parse the question

lib/response.ml

@@ -2,8 +2,32 @@ open Types
 open Utils
 
 let parse_header reader =
-  match List.init 6 (fun offset -> unpack_short_be reader (offset * 2)) with
+  let max_size = 6 in
+  match List.init max_size (fun offset -> unpack_short_be reader (offset * 2)) with
   | [ id; flags; num_questions; num_answers; num_authorities; num_additionals ] ->
-    { id; flags; num_questions; num_answers; num_authorities; num_additionals }
+    ( bytes_forward reader (max_size * 2)
+    , { id; flags; num_questions; num_answers; num_authorities; num_additionals } )
+  | _ -> failwith "Invalid number of fields"
+;;
+
+let decode_name_simple reader =
+  let rec read_parts parts pos =
+    let length = int_of_char (Bytes.get reader pos) in
+    if length = 0
+    then 1, parts
+    else (
+      let part = Bytes.sub_string reader (pos + 1) length in
+      let last_length, parts' = read_parts (parts @ [ part ]) (pos + 1 + length) in
+      last_length + length + 1, parts')
+  in
+  let offset, parts = read_parts [] 0 in
+  bytes_forward reader offset, String.concat "." parts
+;;
+
+let parse_question reader =
+  let reader', name_b = decode_name_simple reader in
+  let name = String.to_bytes name_b in
+  match List.init 2 (fun offset -> unpack_short_be reader' (offset * 2)) with
+  | [ type_; class_ ] -> { name; type_; class_ }
   | _ -> failwith "Invalid number of fields"
 ;;

lib/utils.ml

@@ -32,3 +32,5 @@ let unpack_short_be data offset =
   let lsb = int_of_char (Bytes.get data (offset + 1)) in
   (msb lsl 8) + lsb
 ;;
+
+let bytes_forward data offset = Bytes.sub data offset (Bytes.length data - offset)