px4-firmware/nuttx/fs/fs_statfs.c

166 lines
4.9 KiB
C

/****************************************************************************
* fs/fs_statfs.c
*
* Copyright (C) 2007-2009, 2012 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/statfs.h>
#include <string.h>
#include <limits.h>
#include <sched.h>
#include <errno.h>
#include "fs_internal.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: statpsuedo
****************************************************************************/
static inline int statpsuedofs(FAR struct inode *inode, FAR struct statfs *buf)
{
memset(buf, 0, sizeof(struct statfs));
buf->f_type = PROC_SUPER_MAGIC;
buf->f_namelen = NAME_MAX;
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: stat
*
* Return: Zero on success; -1 on failure with errno set:
*
* EACCES Search permission is denied for one of the directories in the
* path prefix of path.
* EFAULT Bad address.
* ENOENT A component of the path path does not exist, or the path is an
* empty string.
* ENOMEM Out of memory
* ENOTDIR A component of the path is not a directory.
* ENOSYS The file system does not support this call.
*
****************************************************************************/
int statfs(FAR const char *path, FAR struct statfs *buf)
{
FAR struct inode *inode;
FAR const char *relpath = NULL;
int ret = OK;
/* Sanity checks */
if (!path || !buf)
{
ret = EFAULT;
goto errout;
}
if (!path[0])
{
ret = ENOENT;
goto errout;
}
/* Get an inode for this file */
inode = inode_find(path, &relpath);
if (!inode)
{
/* This name does not refer to a psudeo-inode and there is no
* mountpoint that includes in this path.
*/
ret = ENOENT;
goto errout;
}
/* The way we handle the statfs depends on the type of inode that we
* are dealing with.
*/
#ifndef CONFIG_DISABLE_MOUNTPOINT
if (INODE_IS_MOUNTPT(inode))
{
/* The node is a file system mointpoint. Verify that the mountpoint
* supports the statfs() method
*/
if (inode->u.i_mops && inode->u.i_mops->statfs)
{
/* Perform the statfs() operation */
ret = inode->u.i_mops->statfs(inode, buf);
}
}
else
#endif
{
/* The node is part of the root psuedo file system */
ret = statpsuedofs(inode, buf);
}
/* Check if the statfs operation was successful */
if (ret < 0)
{
ret = -ret;
goto errout_with_inode;
}
/* Successfully statfs'ed the file */
inode_release(inode);
return OK;
/* Failure conditions always set the errno appropriately */
errout_with_inode:
inode_release(inode);
errout:
set_errno(ret);
return ERROR;
}