Quicker resource cleanup on p2p socks timeout

src/net/socks.h

@@ -201,6 +201,13 @@ namespace socks
             std::shared_ptr<client> self_;
             void operator()(boost::system::error_code error = boost::system::error_code{});
         };
+
+        //! Calls `async_close` on `self` at destruction. NOP if `nullptr`.
+        struct close_on_exit
+        {
+            std::shared_ptr<client> self;
+            ~close_on_exit() { async_close{std::move(self)}(); }
+        };
     };
 
     template<typename Handler>

src/p2p/net_node.cpp

@@ -339,6 +339,7 @@ namespace nodetool
             }
         };
 
+        net::socks::client::close_on_exit close_client{};
         boost::unique_future<client_result> socks_result{};
         {
             boost::promise<client_result> socks_promise{};
@@ -347,6 +348,7 @@ namespace nodetool
             auto client = net::socks::make_connect_client(
                 boost::asio::ip::tcp::socket{service}, net::socks::version::v4a, notify{std::move(socks_promise)}
              );
+            close_client.self = client;
             if (!start_socks(std::move(client), proxy, remote))
                 return boost::none;
         }
@@ -368,7 +370,10 @@ namespace nodetool
         {
             auto result = socks_result.get();
             if (!result.first)
+            {
+                close_client.self.reset();
                 return {std::move(result.second)};
+            }
 
             MERROR("Failed to make socks connection to " << remote.str() << " (via " << proxy << "): " << result.first.message());
         }