rec: Don't crash when asked to run with zero threads

diff --git a/pdns/pdns_recursor.cc b/pdns/pdns_recursor.cc
index e987037e064f4eb88de1c0e3b9be74e79db6f73e..324c5146871f10f8c99b4e3026ff4ef2a57032bc 100644 (file)
--- a/pdns/pdns_recursor.cc
+++ b/pdns/pdns_recursor.cc
@@ -2986,6 +2986,11 @@ static int serviceMain(int argc, char*argv[])
   g_lowercaseOutgoing = ::arg().mustDo("lowercase-outgoing");
 
   g_numWorkerThreads = ::arg().asNum("threads");
+  if (g_numWorkerThreads < 1) {
+    L<<Logger::Warning<<"Asked to run with 0 threads, raising to 1 instead"<<endl;
+    g_numWorkerThreads = 1;
+  }
+
   g_numThreads = g_numWorkerThreads + g_weDistributeQueries;
   g_maxMThreads = ::arg().asNum("max-mthreads");