manual/examples/mkdirent.c

   1 /* Example for creating a struct dirent object for use with glob.
   2    Copyright (C) 2016-2022 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU General Public License
   6    as published by the Free Software Foundation; either version 2
   7    of the License, or (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, see <https://www.gnu.org/licenses/>.
  16 */
  17
  18 #include <dirent.h>
  19 #include <errno.h>
  20 #include <stddef.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23
  24 struct dirent *
  25 mkdirent (const char *name)
  26 {
  27   size_t dirent_size = offsetof (struct dirent, d_name) + 1;
  28   size_t name_length = strlen (name);
  29   size_t total_size = dirent_size + name_length;
  30   if (total_size < dirent_size)
  31     {
  32       errno = ENOMEM;
  33       return NULL;
  34     }
  35   struct dirent *result = malloc (total_size);
  36   if (result == NULL)
  37     return NULL;
  38   result->d_type = DT_UNKNOWN;
  39   result->d_ino = 1;            /* Do not skip this entry.  */
  40   memcpy (result->d_name, name, name_length + 1);
  41   return result;
  42 }