nuttx/libs/libc/netdb/lib_gethostbyaddr.c

/****************************************************************************
 * libs/libc/netdb/lib_gethostbyaddr.c
 *
 *   Copyright (C) 2015 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 <netdb.h>
#include <errno.h>

#include "libc.h"
#include "netdb/lib_netdb.h"

#ifdef CONFIG_NETDB_HOSTFILE

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

/****************************************************************************
 * Name: gethostbyaddr
 *
 * Description:
 *   The gethostbyaddr() function returns a structure of type hostent for
 *   the given host address addr of length len and address type type. Valid
 *   address types are AF_INET and AF_INET6. The host address argument is a
 *   pointer to a struct of a type depending on the address type, for example
 *   a struct in_addr *  for address type AF_INET.
 *
 * Input Parameters:
 *   addr - The address of the host to find.
 *   len - The length of the address
 *   type - The type of the address
 *
 * Returned Value:
 *   Upon successful completion, this function will return a pointer to a
 *   hostent structure if the requested entry was found, and a null pointer
 *   if the end of the database was reached or the requested entry was not
 *   found.
 *
 *   Upon unsuccessful completion, gethostbyaddr() will set h_errno to
 *   indicate the error
 *
 ****************************************************************************/

FAR struct hostent *gethostbyaddr(FAR const void *addr, socklen_t len, int type)
{
  int ret;

  DEBUGASSERT(addr != NULL);
  DEBUGASSERT(type == AF_INET || type == AF_INET6);

  ret = gethostbyaddr_r(addr, len, type, &g_hostent, g_hostbuffer,
                        CONFIG_NETDB_BUFSIZE, &h_errno);
  return ret == 0 ? &g_hostent : NULL;
}

#endif /* CONFIG_NETDB_HOSTFILE */