main: Add mainloop callback event flags

Implement the ability to set flags per events which influences the set up of
the event.

This commit only adds one flag which is "need network" meaning that the event
is not enabled if tor has disabled the network or if hibernation mode.

Signed-off-by: David Goulet <dgoulet@torproject.org>

1 files changed, 46 insertions, 29 deletions

diff --git a/src/or/main.c b/src/or/main.c
index a7896fafa5..c7bd720ccf 100644
--- a/src/or/main.c
+++ b/src/or/main.c
@@ -1362,54 +1362,65 @@ CALLBACK(write_stats_file);
 #undef CALLBACK
 
 /* Now we declare an array of periodic_event_item_t for each periodic event */
-#define CALLBACK(name, r) PERIODIC_EVENT(name, r)
+#define CALLBACK(name, r, f) PERIODIC_EVENT(name, r, f)
 
 STATIC periodic_event_item_t periodic_events[] = {
   /* Everyone needs to run those. */
-  CALLBACK(add_entropy, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(check_expired_networkstatus, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(clean_caches, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(fetch_networkstatus, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(heartbeat, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(launch_descriptor_fetches, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(reset_padding_counts, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(retry_listeners, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(rotate_x509_certificate, PERIODIC_EVENT_ROLE_ALL),
-  CALLBACK(write_stats_file, PERIODIC_EVENT_ROLE_ALL),
+  CALLBACK(add_entropy, PERIODIC_EVENT_ROLE_ALL, 0),
+  CALLBACK(check_expired_networkstatus, PERIODIC_EVENT_ROLE_ALL, 0),
+  CALLBACK(clean_caches, PERIODIC_EVENT_ROLE_ALL, 0),
+  CALLBACK(fetch_networkstatus, PERIODIC_EVENT_ROLE_ALL,
+           PERIODIC_EVENT_FLAG_NEED_NET),
+  CALLBACK(heartbeat, PERIODIC_EVENT_ROLE_ALL, 0),
+  CALLBACK(launch_descriptor_fetches, PERIODIC_EVENT_ROLE_ALL,
+           PERIODIC_EVENT_FLAG_NEED_NET),
+  CALLBACK(reset_padding_counts, PERIODIC_EVENT_ROLE_ALL, 0),
+  CALLBACK(retry_listeners, PERIODIC_EVENT_ROLE_ALL,
+           PERIODIC_EVENT_FLAG_NEED_NET),
+  CALLBACK(rotate_x509_certificate, PERIODIC_EVENT_ROLE_ALL, 0),
+  CALLBACK(write_stats_file, PERIODIC_EVENT_ROLE_ALL, 0),
 
   /* Routers (bridge and relay) only. */
-  CALLBACK(check_descriptor, PERIODIC_EVENT_ROLE_ROUTER),
-  CALLBACK(check_ed_keys, PERIODIC_EVENT_ROLE_ROUTER),
-  CALLBACK(check_for_reachability_bw, PERIODIC_EVENT_ROLE_ROUTER),
-  CALLBACK(check_onion_keys_expiry_time, PERIODIC_EVENT_ROLE_ROUTER),
-  CALLBACK(clean_consdiffmgr, PERIODIC_EVENT_ROLE_ROUTER),
-  CALLBACK(expire_old_ciruits_serverside, PERIODIC_EVENT_ROLE_ROUTER),
-  CALLBACK(retry_dns, PERIODIC_EVENT_ROLE_ROUTER),
-  CALLBACK(rotate_onion_key, PERIODIC_EVENT_ROLE_ROUTER),
+  CALLBACK(check_descriptor, PERIODIC_EVENT_ROLE_ROUTER,
+           PERIODIC_EVENT_FLAG_NEED_NET),
+  CALLBACK(check_ed_keys, PERIODIC_EVENT_ROLE_ROUTER, 0),
+  CALLBACK(check_for_reachability_bw, PERIODIC_EVENT_ROLE_ROUTER,
+           PERIODIC_EVENT_FLAG_NEED_NET),
+  CALLBACK(check_onion_keys_expiry_time, PERIODIC_EVENT_ROLE_ROUTER, 0),
+  CALLBACK(clean_consdiffmgr, PERIODIC_EVENT_ROLE_ROUTER, 0),
+  CALLBACK(expire_old_ciruits_serverside, PERIODIC_EVENT_ROLE_ROUTER,
+           PERIODIC_EVENT_FLAG_NEED_NET),
+  CALLBACK(retry_dns, PERIODIC_EVENT_ROLE_ROUTER, 0),
+  CALLBACK(rotate_onion_key, PERIODIC_EVENT_ROLE_ROUTER, 0),
 
