1 /* Error-checking, allocating wrapper for readlink. 2 Copyright (C) 2017-2022 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 <scratch_buffer.h> 20 #include <support/check.h> 21 #include <support/support.h> 22 #include <xunistd.h> 23 24 char * xreadlink(const char * path)25xreadlink (const char *path) 26 { 27 struct scratch_buffer buf; 28 scratch_buffer_init (&buf); 29 30 while (true) 31 { 32 ssize_t count = readlink (path, buf.data, buf.length); 33 if (count < 0) 34 FAIL_EXIT1 ("readlink (\"%s\"): %m", path); 35 if (count < buf.length) 36 { 37 char *result = xstrndup (buf.data, count); 38 scratch_buffer_free (&buf); 39 return result; 40 } 41 if (!scratch_buffer_grow (&buf)) 42 FAIL_EXIT1 ("scratch_buffer_grow in xreadlink"); 43 } 44 } 45