/****************************************************************************
 * net/socket/shutdown.c
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

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

#include <nuttx/config.h>

#include <errno.h>
#include <sys/socket.h>

#include <nuttx/net/net.h>

#include "socket/socket.h"

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

/****************************************************************************
 * Name: psock_shutdown
 *
 * Description:
 *   The shutdown() function will cause all or part of a full-duplex
 *   connection on the socket associated with the file descriptor socket to
 *   be shut down.
 *
 *   The shutdown() function disables subsequent send and/or receive
 *   operations on a socket, depending on the value of the how argument.
 *
 * Input Parameters:
 *   sockfd - Specifies the file descriptor of the socket.
 *   how    - Specifies the type of shutdown. The values are as follows:
 *
 *     SHUT_RD   - Disables further receive operations.
 *     SHUT_WR   - Disables further send operations.
 *     SHUT_RDWR - Disables further send and receive operations.
 *
 * Returned Value:
 *   On success, returns the number of characters sent.  On any failure, a
 *   negated errno value is returned.  One of:
 *
 *     EINVAL     - The how argument is invalid.
 *     ENOTCONN   - The socket is not connected.
 *     ENOTSOCK   - The socket argument does not refer to a socket.
 *     ENOBUFS    - Insufficient resources were available in the system to
 *                  perform the operation.
 *     EOPNOTSUPP - The operation is not supported for this socket's protocol
 *
 ****************************************************************************/

int psock_shutdown(FAR struct socket *psock, int how)
{
  /* Verify that the psock corresponds to valid, allocated socket */

  if (psock == NULL || psock->s_conn == NULL)
    {
      return -EBADF;
    }

  /* Let the address family's shutdown() method handle the operation */

  if (psock->s_sockif && psock->s_sockif->si_shutdown)
    {
      return psock->s_sockif->si_shutdown(psock, how);
    }

  return -EOPNOTSUPP;
}

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

/****************************************************************************
 * Name: shutdown
 *
 * Description:
 *   The shutdown() function will cause all or part of a full-duplex
 *   connection on the socket associated with the file descriptor socket to
 *   be shut down.
 *
 *   The shutdown() function disables subsequent send and/or receive
 *   operations on a socket, depending on the value of the how argument.
 *
 * Input Parameters:
 *   sockfd - Specifies the file descriptor of the socket.
 *   how    - Specifies the type of shutdown. The values are as follows:
 *
 *     SHUT_RD   - Disables further receive operations.
 *     SHUT_WR   - Disables further send operations.
 *     SHUT_RDWR - Disables further send and receive operations.
 *
 * Returned Value:
 *   Upon successful completion, shutdown() will return 0; otherwise, -1 will
 *   be returned and errno set to indicate the error.
 *
 *     EBADF      - The socket argument is not a valid file descriptor.
 *     EINVAL     - The how argument is invalid.
 *     ENOTCONN   - The socket is not connected.
 *     ENOTSOCK   - The socket argument does not refer to a socket.
 *     ENOBUFS    - Insufficient resources were available in the system to
 *                  perform the operation.
 *     EOPNOTSUPP - The operation is not supported for this socket's protocol
 *
 ****************************************************************************/

int shutdown(int sockfd, int how)
{
  FAR struct socket *psock;
  int ret;

  /* Get the underlying socket structure */

  ret = sockfd_socket(sockfd, &psock);

  /* Then let psock_shutdown() do all of the work */

  if (ret == OK)
    {
      ret = psock_shutdown(psock, how);
    }

  if (ret < 0)
    {
      set_errno(-ret);
      ret = ERROR;
    }

  return ret;
}