39 lines
1.2 KiB
Erlang
39 lines
1.2 KiB
Erlang
%% Copyright (c) 2013-2019 EMQ Technologies Co., Ltd. All Rights Reserved.
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%%
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%% Licensed under the Apache License, Version 2.0 (the "License");
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%% you may not use this file except in compliance with the License.
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%% You may obtain 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, software
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%% distributed under the License is distributed on an "AS IS" BASIS,
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%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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%% See the License for the specific language governing permissions and
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%% limitations under the License.
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%% @doc The utility functions for erlang process dictionary.
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-module(emqx_pd).
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-include("types.hrl").
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-export([ update_counter/2
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, get_counter/1
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, reset_counter/1
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]).
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-type(key() :: term()).
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-spec(update_counter(key(), number()) -> maybe(number())).
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update_counter(Key, Inc) ->
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put(Key, get_counter(Key) + Inc).
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-spec(get_counter(key()) -> number()).
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get_counter(Key) ->
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case get(Key) of undefined -> 0; Cnt -> Cnt end.
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-spec(reset_counter(key()) -> number()).
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reset_counter(Key) ->
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case put(Key, 0) of undefined -> 0; Cnt -> Cnt end.
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