Source file fitness_repr.ml

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(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com>     *)
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type error += Invalid_fitness (* `Permanent *)

let () =
  register_error_kind
    `Permanent
    ~id:"invalid_fitness"
    ~title:"Invalid fitness"
    ~description:"Fitness representation should be exactly 8 bytes long."
    ~pp:(fun ppf () -> Format.fprintf ppf "Invalid fitness")
    Data_encoding.empty
    (function Invalid_fitness -> Some () | _ -> None)
    (fun () -> Invalid_fitness)

let int64_to_bytes i =
  let b = Bytes.make 8 '0' in
  TzEndian.set_int64 b 0 i ;
  b

let int64_of_bytes b =
  if Compare.Int.(Bytes.length b <> 8) then error Invalid_fitness
  else ok (TzEndian.get_int64 b 0)

let from_int64 fitness =
  [Bytes.of_string Constants_repr.version_number; int64_to_bytes fitness]

let to_int64 = function
  | [version; fitness]
    when Compare.String.(
           Bytes.to_string version = Constants_repr.version_number) ->
      int64_of_bytes fitness
  | [version; _fitness (* ignored since higher version takes priority *)]
    when Compare.String.(
           Bytes.to_string version = Constants_repr.version_number_004) ->
      ok 0L
  | [] -> ok 0L
  | _ -> error Invalid_fitness