Copy of NetServicesMin with the HTTP Client library. Includes modification for HTTP servers which send the HTTP status line in its own packet.
lwip/core/netif.c
- Committer:
- andrewbonney
- Date:
- 2011-05-26
- Revision:
- 0:18dd877d2c77
File content as of revision 0:18dd877d2c77:
/** * @file * lwIP network interface abstraction * */ /* * 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" #include "lwip/def.h" #include "lwip/ip_addr.h" #include "lwip/netif.h" #include "lwip/tcp_impl.h" #include "lwip/snmp.h" #include "lwip/igmp.h" #include "netif/etharp.h" #include "lwip/stats.h" #if ENABLE_LOOPBACK #include "lwip/sys.h" #if LWIP_NETIF_LOOPBACK_MULTITHREADING #include "lwip/tcpip.h" #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */ #endif /* ENABLE_LOOPBACK */ #if LWIP_AUTOIP #include "lwip/autoip.h" #endif /* LWIP_AUTOIP */ #if LWIP_DHCP #include "lwip/dhcp.h" #endif /* LWIP_DHCP */ #if LWIP_NETIF_STATUS_CALLBACK #define NETIF_STATUS_CALLBACK(n) do{ if (n->status_callback) { (n->status_callback)(n); }}while(0) #else #define NETIF_STATUS_CALLBACK(n) #endif /* LWIP_NETIF_STATUS_CALLBACK */ #if LWIP_NETIF_LINK_CALLBACK #define NETIF_LINK_CALLBACK(n) do{ if (n->link_callback) { (n->link_callback)(n); }}while(0) #else #define NETIF_LINK_CALLBACK(n) #endif /* LWIP_NETIF_LINK_CALLBACK */ struct netif *netif_list; struct netif *netif_default; #if LWIP_HAVE_LOOPIF static struct netif loop_netif; /** * Initialize a lwip network interface structure for a loopback interface * * @param netif the lwip network interface structure for this loopif * @return ERR_OK if the loopif is initialized * ERR_MEM if private data couldn't be allocated */ static err_t netif_loopif_init(struct netif *netif) { /* initialize the snmp variables and counters inside the struct netif * ifSpeed: no assumption can be made! */ NETIF_INIT_SNMP(netif, snmp_ifType_softwareLoopback, 0); netif->name[0] = 'l'; netif->name[1] = 'o'; netif->output = netif_loop_output; return ERR_OK; } #endif /* LWIP_HAVE_LOOPIF */ void netif_init(void) { #if LWIP_HAVE_LOOPIF ip_addr_t loop_ipaddr, loop_netmask, loop_gw; IP4_ADDR(&loop_gw, 127,0,0,1); IP4_ADDR(&loop_ipaddr, 127,0,0,1); IP4_ADDR(&loop_netmask, 255,0,0,0); #if NO_SYS netif_add(&loop_netif, &loop_ipaddr, &loop_netmask, &loop_gw, NULL, netif_loopif_init, ip_input); #else /* NO_SYS */ netif_add(&loop_netif, &loop_ipaddr, &loop_netmask, &loop_gw, NULL, netif_loopif_init, tcpip_input); #endif /* NO_SYS */ netif_set_up(&loop_netif); #endif /* LWIP_HAVE_LOOPIF */ } /** * Add a network interface to the list of lwIP netifs. * * @param netif a pre-allocated netif structure * @param ipaddr IP address for the new netif * @param netmask network mask for the new netif * @param gw default gateway IP address for the new netif * @param state opaque data passed to the new netif * @param init callback function that initializes the interface * @param input callback function that is called to pass * ingress packets up in the protocol layer stack. * * @return netif, or NULL if failed. */ struct netif * netif_add(struct netif *netif, ip_addr_t *ipaddr, ip_addr_t *netmask, ip_addr_t *gw, void *state, netif_init_fn init, netif_input_fn input) { static u8_t netifnum = 0; LWIP_ASSERT("No init function given", init != NULL); /* reset new interface configuration state */ ip_addr_set_zero(&netif->ip_addr); ip_addr_set_zero(&netif->netmask); ip_addr_set_zero(&netif->gw); netif->flags = 0; #if LWIP_DHCP /* netif not under DHCP control by default */ netif->dhcp = NULL; #endif /* LWIP_DHCP */ #if LWIP_AUTOIP /* netif not under AutoIP control by default */ netif->autoip = NULL; #endif /* LWIP_AUTOIP */ #if LWIP_NETIF_STATUS_CALLBACK netif->status_callback = NULL; #endif /* LWIP_NETIF_STATUS_CALLBACK */ #if LWIP_NETIF_LINK_CALLBACK netif->link_callback = NULL; #endif /* LWIP_NETIF_LINK_CALLBACK */ #if LWIP_IGMP netif->igmp_mac_filter = NULL; #endif /* LWIP_IGMP */ #if ENABLE_LOOPBACK netif->loop_first = NULL; netif->loop_last = NULL; #endif /* ENABLE_LOOPBACK */ /* remember netif specific state information data */ netif->state = state; netif->num = netifnum++; netif->input = input; #if LWIP_NETIF_HWADDRHINT netif->addr_hint = NULL; #endif /* LWIP_NETIF_HWADDRHINT*/ #if ENABLE_LOOPBACK && LWIP_LOOPBACK_MAX_PBUFS netif->loop_cnt_current = 0; #endif /* ENABLE_LOOPBACK && LWIP_LOOPBACK_MAX_PBUFS */ netif_set_addr(netif, ipaddr, netmask, gw); /* call user specified initialization function for netif */ if (init(netif) != ERR_OK) { return NULL; } /* add this netif to the list */ netif->next = netif_list; netif_list = netif; snmp_inc_iflist(); #if LWIP_IGMP /* start IGMP processing */ if (netif->flags & NETIF_FLAG_IGMP) { igmp_start(netif); } #endif /* LWIP_IGMP */ LWIP_DEBUGF(NETIF_DEBUG, ("netif: added interface %c%c IP addr ", netif->name[0], netif->name[1])); ip_addr_debug_print(NETIF_DEBUG, ipaddr); LWIP_DEBUGF(NETIF_DEBUG, (" netmask ")); ip_addr_debug_print(NETIF_DEBUG, netmask); LWIP_DEBUGF(NETIF_DEBUG, (" gw ")); ip_addr_debug_print(NETIF_DEBUG, gw); LWIP_DEBUGF(NETIF_DEBUG, ("\n")); return netif; } /** * Change IP address configuration for a network interface (including netmask * and default gateway). * * @param netif the network interface to change * @param ipaddr the new IP address * @param netmask the new netmask * @param gw the new default gateway */ void netif_set_addr(struct netif *netif, ip_addr_t *ipaddr, ip_addr_t *netmask, ip_addr_t *gw) { netif_set_ipaddr(netif, ipaddr); netif_set_netmask(netif, netmask); netif_set_gw(netif, gw); } /** * Remove a network interface from the list of lwIP netifs. * * @param netif the network interface to remove */ void netif_remove(struct netif *netif) { if (netif == NULL) { return; } #if LWIP_IGMP /* stop IGMP processing */ if (netif->flags & NETIF_FLAG_IGMP) { igmp_stop(netif); } #endif /* LWIP_IGMP */ if (netif_is_up(netif)) { /* set netif down before removing (call callback function) */ netif_set_down(netif); } snmp_delete_ipaddridx_tree(netif); /* is it the first netif? */ if (netif_list == netif) { netif_list = netif->next; } else { /* look for netif further down the list */ struct netif * tmpNetif; for (tmpNetif = netif_list; tmpNetif != NULL; tmpNetif = tmpNetif->next) { if (tmpNetif->next == netif) { tmpNetif->next = netif->next; break; } } if (tmpNetif == NULL) return; /* we didn't find any netif today */ } snmp_dec_iflist(); /* this netif is default? */ if (netif_default == netif) { /* reset default netif */ netif_set_default(NULL); } LWIP_DEBUGF( NETIF_DEBUG, ("netif_remove: removed netif\n") ); } /** * Find a network interface by searching for its name * * @param name the name of the netif (like netif->name) plus concatenated number * in ascii representation (e.g. 'en0') */ struct netif * netif_find(char *name) { struct netif *netif; u8_t num; if (name == NULL) { return NULL; } num = name[2] - '0'; for(netif = netif_list; netif != NULL; netif = netif->next) { if (num == netif->num && name[0] == netif->name[0] && name[1] == netif->name[1]) { LWIP_DEBUGF(NETIF_DEBUG, ("netif_find: found %c%c\n", name[0], name[1])); return netif; } } LWIP_DEBUGF(NETIF_DEBUG, ("netif_find: didn't find %c%c\n", name[0], name[1])); return NULL; } /** * Change the IP address of a network interface * * @param netif the network interface to change * @param ipaddr the new IP address * * @note call netif_set_addr() if you also want to change netmask and * default gateway */ void netif_set_ipaddr(struct netif *netif, ip_addr_t *ipaddr) { /* TODO: Handling of obsolete pcbs */ /* See: http://mail.gnu.org/archive/html/lwip-users/2003-03/msg00118.html */ #if LWIP_TCP struct tcp_pcb *pcb; struct