1 /* Handling of dynamic sring tokens. 2 Copyright (C) 1999-2022 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 "trusted-dirs.h" 20 21 #ifdef SHARED 22 # define IS_RTLD(l) (l) == &GL(dl_rtld_map) 23 #else 24 # define IS_RTLD(l) 0 25 #endif 26 /* Guess from the number of DSTs the length of the result string. */ 27 #define DL_DST_REQUIRED(l, name, len, cnt) \ 28 ({ \ 29 size_t __len = (len); \ 30 size_t __cnt = (cnt); \ 31 \ 32 if (__cnt > 0) \ 33 { \ 34 size_t dst_len; \ 35 /* Now we make a guess how many extra characters on top of the \ 36 length of S we need to represent the result. We know that \ 37 we have CNT replacements. Each at most can use \ 38 MAX (MAX (strlen (ORIGIN), strlen (_dl_platform)), \ 39 strlen (DL_DST_LIB)) \ 40 minus 4 (which is the length of "$LIB"). \ 41 \ 42 First get the origin string if it is not available yet. \ 43 This can only happen for the map of the executable or, when \ 44 auditing, in ld.so. */ \ 45 if ((l)->l_origin == NULL) \ 46 { \ 47 assert ((l)->l_name[0] == '\0' || IS_RTLD (l)); \ 48 (l)->l_origin = _dl_get_origin (); \ 49 dst_len = ((l)->l_origin && (l)->l_origin != (char *) -1 \ 50 ? strlen ((l)->l_origin) : 0); \ 51 } \ 52 else \ 53 dst_len = (l)->l_origin == (char *) -1 \ 54 ? 0 : strlen ((l)->l_origin); \ 55 dst_len = MAX (MAX (dst_len, GLRO(dl_platformlen)), \ 56 strlen (DL_DST_LIB)); \ 57 if (dst_len > 4) \ 58 __len += __cnt * (dst_len - 4); \ 59 } \ 60 \ 61 __len; }) 62