Avoid leaking socket filedescriptors

When trying the various results of getaddrinfo, we forgot to close the
socket when one fails, before trying the next one.

Also use the destructor to make sure we do not have some other unrelated
leak.

louloulibs/network/tcp_socket_handler.cpp

@@ -44,8 +44,16 @@ TCPSocketHandler::TCPSocketHandler(std::shared_ptr<Poller> poller):
 #endif
 {}
 
+TCPSocketHandler::~TCPSocketHandler()
+{
+  this->close();
+}
+
+
 void TCPSocketHandler::init_socket(const struct addrinfo* rp)
 {
+  if (this->socket != -1)
+    ::close(this->socket);
   if ((this->socket = ::socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol)) == -1)
     throw std::runtime_error("Could not create socket: "s + strerror(errno));
   int optval = 1;

louloulibs/network/tcp_socket_handler.hpp

@@ -27,7 +27,7 @@
 class TCPSocketHandler: public SocketHandler
 {
 protected:
-  ~TCPSocketHandler() = default;
+  ~TCPSocketHandler();
 
 public:
   explicit TCPSocketHandler(std::shared_ptr<Poller> poller);