--- /dev/null
+/**
+ * @file
+ * Ethernet Interface Skeleton
+ *
+ */
+
+/*
+ * 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>
+ *
+ */
+
+/*
+ * This file is a skeleton for developing Ethernet network interface
+ * drivers for lwIP. Add code to the low_level functions and do a
+ * search-and-replace for the word "ethernetif" to replace it with
+ * something that better describes your network interface.
+ */
+
+#include "lwip/opt.h"
+
+#if 0 /* don't build, this is only a skeleton, see previous comment */
+
+#include "lwip/def.h"
+#include "lwip/mem.h"
+#include "lwip/pbuf.h"
+#include "lwip/sys.h"
+#include <lwip/stats.h>
+#include <lwip/snmp.h>
+#include "netif/etharp.h"
+#include "netif/ppp_oe.h"
+
+/* Define those to better describe your network interface. */
+#define IFNAME0 'e'
+#define IFNAME1 'n'
+
+/**
+ * Helper struct to hold private data used to operate your ethernet interface.
+ * Keeping the ethernet address of the MAC in this struct is not necessary
+ * as it is already kept in the struct netif.
+ * But this is only an example, anyway...
+ */
+struct ethernetif {
+ struct eth_addr *ethaddr;
+ /* Add whatever per-interface state that is needed here. */
+};
+
+/* Forward declarations. */
+static void ethernetif_input(struct netif *netif);
+
+/**
+ * In this function, the hardware should be initialized.
+ * Called from ethernetif_init().
+ *
+ * @param netif the already initialized lwip network interface structure
+ * for this ethernetif
+ */
+static void
+low_level_init(struct netif *netif)
+{
+ struct ethernetif *ethernetif = netif->state;
+
+ /* set MAC hardware address length */
+ netif->hwaddr_len = ETHARP_HWADDR_LEN;
+
+ /* set MAC hardware address */
+ netif->hwaddr[0] = ;
+ ...
+ netif->hwaddr[5] = ;
+
+ /* maximum transfer unit */
+ netif->mtu = 1500;
+
+ /* device capabilities */
+ /* don't set NETIF_FLAG_ETHARP if this device is not an ethernet one */
+ netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;
+
+ /* Do whatever else is needed to initialize interface. */
+}
+
+/**
+ * This function should do the actual transmission of the packet. The packet is
+ * contained in the pbuf that is passed to the function. This pbuf
+ * might be chained.
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ * @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
+ * @return ERR_OK if the packet could be sent
+ * an err_t value if the packet couldn't be sent
+ *
+ * @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
+ * strange results. You might consider waiting for space in the DMA queue
+ * to become availale since the stack doesn't retry to send a packet
+ * dropped because of memory failure (except for the TCP timers).
+ */
+
+static err_t
+low_level_output(struct netif *netif, struct pbuf *p)
+{
+ struct ethernetif *ethernetif = netif->state;
+ struct pbuf *q;
+
+ initiate transfer();
+
+#if ETH_PAD_SIZE
+ pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
+#endif
+
+ for(q = p; q != NULL; q = q->next) {
+ /* Send the data from the pbuf to the interface, one pbuf at a
+ time. The size of the data in each pbuf is kept in the ->len
+ variable. */
+ send data from(q->payload, q->len);
+ }
+
+ signal that packet should be sent();
+
+#if ETH_PAD_SIZE
+ pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
+#endif
+
+ LINK_STATS_INC(link.xmit);
+
+ return ERR_OK;
+}
+
+/**
+ * Should allocate a pbuf and transfer the bytes of the incoming
+ * packet from the interface into the pbuf.
