Method rename

api/src/vfs/tmp.rs:428–451

TODO: atomicity

(&self, src_name: &str, dst_dir: &DirNode, dst_name: &str)

    // TODO: atomicity
    fn rename(&self, src_name: &str, dst_dir: &DirNode, dst_name: &str) -> VfsResult<()> {
        let dst_node = dst_dir.downcast::<Self>()?;
        if let Ok(entry) = dst_dir.lookup(dst_name) {
            let src_entry = self.lookup(src_name)?;
            if entry.inode() == src_entry.inode() {
                return Ok(());
            }
        }

        let src_entry = self
            .inode
            .as_dir()?
            .entries
            .lock()
            .remove(src_name)
            .ok_or(VfsError::NotFound)?;
        dst_node
            .inode
            .as_dir()?
            .entries
            .lock()
            .insert(dst_name.into(), src_entry);
        Ok(())
    }
}

impl Drop for MemoryNode {