \ |
| 61 | (l)->l_origin = _dl_get_origin (); \ |
| 62 | dst_len = ((l)->l_origin && (l)->l_origin != (char *) -1 \ |
| 63 | ? strlen ((l)->l_origin) : 0); \ |
| 64 | } \ |
| 65 | else \ |
| 66 | dst_len = (l)->l_origin == (char *) -1 \ |
| 67 | ? 0 : strlen ((l)->l_origin); \ |
| 68 | dst_len = MAX (MAX (dst_len, GLRO(dl_platformlen)), \ |
| 69 | strlen (DL_DST_LIB)); \ |
| 70 | if (dst_len > 4) \ |
| 71 | __len += __cnt * (dst_len - 4); \ |
| 72 | } \ |
| 73 | \ |
| 74 | __len; }) |