diff options
Diffstat (limited to 'src/libsystemd/sd-bus/bus-track.c')
| -rw-r--r-- | src/libsystemd/sd-bus/bus-track.c | 262 |
1 files changed, 225 insertions, 37 deletions
diff --git a/src/libsystemd/sd-bus/bus-track.c b/src/libsystemd/sd-bus/bus-track.c index 1f436fe560..4acaf24793 100644 --- a/src/libsystemd/sd-bus/bus-track.c +++ b/src/libsystemd/sd-bus/bus-track.c @@ -24,16 +24,27 @@ #include "bus-track.h" #include "bus-util.h" +struct track_item { + unsigned n_ref; + char *name; + sd_bus_slot *slot; +}; + 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; Hashmap *names; LIST_FIELDS(sd_bus_track, queue); Iterator iterator; - bool in_queue; - bool modified; + bool in_list:1; /* In bus->tracks? */ + bool in_queue:1; /* In bus->track_queue? */ + bool modified:1; + bool recursive:1; + + LIST_FIELDS(sd_bus_track, tracks); }; #define MATCH_PREFIX \ @@ -56,15 +67,45 @@ struct sd_bus_track { _x; \ }) +static struct track_item* track_item_free(struct track_item *i) { + + if (!i) + return NULL; + + sd_bus_slot_unref(i->slot); + free(i->name); + return mfree(i); +} + +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; + /* Already closed? */ + if (!track->in_list) + return; + LIST_PREPEND(queue, track->bus->track_queue, track); track->in_queue = true; } @@ -79,6 +120,24 @@ static void bus_track_remove_from_queue(sd_bus_track *track) { track->in_queue = false; } +static int bus_track_remove_name_fully(sd_bus_track *track, const char *name) { + struct track_item *i; + + assert(track); + assert(name); + + i = hashmap_remove(track->names, name); + if (!i) + return 0; + + track_item_free(i); + + bus_track_add_to_queue(track); + + track->modified = true; + return 1; +} + _public_ int sd_bus_track_new( sd_bus *bus, sd_bus_track **track, @@ -102,6 +161,9 @@ _public_ int sd_bus_track_new( t->userdata = userdata; t->bus = sd_bus_ref(bus); + LIST_PREPEND(tracks, bus->tracks, t); + t->in_list = true; + bus_track_add_to_queue(t); *track = t; @@ -121,7 +183,7 @@ _public_ sd_bus_track* sd_bus_track_ref(sd_bus_track *track) { } _public_ sd_bus_track* sd_bus_track_unref(sd_bus_track *track) { - const char *n; + struct track_item *i; if (!track) return NULL; @@ -133,15 +195,16 @@ _public_ sd_bus_track* sd_bus_track_unref(sd_bus_track *track) { return NULL; } - while ((n = hashmap_first_key(track->names))) - sd_bus_track_remove_name(track, n); + while ((i = hashmap_steal_first(track->names))) + track_item_free(i); + + if (track->in_list) + LIST_REMOVE(tracks, track->bus->tracks, track); bus_track_remove_from_queue(track); hashmap_free(track->names); sd_bus_unref(track->bus); - free(track); - - return NULL; + return mfree(track); } static int on_name_owner_changed(sd_bus_message *message, void *userdata, sd_bus_error *error) { @@ -156,49 +219,76 @@ static int on_name_owner_changed(sd_bus_message *message, void *userdata, sd_bus if (r < 0) return 0; - sd_bus_track_remove_name(track, name); + bus_track_remove_name_fully(track, name); return 0; } _public_ int sd_bus_track_add_name(sd_bus_track *track, const char *name) { - _cleanup_(sd_bus_slot_unrefp) sd_bus_slot *slot = NULL; - _cleanup_free_ char *n = NULL; + _cleanup_(track_item_freep) struct track_item *n = NULL; + struct track_item *i; const char *match; int r; assert_return(track, -EINVAL); assert_return(service_name_is_valid(name), -EINVAL); + i = hashmap_get(track->names, name); + if (i) { + if (track->recursive) { + unsigned k = track->n_ref + 1; + + if (k < track->n_ref) /* Check for overflow */ + return -EOVERFLOW; + + track->n_ref = k; + } + + bus_track_remove_from_queue(track); + return 0; + } + r = hashmap_ensure_allocated(&track->names, &string_hash_ops); if (r < 0) return r; - n = strdup(name); + n = new0(struct track_item, 1); if (!n) return -ENOMEM; + n->name = strdup(name); + if (!n->name) + return -ENOMEM; /* First, subscribe to this name */ - match = MATCH_FOR_NAME(n); - r = sd_bus_add_match(track->bus, &slot, match, on_name_owner_changed, track); - if (r < 0) + 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); + track->n_adding--; + if (r < 0) { + bus_track_add_to_queue(track); return r; + } - r = hashmap_put(track->names, n, slot); - if (r == -EEXIST) - return 0; - if (r < 0) + r = hashmap_put(track->names, n->name, n); + 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. */ - r = sd_bus_get_name_creds(track->bus, n, 0, NULL); + /* 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, n); + hashmap_remove(track->names, name); + bus_track_add_to_queue(track); return r; } + n->n_ref = 1; n = NULL; - slot = NULL; bus_track_remove_from_queue(track); track->modified = true; @@ -207,37 +297,48 @@ _public_ int sd_bus_track_add_name(sd_bus_track *track, const char *name) { } _public_ int sd_bus_track_remove_name(sd_bus_track *track, const char *name) { - _cleanup_(sd_bus_slot_unrefp) sd_bus_slot *slot = NULL; - _cleanup_free_ char *n = NULL; + struct track_item *i; assert_return(name, -EINVAL); - if (!track) + if (!track) /* Treat a NULL track object as an empty track object */ return 0; - slot = hashmap_remove2(track->names, (char*) name, (void**) &n); - if (!slot) - return 0; + if (!track->recursive) + return bus_track_remove_name_fully(track, name); - if (hashmap_isempty(track->names)) - bus_track_add_to_queue(track); + i = hashmap_get(track->names, name); + if (!i) + return -EUNATCH; + if (i->n_ref <= 0) + return -EUNATCH; - track->modified = true; + i->n_ref--; + + if (i->n_ref <= 0) + return bus_track_remove_name_fully(track, name); return 1; } _public_ unsigned sd_bus_track_count(sd_bus_track *track) { - if (!track) + + if (!track) /* Let's consider a NULL object equivalent to an empty object */ return 0; + /* This signature really should have returned an int, so that we can propagate errors. But well, ... Also, note + * that this returns the number of names being watched, and multiple references to the same name are not + * counted. */ + return hashmap_size(track->names); } _public_ const char* sd_bus_track_contains(sd_bus_track *track, const char *name) { - assert_return(track, NULL); assert_return(name, NULL); + if (!track) /* Let's consider a NULL object equivalent to an empty object */ + return NULL; + return hashmap_get(track->names, (void*) name) ? name : NULL; } @@ -273,6 +374,9 @@ _public_ int sd_bus_track_add_sender(sd_bus_track *track, sd_bus_message *m) { assert_return(track, -EINVAL); assert_return(m, -EINVAL); + if (sd_bus_message_get_bus(m) != track->bus) + return -EINVAL; + sender = sd_bus_message_get_sender(m); if (!sender) return -EINVAL; @@ -283,9 +387,14 @@ _public_ int sd_bus_track_add_sender(sd_bus_track *track, sd_bus_message *m) { _public_ int sd_bus_track_remove_sender(sd_bus_track *track, sd_bus_message *m) { const char *sender; - assert_return(track, -EINVAL); assert_return(m, -EINVAL); + if (!track) /* Treat a NULL track object as an empty track object */ + return 0; + + if (sd_bus_message_get_bus(m) != track->bus) + return -EINVAL; + sender = sd_bus_message_get_sender(m); if (!sender) return -EINVAL; @@ -303,7 +412,6 @@ void bus_track_dispatch(sd_bus_track *track) { int r; assert(track); - assert(track->in_queue); assert(track->handler); bus_track_remove_from_queue(track); @@ -319,6 +427,34 @@ void bus_track_dispatch(sd_bus_track *track) { sd_bus_track_unref(track); } +void bus_track_close(sd_bus_track *track) { + struct track_item *i; + + assert(track); + + /* Called whenever our bus connected is closed. If so, and our track object is non-empty, dispatch it + * immediately, as we are closing now, but first flush out all names. */ + + if (!track->in_list) + return; /* We already closed this one, don't close it again. */ + + /* Remember that this one is closed now */ + LIST_REMOVE(tracks, track->bus->tracks, track); + track->in_list = false; + + /* If there's no name in this one anyway, we don't have to dispatch */ + if (hashmap_isempty(track->names)) + return; + + /* Let's flush out all names */ + while ((i = hashmap_steal_first(track->names))) + track_item_free(i); + + /* Invoke handler */ + if (track->handler) + bus_track_dispatch(track); +} + _public_ void *sd_bus_track_get_userdata(sd_bus_track *track) { assert_return(track, NULL); @@ -335,3 +471,55 @@ _public_ void *sd_bus_track_set_userdata(sd_bus_track *track, void *userdata) { return ret; } + +_public_ int sd_bus_track_set_recursive(sd_bus_track *track, int b) { + assert_return(track, -EINVAL); + + if (track->recursive == !!b) + return 0; + + if (!hashmap_isempty(track->names)) + return -EBUSY; + + track->recursive = b; + return 0; +} + +_public_ int sd_bus_track_get_recursive(sd_bus_track *track) { + assert_return(track, -EINVAL); + + return track->recursive; +} + +_public_ int sd_bus_track_count_sender(sd_bus_track *track, sd_bus_message *m) { + const char *sender; + + assert_return(m, -EINVAL); + + if (!track) /* Let's consider a NULL object equivalent to an empty object */ + return 0; + + if (sd_bus_message_get_bus(m) != track->bus) + return -EINVAL; + + sender = sd_bus_message_get_sender(m); + if (!sender) + return -EINVAL; + + return sd_bus_track_count_name(track, sender); +} + +_public_ int sd_bus_track_count_name(sd_bus_track *track, const char *name) { + struct track_item *i; + + assert_return(service_name_is_valid(name), -EINVAL); + + if (!track) /* Let's consider a NULL object equivalent to an empty object */ + return 0; + + i = hashmap_get(track->names, name); + if (!i) + return 0; + + return i->n_ref; +} |