}
  }
  /* enable getnext traversal on filled table */
  iprtetable.maxlength = 1;
}

/**
 * Removes ipRouteTable indexes (.ipRouteDest)
 * from index tree.
 *
 * @param dflt non-zero for the default rte, zero for network rte
 * @param ni points to network interface for this rte or NULL
 *   for default route to be removed.
 */
void snmp_delete_iprteidx_tree(u8_t dflt, struct netif *ni)
{
  u8_t delete = 0;
  struct ip_addr dst;

  if (dflt != 0)
  {
    /* the default route 0.0.0.0 */
    dst.addr = 0;
    delete = 1;
  }
  else
  {
    /* route to the network address */
    dst.addr = ntohl(ni->ip_addr.addr & ni->netmask.addr);
    /* exclude 0.0.0.0 network (reserved for default rte) */
    if (dst.addr != 0) delete = 1;
  }
  if (delete)
  {
    struct mib_list_rootnode *iprte_rn, *next, *del_rn[4];
    struct mib_list_node *iprte_n, *del_n[4];
    s32_t iprteidx[4];
    u8_t fc, level, del_cnt;

    snmp_iptooid(&dst, &iprteidx[0]);
    /* mark nodes for deletion */
    level = 0;
    del_cnt = 0;
    iprte_rn = &iprtetree_root;
    while ((level < 4) && (iprte_rn != NULL))
    {
      fc = snmp_mib_node_find(iprte_rn, iprteidx[level], &iprte_n);
      if (fc == 0)
      {
        /* iprteidx[level] does not exist */
        del_cnt = 0;
        iprte_rn = NULL;
      }
      else if (fc == 1)
      {
        del_rn[del_cnt] = iprte_rn;
        del_n[del_cnt] = iprte_n;
        del_cnt++;
        iprte_rn = (struct mib_list_rootnode*)(iprte_n->nptr);
      }
      else if (fc == 2)
      {
        /* reset delete (2 or more childs) */
        del_cnt = 0;
        iprte_rn = (struct mib_list_rootnode*)(iprte_n->nptr);
      }
      level++;
    }
    /* delete marked index nodes */
    while (del_cnt > 0)
    {
      del_cnt--;

      iprte_rn = del_rn[del_cnt];
      iprte_n = del_n[del_cnt];

      next = snmp_mib_node_delete(iprte_rn, iprte_n);
      if (next != NULL)
      {
        LWIP_ASSERT("next_count == 0",next->count == 0);
        snmp_mib_lrn_free(next);
      }
    }
  }
  /* disable getnext traversal on empty table */
  if (iprtetree_root.count == 0) iprtetable.maxlength = 0;
}


