tVFS_Node Struct Reference

Represents a node (file or directory) in the VFS tree. More...

#include <vfs.h>

Data Fields
Identifiers
Fields used by the driver to identify what data this node corresponds to.
Uint64	Inode
	Inode ID (Essentially another ImplInt).
Uint	ImplInt
	Implementation Usable Integer.
void *	ImplPtr
	Implementation Usable Pointer.
Node State
Stores the misc information about the node
int	ReferenceCount
	Number of times the node is used.
Uint64	Size
	File Size.
Uint32	Flags
	File Flags.
void *	Data
	Pointer to cached data (FS Specific).
tMutex	Lock
	Node mutex.
Times
Sint64	ATime
	Last Accessed Time.
Sint64	MTime
	Last Modified Time.
Sint64	CTime
	Creation Time.
Access controll
tUID	UID
	ID of Owning User.
tGID	GID
	ID of Owning Group.
int	NumACLs
	Number of ACL entries.
tVFS_ACL *	ACLs
	Access Controll List pointer.
Common Functions
Functions that are used no matter the value of .Flags
void(*	Reference )(struct sVFS_Node *Node)
	Reference the node.
void(*	Close )(struct sVFS_Node *Node)
	Close (dereference) the node.
int(*	IOCtl )(struct sVFS_Node *Node, int Id, void *Data)
	Send an IO Control.
Buffer Functions
Functions for accessing a buffer-type file (normal file or symbolic link)
Uint64(*	Read )(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
	Read from the file.
Uint64(*	Write )(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)
	Write to the file.
Directory Functions
struct sVFS_Node *(*	FindDir )(struct sVFS_Node *Node, const char *Name)
	Find an directory entry by name.
char *(*	ReadDir )(struct sVFS_Node *Node, int Pos)
	Read from a directory.
int(*	MkNod )(struct sVFS_Node *Node, const char *Name, Uint Flags)
	Create a node in a directory.
int(*	Relink )(struct sVFS_Node *Node, const char *OldName, const char *NewName)
	Relink (Rename/Remove) a file/directory.
int(*	Link )(struct sVFS_Node *Node, struct sVFS_Node *Child, const char *NewName)
	Link a node to a name.

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Detailed Description

Represents a node (file or directory) in the VFS tree.

This structure provides the VFS with the functions required to read/write the file (or directory) that it represents.

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Field Documentation

void(* tVFS_Node::Close)(struct sVFS_Node *Node)

Close (dereference) the node.

Parameters:

Node

Pointer to this node

Usually .Close is used to write any changes to the node back to the persistent storage.

void* tVFS_Node::Data

Pointer to cached data (FS Specific).

Note:

The Inode_* functions will free when the node is uncached this if needed

struct sVFS_Node*(* tVFS_Node::FindDir)(struct sVFS_Node *Node, const char *Name) [read]

Find an directory entry by name.

Parameters:

	Node	Pointer to this node
	Name	Name of the file wanted

Returns:

Pointer to the requested node or NULL if it cannot be found

Note:

The node returned must be accessable until tVFS_Node.Close is called and ReferenceCount reaches zero.

int(* tVFS_Node::IOCtl)(struct sVFS_Node *Node, int Id, void *Data)

Send an IO Control.

Parameters:

	Node	Pointer to this node
	Id	IOCtl call number
	Data	Pointer to data to pass to the driver

Returns:

Implementation defined

int(* tVFS_Node::Link)(struct sVFS_Node *Node, struct sVFS_Node *Child, const char *NewName)

Link a node to a name.

Parameters:

	Node	Pointer to this node (directory)
	Child	Node to create a new link to
	NewName	Name for the new link

Returns:

Zeron on success, non-zero on error (see errno.h)

tMutex tVFS_Node::Lock

Node mutex.

Note:

Provided for the Filesystem driver's use

int(* tVFS_Node::MkNod)(struct sVFS_Node *Node, const char *Name, Uint Flags)

Create a node in a directory.

Parameters:

	Node	Pointer to this node
	Name	Name of the new child
	Flags	Flags to apply to the new child (directory or symlink)

Returns:

Zero on Success, non-zero on error (see errno.h)

Uint64(* tVFS_Node::Read)(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)

Read from the file.

Parameters:

	Node	Pointer to this node
	Offset	Byte offset in the file
	Length	Number of bytes to read
	Buffer	Destination for read data

Returns:

Number of bytes read

char*(* tVFS_Node::ReadDir)(struct sVFS_Node *Node, int Pos)

Read from a directory.

Parameters:

	Node	Pointer to this node
	Pos	Offset in the directory

Returns:

Pointer to the name of the item on the heap (will be freed by the caller). If the directory end has been reached, NULL will be returned. If an item is required to be skipped either &NULLNode, VFS_SKIP or VFS_SKIPN(0...1023) will be returned.

void(* tVFS_Node::Reference)(struct sVFS_Node *Node)

Reference the node.

Parameters:

Node

Pointer to this node

int(* tVFS_Node::Relink)(struct sVFS_Node *Node, const char *OldName, const char *NewName)

Relink (Rename/Remove) a file/directory.

Parameters:

	Node	Pointer to this node
	OldName	Name of the item to move/delete
	NewName	New name (or NULL if unlinking is wanted)

Returns:

Zero on Success, non-zero on error (see errno.h)

Uint64(* tVFS_Node::Write)(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer)

Write to the file.

Parameters:

	Node	Pointer to this node
	Offset	Byte offser in the file
	Length	Number of bytes to write
	Buffer	Source of written data

Returns:

Number of bytes read

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The documentation for this struct was generated from the following file:

• include/vfs.h