1/* Check if internal buffer reallocation work for large paths (BZ #28126)
2 Copyright (C) 2021-2022 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 <errno.h>
20#include <ftw.h>
21#include <limits.h>
22#include <string.h>
23#include <stdlib.h>
24#include <support/check.h>
25#include <support/support.h>
26#include <support/temp_file.h>
27#include <support/xunistd.h>
28#include <stdio.h>
29
30static int
31my_func (const char *file, const struct stat *sb, int flag)
32{
33 return 0;
34}
35
36static const char folder[NAME_MAX] = { [0 ... 253] = 'a', [254] = '\0' };
37
38#define NSUBFOLDERS 16
39static int nsubfolders;
40
41static void
42do_cleanup (void)
43{
44 xchdir (path: "..");
45 for (int i = 0; i < nsubfolders; i++)
46 {
47 remove (folder);
48 xchdir (path: "..");
49 }
50 remove (folder);
51}
52#define CLEANUP_HANDLER do_cleanup
53
54static void
55check_mkdir (const char *path)
56{
57 int r = mkdir (path: path, mode: 0777);
58 /* Some filesystem such as overlayfs does not support larger path required
59 to trigger the internal buffer reallocation. */
60 if (r != 0)
61 {
62 if (errno == ENAMETOOLONG)
63 FAIL_UNSUPPORTED ("the filesystem does not support the required"
64 "large path");
65 else
66 FAIL_EXIT1 ("mkdir (\"%s\", 0%o): %m", folder, 0777);
67 }
68}
69
70static int
71do_test (void)
72{
73 char *tempdir = support_create_temp_directory (base: "tst-bz28126");
74
75 /* Create path with various subfolders to force an internal buffer
76 reallocation within ntfw. */
77 char *path = xasprintf (format: "%s/%s", tempdir, folder);
78 check_mkdir (path);
79 xchdir (path);
80 free (ptr: path);
81 for (int i = 0; i < NSUBFOLDERS - 1; i++)
82 {
83 check_mkdir (path: folder);
84 xchdir (path: folder);
85 nsubfolders++;
86 }
87
88 TEST_COMPARE (ftw (tempdir, my_func, 20), 0);
89
90 free (ptr: tempdir);
91
92 do_cleanup ();
93
94 return 0;
95}
96
97#include <support/test-driver.c>
98

source code of glibc/io/tst-ftw-bz28126.c