74 lines
1.5 KiB
Erlang
74 lines
1.5 KiB
Erlang
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%% -------------------------------------------------------------------
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%%
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%% Machi: a small village of replicated files
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%%
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%% Copyright (c) 2014 Basho Technologies, Inc. All Rights Reserved.
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%%
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%% This file is provided to you under the Apache License,
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%% Version 2.0 (the "License"); you may not use this file
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%% except in compliance with the License. You may obtain
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%% a copy of the License at
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%%
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%% http://www.apache.org/licenses/LICENSE-2.0
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%%
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%% Unless required by applicable law or agreed to in writing,
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%% software distributed under the License is distributed on an
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%% "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
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%% KIND, either express or implied. See the License for the
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%% specific language governing permissions and limitations
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%% under the License.
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%%
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%% -------------------------------------------------------------------
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-module(lamport_clock).
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-export([init/0, reset/0, get/0, update/1, incr/0]).
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-define(KEY, ?MODULE).
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-ifdef(TEST).
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init() ->
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case get(?KEY) of
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undefined ->
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reset();
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N when is_integer(N) ->
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ok
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end.
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reset() ->
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FakeTOD = 0,
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put(?KEY, FakeTOD + 1).
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get() ->
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init(),
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get(?KEY).
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update(Remote) ->
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New = erlang:max(get(?KEY), Remote) + 1,
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put(?KEY, New),
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New.
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incr() ->
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New = get(?KEY) + 1,
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put(?KEY, New),
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New.
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-else. % TEST
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init() ->
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ok.
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reset() ->
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ok.
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get() ->
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ok.
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update(_) ->
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ok.
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incr() ->
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ok.
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-endif. % TEST
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