554310bd78
Change-Id: I2387ab447f0d8ed9429960922a72de35b2730acb Signed-off-by: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>
137 lines
3.6 KiB
C
137 lines
3.6 KiB
C
/****************************************************************************
|
|
* fs/vfs/fs_dup2.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 "inode/inode.h"
|
|
|
|
/****************************************************************************
|
|
* Public Functions
|
|
****************************************************************************/
|
|
|
|
/****************************************************************************
|
|
* Name: file_dup2
|
|
*
|
|
* Description:
|
|
* Assign an inode to a specific files structure. This is the heart of
|
|
* dup2.
|
|
*
|
|
* Equivalent to the non-standard dup2() function except that it
|
|
* accepts struct file instances instead of file descriptors and it does
|
|
* not set the errno variable.
|
|
*
|
|
* Returned Value:
|
|
* Zero (OK) is returned on success; a negated errno value is return on
|
|
* any failure.
|
|
*
|
|
****************************************************************************/
|
|
|
|
int file_dup2(FAR struct file *filep1, FAR struct file *filep2)
|
|
{
|
|
FAR struct inode *inode;
|
|
struct file temp;
|
|
int ret;
|
|
|
|
if (filep1 == NULL || filep1->f_inode == NULL || filep2 == NULL)
|
|
{
|
|
return -EBADF;
|
|
}
|
|
|
|
if (filep1 == filep2)
|
|
{
|
|
return OK;
|
|
}
|
|
|
|
/* Increment the reference count on the contained inode */
|
|
|
|
inode = filep1->f_inode;
|
|
ret = inode_addref(inode);
|
|
if (ret < 0)
|
|
{
|
|
return ret;
|
|
}
|
|
|
|
/* Then clone the file structure */
|
|
|
|
temp.f_oflags = filep1->f_oflags;
|
|
temp.f_pos = filep1->f_pos;
|
|
temp.f_inode = inode;
|
|
temp.f_priv = NULL;
|
|
|
|
/* Call the open method on the file, driver, mountpoint so that it
|
|
* can maintain the correct open counts.
|
|
*/
|
|
|
|
if (inode->u.i_ops)
|
|
{
|
|
#ifndef CONFIG_DISABLE_MOUNTPOINT
|
|
if (INODE_IS_MOUNTPT(inode))
|
|
{
|
|
/* Dup the open file on the in the new file structure */
|
|
|
|
if (inode->u.i_mops->dup)
|
|
{
|
|
ret = inode->u.i_mops->dup(filep1, &temp);
|
|
}
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
/* (Re-)open the pseudo file or device driver */
|
|
|
|
temp.f_priv = filep1->f_priv;
|
|
|
|
if (inode->u.i_ops->open)
|
|
{
|
|
ret = inode->u.i_ops->open(&temp);
|
|
}
|
|
}
|
|
|
|
/* Handle open failures */
|
|
|
|
if (ret < 0)
|
|
{
|
|
inode_release(inode);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
/* If there is already an inode contained in the new file structure,
|
|
* close the file and release the inode.
|
|
*/
|
|
|
|
ret = file_close(filep2);
|
|
DEBUGASSERT(ret == 0);
|
|
|
|
/* Return the file structure */
|
|
|
|
memcpy(filep2, &temp, sizeof(temp));
|
|
return OK;
|
|
}
|