From 21a3dd92a7cf89cf3a9c441c1c137e0f05451ebc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=B6lvi=20P=C3=A1ll=20=C3=81sgeirsson?= <solvi@kodi.is>
Date: Tue, 27 Oct 2015 13:58:52 +0000
Subject: [PATCH] Work around a race condition when deleting slide counters

If SampleMod:trim/2 gets called by a folsom_sample_slide_server after the ETS table the server is trimming has gone away, it will go into a restart loop and eventually bring down the folsom_sample_slide_sup supervisor.
This fixes that by catching badarg and stopping the erronous process normally.
---
 src/folsom_sample_slide_server.erl | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/folsom_sample_slide_server.erl b/src/folsom_sample_slide_server.erl
index f02b4a2..a413a34 100644
--- a/src/folsom_sample_slide_server.erl
+++ b/src/folsom_sample_slide_server.erl
@@ -65,8 +65,14 @@ handle_cast(_Msg, State) ->
     {noreply, State}.
 
 handle_info(timeout, State=#state{sample_mod = SampleMod, reservoir = Reservoir, window = Window}) ->
-    SampleMod:trim(Reservoir, Window),
-    {noreply, State, timeout(Window)};
+    try
+	SampleMod:trim(Reservoir, Window),
+	{noreply, State, timeout(Window)}
+    catch error:badarg ->
+	    %% The ets table must have gone away; stop normally instead of bringing
+	    %% the supervisor down with us.
+	    {stop, normal, State}
+    end;
 handle_info(_Info, State) ->
     {noreply, State}.