Source file `clock_drift.ml`

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(*****************************************************************************)
(* Open Source License                                                       *)
(* Copyright (c) 2020 Nomadic Labs, <contact@nomadic-labs.com>               *)
(*                                                                           *)
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(*                                                                           *)
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(* DEALINGS IN THE SOFTWARE.                                                 *)
(*                                                                           *)
(*****************************************************************************)

let max_timestamp_drift : Ptime.span = Ptime.Span.of_int_s 5

let soon : unit -> Time.Protocol.t =
 fun () ->
  let now = Time.System.now () in
  match Ptime.add_span now max_timestamp_drift with
  | Some s -> Time.System.to_protocol s
  | None -> invalid_arg "Clock_drift.is_not_too_far_in_the_future: end of time"

let is_not_too_far_in_the_future : Time.Protocol.t -> bool =
 fun timestamp -> Time.Protocol.compare (soon ()) timestamp >= 0