+++ /dev/null
-/*
- * Acess2
- * VFS Common Header
- */
-/**
- * \file vfs.h
- * \brief Acess VFS Layer
- *
- * The Acess Virtual File System (VFS) provides abstraction of multiple
- * physical filesystems, network storage and devices (both hardware and
- * virtual) to the user.
- *
- * The core of the VFS is the concept of a \ref tVFS_Node "VFS Node".
- * A VFS Node represents a "file" in the VFS tree, this can be any sort
- * of file (an ordinary file, a directory, a symbolic link or a device)
- * depending on the bits set in the \ref tVFS_Node.Flags Flags field.
- * - For more information see "VFS Node Flags"
- */
-#ifndef _VFS_H
-#define _VFS_H
-
-#include <acess.h>
-
-/**
- * \name tVFS_Node Flags
- * \brief Flag values for tVFS_Node.Flags
- * \{
- */
-//! \todo Is this still needed
-#define VFS_FFLAG_READONLY 0x01 //!< Readonly File
-/**
- * \brief Directory Flag
- *
- * This flag marks the tVFS_Node as describing a directory, and says
- * that the tVFS_Node.FindDir, tVFS_Node.ReadDir, tVFS_Node.MkNod and
- * tVFS_Node.Relink function pointers are valid.
- * For a directory the tVFS_Node.Size field contains the number of files
- * within the directory, or -1 for undetermined.
- */
-#define VFS_FFLAG_DIRECTORY 0x02
-/**
- * \brief Symbolic Link Flag
- *
- * Marks a file as a symbolic link
- */
-#define VFS_FFLAG_SYMLINK 0x04
-/**
- * \brief Set User ID Flag
- *
- * Allows an executable file to change it's executing user to the file's
- * owner.
- * In the case of a directory, it means that all immediate children will
- * inherit the UID of the parent.
- */
-#define VFS_FFLAG_SETUID 0x08
-/**
- * \brief Set Group ID Flag
- *
- * Allows an executable file to change it's executing group to the file's
- * owning group.
- * In the case of a directory, it means that all immediate children will
- * inherit the GID of the parent.
- */
-#define VFS_FFLAG_SETGID 0x10
-/**
- * \}
- */
-
-/**
- * \brief VFS Node
- *
- * This structure provides the VFS with the functions required to read/write
- * the file (or directory) that it represents.
- */
-typedef struct sVFS_Node
-{
- /**
- * \name Identifiers
- * \brief 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
- /**
- * \}
- */
-
- /**
- * \name Node State
- * \brief Stores the misc information about the node
- * \{
- */
- int ReferenceCount; //!< Number of times the node is used
-
- Uint64 Size; //!< File Size
-
- Uint32 Flags; //!< File Flags
- /**
- * \}
- */
-
- /**
- * \name Times
- * \{
- */
- Sint64 ATime; //!< Last Accessed Time
- Sint64 MTime; //!< Last Modified Time
- Sint64 CTime; //!< Creation Time
- /**
- * \}
- */
-
- /**
- * \name 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
- /**
- * \}
- */
-
- /**
- * \name Common Functions
- * \brief Functions that are used no matter the value of .Flags
- * \{
- */
- /**
- * \brief Reference the node
- * \param Node Pointer to this node
- */
- void (*Reference)(struct sVFS_Node *Node);
- /**
- * \brief Close (dereference) the node
- * \param Node Pointer to this node
- *
- * Usually .Close is used to write any changes to the node back to
- * the persistent storage.
- */
- void (*Close)(struct sVFS_Node *Node);
-
- /**
- * \brief Send an IO Control
- * \param Node Pointer to this node
- * \param Id IOCtl call number
- * \param Data Pointer to data to pass to the driver
- * \return Implementation defined
- */
- int (*IOCtl)(struct sVFS_Node *Node, int Id, void *Data);
-
- /**
- * }
- */
-
- /**
- * \name Buffer Functions
- * \brief Functions for accessing a buffer-type file (normal file or
- * symbolic link)
- * \{
- */
-
- /**
- * \brief Read from the file
- * \param Node Pointer to this node
- * \param Offset Byte offset in the file
- * \param Length Number of bytes to read
- * \param Buffer Destination for read data
- * \return Number of bytes read
- */
- Uint64 (*Read)(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
- /**
- * \brief Write to the file
- * \param Node Pointer to this node
- * \param Offset Byte offser in the file
- * \param Length Number of bytes to write
- * \param Buffer Source of written data
- * \return Number of bytes read
- */
- Uint64 (*Write)(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
-
- /**
- * }
- */
-
- /**
- * \name Directory Functions
- * \{
- */
- /**
- * \brief Find an directory entry by name
- * \param Node Pointer to this node
- * \param Name Name of the file wanted
- * \return 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.
- */
- struct sVFS_Node *(*FindDir)(struct sVFS_Node *Node, char *Name);
-
- /**
- * \brief Read from a directory
- * \param Node Pointer to this node
- * \param Pos Offset in the directory
- * \return 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.
