%-*-Mode:erlang;coding:utf-8;tab-width:4;c-basic-offset:4;indent-tabs-mode:()-*- % ex: set ft=erlang fenc=utf-8 sts=4 ts=4 sw=4 et nomod: %%% %%%------------------------------------------------------------------------ %%% @doc %%% ==CPG Data Group Lookups.== %%% All functions in this module are for using cached cpg data without %%% sending messages to the cpg scope process. Using this module for %%% cpg group lookups is equivalent to the lazy destination refresh %%% methods in CloudI. %%% @end %%% %%% MIT License %%% %%% Copyright (c) 2011-2020 Michael Truog %%% %%% Permission is hereby granted, free of charge, to any person obtaining a %%% copy of this software and associated documentation files (the "Software"), %%% to deal in the Software without restriction, including without limitation %%% the rights to use, copy, modify, merge, publish, distribute, sublicense, %%% and/or sell copies of the Software, and to permit persons to whom the %%% Software is furnished to do so, subject to the following conditions: %%% %%% The above copyright notice and this permission notice shall be included in %%% all copies or substantial portions of the Software. %%% %%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR %%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, %%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE %%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER %%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING %%% FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER %%% DEALINGS IN THE SOFTWARE. %%% %%% @author Michael Truog %%% @copyright 2011-2020 Michael Truog %%% @version 1.8.1 {@date} {@time} %%%------------------------------------------------------------------------ -module(cpg_data). -author('mjtruog at protonmail dot com'). -export([get_groups/0, get_groups/1, get_groups/2, get_groups/3, get_empty_groups/0, get_members/2, get_members/3, get_local_members/2, get_local_members/3, get_remote_members/2, get_remote_members/3, which_groups/1, get_closest_pid/2, get_closest_pid/3, get_furthest_pid/2, get_furthest_pid/3, get_random_pid/2, get_random_pid/3, get_local_pid/2, get_local_pid/3, get_remote_pid/2, get_remote_pid/3, get_oldest_pid/2, get_oldest_pid/3, get_local_oldest_pid/2, get_local_oldest_pid/3, get_remote_oldest_pid/2, get_remote_oldest_pid/3, get_newest_pid/2, get_newest_pid/3, get_local_newest_pid/2, get_local_newest_pid/3, get_remote_newest_pid/2, get_remote_newest_pid/3]). -include("cpg_data.hrl"). -include("cpg_constants.hrl"). % GroupsData == GroupName -> #cpg_data{} lookup, using the DictI module -type state() :: {DictI :: module(), GroupsData :: any()}. -export_type([state/0]). -type get_members_return() :: {ok, cpg:name(), nonempty_list(pid())} | {error, {no_such_group, cpg:name()}}. -type get_pid_error_reason() :: {no_process, cpg:name()} | {no_such_group, cpg:name()}. -export_type([get_members_return/0, get_pid_error_reason/0]). %%%------------------------------------------------------------------------ %%% External interface functions %%%------------------------------------------------------------------------ %%------------------------------------------------------------------------- %% @doc %% ===Get the group storage.=== %% This provides the internal representation of process groups so that %% requests will not be blocked by the single process managing the scope %% of the process groups. %% @end %%------------------------------------------------------------------------- -spec get_groups() -> state(). get_groups() -> gen_server:call(?DEFAULT_SCOPE, cpg_data). %%------------------------------------------------------------------------- %% @doc %% ===Get the group storage for a particular scope or after a period of time.=== %% This provides the internal representation of process groups so that %% requests will not be blocked by the single process managing the scope %% of the process groups. %% @end %%------------------------------------------------------------------------- -spec get_groups(atom() | non_neg_integer()) -> state() | reference(). get_groups(Scope) when is_atom(Scope) -> gen_server:call(Scope, cpg_data); % send the groups as {cpg_data, Groups} after Time milliseconds to self() get_groups(Time) when is_integer(Time) -> erlang:send_after(Time, ?DEFAULT_SCOPE, {cpg_data, self()}). %%------------------------------------------------------------------------- %% @doc %% ===Get the group storage for a particular scope after a period of time.=== %% This provides the internal representation of process groups so that %% requests will not be blocked by the single process managing the scope %% of the process groups. %% @end %%------------------------------------------------------------------------- -spec get_groups(Scope :: atom(), Time :: non_neg_integer()) -> reference(). get_groups(Scope, Time) when is_atom(Scope), is_integer(Time) -> erlang:send_after(Time, Scope, {cpg_data, self()}). %%------------------------------------------------------------------------- %% @doc %% ===Get the group storage for a particular scope and destination after a period of time.