lwip/netif/loopif.c

0001 /**
0002  * @file
0003  * Loop Interface
0004  *
0005  */
0006
0007 /*
0008  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
0009  * All rights reserved.
0010  *
0011  * Redistribution and use in source and binary forms, with or without modification,
0012  * are permitted provided that the following conditions are met:
0013  *
0014  * 1. Redistributions of source code must retain the above copyright notice,
0015  *    this list of conditions and the following disclaimer.
0016  * 2. Redistributions in binary form must reproduce the above copyright notice,
0017  *    this list of conditions and the following disclaimer in the documentation
0018  *    and/or other materials provided with the distribution.
0019  * 3. The name of the author may not be used to endorse or promote products
0020  *    derived from this software without specific prior written permission.
0021  *
0022  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
0023  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
0024  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
0025  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
0026  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
0027  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0028  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0029  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
0030  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
0031  * OF SUCH DAMAGE.
0032  *
0033  * This file is part of the lwIP TCP/IP stack.
0034  *
0035  * Author: Adam Dunkels <adam@sics.se>
0036  *
0037  */
0038 #include "lwip/opt.h"
0039
0040 #if LWIP_HAVE_LOOPIF
0041
0042 #include "netif/loopif.h"
0043 #include "lwip/snmp.h"
0044
0045 /**
0046  * Initialize a lwip network interface structure for a loopback interface
0047  *
0048  * @param netif the lwip network interface structure for this loopif
0049  * @return ERR_OK if the loopif is initialized
0050  *         ERR_MEM if private data couldn't be allocated
0051  */
0052 err_t
0053 loopif_init(struct netif *netif)
0054 {
0055   /* initialize the snmp variables and counters inside the struct netif
0056    * ifSpeed: no assumption can be made!
0057    */
0058   NETIF_INIT_SNMP(netif, snmp_ifType_softwareLoopback, 0);
0059
0060   netif->name[0] = 'l';
0061   netif->name[1] = 'o';
0062   netif->output = netif_loop_output;
0063   return ERR_OK;
0064 }
0065
0066 #endif /* LWIP_HAVE_LOOPIF */