rec: Handle failure to start the web server more gracefully

At this point we already have several threads so calling exit()
will cause problem by trying to destruct objects that are in use
by other threads, so call _exit() instead.
Also mention the web server in the error message so that the root
cause is easier to identify.

diff --git a/pdns/pdns_recursor.cc b/pdns/pdns_recursor.cc
index f3a5d17d68b4f4c1a2a5e959c33f1c3a888d8935..6c9e641e97742ceb6b58787dc523e6ab0ee71698 100644 (file)
--- a/pdns/pdns_recursor.cc
+++ b/pdns/pdns_recursor.cc
@@ -3658,7 +3658,7 @@ static bool trySendingQueryToWorker(unsigned int target, ThreadMSG* tmsg)
   auto& targetInfo = s_threadInfos[target];
   if(!targetInfo.isWorker) {
     g_log<<Logger::Error<<"distributeAsyncFunction() tried to assign a query to a non-worker thread"<<endl;
-    exit(1);
+    _exit(1);
   }
 
   const auto& tps = targetInfo.pipes;
@@ -3731,7 +3731,7 @@ void distributeAsyncFunction(const string& packet, const pipefunc_t& func)
 {
   if (!isDistributorThread()) {
     g_log<<Logger::Error<<"distributeAsyncFunction() has been called by a worker ("<<t_id<<")"<<endl;
-    exit(1);
+    _exit(1);
   }
 
   unsigned int hash = hashQuestion(packet.c_str(), packet.length(), g_disthashseed);
@@ -3813,7 +3813,7 @@ template<class T> T broadcastAccFunction(const boost::function<T*()>& func)
 {
   if (!isHandlerThread()) {
     g_log<<Logger::Error<<"broadcastAccFunction has been called by a worker ("<<t_id<<")"<<endl;
-    exit(1);
+    _exit(1);
   }
 
   unsigned int n = 0;
@@ -4068,7 +4068,7 @@ static FDMultiplexer* getMultiplexer()
     }
   }
   g_log<<Logger::Error<<"No working multiplexer found!"<<endl;
-  exit(1);
+  _exit(1);
 }
 
 
@@ -5086,9 +5086,9 @@ try
       try {
         rws = new RecursorWebServer(t_fdm);
       }
-      catch(PDNSException &e) {
-        g_log<<Logger::Error<<"Exception: "<<e.reason<<endl;
-        exit(99);
+      catch (const PDNSException &e) {
+        g_log<<Logger::Error<<"Unable to start the internal web server: "<<e.reason<<endl;
+        _exit(99);
       }
     }
     g_log<<Logger::Info<<"Enabled '"<< t_fdm->getName() << "' multiplexer"<<endl;

diff --git a/pdns/ws-recursor.cc b/pdns/ws-recursor.cc
index d80b6897772c11283b3a49598f6c56ea0dc0f347..1c31c1f7face0294161b714a4bd46c07c7f8d076 100644 (file)
--- a/pdns/ws-recursor.cc
+++ b/pdns/ws-recursor.cc
@@ -509,7 +509,8 @@ RecursorWebServer::RecursorWebServer(FDMultiplexer* fdm)
 {
   registerAllStats();
 
-  d_ws = std::unique_ptr<AsyncWebServer>(new AsyncWebServer(fdm, arg()["webserver-address"], arg().asNum("webserver-port")));
+  d_ws = make_unique<AsyncWebServer>(fdm, arg()["webserver-address"], arg().asNum("webserver-port"));
+
   d_ws->setApiKey(arg()["api-key"]);
   d_ws->setPassword(arg()["webserver-password"]);
   d_ws->setLogLevel(arg()["webserver-loglevel"]);
@@ -534,8 +535,10 @@ RecursorWebServer::RecursorWebServer(FDMultiplexer* fdm)
   d_ws->registerApiHandler("/api/v1/servers", &apiServer);
   d_ws->registerApiHandler("/api", &apiDiscovery);
 
-  for(const auto& u : g_urlmap) 
+  for (const auto& u : g_urlmap) {
     d_ws->registerWebHandler("/"+u.first, serveStuff);
+  }
+
   d_ws->registerWebHandler("/", serveStuff);
   d_ws->registerWebHandler("/metrics", prometheusMetrics);
   d_ws->go();