diff options
Diffstat (limited to 'lib/stdlib/src/gen.erl')
| -rw-r--r-- | lib/stdlib/src/gen.erl | 97 |
1 files changed, 94 insertions, 3 deletions
diff --git a/lib/stdlib/src/gen.erl b/lib/stdlib/src/gen.erl index a7f743bd4c..be14665d80 100644 --- a/lib/stdlib/src/gen.erl +++ b/lib/stdlib/src/gen.erl @@ -28,7 +28,9 @@ %%%----------------------------------------------------------------- -export([start/5, start/6, debug_options/2, hibernate_after/1, name/1, unregister_name/1, get_proc_name/1, get_parent/0, - call/3, call/4, reply/2, stop/1, stop/3]). + call/3, call/4, reply/2, + send_request/3, wait_response/2, check_response/2, + stop/1, stop/3]). -export([init_it/6, init_it/7]). @@ -38,7 +40,7 @@ %%----------------------------------------------------------------- --type linkage() :: 'link' | 'nolink'. +-type linkage() :: 'monitor' | 'link' | 'nolink'. -type emgr_name() :: {'local', atom()} | {'global', term()} | {'via', Module :: module(), Name :: term()}. @@ -53,6 +55,11 @@ | {'spawn_opt', [proc_lib:spawn_option()]}. -type options() :: [option()]. +-type server_ref() :: pid() | atom() | {atom(), node()} + | {global, term()} | {via, module(), term()}. + +-type request_id() :: term(). + %%----------------------------------------------------------------- %% Starts a generic process. %% start(GenMod, LinkP, Mod, Args, Options) @@ -95,6 +102,13 @@ do_spawn(GenMod, link, Mod, Args, Options) -> [GenMod, self(), self(), Mod, Args, Options], Time, spawn_opts(Options)); +do_spawn(GenMod, monitor, Mod, Args, Options) -> + Time = timeout(Options), + Ret = proc_lib:start_monitor(?MODULE, init_it, + [GenMod, self(), self(), Mod, Args, Options], + Time, + spawn_opts(Options)), + monitor_return(Ret); do_spawn(GenMod, _, Mod, Args, Options) -> Time = timeout(Options), proc_lib:start(?MODULE, init_it, @@ -108,6 +122,13 @@ do_spawn(GenMod, link, Name, Mod, Args, Options) -> [GenMod, self(), self(), Name, Mod, Args, Options], Time, spawn_opts(Options)); +do_spawn(GenMod, monitor, Name, Mod, Args, Options) -> + Time = timeout(Options), + Ret = proc_lib:start_monitor(?MODULE, init_it, + [GenMod, self(), self(), Name, Mod, Args, Options], + Time, + spawn_opts(Options)), + monitor_return(Ret); do_spawn(GenMod, _, Name, Mod, Args, Options) -> Time = timeout(Options), proc_lib:start(?MODULE, init_it, @@ -115,6 +136,26 @@ do_spawn(GenMod, _, Name, Mod, Args, Options) -> Time, spawn_opts(Options)). + +%% +%% Adjust monitor returns for OTP gen behaviours... +%% +%% If an OTP behaviour is introduced that 'init_ack's +%% other results, this has code has to be moved out +%% into all behaviours as well as adjusted... +%% +monitor_return({{ok, Pid}, Mon}) when is_pid(Pid), is_reference(Mon) -> + %% Successful start_monitor()... + {ok, {Pid, Mon}}; +monitor_return({Error, Mon}) when is_reference(Mon) -> + %% Failure; wait for spawned process to terminate + %% and release resources, then return the error... + receive + {'DOWN', Mon, process, _Pid, _Reason} -> + ok + end, + Error. + %%----------------------------------------------------------------- %% Initiate the new process. %% Register the name using the Rfunc function @@ -139,7 +180,7 @@ init_it2(GenMod, Starter, Parent, Name, Mod, Args, Options) -> %%----------------------------------------------------------------- %% Makes a synchronous call to a generic process. %% Request is sent to the Pid, and the response must be -%% {Tag, _, Reply}. +%% {Tag, Reply}. %%----------------------------------------------------------------- %%% New call function which uses the new monitor BIF @@ -192,6 +233,56 @@ get_node(Process) -> node(Process) end. +-spec send_request(Name::server_ref(), Label::term(), Request::term()) -> request_id(). +send_request(Process, Label, Request) when is_pid(Process) -> + do_send_request(Process, Label, Request); +send_request(Process, Label, Request) -> + Fun = fun(Pid) -> do_send_request(Pid, Label, Request) end, + try do_for_proc(Process, Fun) + catch exit:Reason -> + %% Make send_request async and fake a down message + Mref = erlang:make_ref(), + self() ! {'DOWN', Mref, process, Process, Reason}, + Mref + end. + +do_send_request(Process, Label, Request) -> + Mref = erlang:monitor(process, Process), + erlang:send(Process, {Label, {self(), {'$gen_request_id', Mref}}, Request}, [noconnect]), + Mref. + +%% +%% Wait for a reply to the client. +%% Note: if timeout is returned monitors are kept. + +-spec wait_response(RequestId::request_id(), timeout()) -> + {reply, Reply::term()} | 'timeout' | {error, {term(), server_ref()}}. +wait_response(Mref, Timeout) + when is_reference(Mref) -> + receive + {{'$gen_request_id', Mref}, Reply} -> + erlang:demonitor(Mref, [flush]), + {reply, Reply}; + {'DOWN', Mref, _, Object, Reason} -> + {error, {Reason, Object}} + after Timeout -> + timeout + end. + +-spec check_response(RequestId::term(), Key::request_id()) -> + {reply, Reply::term()} | 'no_reply' | {error, {term(), server_ref()}}. +check_response(Msg, Mref) + when is_reference(Mref) -> + case Msg of + {{'$gen_request_id', Mref}, Reply} -> + erlang:demonitor(Mref, [flush]), + {reply, Reply}; + {'DOWN', Mref, _, Object, Reason} -> + {error, {Reason, Object}}; + _ -> + no_reply + end. + %% %% Send a reply to the client. %% |