nuttx-apps/netutils/netlib/netlib_getessid.c

/****************************************************************************
 * netutils/netlib/netlib_getessid.c
 *
 *   Copyright (C) 2017-2018 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 <sys/socket.h>
#include <sys/ioctl.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>

#include <netinet/in.h>
#include <net/if.h>

#include <nuttx/wireless/wireless.h>

#include "netutils/netlib.h"

#ifdef CONFIG_NET

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

/****************************************************************************
 * Name: netlib_getessid
 *
 * Description:
 *   Get the wireless access point ESSID
 *
 * Parameters:
 *   ifname   The name of the interface to use
 *   essid    Location to store the returned ESSID, size must be
 *            IW_ESSID_MAX_SIZE + 1 or larger
 *   idlen    size of memory set asdie for the ESSID.
 *
 * Return:
 *   0 on success; -1 on failure (errno may not be set)
 *
 ****************************************************************************/

int netlib_getessid(FAR const char *ifname, FAR char *essid, size_t idlen)
{
  int ret = ERROR;

  if (ifname != NULL && essid != NULL && idlen > IW_ESSID_MAX_SIZE)
    {
      /* Get a socket (only so that we get access to the INET subsystem) */

      int sockfd = socket(NETLIB_SOCK_FAMILY,
                          NETLIB_SOCK_TYPE, NETLIB_SOCK_PROTOCOL);
      if (sockfd >= 0)
        {
          struct iwreq req;

          /* Put the driver name into the request */

          memset(&req, 0, sizeof(struct iwreq));
          strncpy(req.ifr_name, ifname, IFNAMSIZ);

          /* Put pointer to receive the ESSID into the request */

          req.u.essid.pointer = (FAR void *)essid;

          /* Perform the ioctl to get the ESSID */

          ret = ioctl(sockfd, SIOCGIWESSID, (unsigned long)&req);
          close(sockfd);
        }
    }

  return ret;
}

#endif /* CONFIG_NET */