Source file version.ml

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type t =
  { major : int
  ; minor : int }

let v1_0 = { major = 1; minor = 0 }
let v1_1 = { major = 1; minor = 1 }

let to_buffer b t =
  Buffer.add_string b "HTTP/";
  Buffer.add_string b (string_of_int t.major);
  Buffer.add_char   b '.';
  Buffer.add_string b (string_of_int t.minor)

let compare x y =
  let c = compare x.major y.major in
  if c <> 0 then c else compare x.minor y.minor

let to_string t =
  match t with
  | { major = 1; minor = 0 } -> "HTTP/1.0"
  | { major = 1; minor = 1 } -> "HTTP/1.1"
  | _ ->
    let b = Buffer.create 8 in
    to_buffer b t;
    Buffer.contents b

let of_string = function
  | "HTTP/1.1" -> { major = 1; minor = 1 }
  | "HTTP/1.0" -> { major = 1; minor = 0 }
  | s ->
    try Scanf.sscanf s "HTTP/%d.%d" (fun major minor -> { major; minor })
    with _ -> raise (Failure "Version.of_string")

let pp_hum fmt t =
  Format.fprintf fmt "HTTP/%d.%d" t.major t.minor