Cleanup, add node and header commands

src/header.rs

@@ -1,26 +1,44 @@
 use core::{mem, slice};
 use core::ops::{Deref, DerefMut};
 
-use super::Extent;
-
 /// The header of the filesystem
+#[derive(Debug)]
 #[repr(packed)]
 pub struct Header {
+    /// Signature, should be b"REDOXFS\0"
     pub signature: [u8; 8],
+    /// Version, should be 1
     pub version: u64,
-    pub free_space: Extent,
-    pub padding: [u8; 224],
-    pub extents: [Extent; 16],
+    /// Disk ID, a 128-byte unique identifier
+    pub uuid: [u8; 16],
+    /// Disk size, in 512-byte sectors
+    pub size: u64,
+    /// Block of root node
+    pub root: u64,
+    /// Block of free space node
+    pub free_space: u64,
 }
 
 impl Header {
-    pub fn new() -> Header {
+    pub fn default() -> Header {
         Header {
             signature: [0; 8],
             version: 0,
-            free_space: Extent::default(),
-            padding: [0; 224],
-            extents: [Extent::default(); 16]
+            uuid: [0; 16],
+            size: 0,
+            root: 0,
+            free_space: 0,
+        }
+    }
+
+    pub fn new() -> Header {
+        Header {
+            signature: *b"REDOXFS\0",
+            version: 1,
+            uuid: [0; 16],
+            size: 0,
+            root: 0,
+            free_space: 0,
         }
     }
 
@@ -45,3 +63,8 @@ impl DerefMut for Header {
         }
     }
 }
+
+#[test]
+fn header_size_test(){
+    assert!(mem::size_of::<Header>() <= 512);
+}