67 lines
2.8 KiB
OCaml
67 lines
2.8 KiB
OCaml
(*****************************************************************************)
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(* *)
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(* Open Source License *)
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(* Copyright (c) 2018 Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
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(* *)
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(* Permission is hereby granted, free of charge, to any person obtaining a *)
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(* copy of this software and associated documentation files (the "Software"),*)
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(* to deal in the Software without restriction, including without limitation *)
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(* the rights to use, copy, modify, merge, publish, distribute, sublicense, *)
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(* and/or sell copies of the Software, and to permit persons to whom the *)
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(* Software is furnished to do so, subject to the following conditions: *)
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(* *)
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(* The above copyright notice and this permission notice shall be included *)
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(* in all copies or substantial portions of the Software. *)
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(* *)
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(* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*)
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(* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, *)
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(* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL *)
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(* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER*)
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(* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING *)
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(* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER *)
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(* DEALINGS IN THE SOFTWARE. *)
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(* *)
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(*****************************************************************************)
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type 'a inner_stopper = {
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id: int ;
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push: ('a option -> unit) ;
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mutable active : bool;
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input : 'a input;
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}
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and 'a input =
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{ mutable watchers : 'a inner_stopper list;
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mutable cpt : int; }
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type stopper = unit -> unit
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let create_input () =
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{ watchers = [];
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cpt = 0 }
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let create_fake_stream () =
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let str, push = Lwt_stream.create () in
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str, (fun () -> push None)
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let notify input info =
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List.iter (fun w -> w.push (Some info)) input.watchers
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let shutdown_output output =
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if output.active then begin
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output.active <- false;
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output.push None;
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output.input.watchers <-
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List.filter (fun w -> w.id <> output.id) output.input.watchers;
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end
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let create_stream input =
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input.cpt <- input.cpt + 1;
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let id = input.cpt in
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let stream, push = Lwt_stream.create () in
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let output = { id; push; input; active = true } in
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input.watchers <- output :: input.watchers;
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stream, (fun () -> shutdown_output output)
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let shutdown f = f ()
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