Packages
ra
3.0.2
3.1.9
3.1.8
3.1.7
3.1.6
3.1.5
3.1.4
3.1.3
3.1.2
3.1.1
3.1.0
3.0.2
3.0.1
3.0.0
3.0.0-beta.1
2.17.3
2.17.2
2.17.1
2.17.0
2.16.13
2.16.12
2.16.11
2.16.10
2.16.9
2.16.8
2.16.7
2.16.6
2.16.5
2.16.4
2.16.3
2.16.2
2.16.1
2.16.0
2.16.0-pre.12
2.16.0-pre.11
2.16.0-pre.10
2.16.0-pre.9
2.16.0-pre.8
2.16.0-pre.7
2.16.0-pre.6
2.16.0-pre.5
2.16.0-pre.4
2.16.0-pre.3
2.16.0-pre.2
2.16.0-pre.1
2.15.4
2.15.3
2.15.2
2.15.1
2.15.0
2.14.0
2.13.6
2.13.5
2.13.4
2.13.3
2.13.2
2.13.1
2.13.0
2.13.0-pre.1
2.12.0
2.11.0
2.11.0-pre.1
2.10.2-pre.2
2.10.2-pre.1
2.10.1
2.10.0
2.10.0-pre.3
2.10.0-pre.2
2.10.0-pre.1
2.9.10-pre.1
2.9.1
2.9.1-pre.2
2.9.1-pre.1
2.9.0
2.8.0
retired
2.7.3
2.7.2
2.7.1
2.7.0
2.7.0-pre.3
2.7.0-pre.2
2.7.0-pre.1
2.6.3
2.6.2
2.6.1
2.6.0-pre.1
2.5.1
2.5.1-pre.1
2.5.0
2.4.9
2.4.8
2.4.7
2.4.6
2.4.5
2.4.4
2.4.3
2.4.2
retired
2.4.1
2.4.0
2.3.0
2.2.0
2.1.0
2.0.13
2.0.12
2.0.11
2.0.10
2.0.9
2.0.8
2.0.7
2.0.6
2.0.5
2.0.4
2.0.3
2.0.2
2.0.1
2.0.0
1.1.9
1.1.8
1.1.7
1.1.6
1.1.5
1.1.4
1.1.3
1.1.2
1.1.1
1.1.0
1.0.8
1.0.7
1.0.6
1.0.5
1.0.4
1.0.3
1.0.2
1.0.1
1.0.0
0.9.6
0.9.5
0.9.4
0.9.2
0.3.3
retired
0.3.2
retired
0.3.1
retired
Raft library
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Files
src/ra_ets_queue.erl
%% This Source Code Form is subject to the terms of the Mozilla Public
%% License, v. 2.0. If a copy of the MPL was not distributed with this
%% file, You can obtain one at https://mozilla.org/MPL/2.0/.
%%
%% Copyright (c) 2017-2025 Broadcom. All Rights Reserved. The term Broadcom refers to Broadcom Inc. and/or its subsidiaries.
%% @hidden
-module(ra_ets_queue).
-export([
new/0,
in/2,
reset/1,
take/2,
len/1
]).
-record(?MODULE, {tbl :: ets:tid(),
next_key = 0 :: non_neg_integer(),
len = 0 :: non_neg_integer(),
queue = queue:new() :: queue:queue()}).
-opaque state() :: #?MODULE{}.
-type item() :: term().
-export_type([
state/0
]).
-spec new() -> state().
new() ->
Tid = ets:new(?MODULE, [ordered_set, private]),
#?MODULE{tbl = Tid}.
-spec in(item(), state()) -> state().
in(Item, #?MODULE{tbl = Tbl,
queue = Q,
len = Len,
next_key = NextKey} = State) ->
true = ets:insert(Tbl, {NextKey, Item}),
State#?MODULE{next_key = NextKey + 1,
len = Len + 1,
queue = queue:in(NextKey, Q)}.
-spec len(state()) -> non_neg_integer().
len(#?MODULE{len = Len}) ->
Len.
-spec reset(state()) -> state().
reset(#?MODULE{tbl = Tbl}) ->
true = ets:delete_all_objects(Tbl),
#?MODULE{tbl = Tbl,
len = 0,
queue = queue:new()}.
-spec take(non_neg_integer(), state()) ->
{[item()], state()}.
take(Num, #?MODULE{tbl = Tbl,
len = Len,
queue = Q0} = State) ->
{Q, Taken, Out} = queue_take(Num, Q0, Tbl),
{Out, State#?MODULE{len = Len - Taken,
queue = Q}}.
%% Internal
queue_take(N, Q, Tbl) ->
queue_take(N, Q, Tbl, 0, []).
queue_take(0, Q, _Tbl, Taken, Acc) ->
{Q, Taken, lists:reverse(Acc)};
queue_take(N, Q0, Tbl, Taken, Acc) ->
case queue:out(Q0) of
{{value, Key}, Q} ->
[{Key, I}] = ets:take(Tbl, Key),
queue_take(N - 1, Q, Tbl, Taken + 1,
[I | Acc]);
{empty, _} ->
{Q0, Taken, lists:reverse(Acc)}
end.