Add stub read_dir for root

Cargo.lock

@@ -1,6 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "atomic-polyfill"
@@ -50,6 +50,14 @@ version = "1.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f64009896348fc5af4222e9cf7d7d82a95a256c634ebcf61c53e4ea461422242"
 
+[[package]]
+name = "dir_rpc"
+version = "0.1.0"
+dependencies = [
+ "parking_lot",
+ "postcard",
+]
+
 [[package]]
 name = "embedded-io"
 version = "0.4.0"
@@ -302,6 +310,7 @@ dependencies = [
 name = "tarfs"
 version = "0.1.0"
 dependencies = [
+ "dir_rpc",
  "file_rpc",
  "fs_rpc",
  "parking_lot",

Cargo.toml

@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+dir_rpc = { version = "0.1.0", path = "../dir_rpc" }
 file_rpc = { version = "0.1.0", path = "../file_rpc" }
 fs_rpc = { version = "0.1.0", path = "../fs_rpc" }
 parking_lot = "0.12.3"

src/main.rs

@@ -57,7 +57,10 @@ impl fs_rpc::Server for Serv {
         Ok((None, (self.files.read().len() - 1) as u64))
     }
 
-    fn open_dir(&self, _path: &std::path::Path, _mount_id: u64) -> Result<(Option<u64>, u64), Errno> {
+    fn open_dir(&self, path: &std::path::Path, _mount_id: u64) -> Result<(Option<u64>, u64), Errno> {
+        if path.to_str() == Some("") {
+            return Ok((None, 0)); // needed so chdir succeeds
+        }
         // TODO
         Err(Errno::ENOSYS)
     }
@@ -131,12 +134,24 @@ impl file_rpc::Server for Serv {
 
 }
 
+impl dir_rpc::Server for Serv {
+    fn next_entry(&self, _fd: u64) -> Result<Option<String>, Errno> {
+        // TODO
+        Err(Errno::ENOSYS)
+    }
+
+    fn close(&self, _fd: u64) -> Result<(), Errno> {
+        Ok(())
+    }
+}
+
 fn main() {
     let serv = Serv {
         mounts: Arc::new(RwLock::new(Vec::new())),
         files: Arc::new(RwLock::new(Vec::new())),
     };
     fs_rpc::register_server(Box::new(serv.clone()));
+    dir_rpc::register_server(Box::new(serv.clone()));
     file_rpc::register_server(Box::new(serv));
     let vfs_pid;
     loop {