Source file helpers.ml

(*****************************************************************************)
(*                                                                           *)
(* Open Source License                                                       *)
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open Error_monad

module MakeRaw (H : sig
  type t

  val name : string

  val of_bytes_opt : Bytes.t -> t option

  val to_string : t -> string

  val of_string_opt : string -> t option
end) =
struct
  let of_bytes_exn s =
    match H.of_bytes_opt s with
    | None -> Format.kasprintf invalid_arg "of_bytes_exn (%s)" H.name
    | Some pk -> pk

  let of_bytes s =
    match H.of_bytes_opt s with
    | None -> error_with "of_bytes (%s)" H.name
    | Some pk -> Ok pk

  let of_string_exn s =
    match H.of_string_opt s with
    | None -> Format.kasprintf invalid_arg "of_string_exn (%s)" H.name
    | Some pk -> pk

  let of_string s =
    match H.of_string_opt s with
    | None -> error_with "of_string (%s)" H.name
    | Some pk -> Ok pk

  let to_hex s = Hex.of_string (H.to_string s)

  let of_hex_opt s = Option.bind (Hex.to_string s) H.of_string_opt

  let of_hex_exn s =
    match of_hex_opt s with
    | Some x -> x
    | None -> Format.kasprintf invalid_arg "of_hex_exn (%s)" H.name

  let of_hex s =
    match of_hex_opt s with
    | None -> error_with "of_hex (%s)" H.name
    | Some pk -> Ok pk
end

module MakeB58 (H : sig
  type t

  val name : string

  val b58check_encoding : t Base58.encoding
end) =
struct
  let of_b58check_opt s = Base58.simple_decode H.b58check_encoding s

  let of_b58check_exn s =
    match of_b58check_opt s with
    | Some x -> x
    | None -> Format.kasprintf Stdlib.failwith "Unexpected data (%s)" H.name

  let of_b58check s =
    match of_b58check_opt s with
    | Some x -> Ok x
    | None ->
        error_with "Failed to read a b58check_encoding data (%s): %S" H.name s

  let to_b58check s = Base58.simple_encode H.b58check_encoding s

  let to_short_b58check s =
    String.sub
      (to_b58check s)
      0
      (10 + String.length (Base58.prefix H.b58check_encoding))
end

module MakeEncoder (H : sig
  type t

  val title : string

  val name : string

  val to_b58check : t -> string

  val to_short_b58check : t -> string

  val of_b58check : string -> t tzresult

  val of_b58check_exn : string -> t

  val of_b58check_opt : string -> t option

  val raw_encoding : t Data_encoding.t
end) =
struct
  let pp ppf t = Format.pp_print_string ppf (H.to_b58check t)

  let pp_short ppf t = Format.pp_print_string ppf (H.to_short_b58check t)

  let encoding =
    let open Data_encoding in
    splitted
      ~binary:(obj1 (req H.name H.raw_encoding))
      ~json:
        (def H.name ~title:(H.title ^ " (Base58Check-encoded)")
        @@ conv
             H.to_b58check
             (Data_encoding.Json.wrap_error H.of_b58check_exn)
             string)

  let of_b58check = H.of_b58check

  let rpc_arg =
    Tezos_rpc.Arg.make
      ~name:H.name
      ~descr:(Format.asprintf "%s (Base58Check-encoded)" H.name)
      ~destruct:(fun s ->
        match H.of_b58check_opt s with
        | None ->
            Error
              (Format.asprintf
                 "failed to decode Base58Check-encoded data (%s): %S"
                 H.name
                 s)
        | Some v -> Ok v)
      ~construct:H.to_b58check
      ()
end

module MakeIterator (H : sig
  type t

  val encoding : t Data_encoding.t

  val compare : t -> t -> int

  val equal : t -> t -> bool

  val hash : t -> int

  (* [seeded_hash] is a seeded alternative to [hash] meant to be used to create
     seeded hashtables. Check {!Stdlib.Hashtbl.MakeSeeded} for details. *)
  val seeded_hash : int -> t -> int
end) =
struct
  module Set = struct
    include Set.Make (struct
      type t = H.t

      let compare = H.compare
    end)

    exception Found of elt

    let random_elt s =
      let n = Random.int (cardinal s) in
      try
        ignore
          (fold
             (fun x i ->
               if i = n then raise (Found x) ;
               i + 1)
             s
             0
            : int) ;
        assert false
      with Found x -> x

    let encoding =
      Data_encoding.conv
        elements
        (fun l -> List.fold_left (fun m x -> add x m) empty l)
        Data_encoding.(list H.encoding)
  end

  module Table = struct
    include Hashtbl.MakeSeeded (struct
      type t = H.t

      (* See [src/lib_base/tzPervasives.ml] for an explanation *)
      [@@@ocaml.warning "-32"]

      let hash = H.seeded_hash

      let seeded_hash = H.seeded_hash

      [@@@ocaml.warning "+32"]

      let equal = H.equal
    end)

    let encoding arg_encoding =
      Data_encoding.conv
        (fun h -> fold (fun k v l -> (k, v) :: l) h [])
        (fun l ->
          let h = create (List.length l) in
          List.iter (fun (k, v) -> add h k v) l ;
          h)
        Data_encoding.(list (tup2 H.encoding arg_encoding))
  end

  module Map = struct
    include Map.Make (struct
      type t = H.t

      let compare = H.compare
    end)

    let encoding arg_encoding =
      Data_encoding.conv
        bindings
        (fun l -> List.fold_left (fun m (k, v) -> add k v m) empty l)
        Data_encoding.(list (tup2 H.encoding arg_encoding))
  end

  module Error_table = struct
    include Tezos_error_monad.TzLwtreslib.Hashtbl.Make_es (H)
  end

  module WeakRingTable = struct
    let h_encoding = H.encoding

    include Aches.Vache.Map (Aches.Vache.FIFO_Sloppy) (Aches.Vache.Weak) (H)

    let encoding arg_encoding =
      let open Data_encoding in
      conv
        (fun h -> (capacity h, fold (fun k v l -> (k, v) :: l) h []))
        (fun (capacity, l) ->
          let h = create capacity in
          List.iter (fun (k, v) -> replace h k v) l ;
          h)
      @@ obj2
           (req "capacity" int31)
           (req "content" @@ list (tup2 h_encoding arg_encoding))
  end
end

module Make (H : sig
  type t

  val title : string

  val name : string

  val b58check_encoding : t Base58.encoding

  val raw_encoding : t Data_encoding.t

  val compare : t -> t -> int

  val equal : t -> t -> bool

  val hash : t -> int

  val seeded_hash : int -> t -> int
end) =
struct
  include MakeB58 (H)

  include MakeEncoder (struct
    include H

    let to_b58check = to_b58check

    let to_short_b58check = to_short_b58check

    let of_b58check = of_b58check

    let of_b58check_opt = of_b58check_opt

    let of_b58check_exn = of_b58check_exn
  end)

  include MakeIterator (struct
    include H

    let encoding = encoding
  end)
end