include/vfs_ext.h File Reference

---

Detailed Description

Exported VFS Definitions.

Author:

John Hodge (thePowersGang)

Go to the source code of this file.

Data Structures
struct	tVFS_ACL
	ACL Defintion Structure. More...
struct	tFInfo
	SYS_FINFO structure. More...
Defines
#define	VFS_MEMPATH_SIZE   (3 + (BITS/4)*2)
	Maximum size of a Memory Path generated by VFS_GetMemPath.
#define	VFS_KERNEL_FLAG   0x40000000
	Marks a VFS handle as belonging to the kernel.
Flags for VFS_Open
#define	VFS_OPENFLAG_EXEC   0x01
	Open for execution.
#define	VFS_OPENFLAG_READ   0x02
	Open for reading.
#define	VFS_OPENFLAG_WRITE   0x04
	Open for writing.
#define	VFS_OPENFLAG_NOLINK   0x40
	Do not resolve the final symbolic link.
#define	VFS_OPENFLAG_USER   0x80
	Open as a user.
ACL Permissions
#define	VFS_PERM_READ   0x00000001
	Readable.
#define	VFS_PERM_WRITE   0x00000002
	Writeable.
#define	VFS_PERM_APPEND   0x00000004
	Append allowed.
#define	VFS_PERM_EXECUTE   0x00000008
	Executable.
#define	VFS_PERM_ALL   0x7FFFFFFF
	All permissions granted.
#define	VFS_PERM_DENY   0x80000000
	Denies instead of granting permissions.
Enumerations
enum	eVFS_SeekDirs { SEEK_SET = 1, SEEK_CUR = 0, SEEK_END = -1 }
	VFS_Seek directions. More...
Functions
int	VFS_Init (void)
	Initialise the VFS (called by system.c).
int	VFS_Open (const char *Path, Uint Mode)
	Open a file.
void	VFS_Close (int FD)
	Close a currently open file.
int	VFS_FInfo (int FD, tFInfo *Dest, int MaxACLs)
	Get file information from an open file.
int	VFS_GetACL (int FD, tVFS_ACL *Dest)
	Gets the permissions appling to a user/group.
int	VFS_ChDir (char *Dest)
	Changes the user's current working directory.
int	VFS_ChRoot (char *New)
	Change the current virtual root for the user.
int	VFS_Seek (int FD, Sint64 Offset, int Whence)
	Change the location of the current file pointer.
Uint64	VFS_Tell (int FD)
	Returns the current file pointer.
Uint64	VFS_Read (int FD, Uint64 Length, void *Buffer)
	Reads data from a file.
Uint64	VFS_Write (int FD, Uint64 Length, const void *Buffer)
	Writes data to a file.
Uint64	VFS_ReadAt (int FD, Uint64 Offset, Uint64 Length, void *Buffer)
	Reads from a specific offset in the file.
Uint64	VFS_WriteAt (int FD, Uint64 Offset, Uint64 Length, const void *Buffer)
	Writes to a specific offset in the file.
int	VFS_IOCtl (int FD, int ID, void *Buffer)
	Sends an IOCtl request to the driver.
void	VFS_GetMemPath (char *Dest, void *Base, Uint Length)
	Creates a VFS Memory path from a pointer and size.
char *	VFS_GetTruePath (const char *Path)
	Gets the canoical (true) path of a file.
int	VFS_Mount (const char *Device, const char *MountPoint, const char *Filesystem, const char *Options)
	Mounts a filesystem.
int	VFS_MkDir (const char *Path)
	Create a new directory.
int	VFS_Symlink (const char *Name, const char *Link)
	Create a symbolic link.
int	VFS_ReadDir (int FD, char *Dest)
	Read from a directory.
int	VFS_OpenChild (Uint *Errno, int FD, const char *Name, Uint Mode)
	Opens a file via an open directory.

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Define Documentation

#define VFS_PERM_DENY   0x80000000

Denies instead of granting permissions.

Note:

Denials take precedence

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Enumeration Type Documentation

enum eVFS_SeekDirs

VFS_Seek directions.

Enumerator:

SEEK_SET	Set the current file offset.
SEEK_CUR	Seek relative to the current position.
SEEK_END	Seek from the end of the file backwards.

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Function Documentation

int VFS_ChDir

(

char *

Dest

)

Changes the user's current working directory.

Parameters:

Dest

New working directory (either absolute or relative to the current)

Returns:

Boolean Success

int VFS_ChRoot

(

char *

New

)

Change the current virtual root for the user.

Parameters:

New

New virtual root (same as VFS_ChDir but cannot go above the current virtual root)

Returns:

Boolean success

void VFS_Close

(

int

FD

)

Close a currently open file.

Parameters:

FD

Handle returned by VFS_Open

int VFS_FInfo	(	int	FD,
		tFInfo *	Dest,
		int	MaxACLs
	)

Get file information from an open file.

