Made can_send/2 into can_send/3.

Author: Matthew Sackman

src/rabbit_amqqueue_process.erl

@@ -175,8 +175,7 @@ deliver_immediately(Message, Delivered,
             C = #cr{limiter_pid = LimiterPid,
                     unsent_message_count = Count,
                     unacked_messages = UAM} = ch_record(ChPid),
-            case not(AckRequired) orelse rabbit_limiter:can_send(
-                                           LimiterPid, self()) of
+            case rabbit_limiter:can_send(LimiterPid, self(), AckRequired) of
                 true ->
                     rabbit_channel:deliver(
                       ChPid, ConsumerTag, AckRequired,

src/rabbit_limiter.erl

@@ -36,7 +36,7 @@
 -export([init/1, terminate/2, code_change/3, handle_call/3, handle_cast/2,
          handle_info/2]).
 -export([start_link/1, shutdown/1]).
--export([limit/2, can_send/2, ack/2, register/2, unregister/2]).
+-export([limit/2, can_send/3, ack/2, register/2, unregister/2]).
 
 %%----------------------------------------------------------------------------
 
@@ -47,7 +47,7 @@
 -spec(start_link/1 :: (pid()) -> pid()).
 -spec(shutdown/1 :: (maybe_pid()) -> 'ok').
 -spec(limit/2 :: (maybe_pid(), non_neg_integer()) -> 'ok').
--spec(can_send/2 :: (maybe_pid(), pid()) -> bool()).
+-spec(can_send/3 :: (maybe_pid(), pid(), bool()) -> bool()).
 -spec(ack/2 :: (maybe_pid(), non_neg_integer()) -> 'ok').
 -spec(register/2 :: (maybe_pid(), pid()) -> 'ok').
 -spec(unregister/2 :: (maybe_pid(), pid()) -> 'ok').
@@ -85,12 +85,12 @@ limit(LimiterPid, PrefetchCount) ->
 
 %% Ask the limiter whether the queue can deliver a message without
 %% breaching a limit
-can_send(undefined, _QPid) ->
+can_send(undefined, _QPid, _AckRequired) ->
     true;
-can_send(LimiterPid, QPid) ->
+can_send(LimiterPid, QPid, AckRequired) ->
     rabbit_misc:with_exit_handler(
       fun () -> true end,
-      fun () -> gen_server2:call(LimiterPid, {can_send, QPid}, infinity) end).
+      fun () -> gen_server2:call(LimiterPid, {can_send, QPid, AckRequired}, infinity) end).
 
 %% Let the limiter know that the channel has received some acks from a
 %% consumer
@@ -110,10 +110,13 @@ unregister(LimiterPid, QPid) -> gen_server2:cast(LimiterPid, {unregister, QPid})
 init([ChPid]) ->
     {ok, #lim{ch_pid = ChPid} }.
 
-handle_call({can_send, QPid}, _From, State = #lim{volume = Volume}) ->
+handle_call({can_send, QPid, AckRequired}, _From, State = #lim{volume = Volume}) ->
+    Volume1 = if AckRequired -> Volume + 1;
+                 true -> Volume
+              end,
     case limit_reached(State) of
         true  -> {reply, false, limit_queue(QPid, State)};
-        false -> {reply, true, State#lim{volume = Volume + 1}}
+        false -> {reply, true, State#lim{volume = Volume1}}
     end.
 
 handle_cast(shutdown, State) ->