incubator-nuttx/fs/vfs/fs_dup.c

137 lines
3.4 KiB
C

/****************************************************************************
* fs/vfs/fs_dup.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 <unistd.h>
#include <sched.h>
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <nuttx/fs/fs.h>
#include "inode/inode.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: file_dup
*
* Description:
* Equivalent to the standard dup() function except that it
* accepts a struct file instance instead of a file descriptor.
*
* Returned Value:
* The new file descriptor is returned on success; a negated errno value
* is returned on any failure.
*
****************************************************************************/
int file_dup(FAR struct file *filep, int minfd, int flags)
{
FAR struct file *filep2;
int fd2;
int ret;
#ifdef CONFIG_FDSAN
uint64_t f_tag_fdsan; /* File owner fdsan tag, init to 0 */
#endif
#ifdef CONFIG_FDCHECK
uint8_t f_tag_fdcheck; /* File owner fdcheck tag, init to 0 */
#endif
fd2 = file_allocate(g_root_inode, 0, 0, NULL, minfd, true);
if (fd2 < 0)
{
return fd2;
}
ret = fs_getfilep(fd2, &filep2);
#ifdef CONFIG_FDSAN
f_tag_fdsan = filep2->f_tag_fdsan;
#endif
#ifdef CONFIG_FDCHECK
f_tag_fdcheck = filep2->f_tag_fdcheck;
#endif
DEBUGASSERT(ret >= 0);
ret = file_dup3(filep, filep2, flags);
#ifdef CONFIG_FDSAN
filep2->f_tag_fdsan = f_tag_fdsan;
#endif
#ifdef CONFIG_FDCHECK
filep2->f_tag_fdcheck = f_tag_fdcheck;
#endif
fs_putfilep(filep2);
if (ret >= 0)
{
return fd2;
}
fs_putfilep(filep2);
return ret;
}
/****************************************************************************
* Name: dup
*
* Description:
* Clone a file or socket descriptor to an arbitrary descriptor number
*
****************************************************************************/
int dup(int fd)
{
FAR struct file *filep;
int ret;
/* Get the file structure corresponding to the file descriptor. */
ret = fs_getfilep(fd, &filep);
if (ret < 0)
{
goto err;
}
/* Let file_dup() do the real work */
ret = file_dup(filep, 0, 0);
fs_putfilep(filep);
if (ret < 0)
{
goto err;
}
return ret;
err:
set_errno(-ret);
return ERROR;
}