Implement new file device interface

This is a complete redesign of the file device. The most notable
addition is the ability to ascend and descend the file tree.

1 files changed, 30 insertions, 0 deletions

diff --git a/src/devices/file/directory_entry.rs b/src/devices/file/directory_entry.rs
new file mode 100644
index 0000000..45de817
--- /dev/null
+++ b/src/devices/file/directory_entry.rs
@@ -0,0 +1,30 @@
+use crate::*;
+
+use std::cmp::Ordering;
+
+#[derive(PartialEq, Eq)]
+pub struct DirectoryChild {
+    pub byte_path: Vec<u8>,
+    pub entry_type: EntryType,
+}
+
+impl PartialOrd for DirectoryChild {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        let entry_type_ord = self.entry_type.cmp(&other.entry_type);
+        let final_order = match entry_type_ord {
+            Ordering::Equal => self.byte_path.cmp(&other.byte_path),
+            _ => entry_type_ord,
+        };
+        Some(final_order)
+    }
+}
+
+impl Ord for DirectoryChild {
+    fn cmp(&self, other: &Self) -> Ordering {
+        let entry_type_ord = self.entry_type.cmp(&other.entry_type);
+        match entry_type_ord {
+            Ordering::Equal => self.byte_path.cmp(&other.byte_path),
+            _ => entry_type_ord,
+        }
+    }
+}