Merge pull request #18 from niklas88/driveby_cleanups

Set SO_KEEPALIVE on client sockets

src/engine/Server.cpp

@@ -64,6 +64,9 @@ void Server::run() {
       LOG(ERROR) << "Socket error while trying to accept client" << std::endl;
       continue;
     }
+    // Setting Keep Alive on the socket helps detect vanished clients
+    // instead of blocking operations idefinitely
+    client.setKeepAlive(true);
     // TODO(buchholb): Spawn a new thread here / use a ThreadPool / etc.
     LOG(INFO) << "Incoming connection, processing..." << std::endl;
     process(&client, &qec);

src/util/Socket.h

@@ -65,6 +65,15 @@ class Socket {
     return isOpen();
   }
 
+  void setKeepAlive(bool keepAlive) const {
+    int keepAliveVal = (keepAlive) ? 1 : 0;
+    int rc = setsockopt(_fd, SOL_SOCKET,
+        SO_KEEPALIVE, &keepAliveVal, sizeof(keepAliveVal));
+    if (rc < 0) {
+      LOG(WARN) << "setsockopt(SO_KEEPALIVE) failed" << std::endl;
+    }
+  }
+
   void makeResusableAfterClosing() const {
     // Make sockets reusable immediately after closing
     int on = 1;