- */
- char *(*ReadDir)(struct sVFS_Node *Node, int Pos);
-
- /**
- * \brief Create a node in a directory
- * \param Node Pointer to this node
- * \param Name Name of the new child
- * \param Flags Flags to apply to the new child (directory or symlink)
- * \return Boolean success
- */
- int (*MkNod)(struct sVFS_Node *Node, char *Name, Uint Flags);
-
- /**
- * \brief Relink (Rename/Remove) a file/directory
- * \param Node Pointer to this node
- * \param OldName Name of the item to move/delete
- * \param NewName New name (or NULL if unlinking is wanted)
- * \return Zero on Success, non-zero on error (see errno.h)
- */
- int (*Relink)(struct sVFS_Node *Node, char *OldName, char *NewName);
-
- /**
- * }
- */
-} tVFS_Node;
-
-/**
- * \brief VFS Driver (Filesystem) Definition
- */
-typedef struct sVFS_Driver
-{
- //! \brief Unique Identifier for this filesystem type
- char *Name;
- //! \brief Flags applying to this driver
- Uint Flags;
-
- //! \brief Callback to mount a device
- tVFS_Node *(*InitDevice)(char *Device, char **Options);
- //! \brief Callback to unmount a device
- void (*Unmount)(tVFS_Node *Node);
- //! \brief Used internally (next driver in the chain)
- struct sVFS_Driver *Next;
-} tVFS_Driver;
-
-// === GLOBALS ===
-//! \brief Maximum number of elements that can be skipped in one return
-#define VFS_MAXSKIP ((void*)1024)
-//! \brief Skip a single entry in readdir
-#define VFS_SKIP ((void*)1)
-//! \brief Skip \a n entries in readdir
-#define VFS_SKIPN(n) ((void*)(n))
-
-extern tVFS_Node NULLNode; //!< NULL VFS Node (Ignored/Skipped)
-/**
- * \name Static ACLs
- * \brief Simple ACLs to aid writing drivers
- * \{
- */
-extern tVFS_ACL gVFS_ACL_EveryoneRWX; //!< Everyone Read/Write/Execute
-extern tVFS_ACL gVFS_ACL_EveryoneRW; //!< Everyone Read/Write
-extern tVFS_ACL gVFS_ACL_EveryoneRX; //!< Everyone Read/Execute
-extern tVFS_ACL gVFS_ACL_EveryoneRO; //!< Everyone Read only
-/**
- * \}
- */
-
-// === FUNCTIONS ===
-/**
- * \fn int VFS_AddDriver(tVFS_Driver *Info)
- * \brief Registers the driver with the DevFS layer
- * \param Info Driver information structure
- */
-extern int VFS_AddDriver(tVFS_Driver *Info);
-/**
- * \fn tVFS_Driver *VFS_GetFSByName(char *Name)
- * \brief Get the information structure of a driver given its name
- * \param Name Name of filesystem driver to find
- */
-extern tVFS_Driver *VFS_GetFSByName(char *Name);
-/**
- * \fn tVFS_ACL *VFS_UnixToAcessACL(Uint Mode, Uint Owner, Uint Group)
- * \brief Transforms Unix Permssions into Acess ACLs
- * \param Mode Unix RWXrwxRWX mask
- * \param Owner UID of the file's owner
- * \param Group GID of the file's owning group
- * \return An array of 3 Acess ACLs
- */
-extern tVFS_ACL *VFS_UnixToAcessACL(Uint Mode, Uint Owner, Uint Group);
-
-// --- Node Cache --
-/**
- * \name Node Cache
- * \brief Functions to allow a node to be cached in memory by the VFS
- *
- * These functions store a node for the driver, to prevent it from having
- * to re-generate the node on each call to FindDir. It also allows for
- * fast cleanup when a filesystem is unmounted.
- * \{
- */
-/**
- * \fn int Inode_GetHandle()
- * \brief Gets a unique handle to the Node Cache
- * \return A unique handle for use for the rest of the Inode_* functions
- */
-extern int Inode_GetHandle();
-/**
- * \fn tVFS_Node *Inode_GetCache(int Handle, Uint64 Inode)
- * \brief Gets an inode from the node cache
- * \param Handle A handle returned by Inode_GetHandle()
- * \param Inode Value of the Inode field of the ::tVFS_Node you want
- * \return A pointer to the cached node
- */
-extern tVFS_Node *Inode_GetCache(int Handle, Uint64 Inode);
-/**
- * \fn tVFS_Node *Inode_CacheNode(int Handle, tVFS_Node *Node)
- * \brief Caches a node in the Node Cache
- * \param Handle A handle returned by Inode_GetHandle()
- * \param Node A pointer to the node to be cached (a copy is taken)
- * \return A pointer to the node in the node cache
- */
-extern tVFS_Node *Inode_CacheNode(int Handle, tVFS_Node *Node);
-/**
- * \fn int Inode_UncacheNode(int Handle, Uint64 Inode)
- * \brief Dereferences (and removes if needed) a node from the cache
- * \param Handle A handle returned by Inode_GetHandle()
- * \param Inode Value of the Inode field of the ::tVFS_Node you want to remove
- */
-extern void Inode_UncacheNode(int Handle, Uint64 Inode);
-/**
- * \fn void Inode_ClearCache(int Handle)
- * \brief Clears the cache for a handle
- * \param Handle A handle returned by Inode_GetHandle()
- */
-extern void Inode_ClearCache(int Handle);
-
-/**
- * \}
- */
-
-#endif
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