122 lines
4.1 KiB
C
122 lines
4.1 KiB
C
/****************************************************************************
|
|
* fs/fs_filedup.c
|
|
*
|
|
* Copyright (C) 2007-2009, 2011 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 <sched.h>
|
|
#include <errno.h>
|
|
|
|
#include <nuttx/fs/fs.h>
|
|
|
|
#include "fs_internal.h"
|
|
|
|
#if CONFIG_NFILE_DESCRIPTORS > 0
|
|
|
|
/****************************************************************************
|
|
* Pre-processor Definitions
|
|
****************************************************************************/
|
|
|
|
#define DUP_ISOPEN(fd, list) \
|
|
((unsigned int)fd < CONFIG_NFILE_DESCRIPTORS && \
|
|
list->fl_files[fd].f_inode != NULL)
|
|
|
|
/****************************************************************************
|
|
* Private Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Global Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: file_dup OR dup
|
|
*
|
|
* Description:
|
|
* Clone a file descriptor to an arbitray descriptor number. If socket
|
|
* descriptors are implemented, then this is called by dup() for the case
|
|
* of file descriptors. If socket descriptors are not implemented, then
|
|
* this function IS dup().
|
|
*
|
|
****************************************************************************/
|
|
|
|
int file_dup(int fildes, int minfd)
|
|
{
|
|
FAR struct filelist *list;
|
|
int fildes2;
|
|
|
|
/* Get the thread-specific file list */
|
|
|
|
list = sched_getfiles();
|
|
if (!list)
|
|
{
|
|
set_errno(EMFILE);
|
|
return ERROR;
|
|
}
|
|
|
|
/* Verify that fildes is a valid, open file descriptor */
|
|
|
|
if (!DUP_ISOPEN(fildes, list))
|
|
{
|
|
set_errno(EBADF);
|
|
return ERROR;
|
|
}
|
|
|
|
/* Increment the reference count on the contained inode */
|
|
|
|
inode_addref(list->fl_files[fildes].f_inode);
|
|
|
|
/* Then allocate a new file descriptor for the inode */
|
|
|
|
fildes2 = files_allocate(list->fl_files[fildes].f_inode,
|
|
list->fl_files[fildes].f_oflags,
|
|
list->fl_files[fildes].f_pos,
|
|
minfd);
|
|
if (fildes2 < 0)
|
|
{
|
|
set_errno(EMFILE);
|
|
inode_release(list->fl_files[fildes].f_inode);
|
|
return ERROR;
|
|
}
|
|
|
|
return fildes2;
|
|
}
|
|
|
|
#endif /* CONFIG_NFILE_DESCRIPTORS > 0 */
|
|
|