=== %% This provides the internal representation of process groups so that %% requests will not be blocked by the single process managing the scope %% of the process groups. %% @end %%------------------------------------------------------------------------- -spec get_groups(Scope :: atom(), Destination :: pid() | atom(), Time :: non_neg_integer()) -> reference(). get_groups(Scope, Destination, Time) when is_atom(Scope), (is_pid(Destination) orelse is_atom(Destination)), is_integer(Time) -> erlang:send_after(Time, Scope, {cpg_data, Destination}). %%------------------------------------------------------------------------- %% @doc %% ===Get empty group storage.=== %% @end %%------------------------------------------------------------------------- -spec get_empty_groups() -> state(). get_empty_groups() -> DictI = cpg_app:group_storage(), {DictI, DictI:new()}. %%------------------------------------------------------------------------- %% @doc %% ===Get the members of a specific group.=== %% All members are ordered from newest to oldest, based on the group %% membership surviving netsplits (join order, not pid creation time). %% @end %%------------------------------------------------------------------------- -spec get_members(GroupName :: cpg:name(), Groups :: state()) -> get_members_return(). get_members(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> {ok, Pattern, History} end. %%------------------------------------------------------------------------- %% @doc %% ===Get the members of a specific group while excluding a specific pid.=== %% All members are ordered from newest to oldest, based on the group %% membership surviving netsplits (join order, not pid creation time). %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_members(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> get_members_return(). get_members(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> Members = [Pid || Pid <- History, Pid =/= Exclude], if Members == [] -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; true -> {ok, Pattern, Members} end end. %%------------------------------------------------------------------------- %% @doc %% ===Get only the local members of a specific group.=== %% All members are ordered from newest to oldest, based on the %% join order, not pid creation time. %% @end %%------------------------------------------------------------------------- -spec get_local_members(GroupName :: cpg:name(), Groups :: state()) -> get_members_return(). get_local_members(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{local_count = 0}} -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; {ok, Pattern, #cpg_data{local = Local}} -> {ok, Pattern, Local} end. %%------------------------------------------------------------------------- %% @doc %% ===Get only the local members of a specific group while excluding a specific pid.=== %% All members are ordered from newest to oldest, based on the %% join order, not pid creation time. %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_local_members(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> get_members_return(). get_local_members(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{local_count = 0}} -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; {ok, Pattern, #cpg_data{local = Local}} -> Members = [Pid || Pid <- Local, Pid =/= Exclude], if Members == [] -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; true -> {ok, Pattern, Members} end end. %%------------------------------------------------------------------------- %% @doc %% ===Get only the remote members of a specific group.=== %% All members are ordered from newest to oldest, based on the group %% membership surviving netsplits (join order, not pid creation time). %% @end %%------------------------------------------------------------------------- -spec get_remote_members(GroupName :: cpg:name(), Groups :: state()) -> get_members_return(). get_remote_members(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{remote_count = 0}} -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; {ok, Pattern, #cpg_data{remote = Remote}} -> {ok, Pattern, Remote} end. %%------------------------------------------------------------------------- %% @doc %% ===Get only the remote members of a specific group while excluding a specific pid.=== %% All members are ordered from newest to oldest, based on the group %% membership surviving netsplits (join order, not pid creation time). %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_remote_members(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> get_members_return(). get_remote_members(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{remote_count = 0}} -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; {ok, Pattern, #cpg_data{remote = Remote}} -> Members = [Pid || Pid <- Remote, Pid =/= Exclude], if Members == [] -> % to keep return values consistent with pg2 {error, {'no_such_group', GroupName}}; true -> {ok, Pattern, Members} end end. %%------------------------------------------------------------------------- %% @doc %% ===Get all the groups currently defined.=== %% @end %%------------------------------------------------------------------------- -spec which_groups(state()) -> list(cpg:name()). which_groups({DictI, GroupsData}) -> DictI:fetch_keys(GroupsData). %%------------------------------------------------------------------------- %% @doc %% ===Get a group member, with local pids given priority.