diff options
Diffstat (limited to 'lib/stdlib/src/supervisor.erl')
| -rw-r--r-- | lib/stdlib/src/supervisor.erl | 199 |
1 files changed, 135 insertions, 64 deletions
diff --git a/lib/stdlib/src/supervisor.erl b/lib/stdlib/src/supervisor.erl index 22269a8d1b..7102fb9f6e 100644 --- a/lib/stdlib/src/supervisor.erl +++ b/lib/stdlib/src/supervisor.erl @@ -21,7 +21,7 @@ -behaviour(gen_server). %% External exports --export([start_link/2,start_link/3, +-export([start_link/2, start_link/3, start_child/2, restart_child/2, delete_child/2, terminate_child/2, which_children/1, count_children/1, @@ -33,28 +33,56 @@ -export([init/1, handle_call/3, handle_info/2, terminate/2, code_change/3]). -export([handle_cast/2]). +%%-------------------------------------------------------------------------- + +-export_type([child_spec/0, del_err/0, startchild_ret/0, strategy/0]). + +%%-------------------------------------------------------------------------- + +-type child_id() :: pid() | 'undefined'. +-type mfargs() :: {module(), atom(), [term()]}. +-type modules() :: [module()] | 'dynamic'. +-type restart() :: 'permanent' | 'transient' | 'temporary'. +-type shutdown() :: 'brutal_kill' | timeout(). +-type worker() :: 'worker' | 'supervisor'. +-type sup_name() :: {'local', atom()} | {'global', atom()}. +-type sup_ref() :: atom() | {atom(), atom()} | {'global', atom()} | pid(). +-type child_spec() :: {term(),mfargs(),restart(),shutdown(),worker(),modules()}. + +-type strategy() :: 'one_for_all' | 'one_for_one' + | 'rest_for_one' | 'simple_one_for_one'. + +%%-------------------------------------------------------------------------- + +-record(child, {% pid is undefined when child is not running + pid = undefined :: child_id(), + name, + mfargs :: mfargs(), + restart_type :: restart(), + shutdown :: shutdown(), + child_type :: worker(), + modules = [] :: modules()}). +-type child() :: #child{}. + -define(DICT, dict). -record(state, {name, - strategy, - children = [], - dynamics = ?DICT:new(), - intensity, - period, + strategy :: strategy(), + children = [] :: [child()], + dynamics = ?DICT:new() :: ?DICT(), + intensity :: non_neg_integer(), + period :: pos_integer(), restarts = [], module, args}). - --record(child, {pid = undefined, % pid is undefined when child is not running - name, - mfa, - restart_type, - shutdown, - child_type, - modules = []}). +-type state() :: #state{}. -define(is_simple(State), State#state.strategy =:= simple_one_for_one). +%%-------------------------------------------------------------------------- + +-spec behaviour_info(atom()) -> 'undefined' | [{atom(), arity()}]. + behaviour_info(callbacks) -> [{init,1}]; behaviour_info(_Other) -> @@ -65,21 +93,40 @@ behaviour_info(_Other) -> %%% Servers/processes should/could also be built using gen_server.erl. %%% SupName = {local, atom()} | {global, atom()}. %%% --------------------------------------------------- + +-type startlink_err() :: {'already_started', pid()} | 'shutdown' | term(). +-type startlink_ret() :: {'ok', pid()} | 'ignore' | {'error', startlink_err()}. + +-spec start_link(module(), term()) -> startlink_ret(). start_link(Mod, Args) -> gen_server:start_link(supervisor, {self, Mod, Args}, []). +-spec start_link(sup_name(), module(), term()) -> startlink_ret(). start_link(SupName, Mod, Args) -> gen_server:start_link(SupName, supervisor, {SupName, Mod, Args}, []). %%% --------------------------------------------------- %%% Interface functions. %%% --------------------------------------------------- + +-type info() :: term(). +-type startchild_err() :: 'already_present' + | {'already_started', child_id()} | term(). +-type startchild_ret() :: {'ok', child_id()} | {'ok', child_id(), info()} + | {'error', startchild_err()}. + +-spec start_child(sup_ref(), child_spec() | [term()]) -> startchild_ret(). start_child(Supervisor, ChildSpec) -> call(Supervisor, {start_child, ChildSpec}). +-type restart_err() :: 'running' | 'not_found' | 'simple_one_for_one' | term(). +-spec restart_child(sup_ref(), term()) -> + {'ok', child_id()} | {'ok', child_id(), info()} | {'error', restart_err()}. restart_child(Supervisor, Name) -> call(Supervisor, {restart_child, Name}). +-type del_err() :: 'running' | 'not_found' | 'simple_one_for_one'. +-spec