Fix use of process_info(Pid, monitored_by)

This can now return references that are from NIFs monitoring the
process. This is important for the new file IO NIFs that monitor the
controlling process. For now we'll just take the easy way out by
filtering the references from our returned monitor lists.

2 files changed, 4 insertions, 3 deletions

diff --git a/src/couch/src/couch_bt_engine.erl b/src/couch/src/couch_bt_engine.erl
index 43a77b071..702899775 100644
--- a/src/couch/src/couch_bt_engine.erl
+++ b/src/couch/src/couch_bt_engine.erl
@@ -185,7 +185,7 @@ decref(St) ->
 monitored_by(St) ->
     case erlang:process_info(St#st.fd, monitored_by) of
         {monitored_by, Pids} ->
-            Pids;
+            lists:filter(fun is_pid/1, Pids);
         _ ->
             []
     end.
diff --git a/src/couch/src/couch_file.erl b/src/couch/src/couch_file.erl
index 9f668ea69..af06b91f8 100644
--- a/src/couch/src/couch_file.erl
+++ b/src/couch/src/couch_file.erl
@@ -129,7 +129,7 @@ append_term_md5(Fd, Term, Options) ->
 
 append_binary(Fd, Bin) ->
     ioq:call(Fd, {append_bin, assemble_file_chunk(Bin)}, erlang:get(io_priority)).
-    
+
 append_binary_md5(Fd, Bin) ->
     ioq:call(Fd,
         {append_bin, assemble_file_chunk(Bin, crypto:hash(md5, Bin))},
@@ -701,7 +701,8 @@ is_idle(#file{is_sys=true}) ->
     end;
 is_idle(#file{is_sys=false}) ->
     Tracker = whereis(couch_stats_process_tracker),
-    case process_info(self(), monitored_by) of
+    {monitored_by, PidsAndRefs} = process_info(self(), monitored_by),
+    case lists:filter(fun is_pid/1, PidsAndRefs) of
         {monitored_by, []} -> true;
         {monitored_by, [Tracker]} -> true;
         {monitored_by, [_]} -> exit(tracker_monitoring_failed);