=== %% @end %%------------------------------------------------------------------------- -spec get_closest_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_closest_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{local_count = 0, remote_count = RemoteCount, remote = Remote}} -> pick(RemoteCount, Remote, Pattern); {ok, Pattern, #cpg_data{local_count = LocalCount, local = Local}} -> pick(LocalCount, Local, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a group member, with local pids given priority while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_closest_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_closest_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{local_count = 0, remote_count = RemoteCount, remote = Remote}} -> pick(RemoteCount, Remote, Exclude, GroupName, Pattern); {ok, Pattern, #cpg_data{local_count = LocalCount, local = Local, remote_count = RemoteCount, remote = Remote}} -> pick(LocalCount, Local, RemoteCount, Remote, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a group member, with remote pids given priority.=== %% @end %%------------------------------------------------------------------------- -spec get_furthest_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_furthest_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{remote_count = 0, local_count = LocalCount, local = Local}} -> pick(LocalCount, Local, Pattern); {ok, Pattern, #cpg_data{remote_count = RemoteCount, remote = Remote}} -> pick(RemoteCount, Remote, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a group member, with remote pids given priority while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_furthest_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_furthest_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{remote_count = 0, local_count = LocalCount, local = Local}} -> pick(LocalCount, Local, Exclude, GroupName, Pattern); {ok, Pattern, #cpg_data{remote_count = RemoteCount, remote = Remote, local_count = LocalCount, local = Local}} -> pick(RemoteCount, Remote, LocalCount, Local, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a group member.=== %% @end %%------------------------------------------------------------------------- -spec get_random_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_random_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{local_count = LocalCount, remote_count = RemoteCount, history = History}} -> pick(LocalCount + RemoteCount, History, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_random_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_random_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{local_count = LocalCount, remote_count = RemoteCount, history = History}} -> pick(LocalCount + RemoteCount, History, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a local group member.=== %% @end %%------------------------------------------------------------------------- -spec get_local_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_local_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{local_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{local_count = LocalCount, local = Local}} -> pick(LocalCount, Local, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a local group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_local_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_local_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{local_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{local_count = LocalCount, local = Local}} -> pick(LocalCount, Local, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a remote group member.=== %% @end %%------------------------------------------------------------------------- -spec get_remote_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_remote_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{remote_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{remote_count = RemoteCount, remote = Remote}} -> pick(RemoteCount, Remote, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get a remote group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_remote_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_remote_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{remote_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{remote_count = RemoteCount, remote = Remote}} -> pick(RemoteCount, Remote, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the oldest group member.=== %% @end %%------------------------------------------------------------------------- -spec get_oldest_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_oldest_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_oldest(History, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the oldest group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_oldest_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_oldest_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_oldest(History, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the oldest local group member.=== %% @end %%------------------------------------------------------------------------- -spec get_local_oldest_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_local_oldest_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{local_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_local_oldest(History, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the oldest local group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_local_oldest_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_local_oldest_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{local_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_local_oldest(History, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the oldest remote group member.