/* * Copyright (c) 2001-2004 Swedish Institute of Computer Science. * All rights reserved.  *  * Redistribution and use in source and binary forms, with or without modification,  * are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, *    this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright notice, *    this list of conditions and the following disclaimer in the documentation *    and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products *    derived from this software without specific prior written permission.  * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY  * OF SUCH DAMAGE. * * This file is part of the lwIP TCP/IP stack. *  * Author: Adam Dunkels <adam@sics.se> * */#include "lwip/opt.h"#if LWIP_HAVE_LOOPIF#include "netif/loopif.h"#include "lwip/mem.h"#if defined(LWIP_DEBUG) && defined(LWIP_TCPDUMP)#include "netif/tcpdump.h"#endif /* LWIP_DEBUG && LWIP_TCPDUMP */#include "lwip/tcp.h"#include "lwip/ip.h"#include "string.h"static voidloopif_input( void * arg ){	struct netif *netif = (struct netif *)( ((void **)arg)[ 0 ] );	struct pbuf *r = (struct pbuf *)( ((void **)arg)[ 1 ] );	mem_free( arg );	netif -> input( r, netif );}static err_tloopif_output(struct netif *netif, struct pbuf *p,       struct ip_addr *ipaddr){  struct pbuf *q, *r;  char *ptr;  void **arg;#if defined(LWIP_DEBUG) && defined(LWIP_TCPDUMP)  tcpdump(p);#endif /* LWIP_DEBUG && LWIP_TCPDUMP */    r = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);  if (r != NULL) {    ptr = r->payload;        for(q = p; q != NULL; q = q->next) {      memcpy(ptr, q->payload, q->len);      ptr += q->len;    }    arg = mem_malloc( sizeof( void *[2]));	if( NULL == arg ) {		return ERR_MEM;	}		arg[0] = netif;	arg[1] = r;	/**	 * workaround (patch #1779) to try to prevent bug #2595:	 * When connecting to "localhost" with the loopif interface,	 * tcp_output doesn't get the opportunity to finnish sending the	 * segment before tcp_process gets it, resulting in tcp_process	 * referencing pcb->unacked-> which still is NULL.	 * 	 * TODO: Is there still a race condition here? Leon	 */	sys_timeout( 1, loopif_input, arg );	    return ERR_OK;      }  return ERR_MEM;}err_tloopif_init(struct netif *netif){  netif->name[0] = 'l';  netif->name[1] = 'o';#if 0 /** TODO: I think this should be enabled, or not? Leon */  netif->input = loopif_input;#endif  netif->output = loopif_output;  return ERR_OK;}#endif /* LWIP_HAVE_LOOPIF */