ENG-3822: #451: Check result of weak_ptr lock, before doing actual ca…

…ll in LocalYBInboundCall

Summary:
Because of another issue still under investigation, there could be a case when we invoke LocalYBInboundCall::Response when
original outbound all is already destroyed.
To handle this case correctly we should check that result returned by weak_ptr lock is not null.

Test Plan: Jenknis

Reviewers: robert, mikhail

Reviewed By: mikhail

Subscribers: ybase

Differential Revision: https://phabricator.dev.yugabyte.com/D5388

src/yb/rpc/local_call.cc

@@ -38,7 +38,7 @@ Status LocalOutboundCall::SetRequestParam(const google::protobuf::Message& req)
 }
 
 void LocalOutboundCall::Serialize(std::deque<RefCntBuffer> *output) const {
-  LOG(FATAL) << "local call should not require serialization";
+  LOG(FATAL) << "Local call should not require serialization";
 }
 
 const std::shared_ptr<LocalYBInboundCall>& LocalOutboundCall::CreateLocalInboundCall() {
@@ -77,11 +77,18 @@ const Endpoint& LocalYBInboundCall::local_address() const {
 }
 
 void LocalYBInboundCall::Respond(const google::protobuf::MessageLite& response, bool is_success) {
+  auto call = outbound_call();
+  if (!call) {
+    LOG(DFATAL) << "Outbound call is NULL during Respond, looks like double response. "
+                << "is_success: " << is_success;
+    return;
+  }
+
   if (is_success) {
-    outbound_call()->SetFinished();
+    call->SetFinished();
   } else {
-    outbound_call()->SetFailed(STATUS(RemoteError, "Local call error"),
-                               new ErrorStatusPB(yb::down_cast<const ErrorStatusPB&>(response)));
+    call->SetFailed(STATUS(RemoteError, "Local call error"),
+                    new ErrorStatusPB(yb::down_cast<const ErrorStatusPB&>(response)));
   }
 }