tcp_pcb_listen *lpcb; /* address is actually being changed? */ if ((ip_addr_cmp(ipaddr, &(netif->ip_addr))) == 0) { /* extern struct tcp_pcb *tcp_active_pcbs; defined by tcp.h */ LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_set_ipaddr: netif address being changed\n")); pcb = tcp_active_pcbs; while (pcb != NULL) { /* PCB bound to current local interface address? */ if (ip_addr_cmp(&(pcb->local_ip), &(netif->ip_addr)) #if LWIP_AUTOIP /* connections to link-local addresses must persist (RFC3927 ch. 1.9) */ && !ip_addr_islinklocal(&(pcb->local_ip)) #endif /* LWIP_AUTOIP */ ) { /* this connection must be aborted */ struct tcp_pcb *next = pcb->next; LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_STATE, ("netif_set_ipaddr: aborting TCP pcb %p\n", (void *)pcb)); tcp_abort(pcb); pcb = next; } else { pcb = pcb->next; } } for (lpcb = tcp_listen_pcbs.listen_pcbs; lpcb != NULL; lpcb = lpcb->next) { /* PCB bound to current local interface address? */ if ((!(ip_addr_isany(&(lpcb->local_ip)))) && (ip_addr_cmp(&(lpcb->local_ip), &(netif->ip_addr)))) { /* The PCB is listening to the old ipaddr and * is set to listen to the new one instead */ ip_addr_set(&(lpcb->local_ip), ipaddr); } } } #endif snmp_delete_ipaddridx_tree(netif); snmp_delete_iprteidx_tree(0,netif); /* set new IP address to netif */ ip_addr_set(&(netif->ip_addr), ipaddr); snmp_insert_ipaddridx_tree(netif); snmp_insert_iprteidx_tree(0,netif); LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: IP address of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", netif->name[0], netif->name[1], ip4_addr1_16(&netif->ip_addr), ip4_addr2_16(&netif->ip_addr), ip4_addr3_16(&netif->ip_addr), ip4_addr4_16(&netif->ip_addr))); } /** * Change the default gateway for a network interface * * @param netif the network interface to change * @param gw the new default gateway * * @note call netif_set_addr() if you also want to change ip address and netmask */ void netif_set_gw(struct netif *netif, ip_addr_t *gw) { ip_addr_set(&(netif->gw), gw); LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: GW address of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", netif->name[0], netif->name[1], ip4_addr1_16(&netif->gw), ip4_addr2_16(&netif->gw), ip4_addr3_16(&netif->gw), ip4_addr4_16(&netif->gw))); } /** * Change the netmask of a network interface * * @param netif the network interface to change * @param netmask the new netmask * * @note call netif_set_addr() if you also want to change ip address and * default gateway */ void netif_set_netmask(struct netif *netif, ip_addr_t *netmask) { snmp_delete_iprteidx_tree(0, netif); /* set new netmask to netif */ ip_addr_set(&(netif->netmask), netmask); snmp_insert_iprteidx_tree(0, netif); LWIP_DEBUGF(NETIF_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("netif: netmask of interface %c%c set to %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n", netif->name[0], netif->name[1], ip4_addr1_16(&netif->netmask), ip4_addr2_16(&netif->netmask), ip4_addr3_16(&netif->netmask), ip4_addr4_16(&netif->netmask))); } /** * Set a network interface as the default network interface * (used to output all packets for which no specific route is found) * * @param netif the default network interface */ void netif_set_default(struct netif *netif) { if (netif == NULL) { /* remove default route */ snmp_delete_iprteidx_tree(1, netif); } else { /* install default route */ snmp_insert_iprteidx_tree(1, netif); } netif_default = netif; LWIP_DEBUGF(NETIF_DEBUG, ("netif: setting default interface %c%c\n", netif ? netif->name[0] : '\'', netif ? netif->name[1] : '\'')); } /** * Bring an interface up, available for processing * traffic. * * @note: Enabling DHCP on a down interface will make it come * up once configured. * * @see dhcp_start() */ void netif_set_up(struct netif *netif) { if (!