Temp

Signed-off-by: Klimenty Tsoutsman <klim@tsoutsman.com>

kernel/vfs/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "vfs"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+path = { path = "../path" }
+memory = { path = "../memory" }
+spin = "0.9.1"

kernel/vfs/src/implementor.rs

@@ -0,0 +1,47 @@
+use alloc::boxed::Box;
+
+pub trait FileSystem {
+    type File: File;
+    type Directory: Directory<File = Self::File>;
+
+    fn root(&self) -> Self::Directory;
+
+    // fn to_dyn(self) -> Box<dyn FileSystem<File = dyn File<File = dyn File, Directory = dyn Directory>, Directory = dyn Directory>>;
+}
+
+static X: Box<dyn FileSystem<File = dyn File, Directory = dyn Directory<File = dyn File>>> =
+    todo!();
+
+pub trait Node {
+    // type Directory: Directory;
+    fn parent(&self);
+    fn name(&self) -> &str;
+    // fn as_type(&self) -> NodeType<Self::File, Self::Directory>;
+}
+
+pub enum NodeType<F, D>
+where
+    Self: ?Sized,
+{
+    File(F),
+    Directory(D),
+}
+
+pub trait Directory: Node {
+    type File: File;
+
+    fn create_dir(&self, name: &str);
+
+    fn create_file(&self, name: &str);
+
+    fn mount<T>(&self, file_system: T)
+    where
+        T: FileSystem;
+
+    fn get(&self, name: &str) -> NodeType<Self::File, Self>;
+}
+
+pub trait File: Node {
+    // TODO
+    fn read(&self);
+}

kernel/vfs/src/lib.rs

@@ -0,0 +1,16 @@
+// The tracking issue (#36887) has been open since 2016; I don't think it's
+// getting removed any time soon.
+#![allow(invalid_type_param_default)]
+#![feature(associated_type_defaults)]
+#![no_std]
+
+mod implementor;
+mod temp;
+
+extern crate alloc;
+
+use alloc::boxed::Box;
+
+struct FileSystem {
+    // inner: Box<dyn implementor::FileSystem>,
+}

kernel/vfs/src/temp.rs

@@ -0,0 +1,143 @@
+// #![no_std]
+//
+// extern crate alloc;
+//
+// use alloc::{string::String, sync::Arc, vec::Vec};
+// use memory::MappedPages;
+// use path::{Path, PathBuf};
+// use spin::Mutex;
+//
+// pub type NodeRef<Fs, Kind> = Arc<dyn Node<Fs, FileSystem = Fs, Kind = Kind>>;
+//
+// impl<T, Fs> Node<dyn FileSystem> for T
+// where
+//     T: Node<Fs>,
+// {
+//     type Kind = ();
+//
+//     fn name(&self) -> String {
+//         todo!()
+//     }
+//
+//     fn parent(&self) -> Option<NodeRef<Self::FileSystem, Directory>> {
+//         todo!()
+//     }
+//
+//     fn absolute_path(&self) -> PathBuf {
+//         todo!()
+//     }
+//
+//     fn as_specific(&self) -> SpecificNodeKind<Self::FileSystem> {
+//         todo!()
+//     }
+// }
+//
+// pub trait Node<T>
+// where
+//     T: FileSystem,
+// {
+//     type FileSystem: FileSystem = T;
+//
+//     type Kind: NodeKind;
+//
+//     fn name(&self) -> String;
+//
+//     fn parent(&self) -> Option<NodeRef<Self::FileSystem, Directory>>;
+//
+//     fn absolute_path(&self) -> PathBuf;
+//
+//     fn as_specific(&self) -> SpecificNodeKind<Self::FileSystem>;
+// }
+//
+// pub trait FileNode<T>: Node<T>
+// where
+//     T: FileSystem,
+// {
+//     fn as_mapping(&self) -> Result<&MappedPages, &'static str>;
+// }
+//
+// pub trait DirectoryNode<T>: Node<T>
+// where
+//     T: FileSystem,
+// {
+//     fn get<Kind = Any>(&self, path: &Path) -> Option<NodeRef<Self::FileSystem, Kind>>
+//     where
+//         Kind: NodeKind;
+//
+//     fn insert<Kind>(
+//         &mut self,
+//         node: NodeRef<Self::FileSystem, Kind>,
+//     ) -> Result<Option<NodeRef<Self::FileSystem, Kind>>, &'static str>
+//     where
+//         Kind: NodeKind;
+//
+//     fn remove<Kind>(
+//         &mut self,
+//         node: NodeRef<Self::FileSystem, Kind>,
+//     ) -> Option<NodeRef<Self::FileSystem, Kind>>
+//     where
+//         Kind: NodeKind;
+//
+//     fn list(&self) -> Vec<NodeRef<Self::FileSystem, Any>>;
+// }
+//
+// pub struct Any;
+// impl private::Sealed for Any {}
+//
+// impl NodeKind for Any {
+//     fn from_any<Fs>(node: NodeRef<Fs, Any>) -> Option<NodeRef<Fs, Self>>
+//     where
+//         Fs: FileSystem,
+//     {
+//         Some(node)
+//     }
+// }
+//
+// pub struct Directory;
+//
+// impl private::Sealed for Directory {}
+// impl NodeKind for Directory {
+//     fn from_any<Fs>(node: NodeRef<Fs, Any>) -> Option<NodeRef<Fs, Self>>
+//     where
+//         Fs: FileSystem,
+//     {
+//         match node.lock().as_specific() {
+//             SpecificNodeKind::Directory(d) => Some(d),
+//             _ => None,
+//         }
+//     }
+// }
+//
+// pub struct File;
+//
+// impl private::Sealed for File {}
+// impl NodeKind for File {
+//     fn from_any<Fs>(node: NodeRef<Fs, Any>) -> Option<NodeRef<Fs, Self>>
+//     where
+//         Fs: FileSystem,
+//     {
+//         match node.lock().as_specific() {
+//             SpecificNodeKind::File(f) => Some(f),
+//             _ => None,
+//         }
+//     }
+// }
+//
+// pub trait DirectoryGetKind: private::Sealed {}
+//
+// pub trait NodeKind: private::Sealed {
+//     fn from_any<Fs>(node: NodeRef<Fs, Any>) -> Option<NodeRef<Fs, Self>>
+//     where
+//         Fs: FileSystem;
+// }
+//
+// pub enum SpecificNodeKind<Fs> {
+//     File(NodeRef<Fs, File>),
+//     Directory(NodeRef<Fs, Directory>),
+// }
+//
+// pub trait FileSystem {}
+//
+// mod private {
+//     pub trait Sealed {}
+// }