incubator-nuttx/net/socket/net_dupsd2.c

113 lines
3.7 KiB
C

/****************************************************************************
* net/socket/net_dupsd2.c
*
* Copyright (C) 2009, 2011, 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 <sys/socket.h>
#include <sched.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/net/net.h>
#include "socket/socket.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: net_dupsd2
*
* Description:
* Clone a socket descriptor to an arbitray descriptor number. If file
* descriptors are implemented, then this is called by dup2() for the case
* of socket file descriptors. If file descriptors are not implemented,
* then this function IS dup2().
*
* Returned Value:
* On success, returns the number of characters sent. On any error,
* a negated errno value is returned:.
*
****************************************************************************/
int net_dupsd2(int sockfd1, int sockfd2)
{
FAR struct socket *psock1;
FAR struct socket *psock2;
int ret;
/* Lock the scheduler throughout the following */
sched_lock();
/* Get the socket structures underly both descriptors */
psock1 = sockfd_socket(sockfd1);
psock2 = sockfd_socket(sockfd2);
/* Verify that the sockfd1 and sockfd2 both refer to valid socket
* descriptors and that sockfd2 corresponds to an allocated socket
*/
if (psock1 == NULL || psock2 == NULL || psock1->s_crefs <= 0)
{
ret = -EBADF;
goto errout;
}
/* If sockfd2 also valid, allocated socket, then we will have to
* close it!
*/
if (psock2->s_crefs > 0)
{
net_close(sockfd2);
}
/* Duplicate the socket state */
ret = net_clone(psock1, psock2);
errout:
sched_unlock();
return ret;
}