=== %% @end %%------------------------------------------------------------------------- -spec get_remote_oldest_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_remote_oldest_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{remote_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_remote_oldest(History, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the oldest remote group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_remote_oldest_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_remote_oldest_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{remote_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_remote_oldest(History, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the newest group member.=== %% @end %%------------------------------------------------------------------------- -spec get_newest_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_newest_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_newest(History, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the newest group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_newest_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_newest_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{history = []}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_newest(History, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the newest local group member.=== %% @end %%------------------------------------------------------------------------- -spec get_local_newest_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_local_newest_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{local_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_local_newest(History, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the newest local group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_local_newest_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_local_newest_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{local_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_local_newest(History, Exclude, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the newest remote group member.=== %% @end %%------------------------------------------------------------------------- -spec get_remote_newest_pid(GroupName :: cpg:name(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_remote_newest_pid(GroupName, Groups) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{remote_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_remote_newest(History, GroupName, Pattern) end. %%------------------------------------------------------------------------- %% @doc %% ===Get the newest remote group member while excluding a specific pid.=== %% Usually the self() pid is excluded with this function call. %% @end %%------------------------------------------------------------------------- -spec get_remote_newest_pid(GroupName :: cpg:name(), Exclude :: pid(), Groups :: state()) -> {ok, cpg:name(), pid()} | {error, get_pid_error_reason()}. get_remote_newest_pid(GroupName, Exclude, Groups) when is_pid(Exclude) -> case group_find(GroupName, Groups) of error -> {error, {'no_such_group', GroupName}}; {ok, _, #cpg_data{remote_count = 0}} -> {error, {'no_process', GroupName}}; {ok, Pattern, #cpg_data{history = History}} -> history_remote_newest(History, Exclude, GroupName, Pattern) end. %%%------------------------------------------------------------------------ %%% Private functions %%%------------------------------------------------------------------------ % should names be matched with "*" and "?" interpreted as wildcard characters % within the trie holding the groups of processes % matching with patterns group_find(GroupName, {trie, GroupsData}) -> try trie:find_match2(GroupName, GroupsData) catch exit:badarg -> error end; % matching without patterns group_find(GroupName, {DictI, GroupsData}) -> case DictI:find(GroupName, GroupsData) of {ok, Value} -> {ok, GroupName, Value}; error -> error end. pick(1, [Pid], Pattern) -> {ok, Pattern, Pid}; pick(N, L, Pattern) -> Pid = lists:nth(random(N), L), {ok, Pattern, Pid}. pick_i(I, I, _, [], [], _, GroupName, _) -> {error, {'no_process', GroupName}}; pick_i(I, I, 1, [Pid], [], _, _, Pattern) -> {ok, Pattern, Pid}; pick_i(I, I, Length, Filtered, [], _, _, Pattern) -> {ok, Pattern, lists:nth((I rem Length) + 1, Filtered)}; pick_i(I, I, Length, Filtered, [Exclude | L], Exclude, GroupName, Pattern) -> pick_i(I, I, Length, Filtered, L, Exclude, GroupName, Pattern); pick_i(I, I, _, _, [Pid | _], _, _, Pattern) -> {ok, Pattern, Pid}; pick_i(I, Random, Length, Filtered, [Exclude | L], Exclude, GroupName, Pattern) -> pick_i(I + 1, Random, Length, Filtered, L, Exclude, GroupName, Pattern); pick_i(I, Random, Length, Filtered, [Pid | L], Exclude, GroupName, Pattern) -> pick_i(I + 1, Random, Length + 1, [Pid | Filtered], L, Exclude, GroupName, Pattern). pick(0, [], _, GroupName, _) -> {error, {'no_process', GroupName}}; pick(N, L, Exclude, GroupName, Pattern) -> pick_i(1, random(N), 0, [], L, Exclude, GroupName, Pattern). pick(0, [], N2, L2, Exclude, GroupName, Pattern) -> pick(N2, L2, Exclude, GroupName, Pattern); pick(N1, L1, N2, L2, Exclude, GroupName, Pattern) -> case pick(N1, L1, Exclude, GroupName, Pattern) of {error, _} -> pick(N2, L2, Exclude, GroupName, Pattern); {ok, _, _} = Success -> Success end. history_oldest([_ | _] = History, Pattern) -> [Pid | _] = lists:reverse(History), {ok, Pattern, Pid}. history_oldest_pid([], _, GroupName, _) -> {error, {'no_process', GroupName}}; history_oldest_pid([Exclude | History], Exclude, GroupName, Pattern) -> history_oldest_pid(History, Exclude, GroupName, Pattern); history_oldest_pid([Pid | _], _, _, Pattern) -> {ok, Pattern, Pid}. history_oldest([_ | _] = History, Exclude, GroupName, Pattern) -> history_oldest_pid(lists:reverse(History), Exclude, GroupName, Pattern). history_local_oldest_pid([], _, GroupName, _) -> {error, {'no_process', GroupName}}; history_local_oldest_pid([Pid | _], Node, _, Pattern) when node(Pid) =:= Node -> {ok, Pattern, Pid}; history_local_oldest_pid([_ | History], Node, GroupName, Pattern) -> history_local_oldest_pid(History, Node, GroupName, Pattern). history_local_oldest([_ | _] = History, GroupName, Pattern) -> history_local_oldest_pid(lists:reverse(History), node(), GroupName, Pattern). history_local_oldest_pid([], _, _, GroupName, _) -> {error, {'no_process', GroupName}}; history_local_oldest_pid([Exclude | History], Exclude, Node, GroupName, Pattern) -> history_local_oldest_pid(History, Exclude, Node, GroupName, Pattern); history_local_oldest_pid([Pid | _], _, Node, _, Pattern) when node(Pid) =:= Node -> {ok, Pattern, Pid}; history_local_oldest_pid([_ | History], Exclude, Node, GroupName, Pattern) -> history_local_oldest_pid(History, Exclude, Node, GroupName, Pattern). history_local_oldest([_ | _] = History, Exclude, GroupName, Pattern) -> history_local_oldest_pid(lists:reverse(History), Exclude, node(), GroupName, Pattern). history_remote_oldest_pid([], _, GroupName, _) -> {error, {'no_process', GroupName}}; history_remote_oldest_pid([Pid | _], Node, _, Pattern) when node(Pid) =/= Node -> {ok, Pattern, Pid}; history_remote_oldest_pid([_ | History], Node, GroupName, Pattern) -> history_remote_oldest_pid(History, Node, GroupName, Pattern). history_remote_oldest([_ | _] = History, GroupName, Pattern) -> history_remote_oldest_pid(lists:reverse(History), node(), GroupName, Pattern). history_remote_oldest_pid([], _, _, GroupName, _) -> {error, {'no_process', GroupName}}; history_remote_oldest_pid([Exclude | History], Exclude, Node, GroupName, Pattern) -> history_remote_oldest_pid(History, Exclude, Node, GroupName, Pattern); history_remote_oldest_pid([Pid | _], _, Node, _, Pattern) when node(Pid) =/= Node -> {ok, Pattern, Pid}; history_remote_oldest_pid([_ | History], Exclude, Node, GroupName, Pattern) -> history_remote_oldest_pid(History, Exclude, Node, GroupName, Pattern). history_remote_oldest([_ | _] = History, Exclude, GroupName, Pattern) -> history_remote_oldest_pid(lists:reverse(History), Exclude, node(), GroupName, Pattern). history_newest([Pid | _], Pattern) -> {ok, Pattern, Pid}. history_newest_pid([], _, GroupName, _) -> {error, {'no_process', GroupName}}; history_newest_pid([Exclude | History], Exclude, GroupName, Pattern) -> history_newest_pid(History, Exclude, GroupName, Pattern); history_newest_pid([Pid | _], _, _, Pattern) -> {ok, Pattern, Pid}. history_newest([_ | _] = History, Exclude, GroupName, Pattern) -> history_newest_pid(History, Exclude, GroupName, Pattern). history_local_newest_pid([], _, GroupName, _) -> {error, {'no_process', GroupName}}; history_local_newest_pid([Pid | _], Node, _, Pattern) when node(Pid) =:= Node -> {ok, Pattern, Pid}; history_local_newest_pid([_ | History], Node, GroupName, Pattern) -> history_local_newest_pid(History, Node, GroupName, Pattern). history_local_newest([_ | _] = History, GroupName, Pattern) -> history_local_newest_pid(History, node(), GroupName, Pattern). history_local_newest_pid([], _, _, GroupName, _) -> {error, {'no_process', GroupName}}; history_local_newest_pid([Exclude | History], Exclude, Node, GroupName, Pattern) -> history_local_newest_pid(History, Exclude, Node, GroupName, Pattern); history_local_newest_pid([Pid | _], _, Node, _, Pattern) when node(Pid) =:= Node -> {ok, Pattern, Pid}; history_local_newest_pid([_ | History], Exclude, Node, GroupName, Pattern) -> history_local_newest_pid(History, Exclude, Node, GroupName, Pattern). history_local_newest([_ | _] = History, Exclude, GroupName, Pattern) -> history_local_newest_pid(History, Exclude, node(), GroupName, Pattern). history_remote_newest_pid([], _, GroupName, _) -> {error, {'no_process', GroupName}}; history_remote_newest_pid([Pid | _], Node, _, Pattern) when node(Pid) =/= Node -> {ok, Pattern, Pid}; history_remote_newest_pid([_ | History], Node, GroupName, Pattern) -> history_remote_newest_pid(History, Node, GroupName, Pattern). history_remote_newest([_ | _] = History, GroupName, Pattern) -> history_remote_newest_pid(History, node(), GroupName, Pattern). history_remote_newest_pid([], _, _, GroupName, _) -> {error, {'no_process', GroupName}}; history_remote_newest_pid([Exclude | History], Exclude, Node, GroupName, Pattern) -> history_remote_newest_pid(History, Exclude, Node, GroupName, Pattern); history_remote_newest_pid([Pid | _], _, Node, _, Pattern) when node(Pid) =/= Node -> {ok, Pattern, Pid}; history_remote_newest_pid([_ | History], Exclude, Node, GroupName, Pattern) -> history_remote_newest_pid(History, Exclude, Node, GroupName, Pattern). history_remote_newest([_ | _] = History, Exclude, GroupName, Pattern) -> history_remote_newest_pid(History, Exclude, node(), GroupName, Pattern). -compile({inline, [{random,1}]}). random(N) -> quickrand:uniform(N).