incubator-nuttx/fs/vfs/fs_statfs.c

164 lines
4.3 KiB
C

/****************************************************************************
* fs/vfs/fs_statfs.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 <sys/statfs.h>
#include <string.h>
#include <limits.h>
#include <sched.h>
#include <errno.h>
#include "inode/inode.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: statpseudo
****************************************************************************/
static int statpseudofs(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: statfs
*
* Returned Value:
* 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)
{
struct inode_search_s desc;
FAR struct inode *inode;
int ret = OK;
/* Sanity checks */
if (path == NULL || buf == NULL)
{
ret = EFAULT;
goto errout;
}
if (*path == '\0')
{
ret = ENOENT;
goto errout;
}
/* Get an inode for this file */
SETUP_SEARCH(&desc, path, false);
ret = inode_find(&desc);
if (ret < 0)
{
/* This name does not refer to a psudeo-inode and there is no
* mountpoint that includes in this path.
*/
ret = -ret;
goto errout_with_search;
}
/* Get the search results */
inode = desc.node;
DEBUGASSERT(inode != NULL);
/* 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 pseudo file system */
ret = statpseudofs(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);
RELEASE_SEARCH(&desc);
return OK;
/* Failure conditions always set the errno appropriately */
errout_with_inode:
inode_release(inode);
errout_with_search:
RELEASE_SEARCH(&desc);
errout:
set_errno(ret);
return ERROR;
}