px4-firmware/nuttx/fs/nxffs/nxffs_unlink.c

188 lines
5.7 KiB
C

/****************************************************************************
* fs/nxffs/nxffs_unlink.c
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* References: Linux/Documentation/filesystems/romfs.txt
*
* 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 <string.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/fs/fs.h>
#include <nuttx/mtd.h>
#include "nxffs.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Public Types
****************************************************************************/
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nxffs_rminode
*
* Description:
* Remove an inode from FLASH. This is the internal implementation of
* the file system unlinke operation.
*
* Input Parameters:
* volume - Describes the NXFFS volume.
* name - the name of the inode to be deleted.
*
* Returned Value:
* Zero is returned if the inode is successfully deleted. Otherwise, a
* negated errno value is returned indicating the nature of the failure.
*
****************************************************************************/
int nxffs_rminode(FAR struct nxffs_volume_s *volume, FAR const char *name)
{
FAR struct nxffs_ofile_s *ofile;
FAR struct nxffs_inode_s *inode;
struct nxffs_entry_s entry;
int ret;
/* Check if the file is open */
ofile = nxffs_findofile(volume, name);
if (ofile)
{
/* We can't remove the inode if it is open */
fdbg("Inode '%s' is open\n", name);
ret = -EBUSY;
goto errout;
}
/* Find the NXFFS inode */
ret = nxffs_findinode(volume, name, &entry);
if (ret < 0)
{
fdbg("Inode '%s' not found\n", name);
goto errout;
}
/* Set the position to the FLASH offset of the file header (nxffs_findinode
* should have left the block in the cache).
*/
nxffs_ioseek(volume, entry.hoffset);
/* Make sure the the block is in the cache */
ret = nxffs_rdcache(volume, volume->ioblock);
if (ret < 0)
{
fdbg("Failed to read data into cache: %d\n", ret);
goto errout_with_entry;
}
/* Change the file status... it is no longer valid */
inode = (FAR struct nxffs_inode_s *)&volume->cache[volume->iooffset];
inode->state = INODE_STATE_DELETED;
/* Then write the cached block back to FLASH */
ret = nxffs_wrcache(volume);
if (ret < 0)
{
fdbg("Failed to read data into cache: %d\n", ret);
}
errout_with_entry:
nxffs_freeentry(&entry);
errout:
return ret;
}
/****************************************************************************
* Name: nxffs_unlink
*
* Description: Remove a file
*
****************************************************************************/
int nxffs_unlink(FAR struct inode *mountpt, FAR const char *relpath)
{
FAR struct nxffs_volume_s *volume;
int ret;
fvdbg("Entry\n");
/* Sanity checks */
DEBUGASSERT(mountpt && mountpt->i_private);
/* Get the mountpoint private data from the NuttX inode structure */
volume = mountpt->i_private;
ret = sem_wait(&volume->exclsem);
if (ret != OK)
{
goto errout;
}
/* Then remove the NXFFS inode */
ret = nxffs_rminode(volume, relpath);
sem_post(&volume->exclsem);
errout:
return ret;
}