od: remove unused properties from InputDecoder

src/uu/od/src/input_decoder.rs

@@ -27,11 +27,6 @@ where
     /// The number of bytes in the buffer reserved for the peek data from `PeekRead`.
     reserved_peek_length: usize,
 
-    /// The number of (valid) bytes in the buffer.
-    used_normal_length: usize,
-    /// The number of peek bytes in the buffer.
-    used_peek_length: usize,
-
     /// Byte order used to read data from the buffer.
     byte_order: ByteOrder,
 }
@@ -51,8 +46,6 @@ impl<I> InputDecoder<'_, I> {
             input,
             data: bytes,
             reserved_peek_length: peek_length,
-            used_normal_length: 0,
-            used_peek_length: 0,
             byte_order,
         }
     }
@@ -65,17 +58,14 @@ where
     /// calls `peek_read` on the internal stream to (re)fill the buffer. Returns a
     /// `MemoryDecoder` providing access to the result or returns an i/o error.
     pub fn peek_read(&mut self) -> io::Result<MemoryDecoder<'_>> {
-        let (n, p) = self
-            .input
-            .peek_read(self.data.as_mut_slice(), self.reserved_peek_length)?;
-        self.used_normal_length = n;
-        self.used_peek_length = p;
-        Ok(MemoryDecoder {
-            data: &mut self.data,
-            used_normal_length: self.used_normal_length,
-            used_peek_length: self.used_peek_length,
-            byte_order: self.byte_order,
-        })
+        self.input
+            .peek_read(self.data.as_mut_slice(), self.reserved_peek_length)
+            .map(|(n, p)| MemoryDecoder {
+                data: &mut self.data,
+                used_normal_length: n,
+                used_peek_length: p,
+                byte_order: self.byte_order,
+            })
     }
 }