Ext2: read_dir implementation

ableos/src/filesystem/errors.rs

@@ -5,10 +5,11 @@
  */
 
 pub enum FsError {
+    EndOfFile,
     InodeNotFound,
     InvalidDevice,
     IsDirectory,
-    EndOfFile,
+    NotADirectory,
     UnsupportedOperation,
 }
 
@@ -28,7 +29,7 @@ impl Into<FsError> for ext2::error::Error {
                 by_inodes: _,
             } => todo!(),
             ext2::error::Error::InodeNotFound { inode: _ } => FsError::InodeNotFound,
-            ext2::error::Error::NotADirectory { inode: _, name: _ } => todo!(),
+            ext2::error::Error::NotADirectory { inode: _, name: _ } => FsError::NotADirectory,
             ext2::error::Error::NotAbsolute { name: _ } => todo!(),
             ext2::error::Error::NotFound { name: _ } => todo!(),
         }

ableos/src/filesystem/ext2.rs

@@ -57,8 +57,17 @@ where
         todo!()
     }
 
-    fn read_dir(&self, _node: &FsNode, _index: usize) -> Result<DirectoryEntry> {
-        todo!()
+    fn read_dir(&self, node: &FsNode, index: usize) -> Result<DirectoryEntry> {
+        let inode = self
+            .fs
+            .inode_nth(node.inode as usize)
+            .ok_or_else(|| FsError::InodeNotFound)?;
+        let mut dir = inode.directory().ok_or_else(|| FsError::NotADirectory)?;
+        let entry = dir.nth(index)
+            .ok_or_else(|| FsError::InodeNotFound)?
+            .map_err(|e| e.into())?;
+
+        Ok(DirectoryEntry::new(entry.file_name_string(), entry.inode))
     }
 
     fn find_dir(&self, _node: &FsNode, _name: &str) -> Result<FsNode> {

ableos/src/filesystem/mod.rs

@@ -156,3 +156,12 @@ pub struct DirectoryEntry {
     name: String,
     inode: usize,
 }
+
+impl DirectoryEntry {
+    fn new(name: String, inode: usize) -> Self {
+        Self {
+            name,
+            inode,
+        }
+    }
+}