delete_child(sup_ref(), term()) -> 'ok' | {'error', del_err()}. delete_child(Supervisor, Name) -> call(Supervisor, {delete_child, Name}). @@ -89,9 +136,13 @@ delete_child(Supervisor, Name) -> %% Note that the child is *always* terminated in some %% way (maybe killed). %%----------------------------------------------------------------- + +-type term_err() :: 'not_found' | 'simple_one_for_one'. +-spec terminate_child(sup_ref(), term()) -> 'ok' | {'error', term_err()}. terminate_child(Supervisor, Name) -> call(Supervisor, {terminate_child, Name}). +-spec which_children(sup_ref()) -> [{term(), child_id(), worker(), modules()}]. which_children(Supervisor) -> call(Supervisor, which_children). @@ -101,6 +152,7 @@ count_children(Supervisor) -> call(Supervisor, Req) -> gen_server:call(Supervisor, Req, infinity). +-spec check_childspecs([child_spec()]) -> 'ok' | {'error', term()}. check_childspecs(ChildSpecs) when is_list(ChildSpecs) -> case check_startspec(ChildSpecs) of {ok, _} -> ok; @@ -113,6 +165,16 @@ check_childspecs(X) -> {error, {badarg, X}}. %%% Initialize the supervisor. %%% %%% --------------------------------------------------- + +-type init_sup_name() :: sup_name() | 'self'. + +-type stop_rsn() :: 'shutdown' | {'bad_return', {module(),'init', term()}} + | {'bad_start_spec', term()} | {'start_spec', term()} + | {'supervisor_data', term()}. + +-spec init({init_sup_name(), module(), [term()]}) -> + {'ok', state()} | 'ignore' | {'stop', stop_rsn()}. + init({SupName, Mod, Args}) -> process_flag(trap_exit, true), case Mod:init(Args) of @@ -130,7 +192,7 @@ init({SupName, Mod, Args}) -> Error -> {stop, {bad_return, {Mod, init, Error}}} end. - + init_children(State, StartSpec) -> SupName = State#state.name, case check_startspec(StartSpec) of @@ -158,12 +220,12 @@ init_dynamic(_State, StartSpec) -> %%----------------------------------------------------------------- %% Func: start_children/2 -%% Args: Children = [#child] in start order -%% SupName = {local, atom()} | {global, atom()} | {pid(),Mod} +%% Args: Children = [child()] in start order +%% SupName = {local, atom()} | {global, atom()} | {pid(), Mod} %% Purpose: Start all children. The new list contains #child's %% with pids. %% Returns: {ok, NChildren} | {error, NChildren} -%% NChildren = [#child] in termination order (reversed +%% NChildren = [child()] in termination order (reversed %% start order) %%----------------------------------------------------------------- start_children(Children, SupName) -> start_children(Children, [], SupName). @@ -182,8 +244,8 @@ start_children([], NChildren, _SupName) -> {ok, NChildren}. do_start_child(SupName, Child) -> - #child{mfa = {M, F, A}} = Child, - case catch apply(M, F, A) of + #child{mfargs = {M, F, Args}} = Child, + case catch apply(M, F, Args) of {ok, Pid} when is_pid(Pid) -> NChild = Child#child{pid = Pid}, report_progress(NChild, SupName), @@ -192,7 +254,7 @@ do_start_child(SupName, Child) -> NChild = Child#child{pid = Pid}, report_progress(NChild, SupName), {ok, Pid, Extra}; - ignore -> + ignore -> {ok, undefined}; {error, What} -> {error, What}; What -> {error, What} @@ -211,15 +273,17 @@ do_start_child_i(M, F, A) -> What -> {error, What} end. - %%% --------------------------------------------------- %%% %%% Callback functions. %%% %%% --------------------------------------------------- +-type call() :: 'which_children' | 'count_children' | {_, _}. % XXX: refine +-spec handle_call(call(), term(), state()) -> {'reply', term(), state()}. + handle_call({start_child, EArgs}, _From, State) when ?is_simple(State) -> - #child{mfa = {M, F, A}} = hd(State#state.children), + #child{mfargs = {M, F, A}} = hd(State#state.children), Args = A ++ EArgs, case do_start_child_i(M, F, Args) of {ok, Pid} -> @@ -235,7 +299,7 @@ handle_call({start_child, EArgs}, _From, State) when ?is_simple(State) -> end; %%% The requests terminate_child, delete_child and restart_child are -%%% invalid for simple_one_for_one supervisors. +%%% invalid for simple_one_for_one supervisors. handle_call({_Req, _Data}, _From, State) when ?is_simple(State) -> {reply, {error, simple_one_for_one}, State}; @@ -297,7 +361,7 @@ handle_call(which_children, _From, State) -> Resp = lists:map(fun(#child{pid = Pid, name = Name, child_type = ChildType, modules = Mods}) -> - {Name, Pid, ChildType, Mods} + {Name, Pid, ChildType, Mods} end, State#state.children), {reply, Resp, State}; @@ -318,7 +382,6 @@ handle_call(count_children, _From, State) when ?is_simple(State) -> {reply, Reply, State}; handle_call(count_children, _From, State) -> - %% Specs and children are together on the children list... {Specs, Active, Supers, Workers} = lists:foldl(fun(Child, Counts) -> @@ -347,15 +410,19 @@ count_child(#child{pid = Pid, child_type = supervisor}, %%% Hopefully cause a function-clause as there is no API function %%% that utilizes cast. +-spec handle_cast('null', state()) -> {'noreply', state()}. + handle_cast(null, State) -> error_logger:error_msg("ERROR: Supervisor received cast-message 'null'~n", []), - {noreply, State}. %% %% Take care of terminated children. %% +-spec handle_info(term(), state()) -> + {'noreply', state()} | {'stop', 'shutdown', state()}. + handle_info({'EXIT', Pid, Reason}, State) -> case restart_child(Pid, Reason, State) of {ok, State1} -> @@ -368,9 +435,12 @@ handle_info(Msg, State) -> error_logger:error_msg("Supervisor received unexpected message: ~p~n", [Msg]), {noreply, State}. + %% %% Terminate this server. %% +-spec terminate(term(), state()) -> 'ok'. + terminate(_Reason, State) -> terminate_children(State#state.children, State#state.name), ok. @@ -384,6 +454,9 @@ terminate(_Reason, State) -> %% NOTE: This requires that the init function of the call-back module %% does not have any side effects. %% +-spec code_change(term(), state(), term()) -> + {'ok', state()} | {'error', term()}. + code_change(_, State, _) -> case (State#state.module):init(State#state.args) of {ok, {SupFlags, StartSpec}} -> @@ -411,7 +484,7 @@ check_flags({Strategy, MaxIntensity, Period}) -> check_flags(What) -> {bad_flags, What}. -update_childspec(State, StartSpec) when ?is_simple(State) -> +update_childspec(State, StartSpec) when ?is_simple(State) -> case check_startspec(StartSpec) of {ok, [Child]} -> {ok, State#state{children = [Child]}}; @@ -437,7 +510,7 @@ update_childspec1([Child|OldC], Children, KeepOld) -> update_childspec1(OldC, Children, [Child|KeepOld]) end; update_childspec1([], Children, KeepOld) -> - % Return them in (keeped) reverse start order. + %% Return them in (kept) reverse start order. lists:reverse(Children ++ KeepOld). update_chsp(OldCh, Children) -> @@ -482,7 +555,7 @@ handle_start_child(Child, State) -> %%% --------------------------------------------------- %%% Restart. A process has terminated. -%%% Returns: {ok, #state} | {shutdown, #state} +%%% Returns: {ok, state()} | {shutdown, state()} %%% --------------------------------------------------- restart_child(Pid, Reason, State) when ?is_simple(State) -> @@ -490,19 +563,19 @@ restart_child(Pid, Reason, State) when ?is_simple(State) -> {ok, Args} -> [Child] = State#state.children, RestartType = Child#child.restart_type, - {M, F, _} = Child#child.mfa, - NChild = Child#child{pid = Pid, mfa = {M, F, Args}}, + {M, F, _} = Child#child.mfargs, + NChild = Child#child{pid = Pid, mfargs = {M, F, Args}}, do_restart(RestartType, Reason, NChild, State); error -> {ok, State} end; restart_child(Pid, Reason, State) -> Children = State#state.children, - case lists:keysearch(Pid, #child.pid, Children) of - {value, Child} -> + case lists:keyfind(Pid, #child.pid, Children) of + #child{} = Child -> RestartType = Child#child.restart_type, do_restart(RestartType, Reason, Child, State); - _ -> + false -> {ok, State} end. @@ -534,7 +607,7 @@ restart(Child, State) -> end. restart(simple_one_for_one, Child, State) -> - #child{mfa = {M, F, A}} = Child, + #child{mfargs = {M, F, A}} = Child, Dynamics = ?DICT:erase(Child#child.pid, State#state.dynamics), case do_start_child_i(M, F, A) of {ok, Pid} -> @@ -580,9 +653,9 @@ restart(one_for_all, Child, State) -> %%----------------------------------------------------------------- %% Func: terminate_children/2 -%% Args: Children = [#child] in termination order +%% Args: Children = [child()] in termination order %% SupName = {local, atom()} | {global, atom()} | {pid(),Mod} -%% Returns: NChildren = [#child] in +%% Returns: NChildren = [child()] in %% startup order (reversed termination