Add cmux support for inter-cmux comparisons (9db596d2) · Commits · The Tor Project / Core / Tor

src/or/circuitmux.c

+48 −0

Original line number	Diff line number	Diff line
		@@ -1951,3 +1951,51 @@ circuitmux_count_queued_destroy_cells(const channel_t *chan,
		return n_destroy_cells;
		}

		/**
		* Compare cmuxes to see which is more preferred; return < 0 if
		* cmux_1 has higher priority (i.e., cmux_1 < cmux_2 in the scheduler's
		* sort order), > 0 if cmux_2 has higher priority, or 0 if they are
		* equally preferred.
		*
		* If the cmuxes have different cmux policies or the policy does not
		* support the cmp_cmux method, return 0.
		*/

		int
		circuitmux_compare_muxes(circuitmux_t cmux_1, circuitmux_t cmux_2)
		{
		const circuitmux_policy_t *policy;

		tor_assert(cmux_1);
		tor_assert(cmux_2);

		if (cmux_1 == cmux_2) {
		/* Equivalent because they're the same cmux */
		return 0;
		}

		if (cmux_1->policy && cmux_2->policy) {
		if (cmux_1->policy == cmux_2->policy) {
		policy = cmux_1->policy;

		if (policy->cmp_cmux) {
		/* Okay, we can compare! */
		return policy->cmp_cmux(cmux_1, cmux_1->policy_data,
		cmux_2, cmux_2->policy_data);
		} else {
		/*
		* Equivalent because the policy doesn't know how to compare between
		* muxes.
		*/
		return 0;
		}
		} else {
		/* Equivalent because they have different policies */
		return 0;
		}
		} else {
		/* Equivalent because one or both are missing a policy */
		return 0;
		}
		}

+6 −0

Original line number	Diff line number	Diff line
		@@ -57,6 +57,9 @@ struct circuitmux_policy_s {
		/* Choose a circuit */
		circuit_t * (pick_active_circuit)(circuitmux_t cmux,
		circuitmux_policy_data_t *pol_data);
		/* Optional: channel comparator for use by the scheduler */
		int (cmp_cmux)(circuitmux_t cmux_1, circuitmux_policy_data_t *pol_data_1,
		circuitmux_t cmux_2, circuitmux_policy_data_t pol_data_2);
		};

		/*
		@@ -148,5 +151,8 @@ void circuitmux_append_destroy_cell(channel_t *chan,
		void circuitmux_mark_destroyed_circids_usable(circuitmux_t *cmux,
		channel_t *chan);

		/* Optional interchannel comparisons for scheduling */
		int circuitmux_compare_muxes(circuitmux_t cmux_1, circuitmux_t cmux_2);

		#endif /* TOR_CIRCUITMUX_H */