org.basex.fuse
Class DeepFuse

java.lang.Object
  org.basex.fuse.DeepFuse

Direct Known Subclasses:

DeepFS

public abstract class DeepFuse
extends java.lang.Object

Interface to filesystem in userspace framework.

Author:

Workgroup DBIS, University of Konstanz 2005-09, ISC License, Alexander Holupirek, alex@holupirek.de

Constructor Summary

DeepFuse()

Method Summary

abstract int	access(java.lang.String path, int mode) Checks file access permissions.
abstract int	bmap(java.lang.String path, long blocksize, long idx) Maps block index within file to block index within device.
abstract int	chmod(java.lang.String path, int mode) Changes the permission bits of a file.
abstract int	chown(java.lang.String path, int uid, int gid) Changes the owner and group of a file.
abstract int	create(java.lang.String path, int mode) Creates and open a file.
abstract int	destroy() Cleans up filesystem.
abstract int	fgetattr(java.lang.String path) Gets attributes from an open file.
abstract int	flush(java.lang.String path) Possibly flushes cached data.
abstract int	fsync(java.lang.String path) Synchronizes file contents.
abstract int	fsyncdir(java.lang.String path) Synchronizes directory contents.
abstract int	ftruncate(java.lang.String path, long off) Changes the size of an open file.
abstract int	getattr(java.lang.String path) Gets file attributes.
abstract int	getxattr(java.lang.String path) Gets extended attributes.
abstract int	link(java.lang.String name1, java.lang.String name2) Creates a hard link to a file.
abstract int	listxattr(java.lang.String path) Lists extended attributes.
abstract int	lock(java.lang.String path, int cmd) Performs POSIX file locking operation.
abstract int	mkdir(java.lang.String path, int mode) Creates a directory.
abstract int	mknod(java.lang.String path, int mode, int dev) Creates a file node.
abstract int	open(java.lang.String path) File open operation.
abstract int	opendir(java.lang.String path) Opens directory.
abstract byte[]	read(java.lang.String path, int length, int offset) Reads data from an open file.
abstract java.lang.String	readdir(java.lang.String path, int offset) Reads directory.
abstract java.lang.String	readlink(java.lang.String path) Reads the target of a symbolic link.
abstract int	release(java.lang.String path) Releases an open file.
abstract int	releasedir(java.lang.String path) Releases directory.
abstract int	removexattr(java.lang.String path) Removes extended attributes.
abstract int	rename(java.lang.String from, java.lang.String to) Renames a file.
abstract int	rmdir(java.lang.String path) Removes a directory file.
abstract int	setxattr(java.lang.String path) Sets extended attributes.
abstract int	statfs(java.lang.String path) Gets file system statistics.
abstract int	symlink(java.lang.String from, java.lang.String to) Makes symbolic link to a file.
abstract int	truncate(java.lang.String path, long off) Changes the size of a file.
abstract int	unlink(java.lang.String path) Removes a file.
abstract int	utimens(java.lang.String path) Changes the access and modification times of a file with nanosecond resolution.
abstract int	write(java.lang.String path, int length, int offset, byte[] data) Writes data to an open file.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DeepFuse

public DeepFuse()

Method Detail

getattr

public abstract int getattr(java.lang.String path)

Gets file attributes.

Parameters:

path - to the file the stat information is requested for

Returns:

int id of node/inode of the requested file

readlink

public abstract java.lang.String readlink(java.lang.String path)

Reads the target of a symbolic link.

Parameters:

path - to the link

Returns:

String link target

mknod

public abstract int mknod(java.lang.String path,
                          int mode,
                          int dev)

Creates a file node. This is called for creation of all non-directory, non-symlink nodes. If the filesystem defines a create() method, then for regular files that will be called instead.

Parameters:

path - name of the file to be created.

mode - specifies both the permissions to use and the type of node to be created.

dev - If the file type is S_IFCHR or S_IFBLK then dev specifies the major and minor numbers of the newly created device special file; otherwise it is ignored.

Returns:

zero on success, or -1 if an error occurred (in which case, errno is set appropriately).

mkdir

public abstract int mkdir(java.lang.String path,
                          int mode)

Creates a directory.

Parameters:

path - to directory to be created

mode - permissions for directory

Returns:

node id, or -1 if an error occurred (in which case, errno is set appropriately).

unlink

public abstract int unlink(java.lang.String path)

Removes a file.

Parameters:

path - to file to be removed

Returns:

zero on success, or -1 if an error occurred (in which case, errno is set appropriately).

rmdir

public abstract int rmdir(java.lang.String path)

Removes a directory file.

Parameters:

path - to file to be removed

Returns:

zero on success, or -1 if an error occurred (in which case, errno is set appropriately).

symlink

public abstract int symlink(java.lang.String from,
                            java.lang.String to)

Makes symbolic link to a file.

