commit 9db596d2ef441d9293f5341be28150739baac98d Author: Andrea Shepard andrea@torproject.org Date: Sat Nov 30 01:25:20 2013 -0800

Add cmux support for inter-cmux comparisons --- src/or/circuitmux.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ src/or/circuitmux.h | 6 ++++++ 2 files changed, 54 insertions(+)

diff --git a/src/or/circuitmux.c b/src/or/circuitmux.c index 3ca33b0..29c3be1 100644 --- a/src/or/circuitmux.c +++ b/src/or/circuitmux.c @@ -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; + } +} + diff --git a/src/or/circuitmux.h b/src/or/circuitmux.h index 2b5fb7e..5833ee5 100644 --- a/src/or/circuitmux.h +++ b/src/or/circuitmux.h @@ -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 */