io/tst-ftw-bz28126.c

   1 /* Check if internal buffer reallocation work for large paths (BZ #28126)
   2    Copyright (C) 2021-2024 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
  30 static int
  31 my_func (const char *file, const struct stat *sb, int flag)
  32 {
  33   return 0;
  34 }
  35
  36 static const char folder[NAME_MAX] = { [0 ... 253] = 'a', [254] = '\0' };
  37
  38 #define NSUBFOLDERS 16
  39 static int nsubfolders;
  40
  41 static void
  42 do_cleanup (void)
  43 {
  44   xchdir ("..");
  45   for (int i = 0; i < nsubfolders; i++)
  46     {
  47       remove (folder);
  48       xchdir ("..");
  49     }
  50   remove (folder);
  51 }
  52 #define CLEANUP_HANDLER do_cleanup
  53
  54 static void
  55 check_mkdir (const char *path)
  56 {
  57   int r = mkdir (path, 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
  70 static int
  71 do_test (void)
  72 {
  73   char *tempdir = support_create_temp_directory ("tst-bz28126");
  74
  75   /* Create path with various subfolders to force an internal buffer
  76      reallocation within ntfw.  */
  77   char *path = xasprintf ("%s/%s", tempdir, folder);
  78   check_mkdir (path);
  79   xchdir (path);
  80   free (path);
  81   for (int i = 0; i < NSUBFOLDERS - 1; i++)
  82     {
  83       check_mkdir (folder);
  84       xchdir (folder);
  85       nsubfolders++;
  86     }
  87
  88   TEST_COMPARE (ftw (tempdir, my_func, 20), 0);
  89
  90   free (tempdir);
  91
  92   do_cleanup ();
  93
  94   return 0;
  95 }
  96
  97 #include <support/test-driver.c>