src/net/nullnet.c

   1 /*
   2  * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
   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 as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * 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, write to the Free Software
  16  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17  */
  18
  19 #include <stdint.h>
  20 #include <errno.h>
  21 #include <gpxe/iobuf.h>
  22 #include <gpxe/netdevice.h>
  23
  24 /** @file
  25  *
  26  * Null network device
  27  *
  28  */
  29
  30 static int null_open ( struct net_device *netdev __unused ) {
  31         return -ENODEV;
  32 };
  33
  34 static void null_close ( struct net_device *netdev __unused ) {
  35         /* Do nothing */
  36 };
  37
  38 static int null_transmit ( struct net_device *netdev __unused,
  39                            struct io_buffer *iobuf __unused ) {
  40         return -ENODEV;
  41 };
  42
  43 static void null_poll ( struct net_device *netdev __unused ) {
  44         /* Do nothing */
  45 }
  46
  47 static void null_irq ( struct net_device *netdev __unused,
  48                        int enable __unused ) {
  49         /* Do nothing */
  50 }
  51
  52 struct net_device_operations null_netdev_operations = {
  53         .open           = null_open,
  54         .close          = null_close,
  55         .transmit       = null_transmit,
  56         .poll           = null_poll,
  57         .irq            = null_irq,
  58 };