Parameters:

	FD	File handle returned by VFS_Open
	Dest	Destination for the read information
	MaxACLs	Number of ACL slots allocated in the Dest structure

Returns:

Boolean Success

If the NumACLs is smaller than the number of ACLs the node has, only NumACLs will be copied into Dest, but the tFInfo.numacls field will be set to the true ammount of ACLs. It is up to the user to do with this information how they like.

int VFS_GetACL	(	int	FD,
		tVFS_ACL *	Dest
	)

Gets the permissions appling to a user/group.

Parameters:

	FD	File handle returned by VFS_Open
	Dest	ACL information structure to edit

Returns:

Boolean success

This function sets the tVFS_ACL.Inv and tVFS_ACL.Perms fields to what permissions the user/group specied in tVFS_ACL.ID has on the file.

void VFS_GetMemPath	(	char *	Dest,
		void *	Base,
		Uint	Length
	)

Creates a VFS Memory path from a pointer and size.

Parameters:

	Dest	Destination for the created path
	Base	Base of the memory file
	Length	Length of the memory buffer

Note:

A maximum of VFS_MEMPATH_SIZE bytes will be required in Dest

char* VFS_GetTruePath

(

const char *

Path

)

Gets the canoical (true) path of a file.

Parameters:

Path

File path (may contain symlinks, relative elements etc.)

Returns:

Absolute path with no symlinks

int VFS_Init

(

void

)

Initialise the VFS (called by system.c).

Returns:

Boolean Success

int VFS_IOCtl	(	int	FD,
		int	ID,
		void *	Buffer
	)

Sends an IOCtl request to the driver.

Parameters:

	FD	File handle returned by VFS_Open
	ID	IOCtl call ID (driver specific)
	Buffer	Data pointer to send to the driver

Returns:

Driver specific response

int VFS_MkDir

(

const char *

Path

)

Create a new directory.

Parameters:

Path

Path to new directory (absolute or relative)

Returns:

Boolean success

Note:

The parent of the directory must exist

int VFS_Mount	(	const char *	Device,
		const char *	MountPoint,
		const char *	Filesystem,
		const char *	Options
	)

Mounts a filesystem.

Parameters:

	Device	Device to mount
	MountPoint	Location to mount
	Filesystem	Filesystem to use
	Options	Options string to pass the driver

Returns:

1 on succes, -1 on error

int VFS_Open	(	const char *	Path,
		Uint	Mode
	)

Open a file.

Parameters:

	Path	Absolute or relative path to the file
	Mode	Flags defining how to open the file

Returns:

VFS Handle (an integer) or -1 if an error occured

int VFS_OpenChild	(	Uint *	Errno,
		int	FD,
		const char *	Name,
		Uint	Mode
	)

Opens a file via an open directory.

Note:

The file to open must be a direct child of the parent

Parameters:

	Errno	Error number
	FD	Parent Directory
	Name	Child name
	Mode	Open mode

Returns:

File handle (same as returned from VFS_Open)

Uint64 VFS_Read	(	int	FD,
		Uint64	Length,
		void *	Buffer
	)

Reads data from a file.

Parameters:

	FD	File handle returned by VFS_Open
	Length	Number of bytes to read from the file
	Buffer	Destination of read data

Returns:

Number of read bytes

Uint64 VFS_ReadAt	(	int	FD,
		Uint64	Offset,
		Uint64	Length,
		void *	Buffer
	)

Reads from a specific offset in the file.

Parameters:

	FD	File handle returned by VFS_Open
	Offset	Byte offset in the file
	Length	Number of bytes to read from the file
	Buffer	Source of read data

Returns:

Number of bytes read

int VFS_ReadDir	(	int	FD,
		char *	Dest
	)

Read from a directory.

Parameters:

	FD	File handle returned by VFS_Open
	Dest	Destination array for the file name (max 255 bytes)

Returns:

Boolean Success

int VFS_Seek	(	int	FD,
		Sint64	Offset,
		int	Whence
	)

Change the location of the current file pointer.

Parameters:

	FD	File handle returned by VFS_Open
	Offset	Offset within the file to go to
	Whence	A direction from eVFS_SeekDirs

Returns:

Boolean success

int VFS_Symlink	(	const char *	Name,
		const char *	Link
	)

Create a symbolic link.

Parameters:

	Name	Name of the symbolic link
	Link	File the symlink points to

Returns:

Boolean success (Link is not tested for existence)

Uint64 VFS_Tell

(

int

FD

)

Returns the current file pointer.

Parameters:

FD

File handle returned by VFS_Open

Returns:

Current file position

Uint64 VFS_Write	(	int	FD,
		Uint64	Length,
		const void *	Buffer
	)

Writes data to a file.

Parameters:

	FD	File handle returned by VFS_Open
	Length	Number of bytes to write to the file
	Buffer	Source of written data

Returns:

Number of bytes written

Uint64 VFS_WriteAt	(	int	FD,
		Uint64	Offset,
		Uint64	Length,
		const void *	Buffer
	)

Writes to a specific offset in the file.

Parameters:

	FD	File handle returned by VFS_Open
	Offset	Byte offset in the file
	Length	Number of bytes to write to the file
	Buffer	Source of written data

Returns:

Number of bytes written