Handle runtime fast open check correctly

src/local.c

@@ -404,10 +404,13 @@ server_recv_cb(EV_P_ ev_io *w, int revents)
                             ev_io_start(EV_A_ & remote->send_ctx->io);
                             return;
                         } else {
-                            if (errno == ENOTCONN) {
+                            if (errno == EOPNOTSUPP || errno == EPROTONOSUPPORT ||
+                                    errno == ENOPROTOOPT) {
                                 LOGE("fast open is not supported on this platform");
                                 // just turn it off
                                 fast_open = 0;
+                            } else {
+                                ERROR("fast_open_connect");
                             }
                             close_and_free_remote(EV_A_ remote);
                             close_and_free_server(EV_A_ server);

src/redir.c

@@ -578,8 +578,13 @@ remote_send_cb(EV_P_ ev_io *w, int revents)
                     ev_io_start(EV_A_ & remote_send_ctx->io);
                     ev_timer_start(EV_A_ & remote_send_ctx->watcher);
                 } else {
-                    fast_open = 0;
-                    LOGE("fast open is not supported on this platform");
+                    if (errno == EOPNOTSUPP || errno == EPROTONOSUPPORT ||
+                            errno == ENOPROTOOPT) {
+                        fast_open = 0;
+                        LOGE("fast open is not supported on this platform");
+                    } else {
+                        ERROR("fast_open_connect");
+                    }
                     close_and_free_remote(EV_A_ remote);
                     close_and_free_server(EV_A_ server);
                 }

src/server.c

@@ -543,7 +543,7 @@ connect_to_remote(EV_P_ struct addrinfo *res,
                 fast_open = 0;
                 LOGE("fast open is not supported on this platform");
             } else {
-                ERROR("sendto");
+                ERROR("fast_open_connect");
             }
         } else {
             server->buf->idx += s;