moss.fs
Class MHostFS

java.lang.Object
  moss.fs.MHostFS

All Implemented Interfaces:

MFSOps

public class MHostFS
extends java.lang.Object
implements MFSOps

this class implements the "host" file-system. This mirrors the host file-system; the option specifies which root to mount if there are many.

Constructor Summary

MHostFS()

Method Summary

int	access(java.lang.String path, int amode) tests for access to a file
int	link(java.lang.String oldpath, java.lang.String newpath) creates a `hard-link'
int	mkdir(java.lang.String path, int flags) creates a directory in the file-system
int	mknod(java.lang.String path, int mode, int majmin) creates a special file on the file-system
int	mount(java.lang.String mount_path, java.lang.String[] options) called when the object file-system is mounted.
int	open(java.lang.String path, MFile handle, int flags, int mode) called to open a file.
int	opendir(java.lang.String path, MFile handle) called to open a directory (read-only!).
int	readlink(java.lang.String path, byte[] buf, int buflen) reads the contents of a symbolic-link on the file-system
int	rmdir(java.lang.String path) removes a directory from the file-system (must be empty)
int	stat(java.lang.String path, MInode statbuf) retrieves information about a name on the file-system
int	symlink(java.lang.String oldpath, java.lang.String newpath) creates a symbolic link
int	umount(java.lang.String[] options) this is called before the object file-system is un-mounted.
int	unlink(java.lang.String path) removes a name from the file-system
int	utime(java.lang.String path, long[] times) sets access and modification times for a file (inode)

Methods inherited from class java.lang.Object

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

Constructor Detail

MHostFS

public MHostFS()

Method Detail

mount

public int mount(java.lang.String mount_path,
                 java.lang.String[] options)

called when the object file-system is mounted. Performs specific initialisation.

Specified by:

mount in interface MFSOps

Parameters:

mount_path - full path from the root (/) to where this is being mounted. A single "/" indicates that this is being mounted as the root file-system.

options - file-system specific options

Returns:

0 on success, or < 0 indicating error

umount

public int umount(java.lang.String[] options)

this is called before the object file-system is un-mounted.

Specified by:

umount in interface MFSOps

Parameters:

options - file-system specific un-mounting options

Returns:

0 on success, or < 0 indicating error

open

public int open(java.lang.String path,
                MFile handle,
                int flags,
                int mode)

called to open a file.

Specified by:

open in interface MFSOps

Parameters:

path - relative path to the file (e.g. `etc/passwd' for the root file-system)

handle - file-handle to be associated with this file

flags - open flags

mode - file mode if creating

Returns:

0 on success, or < 0 indicating error

opendir

public int opendir(java.lang.String path,
                   MFile handle)

called to open a directory (read-only!).

Specified by:

opendir in interface MFSOps

Parameters:

path - relative path to the directory (e.g. `etc/init.d' for the root file-system)

handle - file-handle to be associated with this directory

Returns:

0 on success, or < 0 indicating error

mkdir

public int mkdir(java.lang.String path,
                 int flags)

creates a directory in the file-system

Specified by:

mkdir in interface MFSOps

Parameters:

path - relative path to the directory to be created

flags - flags (mode)

Returns:

0 on success, or < 0 indicating error

unlink

public int unlink(java.lang.String path)

removes a name from the file-system

Specified by:

unlink in interface MFSOps

Parameters:

path - relative path to the name to be removed

Returns:

0 on success, or < 0 indicating error

rmdir

public int rmdir(java.lang.String path)

removes a directory from the file-system (must be empty)

Specified by:

rmdir in interface MFSOps

Parameters:

path - relative path to the directory to be removed

Returns:

0 on success, or < 0 indicating error

link

public int link(java.lang.String oldpath,
                java.lang.String newpath)

creates a `hard-link'

Specified by:

link in interface MFSOps

Parameters:

oldpath - existing relative path (e.g. local/packages/nmh for "usr" file-system)

newpath - new relative path

Returns:

0 on success, or < 0 indicating error

symlink

public int symlink(java.lang.String oldpath,
                   java.lang.String newpath)

creates a symbolic link

Specified by:

symlink in interface MFSOps

Parameters:

oldpath - full path to existing name (e.g. /usr/local/packages/nmh-1.4 for "usr" file-system)

newpath - relative path to new link (e.g. local/packages/nmh for "usr" file-system)

Returns:

0 on success, or < 0 indicating error

mknod

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

creates a special file on the file-system

Specified by:

mknod in interface MFSOps

Parameters:

path - relative path to file to create

mode - file mode flags

majmin - major and minor numbers `((major << 16) | minor)' for block/char special files, otherwise ignored.

Returns:

0 on success, or < 0 indicating error

readlink

public int readlink(java.lang.String path,
                    byte[] buf,
                    int buflen)

reads the contents of a symbolic-link on the file-system

Specified by:

readlink in interface MFSOps

Parameters:

path - relative path to symbolic link on file-system

buf - buffer where the link data is stored

buflen - maximum number of bytes to write into `buf'

Returns:

number of bytes read on success, or < 0 indicating error

utime

public int utime(java.lang.String path,
                 long[] times)

sets access and modification times for a file (inode)

Specified by:

utime in interface MFSOps

Parameters:

path - relative path to name

times - array of two `long's that are the access and modification times respectively

Returns:

0 on success, or < 0 indicating error

stat

public int stat(java.lang.String path,
                MInode statbuf)

retrieves information about a name on the file-system

Specified by:

stat in interface MFSOps

Parameters:

path - relative path to name

statbuf - buffer in which information is placed

Returns:

0 on success, or < 0 indicating error

access

public int access(java.lang.String path,
                  int amode)

tests for access to a file

Specified by:

access in interface MFSOps

Parameters:

path - relative path to file/directory

amode - access mode

Returns:

0 on success, or < 0 indicating error