(netif->flags & NETIF_FLAG_UP)) { netif->flags |= NETIF_FLAG_UP; #if LWIP_SNMP snmp_get_sysuptime(&netif->ts); #endif /* LWIP_SNMP */ NETIF_STATUS_CALLBACK(netif); if (netif->flags & NETIF_FLAG_LINK_UP) { #if LWIP_ARP /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */ if (netif->flags & (NETIF_FLAG_ETHARP)) { etharp_gratuitous(netif); } #endif /* LWIP_ARP */ #if LWIP_IGMP /* resend IGMP memberships */ if (netif->flags & NETIF_FLAG_IGMP) { igmp_report_groups( netif); } #endif /* LWIP_IGMP */ } } } /** * Bring an interface down, disabling any traffic processing. * * @note: Enabling DHCP on a down interface will make it come * up once configured. * * @see dhcp_start() */ void netif_set_down(struct netif *netif) { if (netif->flags & NETIF_FLAG_UP) { netif->flags &= ~NETIF_FLAG_UP; #if LWIP_SNMP snmp_get_sysuptime(&netif->ts); #endif NETIF_STATUS_CALLBACK(netif); } } #if LWIP_NETIF_STATUS_CALLBACK /** * Set callback to be called when interface is brought up/down */ void netif_set_status_callback(struct netif *netif, netif_status_callback_fn status_callback) { if (netif) { netif->status_callback = status_callback; } } #endif /* LWIP_NETIF_STATUS_CALLBACK */ /** * Called by a driver when its link goes up */ void netif_set_link_up(struct netif *netif ) { if (!(netif->flags & NETIF_FLAG_LINK_UP)) { netif->flags |= NETIF_FLAG_LINK_UP; #if LWIP_DHCP if (netif->dhcp) { dhcp_network_changed(netif); } #endif /* LWIP_DHCP */ #if LWIP_AUTOIP if (netif->autoip) { autoip_network_changed(netif); } #endif /* LWIP_AUTOIP */ if (netif->flags & NETIF_FLAG_UP) { #if LWIP_ARP /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */ if (netif->flags & NETIF_FLAG_ETHARP) { etharp_gratuitous(netif); } #endif /* LWIP_ARP */ #if LWIP_IGMP /* resend IGMP memberships */ if (netif->flags & NETIF_FLAG_IGMP) { igmp_report_groups( netif); } #endif /* LWIP_IGMP */ } NETIF_LINK_CALLBACK(netif); } } /** * Called by a driver when its link goes down */ void netif_set_link_down(struct netif *netif ) { if (netif->flags & NETIF_FLAG_LINK_UP) { netif->flags &= ~NETIF_FLAG_LINK_UP; NETIF_LINK_CALLBACK(netif); } } #if LWIP_NETIF_LINK_CALLBACK /** * Set callback to be called when link is brought up/down */ void netif_set_link_callback(struct netif *netif, netif_status_callback_fn link_callback) { if (netif) { netif->link_callback = link_callback; } } #endif /* LWIP_NETIF_LINK_CALLBACK */ #if ENABLE_LOOPBACK /** * Send an IP packet to be received on the same netif (loopif-like). * The pbuf is simply copied and handed back to netif->input. * In multithreaded mode, this is done directly since netif->input must put * the packet on a queue. * In callback mode, the packet is put on an internal queue and is fed to * netif->input by netif_poll(). * * @param netif the lwip network interface structure * @param p the (IP) packet to 'send' * @param ipaddr the ip address to send the packet to (not used) * @return ERR_OK if the packet has been sent * ERR_MEM if the pbuf used to copy the packet couldn't be allocated */ err_t netif_loop_output(struct netif *netif, struct pbuf *p, ip_addr_t *ipaddr) { struct pbuf *r; err_t err; struct pbuf *last; #if LWIP_LOOPBACK_MAX_PBUFS u8_t clen = 0; #endif /* LWIP_LOOPBACK_MAX_PBUFS */ /* If we have a loopif, SNMP counters are adjusted for it, * if not they are adjusted for 'netif'. */ #if LWIP_SNMP #if LWIP_HAVE_LOOPIF struct netif *stats_if = &loop_netif; #else /* LWIP_HAVE_LOOPIF */ struct netif *stats_if = netif; #endif /* LWIP_HAVE_LOOPIF */ #endif /* LWIP_SNMP */ SYS_ARCH_DECL_PROTECT(lev); LWIP_UNUSED_ARG(ipaddr); /* Allocate a new pbuf */ r = pbuf_alloc(PBUF_LINK, p->tot_len, PBUF_RAM); if (r == NULL) { LINK_STATS_INC(link.memerr); LINK_STATS_INC(link.drop); snmp_inc_ifoutdiscards(stats_if); return ERR_MEM; } #if LWIP_LOOPBACK_MAX_PBUFS clen = pbuf_clen(r); /* check for overflow or too many pbuf on queue */ if(((netif->loop_cnt_current + clen) < netif->loop_cnt_current) || ((netif->loop_cnt_current + clen) > LWIP_LOOPBACK_MAX_PBUFS)) { pbuf_free(r); LINK_STATS_INC(link.memerr); LINK_STATS_INC(link.drop); snmp_inc_ifoutdiscards(stats_if); return ERR_MEM; } netif->loop_cnt_current += clen; #endif /* LWIP_LOOPBACK_MAX_PBUFS */ /* Copy the whole pbuf queue p into the single pbuf r */ if ((err = pbuf_copy(r, p)) != ERR_OK) { pbuf_free(r); LINK_STATS_INC(link.memerr); LINK_STATS_INC(link.drop); snmp_inc_ifoutdiscards(stats_if); return err; } /* Put the packet on a linked list which gets emptied through calling netif_poll(). */ /* let last point to the last pbuf in chain r */ for (last = r; last->next != NULL; last = last->next); SYS_ARCH_PROTECT(lev); if(netif->loop_first != NULL) { LWIP_ASSERT("if first != NULL, last must also be != NULL", netif->loop_last != NULL); netif->loop_last->next = r; netif->loop_last = last; } else { netif->loop_first = r; netif->loop_last = last; } SYS_ARCH_UNPROTECT(lev); LINK_STATS_INC(link.xmit); snmp_add_ifoutoctets(stats_if, p->tot_len); snmp_inc_ifoutucastpkts(stats_if); #if LWIP_NETIF_LOOPBACK_MULTITHREADING /* For multithreading environment, schedule a call to netif_poll */ tcpip_callback((tcpip_callback_fn)netif_poll, netif); #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */ return ERR_OK; } /** * Call netif_poll() in the main loop of your application. This is to prevent * reentering non-reentrant functions like tcp_input(). Packets passed to * netif_loop_output() are put on a list that is passed to netif->input() by * netif_poll(). */ void netif_poll(struct netif *netif) { struct pbuf *in; /* If we have a loopif, SNMP counters are adjusted for it, * if not they are adjusted for 'netif'. */ #if LWIP_SNMP #if LWIP_HAVE_LOOPIF struct netif *stats_if = &loop_netif; #else /* LWIP_HAVE_LOOPIF */ struct netif *stats_if = netif; #endif /* LWIP_HAVE_LOOPIF */ #endif /* LWIP_SNMP */ SYS_ARCH_DECL_PROTECT(lev); do { /* Get a packet from the list. With SYS_LIGHTWEIGHT_PROT=1, this is protected */ SYS_ARCH_PROTECT(lev); in = netif->loop_first; if (in != NULL) { struct pbuf *in_end = in; #if LWIP_LOOPBACK_MAX_PBUFS u8_t clen = pbuf_clen(in); /* adjust the number of pbufs on queue */ LWIP_ASSERT("netif->loop_cnt_current underflow", ((netif->loop_cnt_current - clen) < netif->loop_cnt_current)); netif->loop_cnt_current -= clen; #endif /* LWIP_LOOPBACK_MAX_PBUFS */ while (in_end->len != in_end->tot_len) { LWIP_ASSERT("bogus pbuf: len != tot_len but next == NULL!", in_end->next != NULL); in_end = in_end->next; } /* 'in_end' now points to the last pbuf from 'in' */ if (in_end == netif->loop_last) { /* this was the last pbuf in the list */ netif->loop_first = netif->loop_last = NULL; } else { /* pop the pbuf off the list */ netif->loop_first = in_end->next; LWIP_ASSERT("should not be null since first != last!", netif->loop_first != NULL); } /* De-queue the pbuf from its successors on the 'loop_' list. */ in_end->next = NULL; } SYS_ARCH_UNPROTECT(lev); if (in != NULL) { LINK_STATS_INC(link.recv); snmp_add_ifinoctets(stats_if, in->tot_len); snmp_inc_ifinucastpkts(stats_if); /* loopback packets are always IP packets! */ if (ip_input(in, netif) != ERR_OK) { pbuf_free(in); } /* Don't reference the packet any more! */ in = NULL; } /* go on while there is a packet on the list */ } while (netif->loop_first != NULL); } #if !LWIP_NETIF_LOOPBACK_MULTITHREADING /** * Calls netif_poll() for every netif on the netif_list. */ void netif_poll_all(void) { struct netif *netif = netif_list; /* loop through netifs */ while (netif != NULL) { netif_poll(netif); /* proceed to next network interface */ netif = netif->next; } } #endif /* !LWIP_NETIF_LOOPBACK_MULTITHREADING */ #endif /* ENABLE_LOOPBACK */