From 5f3ea719133bb528dd2b2ea4bca875b56a8cedee Mon Sep 17 00:00:00 2001
From: Pieter Lexis <pieter.lexis@powerdns.com>
Date: Wed, 26 Oct 2016 19:32:23 +0200
Subject: [PATCH] Don't exit dnsdist on an exception in maintenance

This change logs every minute if the maintenance function throws an
exception.
---
 pdns/dnsdist.cc | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/pdns/dnsdist.cc b/pdns/dnsdist.cc
index e390131516..6ea4b1a39a 100644
--- a/pdns/dnsdist.cc
+++ b/pdns/dnsdist.cc
@@ -1247,15 +1247,27 @@ void* maintThread()
 {
   int interval = 1;
   size_t counter = 0;
+  int32_t secondsToWaitLog = 0;
 
   for(;;) {
     sleep(interval);
 
     {
       std::lock_guard<std::mutex> lock(g_luamutex);
-      auto f =g_lua.readVariable<boost::optional<std::function<void()> > >("maintenance");
-      if(f)
-        (*f)();
+      auto f = g_lua.readVariable<boost::optional<std::function<void()> > >("maintenance");
+      if(f) {
+        try {
+          (*f)();
+          secondsToWaitLog = 0;
+        }
+        catch(std::exception &e) {
+          if (secondsToWaitLog <= 0) {
+            infolog("Error during execution of maintenance function: %s", e.what());
+            secondsToWaitLog = 61;
+          }
+          secondsToWaitLog -= interval;
+        }
+      }
     }
 
     counter++;
-- 
2.47.2