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ * @return a pbuf filled with the received packet (including MAC header)
+ * NULL on memory error
+ */
+static struct pbuf *
+low_level_input(struct netif *netif)
+{
+ struct ethernetif *ethernetif = netif->state;
+ struct pbuf *p, *q;
+ u16_t len;
+
+ /* Obtain the size of the packet and put it into the "len"
+ variable. */
+ len = ;
+
+#if ETH_PAD_SIZE
+ len += ETH_PAD_SIZE; /* allow room for Ethernet padding */
+#endif
+
+ /* We allocate a pbuf chain of pbufs from the pool. */
+ p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
+
+ if (p != NULL) {
+
+#if ETH_PAD_SIZE
+ pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
+#endif
+
+ /* We iterate over the pbuf chain until we have read the entire
+ * packet into the pbuf. */
+ for(q = p; q != NULL; q = q->next) {
+ /* Read enough bytes to fill this pbuf in the chain. The
+ * available data in the pbuf is given by the q->len
+ * variable. */
+ read data into(q->payload, q->len);
+ }
+ acknowledge that packet has been read();
+
+#if ETH_PAD_SIZE
+ pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
+#endif
+
+ LINK_STATS_INC(link.recv);
+ } else {
+ drop packet();
+ LINK_STATS_INC(link.memerr);
+ LINK_STATS_INC(link.drop);
+ }
+
+ return p;
+}
+
+/**
+ * This function should be called when a packet is ready to be read
+ * from the interface. It uses the function low_level_input() that
+ * should handle the actual reception of bytes from the network
+ * interface. Then the type of the received packet is determined and
+ * the appropriate input function is called.
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ */
+static void
+ethernetif_input(struct netif *netif)
+{
+ struct ethernetif *ethernetif;
+ struct eth_hdr *ethhdr;
+ struct pbuf *p;
+
+ ethernetif = netif->state;
+
+ /* move received packet into a new pbuf */
+ p = low_level_input(netif);
+ /* no packet could be read, silently ignore this */
+ if (p == NULL) return;
+ /* points to packet payload, which starts with an Ethernet header */
+ ethhdr = p->payload;
+
+ switch (htons(ethhdr->type)) {
+ /* IP or ARP packet? */
+ case ETHTYPE_IP:
+ case ETHTYPE_ARP:
+#if PPPOE_SUPPORT
+ /* PPPoE packet? */
+ case ETHTYPE_PPPOEDISC:
+ case ETHTYPE_PPPOE:
+#endif /* PPPOE_SUPPORT */
+ /* full packet send to tcpip_thread to process */
+ if (netif->input(p, netif)!=ERR_OK)
+ { LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
+ pbuf_free(p);
+ p = NULL;
+ }
+ break;
+
+ default:
+ pbuf_free(p);
+ p = NULL;
+ break;
+ }
+}
+
+/**
+ * Should be called at the beginning of the program to set up the
+ * network interface. It calls the function low_level_init() to do the
+ * actual setup of the hardware.
+ *
+ * This function should be passed as a parameter to netif_add().
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ * @return ERR_OK if the loopif is initialized
+ * ERR_MEM if private data couldn't be allocated
+ * any other err_t on error
+ */
+err_t
+ethernetif_init(struct netif *netif)
+{
+ struct ethernetif *ethernetif;
+
+ LWIP_ASSERT("netif != NULL", (netif != NULL));
+
+ ethernetif = mem_malloc(sizeof(struct ethernetif));
+ if (ethernetif == NULL) {
+ LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_init: out of memory\n"));
+ return ERR_MEM;
+ }
+
+#if LWIP_NETIF_HOSTNAME
+ /* Initialize interface hostname */
+ netif->hostname = "lwip";
+#endif /* LWIP_NETIF_HOSTNAME */
+
+ /*
+ * Initialize the snmp variables and counters inside the struct netif.
+ * The last argument should be replaced with your link speed, in units
+ * of bits per second.
+ */
+ NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, ???);
+
+ netif->state = ethernetif;
+ netif->name[0] = IFNAME0;
+ netif->name[1] = IFNAME1;
+ /* We directly use etharp_output() here to save a function call.
+ * You can instead declare your own function an call etharp_output()
+ * from it if you have to do some checks before sending (e.g. if link
+ * is available...) */
+ netif->output = etharp_output;
+ netif->linkoutput = low_level_output;
+
+ ethernetif->ethaddr = (struct eth_addr *)&(netif->hwaddr[0]);
+
+ /* initialize the hardware */
+ low_level_init(netif);
+
+ return ERR_OK;
+}
+
+#endif /* 0 */
