/*
 * Copyright (c) 2001,2002 Florian Schulze.
 * 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. Neither the name of the authors nor the names of the contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``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 AUTHORS OR CONTRIBUTORS 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.
 *
 * pktif.c - This file is part of lwIP pktif
 *
 ****************************************************************************
 *
 * This file is derived from an example in lwIP with the following license:
 *
 * Copyright (c) 2001, 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. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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.
 *
 */

#include "lwip/opt.h"

#if LWIP_ETHERNET

#include "pktif.h"

/* get the windows definitions of the following 4 functions out of the way */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "lwip/debug.h"

#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/pbuf.h"
#include "lwip/stats.h"
#include "lwip/sys.h"
#include "lwip/ip.h"
#include "lwip/snmp.h"
#include "lwip/tcpip.h"

#include "netif/etharp.h"
#include "pktdrv.h"

/* include the port-dependent configuration */
#include "lwipcfg_msvc.h"

/* Define those to better describe your network interface.
   For now, we use 'e0', 'e1', 'e2' and so on */
#define IFNAME0               'e'
#define IFNAME1               '0'

/* index of the network adapter to use for lwIP */
#ifndef PACKET_LIB_ADAPTER_NR
#define PACKET_LIB_ADAPTER_NR  0
#endif

/* Define PHY delay when "link up" */
#ifndef PHY_LINKUP_DELAY
#define PHY_LINKUP_DELAY       5000
#endif

/* link state notification macro */
#if NO_SYS
#define NOTIFY_LINKSTATE(netif, linkfunc) linkfunc(netif)
#else  /* NO_SYS*/
#define NOTIFY_LINKSTATE(netif, linkfunc) tcpip_timeout(PHY_LINKUP_DELAY, (sys_timeout_handler)linkfunc, netif)
#endif /* NO_SYS*/

/* Forward declarations. */
void ethernetif_process_input(void *arg, void *packet, int len);

/*-----------------------------------------------------------------------------------*/
static void
low_level_init(struct netif *netif)
{
  char adapter_mac_addr[ETHARP_HWADDR_LEN];
  u8_t my_mac_addr[ETHARP_HWADDR_LEN] = LWIP_MAC_ADDR_BASE;
  int adapter_num = PACKET_LIB_ADAPTER_NR;
  enum link_adapter_event linkstate;

#ifdef PACKET_LIB_ADAPTER_GUID
  /* get adapter index for guid string */
  adapter_num = get_adapter_index(PACKET_LIB_ADAPTER_GUID);
  if (adapter_num < 0) {
    printf("ERROR finding network adapter with GUID \"%s\"!\n", PACKET_LIB_ADAPTER_GUID);
    LWIP_ASSERT("ERROR initializing network adapter!\n", 0);
    return;
  }
#endif /* PACKET_LIB_ADAPTER_GUID */

  /* Do whatever else is needed to initialize interface. */
  if ((netif->state = init_adapter(adapter_num, adapter_mac_addr,
                      ethernetif_process_input, netif, &linkstate)) == NULL) {
    printf("ERROR initializing network adapter %d!\n", PACKET_LIB_ADAPTER_NR);
    LWIP_ASSERT("ERROR initializing network adapter!\n", 0);
    return;
  }

  /* change the MAC address to a unique value
     so that multiple ethernetifs are supported */
  my_mac_addr[ETHARP_HWADDR_LEN - 1] += netif->num;
  /* Copy MAC addr */
  memcpy(&netif->hwaddr, my_mac_addr, ETHARP_HWADDR_LEN);

  if (linkstate == LINKEVENT_UP) {
    netif_set_link_up(netif);
  } else {
    netif_set_link_down(netif);
  }

  LWIP_DEBUGF(NETIF_DEBUG, ("pktif: eth_addr %02X%02X%02X%02X%02X%02X\n",netif->hwaddr[0],netif->hwaddr[1],netif->hwaddr[2],netif->hwaddr[3],netif->hwaddr[4],netif->hwaddr[5]));
}

/*-----------------------------------------------------------------------------------*/
/*
 * low_level_output():
 *
 * 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.
 *
 */
/*-----------------------------------------------------------------------------------*/
static err_t
low_level_output(struct netif *netif, struct pbuf *p)
{
  struct pbuf *q;
  unsigned char buffer[1600];
  unsigned char *ptr;
  struct eth_hdr *ethhdr;

#if defined(LWIP_DEBUG) && LWIP_NETIF_TX_SINGLE_PBUF
  LWIP_ASSERT("p->next == NULL && p->len == p->tot_len", p->next == NULL && p->len == p->tot_len);
#endif

  /* initiate transfer(); */
  if (p->tot_len >= sizeof(buffer)) {
    LINK_STATS_INC(link.lenerr);
    LINK_STATS_INC(link.drop);
    snmp_inc_ifoutdiscards(netif);
    return ERR_BUF;
  }
  ptr = buffer;
  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); */
    LWIP_DEBUGF(NETIF_DEBUG, ("netif: send ptr %p q->payload %p q->len %i q->next %p\n", ptr, q->payload, (int)q->len, q->next));
    memcpy(ptr, q->payload, q->len);
    ptr += q->len;
  }

  /* signal that packet should be sent(); */
  if (packet_send(netif->state, buffer, p->tot_len) < 0) {
    LINK_STATS_INC(link.memerr);
    LINK_STATS_INC(link.drop);
    snmp_inc_ifoutdiscards(netif);
    return ERR_BUF;
  }

