/**
 * @file
 * Ethernet output function - handles OUTGOING ethernet level traffic, implements
 * ARP resolving.
 * To be used in most low-level netif implementations
 */

/*
 * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
 * Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
 * Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
 * 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>
 *
 */

#ifndef LWIP_HDR_NETIF_ETHARP_H
#define LWIP_HDR_NETIF_ETHARP_H

#include "lwip/opt.h"

#if LWIP_ARP || LWIP_ETHERNET /* don't build if not configured for use in lwipopts.h */

#include "lwip/pbuf.h"
#include "lwip/ip4_addr.h"
#include "lwip/netif.h"
#include "lwip/ip4.h"
#include "lwip/prot/ethernet.h"

#ifdef __cplusplus
extern "C" {
#endif

#if LWIP_IPV4 && LWIP_ARP /* don't build if not configured for use in lwipopts.h */

#include "lwip/prot/etharp.h"

/** 1 seconds period */
#define ARP_TMR_INTERVAL 1000

#if ARP_QUEUEING
/** struct for queueing outgoing packets for unknown address
  * defined here to be accessed by memp.h
  */
struct etharp_q_entry {
  struct etharp_q_entry *next;
  struct pbuf *p;
};
#endif /* ARP_QUEUEING */

#define etharp_init() /* Compatibility define, no init needed. */
void etharp_tmr(void);
s8_t etharp_find_addr(struct netif *netif, const ip4_addr_t *ipaddr,
         struct eth_addr **eth_ret, const ip4_addr_t **ip_ret);
u8_t etharp_get_entry(u8_t i, ip4_addr_t **ipaddr, struct netif **netif, struct eth_addr **eth_ret);
err_t etharp_output(struct netif *netif, struct pbuf *q, const ip4_addr_t *ipaddr);
err_t etharp_query(struct netif *netif, const ip4_addr_t *ipaddr, struct pbuf *q);
err_t etharp_request(struct netif *netif, const ip4_addr_t *ipaddr);
/** For Ethernet network interfaces, we might want to send "gratuitous ARP";
 *  this is an ARP packet sent by a node in order to spontaneously cause other
 *  nodes to update an entry in their ARP cache.
 *  From RFC 3220 "IP Mobility Support for IPv4" section 4.6. */
#define etharp_gratuitous(netif) etharp_request((netif), netif_ip4_addr(netif))
void etharp_cleanup_netif(struct netif *netif);

/**
 * Update (or insert) a IP/MAC address pair in the ARP cache.
 *
 * If a pending entry is resolved, any queued packets will be sent
 * at this point.
 *
 * @param netif netif related to this entry (used for NETIF_ADDRHINT)
 * @param ipaddr IP address of the inserted ARP entry.
 * @param ethaddr Ethernet address of the inserted ARP entry.
 * @param flags See @ref etharp_state
 *
 * @return
 * - ERR_OK Successfully updated ARP cache.
 * - ERR_MEM If we could not add a new ARP entry when ETHARP_FLAG_TRY_HARD was set.
 * - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
 *
 * @see pbuf_free()
 */
err_t
etharp_update_arp_entry(struct netif *netif, const ip4_addr_t *ipaddr, struct eth_addr *ethaddr, u8_t flags);


#if ETHARP_SUPPORT_STATIC_ENTRIES
err_t etharp_add_static_entry(const ip4_addr_t *ipaddr, struct eth_addr *ethaddr);
err_t etharp_remove_static_entry(const ip4_addr_t *ipaddr);
#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */

#endif /* LWIP_IPV4 && LWIP_ARP */

void etharp_input(struct pbuf *p, struct netif *netif);

#ifdef __cplusplus
}
#endif

#endif /* LWIP_ARP || LWIP_ETHERNET */

#endif /* LWIP_HDR_NETIF_ETHARP_H */
