[Teton] Add ls and cd commands to rust impl.

rust/lib/victoriafalls/src/dir.rs

@@ -0,0 +1,27 @@
+use alloc::{
+    string::{String, ToString as _},
+    vec::Vec,
+};
+use mammoth::zion::ZError;
+
+pub fn exists(path: &str) -> Result<bool, ZError> {
+    let vfs = crate::get_client();
+    let result = vfs.get_directory(&crate::GetDirectoryRequest {
+        path: path.to_string(),
+    });
+
+    match result {
+        Ok(_) => Ok(true),
+        Err(ZError::NOT_FOUND) => Ok(false),
+        Err(e) => Err(e),
+    }
+}
+
+pub fn ls(path: &str) -> Result<Vec<String>, ZError> {
+    let vfs = crate::get_client();
+    let result = vfs.get_directory(&crate::GetDirectoryRequest {
+        path: path.to_string(),
+    })?;
+
+    Ok(result.filenames.split(',').map(|s| s.to_string()).collect())
+}

rust/lib/victoriafalls/src/file.rs

@@ -1,32 +1,14 @@
 use crate::OpenFileRequest;
-use crate::VFSClient;
 use alloc::string::ToString;
 use mammoth::zion::ZError;
 
-static mut VFS_CLIENT: Option<VFSClient> = None;
-
-fn get_client() -> &'static mut VFSClient {
-    unsafe {
-        if let None = VFS_CLIENT {
-            let endpoint_cap = yellowstone::from_init_endpoint()
-                .get_endpoint(&yellowstone::GetEndpointRequest {
-                    endpoint_name: "victoriafalls".to_string(),
-                })
-                .expect("Failed to get VFS endpoint");
-
-            VFS_CLIENT = Some(VFSClient::new(endpoint_cap.endpoint));
-        }
-        VFS_CLIENT.as_mut().unwrap()
-    }
-}
-
 pub struct File {
     memory: mammoth::mem::MemoryRegion,
 }
 
 impl File {
     pub fn open(path: &str) -> Result<Self, ZError> {
-        let vfs = get_client();
+        let vfs = crate::get_client();
         let resp = vfs.open_file(&OpenFileRequest {
             path: path.to_string(),
         })?;

rust/lib/victoriafalls/src/lib.rs

@@ -4,4 +4,22 @@ use core::include;
 
 include!(concat!(env!("OUT_DIR"), "/yunq.rs"));
 
+pub mod dir;
 pub mod file;
+
+static mut VFS_CLIENT: Option<VFSClient> = None;
+
+fn get_client() -> &'static mut VFSClient {
+    unsafe {
+        if let None = VFS_CLIENT {
+            let endpoint_cap = yellowstone::from_init_endpoint()
+                .get_endpoint(&yellowstone::GetEndpointRequest {
+                    endpoint_name: "victoriafalls".to_string(),
+                })
+                .expect("Failed to get VFS endpoint");
+
+            VFS_CLIENT = Some(VFSClient::new(endpoint_cap.endpoint));
+        }
+        VFS_CLIENT.as_mut().unwrap()
+    }
+}