  LINK_STATS_INC(link.xmit);
  snmp_add_ifoutoctets(netif, p->tot_len);
  ethhdr = (struct eth_hdr *)p->payload;
  if ((ethhdr->dest.addr[0] & 1) != 0) {
    /* broadcast or multicast packet*/
    snmp_inc_ifoutnucastpkts(netif);
  } else {
    /* unicast packet */
    snmp_inc_ifoutucastpkts(netif);
  }
  return ERR_OK;
}

/*-----------------------------------------------------------------------------------*/
/*
 * low_level_input():
 *
 * Should allocate a pbuf and transfer the bytes of the incoming
 * packet from the interface into the pbuf.
 *
 */
/*-----------------------------------------------------------------------------------*/
static struct pbuf *
low_level_input(struct netif *netif, void *packet, int packet_len)
{
  struct pbuf *p, *q;
  int start;
  int length = packet_len;
  struct eth_hdr *ethhdr = (struct eth_hdr*)packet;
  int unicast;

  /* MAC filter: only let my MAC or non-unicast through */
  unicast = ((ethhdr->dest.addr[0] & 0x01) == 0);
  if (((memcmp(&ethhdr->dest, &netif->hwaddr, ETHARP_HWADDR_LEN)) && unicast) ||
      /* and don't let feedback packets through (limitation in winpcap?) */
      (!memcmp(&ethhdr->src, netif->hwaddr, ETHARP_HWADDR_LEN))) {
    /* don't update counters here! */
    return NULL;
  }

  /* We allocate a pbuf chain of pbufs from the pool. */
  p = pbuf_alloc(PBUF_RAW, (u16_t)length, PBUF_POOL);
  LWIP_DEBUGF(NETIF_DEBUG, ("netif: recv length %i p->tot_len %i\n", length, (int)p->tot_len));
  
  if (p != NULL) {
    /* We iterate over the pbuf chain until we have read the entire
       packet into the pbuf. */
    start=0;
    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); */
      LWIP_DEBUGF(NETIF_DEBUG, ("netif: recv start %i length %i q->payload %p q->len %i q->next %p\n", start, length, q->payload, (int)q->len, q->next));
      memcpy(q->payload, &((char*)packet)[start], q->len);
      start += q->len;
      length -= q->len;
      if (length <= 0) {
        break;
      }
    }
    LINK_STATS_INC(link.recv);
    snmp_add_ifinoctets(netif, p->tot_len);
    if (unicast) {
      snmp_inc_ifinucastpkts(netif);
    } else {
      snmp_inc_ifinnucastpkts(netif);
    }
  } else {
    /* drop packet(); */
    LINK_STATS_INC(link.memerr);
    LINK_STATS_INC(link.drop);
  }

  return p;
}

/*-----------------------------------------------------------------------------------*/
/*
 * ethernetif_input():
 *
 * 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.
 *
 */
/*-----------------------------------------------------------------------------------*/
static void
ethernetif_input(struct netif *netif, void *packet, int packet_len)
{
  struct eth_hdr *ethhdr;
  struct pbuf *p;

  if (packet_len <= 0) {
    return;
  }
  /* move received packet into a new pbuf */
  p = low_level_input(netif, packet, packet_len);
  /* no packet could be read, silently ignore this */
  if (p == NULL) {
    return;
  }

  /* points to packet payload, which starts with an Ethernet header */
  ethhdr = (struct eth_hdr *)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:
    LINK_STATS_INC(link.proterr);
    LINK_STATS_INC(link.drop);
    pbuf_free(p);
    p = NULL;
    break;
  }
}

/*-----------------------------------------------------------------------------------*/
/*
 * ethernetif_init():
 *
 * 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.
 *
 */
/*-----------------------------------------------------------------------------------*/
err_t
ethernetif_init(struct netif *netif)
{
  static int ethernetif_index;

  int local_index;
  SYS_ARCH_DECL_PROTECT(lev);
  SYS_ARCH_PROTECT(lev);
  local_index = ethernetif_index++;
  SYS_ARCH_UNPROTECT(lev);

  netif->name[0] = IFNAME0;
  netif->name[1] = (char)(IFNAME1 + local_index);
  netif->linkoutput = low_level_output;
#if LWIP_ARP
  netif->output = etharp_output;
#else /* LWIP_ARP */
  netif->output = NULL; /* not used for PPPoE */
#endif /* LWIP_ARP */
#if LWIP_NETIF_HOSTNAME
  /* Initialize interface hostname */
  netif_set_hostname(netif, "lwip");
#endif /* LWIP_NETIF_HOSTNAME */

  netif->mtu = 1500;
  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_IGMP;
  netif->hwaddr_len = ETHARP_HWADDR_LEN;

  NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, 100000000);

  /* sets link up or down based on current status */
  low_level_init(netif);
  
  return ERR_OK;
}

void
ethernetif_shutdown(struct netif *netif)
{
  shutdown_adapter(netif->state);
}

void
ethernetif_poll(struct netif *netif)
{
  update_adapter(netif->state);

  /* Process the link status change */
  switch (link_adapter(netif->state)) {
    case LINKEVENT_UP: {
      NOTIFY_LINKSTATE(netif,netif_set_link_up);
      break;
    }
    case LINKEVENT_DOWN: {
      NOTIFY_LINKSTATE(netif,netif_set_link_down);
      break;
    }
  }
}

/*-----------------------------------------------------------------------------------*/
/*
 * pktif_update():
 *
 * Needs to be called periodically to get new packets. This could
 * be done inside a thread.
 */
/*-----------------------------------------------------------------------------------*/
void
ethernetif_process_input(void *arg, void *packet, int packet_len)
{
  struct netif *netif = (struct netif*)arg;
  ethernetif_input(netif, packet, packet_len);
}

#endif /* LWIP_ETHERNET */