/****************************************************************************
 * net/netdev/netdev_ifconf.c
 *
 *   Copyright (C) 2017 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *
 * 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 NuttX 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 COPYRIGHT HOLDERS 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
 * COPYRIGHT OWNER 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.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <string.h>
#include <assert.h>
#include <errno.h>

#include <net/if.h>
#include <nuttx/net/netdev.h>

#include "inet/inet.h"
#include "utils/utils.h"
#include "netdev/netdev.h"

/****************************************************************************
 * Private Types
 ****************************************************************************/

/* The form of information passed with netdev_foreach() callback */

#ifdef CONFIG_NET_IPv4
struct ifconf_ipv4_info_s
{
  size_t bufsize;
  FAR struct ifconf *ifc;
};
#endif

#ifdef CONFIG_NET_IPv6
struct ifconf_ipv6_info_s
{
  size_t bufsize;
  FAR struct lifconf *lifc;
};
#endif

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: ifconf_ipv4_callback
 *
 * Description:
 *   Callback from netdev_foreach() that does the real implementation of
 *   netdev_ipv4_ifconf().
 *
 * Parameters:
 *   dev - The network device for this callback.
 *   arg - User callback argument
 *
 * Returned Value:
 *   Zero is returned on success; a negated errno value is returned on any
 *   failure.
 *
 ****************************************************************************/

#ifdef CONFIG_NET_IPv4
static int ifconf_ipv4_callback(FAR struct net_driver_s *dev, FAR void *arg)
{
  FAR struct ifconf_ipv4_info_s *info = (FAR struct ifconf_ipv4_info_s *)arg;
  FAR struct ifconf *ifc;

  DEBUGASSERT(dev != NULL && info != NULL && info->ifc != NULL);
  ifc = info->ifc;

  /* Check if this adaptor has an IPv4 address assigned and is in the UP
   * state.
   */

  if (!net_ipv4addr_cmp(dev->d_ipaddr, INADDR_ANY) &&
      (dev->d_flags & IFF_UP) != 0)
    {
      /* Check if we would exceed the buffer space provided by the caller.
       * NOTE: A common usage model is:
       *
       * 1) Provide no buffer with the first SIOCGIFCONF command.  In this
       *    case, only the size of the buffer needed for all of IPv4
       *    capable interface information is returned.
       * 2) Allocate a buffer of that size
       * 3) Then use the allocated buffer to receive all of the IPv4
       *    interface information on the second SIOCGIFCONF command.
       *
       * CAUTION: The number of IPv6 capable interface may change between
       * calls.  It is the callers responsibility to behave sanely in such
       * cases.
       */

       if (ifc->ifc_len + sizeof(struct ifreq) <= info->bufsize)
         {
           FAR struct ifreq *req =
             (FAR struct ifreq *)&ifc->ifc_buf[ifc->ifc_len];
           FAR struct sockaddr_in *inaddr =
             (FAR struct sockaddr_in *)&req->ifr_addr;

           /* There is space for information about another adaptor.  Within
            * each ifreq structure, ifr_name will receive the interface name
            * and ifr_addr the address.  The actual number of bytes
            * transferred is returned in ifc_len.
            */

           strncpy(req->ifr_name, dev->d_ifname, IFNAMSIZ);

           inaddr->sin_family = AF_INET;
           inaddr->sin_port   = 0;
           net_ipv4addr_copy(inaddr->sin_addr.s_addr, dev->d_ipaddr);
         }

       /* Increment the size of the buffer in any event */

       ifc->ifc_len += sizeof(struct ifreq);
    }

  return 0;
}
#endif

/****************************************************************************
 * Name: ifconf_ipv6_callback
 *
 * Description:
 *   Callback from netdev_foreach() that does the real implementation of
 *   netdev_ipv6_ifconf().
 *
 * Parameters:
 *   dev - The network device for this callback.
 *   arg - User callback argument
 *
 * Returned Value:
 *   Zero is returned on success; a negated errno value is returned on any
 *   failure.
 *
 ****************************************************************************/