Parameters:

from - link source

to - link target

Returns:

zero on success, or -1 if an error occurred (in which case, errno is set appropriately).

rename

public abstract int rename(java.lang.String from,
                           java.lang.String to)

Renames a file.

Parameters:

from - path to file to be renamed

to - new name

Returns:

zero on success, or -1 if an error occurred (in which case, errno is set appropriately).

link

public abstract int link(java.lang.String name1,
                         java.lang.String name2)

Creates a hard link to a file.

Parameters:

name1 - link source

name2 - link target

Returns:

zero on success, or -1 if an error occurred (in which case, errno is set appropriately).

chmod

public abstract int chmod(java.lang.String path,
                          int mode)

Changes the permission bits of a file.

Parameters:

path - name of the file

mode - permissions to be set

Returns:

zero on success, or -1 if an error occurred

chown

public abstract int chown(java.lang.String path,
                          int uid,
                          int gid)

Changes the owner and group of a file.

Parameters:

path - name of the file

uid - owner

gid - group

Returns:

zero on success, or -1 if an error occurred

truncate

public abstract int truncate(java.lang.String path,
                             long off)

Changes the size of a file.

Parameters:

path - name of the file

off - size to be set

Returns:

zero on success, or -1 if an error occurred

open

public abstract int open(java.lang.String path)

File open operation.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

read

public abstract byte[] read(java.lang.String path,
                            int length,
                            int offset)

Reads data from an open file.

Parameters:

path - name of the file

length - number of bytes to read

offset - from which to read

Returns:

zero on success, or -1 if an error occurred

write

public abstract int write(java.lang.String path,
                          int length,
                          int offset,
                          byte[] data)

Writes data to an open file.

Parameters:

path - name of the file

length - number of bytes to write

offset - from which to write

data - buffer from which to write

Returns:

zero on success, or -1 if an error occurred

statfs

public abstract int statfs(java.lang.String path)

Gets file system statistics.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

flush

public abstract int flush(java.lang.String path)

Possibly flushes cached data. BIG NOTE: This is not equivalent to fsync(). It's not a request to sync dirty data.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

release

public abstract int release(java.lang.String path)

Releases an open file.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

fsync

public abstract int fsync(java.lang.String path)

Synchronizes file contents.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

setxattr

public abstract int setxattr(java.lang.String path)

Sets extended attributes.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

getxattr

public abstract int getxattr(java.lang.String path)

Gets extended attributes.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

listxattr

public abstract int listxattr(java.lang.String path)

Lists extended attributes.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

removexattr

public abstract int removexattr(java.lang.String path)

Removes extended attributes.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

opendir

public abstract int opendir(java.lang.String path)

Opens directory.

Parameters:

path - name of the file

Returns:

the number of directories or -1 if an error occurred

readdir

public abstract java.lang.String readdir(java.lang.String path,
                                         int offset)

Reads directory.

Parameters:

path - name of the directory to read

offset - of directory entry requested

Returns:

name of directory entry or null on failure

releasedir

public abstract int releasedir(java.lang.String path)

Releases directory.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

fsyncdir

public abstract int fsyncdir(java.lang.String path)

Synchronizes directory contents.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

destroy

public abstract int destroy()

Cleans up filesystem. Called on filesystem exit.

Returns:

zero on success, or -1 if an error occurred

access

public abstract int access(java.lang.String path,
                           int mode)

Checks file access permissions.

Parameters:

path - name of the file

mode - permission to check

Returns:

zero on success, or -1 if an error occurred

create

public abstract int create(java.lang.String path,
                           int mode)

Creates and open a file.

Parameters:

path - for the file to be created

mode - of file (directory, regular file ..., permission bits)

Returns:

int id of newly created file or -1 on failure

ftruncate

public abstract int ftruncate(java.lang.String path,
                              long off)

Changes the size of an open file.

Parameters:

path - name of the file

off - new file size

Returns:

zero on success, or -1 if an error occurred

fgetattr

public abstract int fgetattr(java.lang.String path)

Gets attributes from an open file. This method is called instead of the getattr() method if the file information is available.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

lock

public abstract int lock(java.lang.String path,
                         int cmd)

Performs POSIX file locking operation.

Parameters:

path - name of the file

cmd - locking command id

Returns:

zero on success, or -1 if an error occurred

utimens

public abstract int utimens(java.lang.String path)

Changes the access and modification times of a file with nanosecond resolution.

Parameters:

path - name of the file

Returns:

zero on success, or -1 if an error occurred

bmap

public abstract int bmap(java.lang.String path,
                         long blocksize,
                         long idx)

Maps block index within file to block index within device.

Parameters:

path - name of the file

blocksize - block size

idx - block index

Returns:

zero on success, or -1 if an error occurred