void snmp_inc_icmpinmsgs(void)
{
  icmpinmsgs++;
}

void snmp_inc_icmpinerrors(void)
{
  icmpinerrors++;
}

void snmp_inc_icmpindestunreachs(void)
{
  icmpindestunreachs++;
}

void snmp_inc_icmpintimeexcds(void)
{
  icmpintimeexcds++;
}

void snmp_inc_icmpinparmprobs(void)
{
  icmpinparmprobs++;
}

void snmp_inc_icmpinsrcquenchs(void)
{
  icmpinsrcquenchs++;
}

void snmp_inc_icmpinredirects(void)
{
  icmpinredirects++;
}

void snmp_inc_icmpinechos(void)
{
  icmpinechos++;
}

void snmp_inc_icmpinechoreps(void)
{
  icmpinechoreps++;
}

void snmp_inc_icmpintimestamps(void)
{
  icmpintimestamps++;
}

void snmp_inc_icmpintimestampreps(void)
{
  icmpintimestampreps++;
}

void snmp_inc_icmpinaddrmasks(void)
{
  icmpinaddrmasks++;
}

void snmp_inc_icmpinaddrmaskreps(void)
{
  icmpinaddrmaskreps++;
}

void snmp_inc_icmpoutmsgs(void)
{
  icmpoutmsgs++;
}

void snmp_inc_icmpouterrors(void)
{
  icmpouterrors++;
}

void snmp_inc_icmpoutdestunreachs(void)
{
  icmpoutdestunreachs++;
}

void snmp_inc_icmpouttimeexcds(void)
{
  icmpouttimeexcds++;
}

void snmp_inc_icmpoutparmprobs(void)
{
  icmpoutparmprobs++;
}

void snmp_inc_icmpoutsrcquenchs(void)
{
  icmpoutsrcquenchs++;
}

void snmp_inc_icmpoutredirects(void)
{
  icmpoutredirects++;
}

void snmp_inc_icmpoutechos(void)
{
  icmpoutechos++;
}

void snmp_inc_icmpoutechoreps(void)
{
  icmpoutechoreps++;
}

void snmp_inc_icmpouttimestamps(void)
{
  icmpouttimestamps++;
}

void snmp_inc_icmpouttimestampreps(void)
{
  icmpouttimestampreps++;
}

void snmp_inc_icmpoutaddrmasks(void)
{
  icmpoutaddrmasks++;
}

void snmp_inc_icmpoutaddrmaskreps(void)
{
  icmpoutaddrmaskreps++;
}

void snmp_inc_tcpactiveopens(void)
{
  tcpactiveopens++;
}

void snmp_inc_tcppassiveopens(void)
{
  tcppassiveopens++;
}

void snmp_inc_tcpattemptfails(void)
{
  tcpattemptfails++;
}

void snmp_inc_tcpestabresets(void)
{
  tcpestabresets++;
}

void snmp_inc_tcpinsegs(void)
{
  tcpinsegs++;
}

void snmp_inc_tcpoutsegs(void)
{
  tcpoutsegs++;
}

void snmp_inc_tcpretranssegs(void)
{
  tcpretranssegs++;
}

void snmp_inc_tcpinerrs(void)
{
  tcpinerrs++;
}

void snmp_inc_tcpoutrsts(void)
{
  tcpoutrsts++;
}

void snmp_inc_udpindatagrams(void)
{
  udpindatagrams++;
}

void snmp_inc_udpnoports(void)
{
  udpnoports++;
}

void snmp_inc_udpinerrors(void)
{
  udpinerrors++;
}

void snmp_inc_udpoutdatagrams(void)
{
  udpoutdatagrams++;
}

/**
 * Inserts udpTable indexes (.udpLocalAddress.udpLocalPort)
 * into index tree.
 */
void snmp_insert_udpidx_tree(struct udp_pcb *pcb)
{
  struct mib_list_rootnode *udp_rn;
  struct mib_list_node *udp_node;
  struct ip_addr ip;
  s32_t udpidx[5];
  u8_t level;

  LWIP_ASSERT("pcb != NULL", pcb != NULL);
  ip.addr = ntohl(pcb->local_ip.addr);
  snmp_iptooid(&ip, &udpidx[0]);
  udpidx[4] = pcb->local_port;

  udp_rn = &udp_root;
  for (level = 0; level < 5; level++)
  {
    udp_node = NULL;
    snmp_mib_node_insert(udp_rn, udpidx[level], &udp_node);
    if ((level != 4) && (udp_node != NULL))
    {
      if (udp_node->nptr == NULL)
      {
        udp_rn = snmp_mib_lrn_alloc();
        udp_node->nptr = (struct mib_node*)udp_rn;
        if (udp_rn != NULL)
        {
          if (level == 3)
          {
            udp_rn->get_object_def = udpentry_get_object_def;
            udp_rn->get_value = udpentry_get_value;
            udp_rn->set_test = noleafs_set_test;
            udp_rn->set_value = noleafs_set_value;
          }
        }
        else
        {
          /* udp_rn == NULL, malloc failure */
          LWIP_DEBUGF(SNMP_MIB_DEBUG,("snmp_insert_udpidx_tree() insert failed, mem full"));
          break;
        }
      }
      else
      {
        udp_rn = (struct mib_list_rootnode*)udp_node->nptr;
      }
    }
  }
  udptable.maxlength = 1;
}

