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-rw-r--r--lib/stdlib/src/supervisor.erl172
1 files changed, 117 insertions, 55 deletions
diff --git a/lib/stdlib/src/supervisor.erl b/lib/stdlib/src/supervisor.erl
index 22269a8d1b..f5d5441184 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,
@@ -33,25 +33,47 @@
-export([init/1, handle_call/3, handle_info/2, terminate/2, code_change/3]).
-export([handle_cast/2]).
+-export_type([child_spec/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).
@@ -65,21 +87,40 @@ 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 +130,13 @@ 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 +146,7 @@ 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 +159,14 @@ check_childspecs(X) -> {error, {badarg, X}}.
%%% Initialize the supervisor.
%%%
%%% ---------------------------------------------------
+
+-type stop_rsn() :: 'shutdown' | {'bad_return', {module(),'init', term()}}
+ | {'bad_start_spec', term()} | {'start_spec', term()}
+ | {'supervisor_data', term()}.
+
+-spec 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
@@ -158,12 +212,12 @@ 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 +236,8 @@ 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 +246,7 @@ 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 +265,17 @@ 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 +291,7 @@ 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 +353,7 @@ 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 +374,6 @@ 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 +402,19 @@ 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 +427,12 @@ 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 +446,9 @@ 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 +476,7 @@ 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 +502,7 @@ 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 +547,7 @@ 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 +555,19 @@ 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 +599,7 @@ 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 +645,9 @@ 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) ->
@@ -617,7 +682,6 @@ 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 +694,7 @@ 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 +800,9 @@ 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 +817,11 @@ 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 +833,26 @@ 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 +880,14 @@ 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 +985,7 @@ 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}].