#ifdef CONFIG_NET_IPv6
static int ifconf_ipv6_callback(FAR struct net_driver_s *dev, FAR void *arg)
{
  FAR struct ifconf_ipv6_info_s *info = (FAR struct ifconf_ipv6_info_s *)arg;
  FAR struct lifconf *lifc;

  DEBUGASSERT(dev != NULL && info != NULL && info->lifc != NULL);
  lifc = info->lifc;

  /* Check if this adaptor has an IPv6 address assigned and is in the UP
   * state.
   */

  if (!net_ipv6addr_cmp(dev->d_ipv6addr, g_ipv6_allzeroaddr) &&
      (dev->d_flags & IFF_UP) != 0)
    {
      /* Check if we would exceed the buffer space provided by the caller.
       * NOTE: A common usage model is:
       *
       * 1) Provide no buffer with the first SIOCGLIFCONF command.  In this
       *    case, only the size of the buffer needed for all of IPv6
       *    capable interface information is returned.
       * 2) Allocate a buffer of that size
       * 3) Then use the allocated buffer to receive all of the IPv6
       *    interface information on the second SIOCGLIFCONF command.
       *
       * CAUTION: The number of IPv6 capable interface may change between
       * calls.  It is the callers responsibility to behave sanely in such
       * cases.
       */

       if (lifc->lifc_len + sizeof(struct lifreq) <= info->bufsize)
         {
           FAR struct lifreq *req =
             (FAR struct lifreq *)&lifc->lifc_buf[lifc->lifc_len];
           FAR struct sockaddr_in6 *inaddr =
             (FAR struct sockaddr_in6 *)&req->lifr_addr;

           /* There is space for information about another adaptor.  Within
            * each ifreq structure, lifr_name will receive the interface
            * name and lifr_addr the address.  The actual number of bytes
            * transferred is returned in lifc_len.
            */

           strncpy(req->lifr_name, dev->d_ifname, IFNAMSIZ);

           inaddr->sin6_family = AF_INET6;
           inaddr->sin6_port   = 0;
           net_ipv6addr_copy(inaddr->sin6_addr.s6_addr16, dev->d_ipv6addr);
         }

       /* Increment the size of the buffer in any event */

       lifc->lifc_len += sizeof(struct lifreq);
    }

  return 0;
}
#endif

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: netdev_ipv4_ifconf
 *
 * Description:
 *   Return the IPv4 configuration of each network adaptor that (1) has
 *   and IPv4 address assigned and (2) is in the UP state
 *
 * Parameters:
 *   ifc - A reference to the instance of struct ifconf in which to return
 *         the information.
 *
 * Returned Value:
 *   Zero is returned on success; a negated errno value is returned on any
 *   failure.
 *
 * Assumptions:
 *  The nework is locked
 *
 ****************************************************************************/

#ifdef CONFIG_NET_IPv4
int netdev_ipv4_ifconf(FAR struct ifconf *ifc)
{
  struct ifconf_ipv4_info_s info;

  info.bufsize = ifc->ifc_len;
  info.ifc     = ifc;
  ifc->ifc_len = 0;

  return netdev_foreach(ifconf_ipv4_callback, (FAR void *)&info);
}
#endif

/****************************************************************************
 * Name: netdev_ipv6_ifconf
 *
 * Description:
 *   Return the IPv6 configuration of each network adaptor that (1) has
 *   and IPv6 address assigned and (2) is in the UP state.
 *
 * Parameters:
 *   lifc - A reference to the instance of struct lifconf in which to return
 *          the information.
 *
 * Returned Value:
 *   Zero is returned on success; a negated errno value is returned on any
 *   failure.
 *
 * Assumptions:
 *  The nework is locked
 *
 ****************************************************************************/

#ifdef CONFIG_NET_IPv6
int netdev_ipv6_ifconf(FAR struct lifconf *lifc)
{
  struct ifconf_ipv6_info_s info;

  info.bufsize   = lifc->lifc_len;
  info.lifc      = lifc;
  lifc->lifc_len = 0;

  return netdev_foreach(ifconf_ipv6_callback, (FAR void *)&info);
}
#endif