+always_inline u32
+tcp_available_output_snd_space (const tcp_connection_t * tc)
+{
+ u32 available_wnd = tcp_available_snd_wnd (tc);
+ int flight_size = (int) (tc->snd_nxt - tc->snd_una);
+
+ if (available_wnd <= flight_size)
+ return 0;
+
+ return available_wnd - flight_size;
+}
+
+/**
+ * Estimate of how many bytes we can still push into the network
+ */