Kernel - Implementing select()

[tpg/acess2.git] / Kernel / include / vfs.h

diff --git a/Kernel/include/vfs.h b/Kernel/include/vfs.h
index e3a61d4..e37ebfe 100644 (file)
--- a/Kernel/include/vfs.h
+++ b/Kernel/include/vfs.h
@@ -21,6 +21,11 @@
 
 #include <acess.h>
 
+/**
+ * \brief Thread list datatype for VFS_Select
+ */
+typedef struct sVFS_SelectList tVFS_SelectList;
+
 /**
  * \name tVFS_Node Flags
  * \brief Flag values for tVFS_Node.Flags
@@ -67,7 +72,7 @@
  */
 
 /**
- * \brief VFS Node
+ * \brief 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.
@@ -99,10 +104,18 @@ typedef struct sVFS_Node
        Uint32  Flags;  //!< File Flags
        
        /**
-        * Pointer to cached data (FS Specific)
-        * \note Inode_* will free when the node is uncached this if needed
+        * \brief Pointer to cached data (FS Specific)
+        * \note The Inode_* functions will free when the node is uncached
+        *       this if needed
         */
        void    *Data;
+       
+       /**
+        * \brief Node mutex
+        * \note Provided for the Filesystem driver's use
+        */
+       tMutex  Lock;
+       
        /**
         * \}
         */
@@ -119,7 +132,7 @@ typedef struct sVFS_Node
         */
        
        /**
-        * \name Access controll
+        * \name Access control
         * \{
         */
        tUID    UID;    //!< ID of Owning User
@@ -131,6 +144,20 @@ typedef struct sVFS_Node
         * \}
         */
        
+       /**
+        * \name VFS_Select() fields
+        * \{
+        */
+        int    DataAvaliable;
+       tVFS_SelectList *ReadThreads;   //!< Threads waiting to read
+        int    BufferFull;
+       tVFS_SelectList *WriteThreads;  //!< Threads waiting to write
+        int    ErrorOccurred;
+       tVFS_SelectList *ErrorThreads;  //!< Threads waiting for an error
+       /**
+        * \}
+        */
+       
        /**
         * \name Common Functions
         * \brief Functions that are used no matter the value of .Flags
@@ -160,7 +187,7 @@ typedef struct sVFS_Node
         int    (*IOCtl)(struct sVFS_Node *Node, int Id, void *Data);
        
        /**
-        * }
+        * \}
         */
        
        /**
@@ -190,7 +217,7 @@ typedef struct sVFS_Node
        Uint64  (*Write)(struct sVFS_Node *Node, Uint64 Offset, Uint64 Length, void *Buffer);
        
        /**
-        * }
+        * \}
         */
        
        /**
@@ -205,7 +232,7 @@ typedef struct sVFS_Node
         * \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);
+       struct sVFS_Node        *(*FindDir)(struct sVFS_Node *Node, const char *Name);
        
        /**
         * \brief Read from a directory
@@ -224,9 +251,9 @@ typedef struct sVFS_Node
         * \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
+        * \return Zero on Success, non-zero on error (see errno.h)
         */
-        int    (*MkNod)(struct sVFS_Node *Node, char *Name, Uint Flags);
+        int    (*MkNod)(struct sVFS_Node *Node, const char *Name, Uint Flags);
        
        /**
         * \brief Relink (Rename/Remove) a file/directory
@@ -235,10 +262,19 @@ typedef struct sVFS_Node
         * \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);
+        int    (*Relink)(struct sVFS_Node *Node, const char *OldName, const char *NewName);
+       
+       /**
+        * \brief Link a node to a name
+        * \param Node  Pointer to this node (directory)
+        * \param Child Node to create a new link to
+        * \param NewName       Name for the new link
+        * \return Zeron on success, non-zero on error (see errno.h)
+        */
+        int    (*Link)(struct sVFS_Node *Node, struct sVFS_Node *Child, const char *NewName);
         
         /**
-         * }
+         * \}
          */
 } tVFS_Node;
 
@@ -248,12 +284,12 @@ typedef struct sVFS_Node
 typedef struct sVFS_Driver
 {
        //! \brief Unique Identifier for this filesystem type
-       char    *Name;
+       const char      *Name;
        //! \brief Flags applying to this driver
        Uint    Flags;
        
        //! \brief Callback to mount a device
-       tVFS_Node       *(*InitDevice)(char *Device, char **Options);
+       tVFS_Node       *(*InitDevice)(const char *Device, const char **Options);
        //! \brief Callback to unmount a device
        void    (*Unmount)(tVFS_Node *Node);
        //! \brief Used internally (next driver in the chain)
@@ -294,7 +330,7 @@ extern int  VFS_AddDriver(tVFS_Driver *Info);
  * \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);
+extern tVFS_Driver     *VFS_GetFSByName(const char *Name);
 /**
  * \fn tVFS_ACL *VFS_UnixToAcessACL(Uint Mode, Uint Owner, Uint Group)
  * \brief Transforms Unix Permssions into Acess ACLs
@@ -316,11 +352,11 @@ extern tVFS_ACL   *VFS_UnixToAcessACL(Uint Mode, Uint Owner, Uint Group);
  * \{
  */
 /**
- * \fn int Inode_GetHandle()
+ * \fn int Inode_GetHandle(void)
  * \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();
+extern int     Inode_GetHandle(void);
 /**
  * \fn tVFS_Node *Inode_GetCache(int Handle, Uint64 Inode)
  * \brief Gets an inode from the node cache