sysdeps/mach/hurd/ifreq.c

   1 /* Fetch the host's network interface list.  Hurd version.
   2    Copyright (C) 2002-2024 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 <ifreq.h>
  20 #include <hurd.h>
  21 #include <hurd/pfinet.h>
  22 #include <sys/mman.h>
  23
  24
  25 void
  26 __ifreq (struct ifreq **ifreqs, int *num_ifs, int sockfd)
  27 {
  28   file_t server;
  29
  30   server = _hurd_socket_server (PF_INET, 0);
  31   if (server == MACH_PORT_NULL)
  32     {
  33     out:
  34       *num_ifs = 0;
  35       *ifreqs = NULL;
  36     }
  37   else
  38     {
  39       char *data = NULL;
  40       mach_msg_type_number_t len = 0;
  41       error_t err = __pfinet_siocgifconf (server, -1, &data, &len);
  42       if (err == MACH_SEND_INVALID_DEST || err == MIG_SERVER_DIED)
  43         {
  44           /* On the first use of the socket server during the operation,
  45              allow for the old server port dying.  */
  46           server = _hurd_socket_server (PF_INET, 1);
  47           if (server == MACH_PORT_NULL)
  48             goto out;
  49           err = __pfinet_siocgifconf (server, -1, (data_t *) ifreqs, &len);
  50         }
  51       if (err)
  52         goto out;
  53
  54       if (len % sizeof (struct ifreq) != 0)
  55         {
  56           __munmap (data, len);
  57           __hurd_fail (EGRATUITOUS);
  58           goto out;
  59         }
  60       *num_ifs = len / sizeof (struct ifreq);
  61       *ifreqs = (struct ifreq *) data;
  62     }
  63
  64 }