FreeRTOS/Common/ethernet/uIP/uip-1.0/uip/uip-neighbor.c

   1 /*
   2  * Copyright (c) 2006, Swedish Institute of Computer Science.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the Institute nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * This file is part of the uIP TCP/IP stack
  30  *
  31  * $Id: uip-neighbor.c,v 1.2 2006/06/12 08:00:30 adam Exp $
  32  */
  33
  34 /**
  35  * \file
  36  *         Database of link-local neighbors, used by IPv6 code and
  37  *         to be used by a future ARP code rewrite.
  38  * \author
  39  *         Adam Dunkels <adam@sics.se>
  40  */
  41
  42 #include "uip-neighbor.h"
  43
  44 #include <string.h>
  45 #include <stdio.h>
  46
  47 #define MAX_TIME 128
  48
  49 #ifdef UIP_NEIGHBOR_CONF_ENTRIES
  50 #define ENTRIES UIP_NEIGHBOR_CONF_ENTRIES
  51 #else /* UIP_NEIGHBOR_CONF_ENTRIES */
  52 #define ENTRIES 8
  53 #endif /* UIP_NEIGHBOR_CONF_ENTRIES */
  54
  55 struct neighbor_entry {
  56   uip_ipaddr_t ipaddr;
  57   struct uip_neighbor_addr addr;
  58   u8_t time;
  59 };
  60 static struct neighbor_entry entries[ENTRIES];
  61
  62 /*---------------------------------------------------------------------------*/
  63 void
  64 uip_neighbor_init(void)
  65 {
  66   int i;
  67
  68   for(i = 0; i < ENTRIES; ++i) {
  69     entries[i].time = MAX_TIME;
  70   }
  71 }
  72 /*---------------------------------------------------------------------------*/
  73 void
  74 uip_neighbor_periodic(void)
  75 {
  76   int i;
  77
  78   for(i = 0; i < ENTRIES; ++i) {
  79     if(entries[i].time < MAX_TIME) {
  80       entries[i].time++;
  81     }
  82   }
  83 }
  84 /*---------------------------------------------------------------------------*/
  85 void
  86 uip_neighbor_add(uip_ipaddr_t ipaddr, struct uip_neighbor_addr *addr)
  87 {
  88   int i, oldest;
  89   u8_t oldest_time;
  90
  91   printf("Adding neighbor with link address %02x:%02x:%02x:%02x:%02x:%02x\n",
  92          addr->addr.addr[0], addr->addr.addr[1], addr->addr.addr[2], addr->addr.addr[3],
  93          addr->addr.addr[4], addr->addr.addr[5]);
  94
  95   /* Find the first unused entry or the oldest used entry. */
  96   oldest_time = 0;
  97   oldest = 0;
  98   for(i = 0; i < ENTRIES; ++i) {
  99     if(entries[i].time == MAX_TIME) {
 100       oldest = i;
 101       break;
 102     }
 103     if(uip_ipaddr_cmp(entries[i].ipaddr, addr)) {
 104       oldest = i;
 105       break;
 106     }
 107     if(entries[i].time > oldest_time) {
 108       oldest = i;
 109       oldest_time = entries[i].time;
 110     }
 111   }
 112
 113   /* Use the oldest or first free entry (either pointed to by the
 114      "oldest" variable). */
 115   entries[oldest].time = 0;
 116   uip_ipaddr_copy(entries[oldest].ipaddr, ipaddr);
 117   memcpy(&entries[oldest].addr, addr, sizeof(struct uip_neighbor_addr));
 118 }
 119 /*---------------------------------------------------------------------------*/
 120 static struct neighbor_entry *
 121 find_entry(uip_ipaddr_t ipaddr)
 122 {
 123   int i;
 124
 125   for(i = 0; i < ENTRIES; ++i) {
 126     if(uip_ipaddr_cmp(entries[i].ipaddr, ipaddr)) {
 127       return &entries[i];
 128     }
 129   }
 130   return NULL;
 131 }
 132 /*---------------------------------------------------------------------------*/
 133 void
 134 uip_neighbor_update(uip_ipaddr_t ipaddr)
 135 {
 136   struct neighbor_entry *e;
 137
 138   e = find_entry(ipaddr);
 139   if(e != NULL) {
 140     e->time = 0;
 141   }
 142 }
 143 /*---------------------------------------------------------------------------*/
 144 struct uip_neighbor_addr *
 145 uip_neighbor_lookup(uip_ipaddr_t ipaddr)
 146 {
 147   struct neighbor_entry *e;
 148
 149   e = find_entry(ipaddr);
 150   if(e != NULL) {
 151     /*    printf("Lookup neighbor with link address %02x:%02x:%02x:%02x:%02x:%02x\n",
 152            e->addr.addr.addr[0], e->addr.addr.addr[1], e->addr.addr.addr[2], e->addr.addr.addr[3],
 153            e->addr.addr.addr[4], e->addr.addr.addr[5]);*/
 154
 155     return &e->addr;
 156   }
 157   return NULL;
 158 }
 159 /*---------------------------------------------------------------------------*/