diff options
| -rw-r--r-- | src/libsystemd/sd-bus/bus-track.c | 34 |
1 files changed, 30 insertions, 4 deletions
diff --git a/src/libsystemd/sd-bus/bus-track.c b/src/libsystemd/sd-bus/bus-track.c index 6ece2244c2..90e0c7ae01 100644 --- a/src/libsystemd/sd-bus/bus-track.c +++ b/src/libsystemd/sd-bus/bus-track.c @@ -32,6 +32,7 @@ struct track_item { struct sd_bus_track { unsigned n_ref; + unsigned n_adding; /* are we in the process of adding a new name? */ sd_bus *bus; sd_bus_track_handler_t handler; void *userdata; @@ -80,9 +81,23 @@ DEFINE_TRIVIAL_CLEANUP_FUNC(struct track_item*, track_item_free); static void bus_track_add_to_queue(sd_bus_track *track) { assert(track); + /* Adds the bus track object to the queue of objects we should dispatch next, subject to a number of + * conditions. */ + + /* Already in the queue? */ if (track->in_queue) return; + /* if we are currently in the process of adding a new name, then let's not enqueue this just yet, let's wait + * until the addition is complete. */ + if (track->n_adding > 0) + return; + + /* still referenced? */ + if (hashmap_size(track->names) > 0) + return; + + /* Nothing to call? */ if (!track->handler) return; @@ -112,8 +127,7 @@ static int bus_track_remove_name_fully(sd_bus_track *track, const char *name) { track_item_free(i); - if (hashmap_isempty(track->names)) - bus_track_add_to_queue(track); + bus_track_add_to_queue(track); track->modified = true; return 1; @@ -237,18 +251,30 @@ _public_ int sd_bus_track_add_name(sd_bus_track *track, const char *name) { /* First, subscribe to this name */ match = MATCH_FOR_NAME(name); + + bus_track_remove_from_queue(track); /* don't dispatch this while we work in it */ + + track->n_adding++; /* make sure we aren't dispatched while we synchronously add this match */ r = sd_bus_add_match(track->bus, &n->slot, match, on_name_owner_changed, track); - if (r < 0) + track->n_adding--; + if (r < 0) { + bus_track_add_to_queue(track); return r; + } r = hashmap_put(track->names, n->name, n); - if (r < 0) + if (r < 0) { + bus_track_add_to_queue(track); return r; + } /* Second, check if it is currently existing, or maybe doesn't, or maybe disappeared already. */ + track->n_adding++; /* again, make sure this isn't dispatch while we are working in it */ r = sd_bus_get_name_creds(track->bus, name, 0, NULL); + track->n_adding--; if (r < 0) { hashmap_remove(track->names, name); + bus_track_add_to_queue(track); return r; } |