Detangle boot error handling, step 2

We used to have a weird situation where an error inside a boot step
would cause us to go through error logging twice. The exception would
get caught in run_step/3, then go through boot_error() etc, and
basic_boot_error/3 would exit again, leading to more stuff being
logged as an application start failure. So to fix that, let's
exit with a special atom which prevents further logging. Also
rename functions to be a bit more meaningful.

1 files changed, 24 insertions, 16 deletions

diff --git a/src/rabbit.erl b/src/rabbit.erl
index 7e35224669..de91f8a39d 100644
--- a/src/rabbit.erl
+++ b/src/rabbit.erl
@@ -334,7 +334,11 @@ start_it(StartFun) ->
                         false -> StartFun()
                     end
                 catch
-                    throw:{could_not_start, _App, _Reason}=Err ->
+                    throw:{could_not_start, rabbit,
+                           boot_failure_already_logged} ->
+                        throw(boot_failure_already_logged),
+                        ok;
+                    throw:{could_not_start, _App, _Reason} = Err ->
                         boot_error(Err, wrapper, not_available);
                     _:Reason ->
                         boot_error(Reason, wrapper, erlang:get_stacktrace())
@@ -387,7 +391,7 @@ stop_apps(Apps) ->
     ok.
 
 handle_app_error(Term) ->
-    fun(App, {bad_return, {_MFA, {'EXIT', {ExitReason, _}}}}) ->
+    fun(App, {bad_return, {_MFA, {'EXIT', ExitReason}}}) ->
             throw({Term, App, ExitReason});
        (App, Reason) ->
             throw({Term, App, Reason})
@@ -593,7 +597,7 @@ sort_boot_steps(UnsortedSteps) ->
 -spec(boot_error/3 :: (term(), atom(), not_available | [tuple()])
                       -> no_return()).
 -endif.
-boot_error(Term={error, {timeout_waiting_for_tables, _}}, _Step, _Stacktrace) ->
+boot_error({error, {timeout_waiting_for_tables, _}}, _Step, _Stacktrace) ->
     AllNodes = rabbit_mnesia:cluster_nodes(all),
     {Err, Nodes} =
         case AllNodes -- [node()] of
@@ -604,30 +608,34 @@ boot_error(Term={error, {timeout_waiting_for_tables, _}}, _Step, _Stacktrace) ->
                      "Timeout contacting cluster nodes: ~p.~n", [Ns]),
                    Ns}
         end,
-    basic_boot_error(Term,
-                     Err ++ rabbit_nodes:diagnostics(Nodes) ++ "~n~n", []);
+    log_boot_error_and_exit(
+      Err ++ rabbit_nodes:diagnostics(Nodes) ++ "~n~n", []);
 boot_error(Reason, Step, Stacktrace) ->
-    Fmt = "Boot step:~n   ~p~n~n"
+    Fmt0 = case Step of
+               wrapper -> "";
+               _       -> rabbit_misc:format("Boot step:~n   ~p~n~n", [Step])
+           end,
+    Fmt = Fmt0 ++
         "Error description:~n   ~p~n~n"
         "Log files (may contain more information):~n   ~s~n   ~s~n~n",
-    Args = [Step, Reason, log_location(kernel), log_location(sasl)],
-    boot_error(Reason, Fmt, Args, Stacktrace).
+    Args = [Reason, log_location(kernel), log_location(sasl)],
+    boot_error1(Fmt, Args, Stacktrace).
 
 -ifdef(use_specs).
--spec(boot_error/4 :: (term(), string(), [any()], not_available | [tuple()])
+-spec(boot_error1/3 :: (string(), [any()], not_available | [tuple()])
                       -> no_return()).
 -endif.
-boot_error(Reason, Fmt, Args, not_available) ->
-    basic_boot_error(Reason, Fmt, Args);
-boot_error(Reason, Fmt, Args, Stacktrace) ->
-    basic_boot_error(Reason, Fmt ++ "Stack trace:~n   ~p~n~n",
-                     Args ++ [Stacktrace]).
+boot_error1(Fmt, Args, not_available) ->
+    log_boot_error_and_exit(Fmt, Args);
+boot_error1(Fmt, Args, Stacktrace) ->
+    log_boot_error_and_exit(Fmt ++ "Stack trace:~n   ~p~n~n",
+                            Args ++ [Stacktrace]).
 
-basic_boot_error(Reason, Format, Args) ->
+log_boot_error_and_exit(Format, Args) ->
     io:format("~n~nBOOT FAILED~n===========~n~n" ++ Format, Args),
     rabbit_log:info(Format, Args),
     timer:sleep(1000),
-    exit({?MODULE, failure_during_boot, Reason}).
+    exit(boot_failure_already_logged).
 
 %%---------------------------------------------------------------------------
 %% boot step functions