// vfs.h
// Author: Josh Holtrop
// Date: 08/22/04
// Modified: 12/21/04

#ifndef __HOS_VFS_H__
#define __HOS_VFS_H__ __HOS_VFS_H__

#include "hos_defines.h"
#include "fs/devices.h"

#define FS_EXT2 1
#define VFS_MAX_FS 10

#define VFS_FT_UNKNOWN	0
#define VFS_FT_FILE	1
#define VFS_FT_DIR	2
#define VFS_FT_CHAR	3
#define VFS_FT_BLOCK	4
#define VFS_FT_FIFO	5
#define VFS_FT_SOCK	6
#define VFS_FT_SYMLINK	7

#define VFS_PERMS_OX		0x0001
#define VFS_PERMS_OW		0x0002
#define VFS_PERMS_OR		0x0004
#define VFS_PERMS_GX		0x0008
#define VFS_PERMS_GW		0x0010
#define VFS_PERMS_GR		0x0020
#define VFS_PERMS_UX		0x0040
#define VFS_PERMS_UW		0x0080
#define VFS_PERMS_UR		0x0100
#define VFS_PERMS_STICKY	0x0200
#define VFS_PERMS_SGID		0x0400
#define VFS_PERMS_SUID		0x0800

#define EOF 1000000

typedef u64_t vfs_inode_t;

/* Structure to hold information about a mount point */
struct vfs_mount_s
{
	int	refs;
	void	*super;
	int	fs;
	major_t major;
	minor_t minor;
	char	*mountPoint;
	vfs_inode_t	vfs_mount_inode;
	vfs_inode_t	vfs_up_inode;
	vfs_inode_t	vfs_root_inode;
	struct vfs_mount_s	*next;
	struct vfs_mount_s	*prev;
};
typedef struct vfs_mount_s vfs_mount_t;

typedef struct
{
	u16_t	type;			// file type, of VFS_FILE_TYPE_*
	u32_t	size;
	u32_t	inode;
	u16_t	permissions;
	u16_t	uid;
	u16_t	gid;
	u32_t	atime;
	u32_t	mtime;
	u32_t	ctime;
	u16_t	links;
	u32_t	dev;
} vfs_stat_t;

typedef struct
{
	vfs_mount_t *mount;
	void *fs_data;
} vfs_open_file_t;

typedef struct
{
	char	name[257];
	u32_t	inode_number;		// relative inode number returned from fs
} vfs_dir_entry_t;

typedef struct
{
	vfs_mount_t *mount;
	u32_t inode;
} vfs_file_addr_t;

/* Every filesystem must provide pointers to its respective functions in a structure like this */
typedef struct
{
	void	*(*mount_super)(major_t major, minor_t minor);
	int	(*umount_super)(vfs_mount_t *mount);
	int	(*stat)(vfs_mount_t *mount, u32_t inode_number, vfs_stat_t *stat);
	u32_t	(*get_root_inode)(vfs_mount_t *mount);
	int	(*link_deref)(vfs_mount_t *mount, u32_t inode_number, char *link);
	int	(*free_inodes)(vfs_mount_t *mount);
	int	(*total_inodes)(vfs_mount_t *mount);
	int	(*free_blocks)(vfs_mount_t *mount);
	int	(*total_blocks)(vfs_mount_t *mount);

	u32_t	(*alloc_inode)(vfs_mount_t *mount);
	int	(*free_inode)(vfs_mount_t *mount, u32_t inode_number);
	u32_t	(*alloc_block)(vfs_mount_t *mount);
	int	(*free_block)(vfs_mount_t *mount, u32_t block_number);

	int	(*open_dir)(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *dir);
	int	(*read_dir)(vfs_mount_t *mount, vfs_open_file_t *dir, vfs_dir_entry_t *dentry);
	int	(*close_dir)(vfs_mount_t *mount, vfs_open_file_t *dir);

	int	(*open_file)(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *open_file);
	int	(*read_file)(vfs_mount_t *mount, vfs_open_file_t *open_file);
	int	(*close_file)(vfs_mount_t *mount, vfs_open_file_t *open_file);

	int	(*open_block_file)(vfs_mount_t *mount, u32_t inode_number, vfs_open_file_t *open_file);
	int	(*read_block_file)(vfs_mount_t *mount, vfs_open_file_t *open_file, void *buffer);
	int	(*block_file_seek)(vfs_mount_t *mount, vfs_open_file_t *open_file, u32_t block_number);
	int	(*close_block_file)(vfs_mount_t *mount, vfs_open_file_t *open_file);

} vfs_fs_t;


int	vfs_init();
int	vfs_mount(major_t maj, minor_t min, int fsType, char *mountPoint);
int	vfs_umount(char *mountPoint);
int	vfs_register_fs(int fsn, vfs_fs_t *fs);
int	vfs_umount(char *mountPoint);
vfs_inode_t	vfs_get_inode_number(char *path);
vfs_inode_t	vfs_get_inode_number_rel(vfs_inode_t dir_inode, char *path);
vfs_inode_t vfs_real_inode(vfs_inode_t vfs_inode);
vfs_file_addr_t vfs_get_file_addr(vfs_inode_t vfs_inode);
vfs_inode_t	vfs_entry_lookup(vfs_inode_t dir_inode, char *entry);

int	vfs_mount_count();
vfs_mount_t *vfs_get_mount(int index);
int	vfs_free_inodes(vfs_mount_t *mount);
int	vfs_total_inodes(vfs_mount_t *mount);
int	vfs_free_blocks(vfs_mount_t *mount);
int	vfs_total_blocks(vfs_mount_t *mount);

vfs_inode_t	vfs_alloc_inode(vfs_mount_t *mount);
int	vfs_free_inode(vfs_mount_t *mount, u32_t inode_number);
u32_t	vfs_alloc_block(vfs_mount_t *mount);
int	vfs_free_block(vfs_mount_t *mount, u32_t block_number);


int	vfs_link_deref(vfs_inode_t vfs_inode, char *link);

int	vfs_stat(char *file, vfs_stat_t *stat);
int	vfs_stat_inode(vfs_inode_t vfs_inode, vfs_stat_t *stat);

vfs_open_file_t *vfs_open_dir(char *path);
vfs_open_file_t *vfs_open_dir_inode(vfs_inode_t inode);
int	vfs_read_dir(vfs_open_file_t *open_dir, vfs_dir_entry_t *dentry);
int	vfs_close_dir(vfs_open_file_t *open_dir);

vfs_open_file_t *vfs_open_block_file(char *file);
vfs_open_file_t *vfs_open_block_file_inode(vfs_inode_t vfs_inode);
int	vfs_read_block_file(vfs_open_file_t *open_file, void *buffer);
int	vfs_block_file_seek(vfs_open_file_t *open_file, u32_t block_number);
int	vfs_close_block_file(vfs_open_file_t *open_file);

#endif