   /* Authorities (bridge and directory) only. */
-  CALLBACK(downrate_stability, PERIODIC_EVENT_ROLE_AUTHORITIES),
-  CALLBACK(launch_reachability_tests, PERIODIC_EVENT_ROLE_AUTHORITIES),
-  CALLBACK(save_stability, PERIODIC_EVENT_ROLE_AUTHORITIES),
+  CALLBACK(downrate_stability, PERIODIC_EVENT_ROLE_AUTHORITIES, 0),
+  CALLBACK(launch_reachability_tests, PERIODIC_EVENT_ROLE_AUTHORITIES,
+           PERIODIC_EVENT_FLAG_NEED_NET),
+  CALLBACK(save_stability, PERIODIC_EVENT_ROLE_AUTHORITIES, 0),
 
   /* Directory authority only. */
-  CALLBACK(check_authority_cert, PERIODIC_EVENT_ROLE_DIRAUTH),
+  CALLBACK(check_authority_cert, PERIODIC_EVENT_ROLE_DIRAUTH, 0),
 
   /* Relay only. */
-  CALLBACK(check_canonical_channels, PERIODIC_EVENT_ROLE_RELAY),
-  CALLBACK(check_dns_honesty, PERIODIC_EVENT_ROLE_RELAY),
+  CALLBACK(check_canonical_channels, PERIODIC_EVENT_ROLE_RELAY,
+           PERIODIC_EVENT_FLAG_NEED_NET),
+  CALLBACK(check_dns_honesty, PERIODIC_EVENT_ROLE_RELAY,
+           PERIODIC_EVENT_FLAG_NEED_NET),
 
   /* Hidden Service service only. */
-  CALLBACK(hs_service, PERIODIC_EVENT_ROLE_HS_SERVICE),
+  CALLBACK(hs_service, PERIODIC_EVENT_ROLE_HS_SERVICE,
+           PERIODIC_EVENT_FLAG_NEED_NET),
 
   /* Bridge only. */
-  CALLBACK(record_bridge_stats, PERIODIC_EVENT_ROLE_BRIDGE),
+  CALLBACK(record_bridge_stats, PERIODIC_EVENT_ROLE_BRIDGE, 0),
 
   /* Client only. */
-  CALLBACK(rend_cache_failure_clean, PERIODIC_EVENT_ROLE_CLIENT),
+  CALLBACK(rend_cache_failure_clean, PERIODIC_EVENT_ROLE_CLIENT, 0),
 
   /* Bridge Authority only. */
-  CALLBACK(write_bridge_ns, PERIODIC_EVENT_ROLE_BRIDGEAUTH),
+  CALLBACK(write_bridge_ns, PERIODIC_EVENT_ROLE_BRIDGEAUTH, 0),
+
   END_OF_PERIODIC_EVENTS
 };
 #undef CALLBACK
@@ -1548,6 +1559,12 @@ rescan_periodic_events(const or_options_t *options)
   for (int i = 0; periodic_events[i].name; ++i) {
     periodic_event_item_t *item = &periodic_events[i];
 
+    /* Handle the event flags. */
+    if (net_is_disabled() &&
+        (item->flags & PERIODIC_EVENT_FLAG_NEED_NET)) {
+      continue;
+    }
+
     /* Enable the event if needed. It is safe to enable an event that was
      * already enabled. Same goes for disabling it. */
     if (item->roles & roles) {