incubator-nuttx/fs/vfs/fs_dup.c

108 lines
3.5 KiB
C

/****************************************************************************
* fs/vfs/fs_dup.c
*
* Copyright (C) 2007-2009, 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 <unistd.h>
#include <sched.h>
#include <errno.h>
#include <nuttx/fs/fs.h>
#include "inode/inode.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: dup
*
* Description:
* Clone a file or socket descriptor to an arbitrary descriptor number
*
****************************************************************************/
int dup(int fd)
{
int ret = OK;
/* Check the range of the descriptor to see if we got a file or a socket
* descriptor.
*/
if ((unsigned int)fd < CONFIG_NFILE_DESCRIPTORS)
{
/* Its a valid file descriptor.. dup the file descriptor using any
* other file descriptor. fd_dupfd() sets the errno value in the
* event of any failures.
*/
ret = fs_dupfd(fd, 0);
}
else
{
/* Not a valid file descriptor. Did we get a valid socket descriptor? */
#ifdef CONFIG_NET
if ((unsigned int)fd < (CONFIG_NFILE_DESCRIPTORS + CONFIG_NSOCKET_DESCRIPTORS))
{
/* Yes.. dup the socket descriptor. The errno value is not set. */
ret = net_dup(fd, CONFIG_NFILE_DESCRIPTORS);
}
else
#endif
{
/* No.. then it is a bad descriptor number */
ret = -EBADF;
}
/* Set the errno value on failures */
if (ret < 0)
{
set_errno(-ret);
ret = ERROR;
}
}
return ret;
}