From 068c763422b5830dc15598089f7760e79f5bdf81 Mon Sep 17 00:00:00 2001
From: Peter van Dijk <peter.van.dijk@powerdns.com>
Date: Fri, 28 Oct 2016 15:31:53 +0200
Subject: [PATCH] extract nested exception from Luawrapper

Before:
Oct 28 15:30:34 STL error (www.foobar.com/A from 127.0.0.1): Exception thrown by a callback function called by Lua

After:
Oct 28 15:30:34 STL error (www.foobar.com/A from 127.0.0.1): Exception thrown by a callback function called by Lua. Extra info: Found . in wrong position in DNSName www.foobar.com..internal

reported by @elad, thanks!
---
 pdns/pdns_recursor.cc | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/pdns/pdns_recursor.cc b/pdns/pdns_recursor.cc
index d98f0803d..4435bab3f 100644
--- a/pdns/pdns_recursor.cc
+++ b/pdns/pdns_recursor.cc
@@ -1183,7 +1183,16 @@ void startDoResolve(void *p)
     delete dc;
   }
   catch(std::exception& e) {
-    L<<Logger::Error<<"STL error "<< makeLoginfo(dc)<<": "<<e.what()<<endl;
+    L<<Logger::Error<<"STL error "<< makeLoginfo(dc)<<": "<<e.what();
+
+    // Luawrapper nests the exception from Lua, so we unnest it here
+    try {
+        std::rethrow_if_nested(e);
+    } catch(const std::exception& e) {
+        L<<". Extra info: "<<e.what();
+    } catch(...) {}
+
+    L<<endl;
     delete dc;
   }
   catch(...) {
-- 
2.40.0