39 lines
869 B
Erlang
39 lines
869 B
Erlang
-module(elixir_counter).
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-export([start_link/0, init/1, handle_call/3, handle_cast/2,
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handle_info/2, terminate/2, code_change/3, next/0]).
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-behaviour(gen_server).
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-define(timeout, 30000). %% 30 seconds
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-define(limit, 4294967295). %% 2^32 - 1
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next() ->
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gen_server:call(?MODULE, next, ?timeout).
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start_link() ->
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gen_server:start_link({local, ?MODULE}, ?MODULE, 0, []).
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init(Counter) ->
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{ok, Counter}.
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handle_call(next, _From, Counter) ->
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{reply, Counter, bump(Counter)};
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handle_call(Request, _From, Counter) ->
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{stop, {badcall, Request}, Counter}.
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handle_cast(Request, Counter) ->
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{stop, {badcast, Request}, Counter}.
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handle_info(_Request, Counter) ->
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{noreply, Counter}.
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terminate(_Reason, _Counter) ->
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ok.
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code_change(_Old, Counter, _Extra) ->
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{ok, Counter}.
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bump(Counter) when Counter < ?limit ->
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Counter + 1;
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bump(_Counter) ->
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0.
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