1/* Error-checking, allocating wrapper for readlink.
2 Copyright (C) 2017-2023 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
24char *
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