order) %%----------------------------------------------------------------- terminate_children(Children, SupName) -> @@ -595,14 +668,15 @@ terminate_children([], _SupName, Res) -> Res. do_terminate(Child, SupName) when Child#child.pid =/= undefined -> - case shutdown(Child#child.pid, - Child#child.shutdown) of - ok -> - Child#child{pid = undefined}; - {error, OtherReason} -> - report_error(shutdown_error, OtherReason, Child, SupName), - Child#child{pid = undefined} - end; + case shutdown(Child#child.pid, Child#child.shutdown) of + ok -> + ok; + {error, normal} when Child#child.restart_type =/= permanent -> + ok; + {error, OtherReason} -> + report_error(shutdown_error, OtherReason, Child, SupName) + end, + Child#child{pid = undefined}; do_terminate(Child, _SupName) -> Child. @@ -617,7 +691,6 @@ do_terminate(Child, _SupName) -> %% Returns: ok | {error, OtherReason} (this should be reported) %%----------------------------------------------------------------- shutdown(Pid, brutal_kill) -> - case monitor_child(Pid) of ok -> exit(Pid, kill), @@ -630,9 +703,7 @@ shutdown(Pid, brutal_kill) -> {error, Reason} -> {error, Reason} end; - shutdown(Pid, Time) -> - case monitor_child(Pid) of ok -> exit(Pid, shutdown), %% Try to shutdown gracefully @@ -738,9 +809,9 @@ remove_child(Child, State) -> %% MaxIntensity = integer() %% Period = integer() %% Mod :== atom() -%% Arsg :== term() +%% Args :== term() %% Purpose: Check that Type is of correct type (!) -%% Returns: {ok, #state} | Error +%% Returns: {ok, state()} | Error %%----------------------------------------------------------------- init_state(SupName, Type, Mod, Args) -> case catch init_state1(SupName, Type, Mod, Args) of @@ -755,11 +826,11 @@ init_state1(SupName, {Strategy, MaxIntensity, Period}, Mod, Args) -> validIntensity(MaxIntensity), validPeriod(Period), {ok, #state{name = supname(SupName,Mod), - strategy = Strategy, - intensity = MaxIntensity, - period = Period, - module = Mod, - args = Args}}; + strategy = Strategy, + intensity = MaxIntensity, + period = Period, + module = Mod, + args = Args}}; init_state1(_SupName, Type, _, _) -> {invalid_type, Type}. @@ -771,26 +842,26 @@ validStrategy(What) -> throw({invalid_strategy, What}). validIntensity(Max) when is_integer(Max), Max >= 0 -> true; -validIntensity(What) -> throw({invalid_intensity, What}). +validIntensity(What) -> throw({invalid_intensity, What}). validPeriod(Period) when is_integer(Period), Period > 0 -> true; validPeriod(What) -> throw({invalid_period, What}). -supname(self,Mod) -> {self(),Mod}; -supname(N,_) -> N. +supname(self, Mod) -> {self(), Mod}; +supname(N, _) -> N. %%% ------------------------------------------------------ %%% Check that the children start specification is valid. %%% Shall be a six (6) tuple %%% {Name, Func, RestartType, Shutdown, ChildType, Modules} %%% where Name is an atom -%%% Func is {Mod, Fun, Args} == {atom, atom, list} +%%% Func is {Mod, Fun, Args} == {atom(), atom(), list()} %%% RestartType is permanent | temporary | transient %%% Shutdown = integer() | infinity | brutal_kill %%% ChildType = supervisor | worker %%% Modules = [atom()] | dynamic -%%% Returns: {ok, [#child]} | Error +%%% Returns: {ok, [child()]} | Error %%% ------------------------------------------------------ check_startspec(Children) -> check_startspec(Children, []). @@ -818,14 +889,14 @@ check_childspec(Name, Func, RestartType, Shutdown, ChildType, Mods) -> validChildType(ChildType), validShutdown(Shutdown, ChildType), validMods(Mods), - {ok, #child{name = Name, mfa = Func, restart_type = RestartType, + {ok, #child{name = Name, mfargs = Func, restart_type = RestartType, shutdown = Shutdown, child_type = ChildType, modules = Mods}}. validChildType(supervisor) -> true; validChildType(worker) -> true; validChildType(What) -> throw({invalid_child_type, What}). -validName(_Name) -> true. +validName(_Name) -> true. validFunc({M, F, A}) when is_atom(M), is_atom(F), @@ -923,7 +994,7 @@ report_error(Error, Reason, Child, SupName) -> extract_child(Child) -> [{pid, Child#child.pid}, {name, Child#child.name}, - {mfa, Child#child.mfa}, + {mfargs, Child#child.mfargs}, {restart_type, Child#child.restart_type}, {shutdown, Child#child.shutdown}, {child_type, Child#child.child_type}]. |