posix/spawn_faction_addclosefrom.c

   1 /* Add a closefrom to a file action list for posix_spawn.
   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 <spawn.h>
  21 #include <unistd.h>
  22 #include <spawn_int.h>
  23
  24 int
  25 __posix_spawn_file_actions_addclosefrom (posix_spawn_file_actions_t
  26                                          *file_actions, int from)
  27 {
  28 #if __SPAWN_SUPPORT_CLOSEFROM
  29   struct __spawn_action *rec;
  30
  31   if (!__spawn_valid_fd (from))
  32     return EBADF;
  33
  34   /* Allocate more memory if needed.  */
  35   if (file_actions->__used == file_actions->__allocated
  36       && __posix_spawn_file_actions_realloc (file_actions) != 0)
  37     /* This can only mean we ran out of memory.  */
  38     return ENOMEM;
  39
  40   /* Add the new value.  */
  41   rec = &file_actions->__actions[file_actions->__used];
  42   rec->tag = spawn_do_closefrom;
  43   rec->action.closefrom_action.from = from;
  44
  45   /* Account for the new entry.  */
  46   ++file_actions->__used;
  47
  48   return 0;
  49 #else
  50   return EINVAL;
  51 #endif
  52 }
  53 weak_alias (__posix_spawn_file_actions_addclosefrom,
  54             posix_spawn_file_actions_addclosefrom_np)
  55 #if !__SPAWN_SUPPORT_CLOSEFROM
  56 stub_warning (posix_spawn_file_actions_addclosefrom_np)
  57 #endif