Merge branch 'sa/callback-attr'

* sa/callback-attr:
  Add callback specs into 'application' module in kernel
  Add callback specs to tftp module following internet documentation
  Add callback specs to inets_service module following possibly deprecated comments
  Add '-callback' attributes in stdlib's behaviours
  Update primary bootstrap
  Update the documentation with information on the callback attribute
  Automatically generate 'behaviour_info' function from '-callback' attributes
  Add '-callback' attribute to language syntax

OTP-9621

1 files changed, 32 insertions, 9 deletions

diff --git a/lib/stdlib/src/gen_fsm.erl b/lib/stdlib/src/gen_fsm.erl
index ea21136bdb..3db8c9f4f2 100644
--- a/lib/stdlib/src/gen_fsm.erl
+++ b/lib/stdlib/src/gen_fsm.erl
@@ -113,8 +113,6 @@
 	 start_timer/2,send_event_after/2,cancel_timer/1,
 	 enter_loop/4, enter_loop/5, enter_loop/6, wake_hib/6]).
 
--export([behaviour_info/1]).
-
 %% Internal exports
 -export([init_it/6,
 	 system_continue/3,
@@ -128,13 +126,38 @@
 %%% Interface functions.
 %%% ---------------------------------------------------
 
--spec behaviour_info(atom()) -> 'undefined' | [{atom(), arity()}].
-
-behaviour_info(callbacks) ->
-    [{init,1},{handle_event,3},{handle_sync_event,4},{handle_info,3},
-     {terminate,3},{code_change,4}];
-behaviour_info(_Other) ->
-    undefined.
+-callback init(Args :: term()) ->
+    {ok, StateName :: atom(), StateData :: term()} |
+    {ok, StateName :: atom(), StateData :: term(), timeout() | hibernate} |
+    {stop, Reason :: term()} | ignore.
+-callback handle_event(Event :: term(), StateName :: atom(),
+                       StateData :: term()) ->
+    {next_state, NextStateName :: atom(), NewStateData :: term()} |
+    {next_state, NextStateName :: atom(), NewStateData :: term(),
+     timeout() | hibernate} |
+    {stop, Reason :: term(), NewStateData :: term()}.
+-callback handle_sync_event(Event :: term(), From :: {pid(), Tag :: term()},
+                            StateName :: atom(), StateData :: term()) ->
+    {reply, Reply :: term(), NextStateName :: atom(), NewStateData :: term()} |
+    {reply, Reply :: term(), NextStateName :: atom(), NewStateData :: term(),
+     timeout() | hibernate} |
+    {next_state, NextStateName :: atom(), NewStateData :: term()} |
+    {next_state, NextStateName :: atom(), NewStateData :: term(),
+     timeout() | hibernate} |
+    {stop, Reason :: term(), Reply :: term(), NewStateData :: term()} |
+    {stop, Reason :: term(), NewStateData :: term()}.
+-callback handle_info(Info :: term(), StateName :: atom(),
+                      StateData :: term()) ->
+    {next_state, NextStateName :: atom(), NewStateData :: term()} |
+    {next_state, NextStateName :: atom(), NewStateData :: term(),
+     timeout() | hibernate} |
+    {stop, Reason :: normal | term(), NewStateData :: term()}.
+-callback terminate(Reason :: normal | shutdown | {shutdown, term()}
+		    | term(), StateName :: atom(), StateData :: term()) ->
+    term().
+-callback code_change(OldVsn :: term() | {down, term()}, StateName :: atom(),
+		      StateData :: term(), Extra :: term()) ->
+    {ok, NextStateName :: atom(), NewStateData :: term()}.
 
 %%% ---------------------------------------------------
 %%% Starts a generic state machine.