hurd/set-host.c

   1 /* Set a host configuration item kept as the whole contents of a file.
   2    Copyright (C) 1996-2021 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 <fcntl.h>
  20 #include <hurd.h>
  21 #include "hurdhost.h"
  22
  23 ssize_t
  24 _hurd_set_host_config (const char *item, const char *value, size_t valuelen)
  25 {
  26   error_t err;
  27   mach_msg_type_number_t nwrote;
  28   file_t new, dir;
  29   char *name;
  30
  31   dir = __file_name_split (item, &name);
  32   if (dir == MACH_PORT_NULL)
  33     return -1;
  34
  35   /* Create a new node.  */
  36   err = __dir_mkfile (dir, O_WRONLY, 0644, &new);
  37   if (! err)
  38     {
  39       /* Write the contents.  */
  40       err = __io_write (new, value, valuelen, 0, &nwrote);
  41       if (! err)
  42         /* Atomically link the new node onto the name.  */
  43         err = __dir_link (dir, new, name, 0);
  44       __mach_port_deallocate (__mach_task_self (), new);
  45     }
  46   __mach_port_deallocate (__mach_task_self (), dir);
  47
  48   return err ? __hurd_fail (err) : nwrote;
  49 }