/**
 * Removes udpTable indexes (.udpLocalAddress.udpLocalPort)
 * from index tree.
 */
void snmp_delete_udpidx_tree(struct udp_pcb *pcb)
{
  struct mib_list_rootnode *udp_rn, *next, *del_rn[5];
  struct mib_list_node *udp_n, *del_n[5];
  struct ip_addr ip;
  s32_t udpidx[5];
  u8_t bindings, fc, level, del_cnt;

  LWIP_ASSERT("pcb != NULL", pcb != NULL);
  ip.addr = ntohl(pcb->local_ip.addr);
  snmp_iptooid(&ip, &udpidx[0]);
  udpidx[4] = pcb->local_port;

  /* count PCBs for a given binding
     (e.g. when reusing ports or for temp output PCBs) */
  bindings = 0;
  pcb = udp_pcbs;
  while ((pcb != NULL))
  {
    if ((pcb->local_ip.addr == ip.addr) &&
        (pcb->local_port == udpidx[4]))
    {
      bindings++;
    }
    pcb = pcb->next;
  }
  if (bindings == 1)
  {
    /* selectively remove */
    /* mark nodes for deletion */
    level = 0;
    del_cnt = 0;
    udp_rn = &udp_root;
    while ((level < 5) && (udp_rn != NULL))
    {
      fc = snmp_mib_node_find(udp_rn, udpidx[level], &udp_n);
      if (fc == 0)
      {
        /* udpidx[level] does not exist */
        del_cnt = 0;
        udp_rn = NULL;
      }
      else if (fc == 1)
      {
        del_rn[del_cnt] = udp_rn;
        del_n[del_cnt] = udp_n;
        del_cnt++;
        udp_rn = (struct mib_list_rootnode*)(udp_n->nptr);
      }
      else if (fc == 2)
      {
        /* reset delete (2 or more childs) */
        del_cnt = 0;
        udp_rn = (struct mib_list_rootnode*)(udp_n->nptr);
      }
      level++;
    }
    /* delete marked index nodes */
    while (del_cnt > 0)
    {
      del_cnt--;

      udp_rn = del_rn[del_cnt];
      udp_n = del_n[del_cnt];

      next = snmp_mib_node_delete(udp_rn, udp_n);
      if (next != NULL)
      {
        LWIP_ASSERT("next_count == 0",next->count == 0);
        snmp_mib_lrn_free(next);
      }
    }
  }
  /* disable getnext traversal on empty table */
  if (udp_root.count == 0) udptable.maxlength = 0;
}


void snmp_inc_snmpinpkts(void)
{
  snmpinpkts++;
}

void snmp_inc_snmpoutpkts(void)
{
  snmpoutpkts++;
}

void snmp_inc_snmpinbadversions(void)
{
  snmpinbadversions++;
}

void snmp_inc_snmpinbadcommunitynames(void)
{
  snmpinbadcommunitynames++;
}

void snmp_inc_snmpinbadcommunityuses(void)
{
  snmpinbadcommunityuses++;
}

void snmp_inc_snmpinasnparseerrs(void)
{
  snmpinasnparseerrs++;
}

void snmp_inc_snmpintoobigs(void)
{
  snmpintoobigs++;
}

void snmp_inc_snmpinnosuchnames(void)
{
  snmpinnosuchnames++;
}

void snmp_inc_snmpinbadvalues(void)
{
  snmpinbadvalues++;
}

void snmp_inc_snmpinreadonlys(void)
{
  snmpinreadonlys++;
}

void snmp_inc_snmpingenerrs(void)
{
  snmpingenerrs++;
}

void snmp_add_snmpintotalreqvars(u8_t value)
{
  snmpintotalreqvars += value;
}

void snmp_add_snmpintotalsetvars(u8_t value)
{
  snmpintotalsetvars += value;
}

void snmp_inc_snmpingetrequests(void)
{
  snmpingetrequests++;
}

void snmp_inc_snmpingetnexts(void)
{
  snmpingetnexts++;
}

void snmp_inc_snmpinsetrequests(void)
{
  snmpinsetrequests++;
}

void snmp_inc_snmpingetresponses(void)