diff options
Diffstat (limited to 'lib/kernel/src/pg2.erl')
| -rw-r--r-- | lib/kernel/src/pg2.erl | 52 |
1 files changed, 28 insertions, 24 deletions
diff --git a/lib/kernel/src/pg2.erl b/lib/kernel/src/pg2.erl index 0d5838716e..edf4aedde2 100644 --- a/lib/kernel/src/pg2.erl +++ b/lib/kernel/src/pg2.erl @@ -1,18 +1,19 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 1997-2011. All Rights Reserved. +%% Copyright Ericsson AB 1997-2016. All Rights Reserved. %% -%% The contents of this file are subject to the Erlang Public License, -%% Version 1.1, (the "License"); you may not use this file except in -%% compliance with the License. You should have received a copy of the -%% Erlang Public License along with this software. If not, it can be -%% retrieved online at http://www.erlang.org/. +%% Licensed under the Apache License, Version 2.0 (the "License"); +%% you may not use this file except in compliance with the License. +%% You may obtain a copy of the License at %% -%% Software distributed under the License is distributed on an "AS IS" -%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See -%% the License for the specific language governing rights and limitations -%% under the License. +%% http://www.apache.org/licenses/LICENSE-2.0 +%% +%% Unless required by applicable law or agreed to in writing, software +%% distributed under the License is distributed on an "AS IS" BASIS, +%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +%% See the License for the specific language governing permissions and +%% limitations under the License. %% %% %CopyrightEnd% %% @@ -45,7 +46,7 @@ start() -> -spec create(Name :: name()) -> 'ok'. create(Name) -> - ensure_started(), + _ = ensure_started(), case ets:member(pg2_table, {group, Name}) of false -> global:trans({{?MODULE, Name}, self()}, @@ -60,7 +61,7 @@ create(Name) -> -spec delete(Name :: name()) -> 'ok'. delete(Name) -> - ensure_started(), + _ = ensure_started(), global:trans({{?MODULE, Name}, self()}, fun() -> gen_server:multi_call(?MODULE, {delete, Name}) @@ -71,7 +72,7 @@ delete(Name) -> when Name :: name(). join(Name, Pid) when is_pid(Pid) -> - ensure_started(), + _ = ensure_started(), case ets:member(pg2_table, {group, Name}) of false -> {error, {no_such_group, Name}}; @@ -88,7 +89,7 @@ join(Name, Pid) when is_pid(Pid) -> when Name :: name(). leave(Name, Pid) when is_pid(Pid) -> - ensure_started(), + _ = ensure_started(), case ets:member(pg2_table, {group, Name}) of false -> {error, {no_such_group, Name}}; @@ -105,7 +106,7 @@ leave(Name, Pid) when is_pid(Pid) -> when Name :: name(). get_members(Name) -> - ensure_started(), + _ = ensure_started(), case ets:member(pg2_table, {group, Name}) of true -> group_members(Name); @@ -117,7 +118,7 @@ get_members(Name) -> when Name :: name(). get_local_members(Name) -> - ensure_started(), + _ = ensure_started(), case ets:member(pg2_table, {group, Name}) of true -> local_group_members(Name); @@ -128,7 +129,7 @@ get_local_members(Name) -> -spec which_groups() -> [Name :: name()]. which_groups() -> - ensure_started(), + _ = ensure_started(), all_groups(). -spec get_closest_pid(Name) -> pid() | {'error', Reason} when @@ -140,32 +141,35 @@ get_closest_pid(Name) -> [Pid] -> Pid; [] -> - {_,_,X} = erlang:now(), case get_members(Name) of [] -> {error, {no_process, Name}}; Members -> - lists:nth((X rem length(Members))+1, Members) + random_element(Members) end; Members when is_list(Members) -> - {_,_,X} = erlang:now(), - lists:nth((X rem length(Members))+1, Members); + random_element(Members); Else -> Else end. +random_element(List) -> + X = abs(erlang:monotonic_time() + bxor erlang:unique_integer()), + lists:nth((X rem length(List)) + 1, List). + %%% %%% Callback functions from gen_server %%% -record(state, {}). --opaque state() :: #state{}. +-type state() :: #state{}. -spec init(Arg :: []) -> {'ok', state()}. init([]) -> Ns = nodes(), - net_kernel:monitor_nodes(true), + ok = net_kernel:monitor_nodes(true), lists:foreach(fun(N) -> {?MODULE, N} ! {new_pg2, node()}, self() ! {nodeup, N} @@ -283,7 +287,7 @@ member_died(Ref) -> join_group(Name, Pid) -> Ref_Pid = {ref, Pid}, - try _ = ets:update_counter(pg2_table, Ref_Pid, {4, +1}) + try _ = ets:update_counter(pg2_table, Ref_Pid, {4, +1}), true catch _:_ -> {RPid, Ref} = do_monitor(Pid), true = ets:insert(pg2_table, {Ref_Pid, RPid, Ref, 1}), |