res_pjsip_mwi.c

	}
	return 0;
}

static int unsubscribe(void *obj, void *arg, int flags)
{
	struct mwi_subscription *mwi_sub = obj;

	ao2_callback(mwi_sub->stasis_subs, OBJ_UNLINK | OBJ_NODATA | OBJ_MULTIPLE, unsubscribe_stasis, NULL);

	return CMP_MATCH;
}

static void create_mwi_subscriptions(void)
{
	struct ao2_container *endpoints;
	struct ast_variable *var;

	var = ast_variable_new("mailboxes !=", "", "");

	endpoints = ast_sorcery_retrieve_by_fields(ast_sip_get_sorcery(), "endpoint",
		AST_RETRIEVE_FLAG_MULTIPLE, var);

	ast_variables_destroy(var);
	if (!endpoints) {
		return;
	}

	/* We remove all the old stasis subscriptions first before applying the new configuration. This
	 * prevents a situation where there might be multiple overlapping stasis subscriptions for an
	 * endpoint for mailboxes. Though there may be mailbox changes during the gap between unsubscribing
	 * and resubscribing, up-to-date mailbox state will be sent out to the endpoint when the
	 * new stasis subscription is established
	 */
	ao2_lock(unsolicited_mwi);
	ao2_callback(unsolicited_mwi, OBJ_NOLOCK | OBJ_UNLINK | OBJ_NODATA | OBJ_MULTIPLE, unsubscribe, NULL);
	ao2_callback(endpoints, OBJ_NODATA, create_mwi_subscriptions_for_endpoint, NULL);
	ao2_unlock(unsolicited_mwi);

	ao2_ref(endpoints, -1);
}

/*! \brief Function called to send MWI NOTIFY on any unsolicited mailboxes relating to this AOR */
static int send_contact_notify(void *obj, void *arg, int flags)
{
	struct mwi_subscription *mwi_sub = obj;
	const char *aor = arg;

	if (!mwi_sub->aors || !strstr(mwi_sub->aors, aor)) {
		return 0;
	}

	if (ast_sip_push_task(NULL, serialized_notify, ao2_bump(mwi_sub))) {
		ao2_ref(mwi_sub, -1);
	}

	return 0;
}

/*! \brief Function called when a contact is updated */
static void mwi_contact_updated(const void *object)
{
	char *id = ast_strdupa(ast_sorcery_object_get_id(object)), *aor = NULL;

	aor = strsep(&id, ";@");

	ao2_callback(unsolicited_mwi, OBJ_NODATA, send_contact_notify, aor);
}

/*! \brief Function called when a contact is added */
static void mwi_contact_added(const void *object)
{
	const struct ast_sip_contact *contact = object;
	struct ao2_iterator *mwi_subs;
	struct mwi_subscription *mwi_sub;
	const char *endpoint_id = ast_sorcery_object_get_id(contact->endpoint);

	if (ast_strlen_zero(contact->endpoint->subscription.mwi.mailboxes)) {
		return;
	}

	ao2_lock(unsolicited_mwi);

	mwi_subs = ao2_find(unsolicited_mwi, endpoint_id, OBJ_SEARCH_KEY | OBJ_MULTIPLE | OBJ_NOLOCK | OBJ_UNLINK);
	if (mwi_subs) {
		for (; (mwi_sub = ao2_iterator_next(mwi_subs)); ao2_cleanup(mwi_sub)) {
			unsubscribe(mwi_sub, NULL, 0);
		}
		ao2_iterator_destroy(mwi_subs);
	}

	create_mwi_subscriptions_for_endpoint(contact->endpoint, NULL, 0);

	ao2_unlock(unsolicited_mwi);

	mwi_contact_updated(object);
}

/*! \brief Observer for contacts so unsolicited MWI is sent when a contact changes */
static const struct ast_sorcery_observer mwi_contact_observer = {
	.created = mwi_contact_added,
	.updated = mwi_contact_updated,
};

/*! \brief Task invoked to send initial MWI NOTIFY for unsolicited */
static int send_initial_notify_all(void *obj)
{
	ao2_callback(unsolicited_mwi, OBJ_NODATA, send_notify, NULL);

	return 0;
}

/*! \brief Event callback which fires initial unsolicited MWI NOTIFY messages when we're fully booted */
static void mwi_startup_event_cb(void *data, struct stasis_subscription *sub, struct stasis_message *message)
{
	struct ast_json_payload *payload;
	const char *type;

	if (stasis_message_type(message) != ast_manager_get_generic_type()) {
		return;
	}

	payload = stasis_message_data(message);
	type = ast_json_string_get(ast_json_object_get(payload->json, "type"));

	if (strcmp(type, "FullyBooted")) {
		return;
	}

	ast_sip_push_task(NULL, send_initial_notify_all, NULL);

	stasis_unsubscribe(sub);
}

static void global_loaded(const char *object_type)
{
	ast_free(default_voicemail_extension);
	default_voicemail_extension = ast_sip_get_default_voicemail_extension();
}

static struct ast_sorcery_observer global_observer = {
	.loaded = global_loaded,
};

static int reload(void)
{
	create_mwi_subscriptions();
	return 0;
}

static int load_module(void)
{
	CHECK_PJSIP_MODULE_LOADED();

	if (ast_sip_register_subscription_handler(&mwi_handler)) {
		return AST_MODULE_LOAD_DECLINE;
	}

	unsolicited_mwi = ao2_container_alloc(MWI_BUCKETS, mwi_sub_hash, mwi_sub_cmp);
	if (!unsolicited_mwi) {
		ast_sip_unregister_subscription_handler(&mwi_handler);
		return AST_MODULE_LOAD_DECLINE;
	}

	create_mwi_subscriptions();
	ast_sorcery_observer_add(ast_sip_get_sorcery(), "contact", &mwi_contact_observer);
	ast_sorcery_observer_add(ast_sip_get_sorcery(), "global", &global_observer);
	ast_sorcery_reload_object(ast_sip_get_sorcery(), "global");

	if (ast_test_flag(&ast_options, AST_OPT_FLAG_FULLY_BOOTED)) {
		ast_sip_push_task(NULL, send_initial_notify_all, NULL);
	} else {
		stasis_subscribe_pool(ast_manager_get_topic(), mwi_startup_event_cb, NULL);
	}

	return AST_MODULE_LOAD_SUCCESS;
}

static int unload_module(void)
{
	ao2_callback(unsolicited_mwi, OBJ_UNLINK | OBJ_NODATA | OBJ_MULTIPLE, unsubscribe, NULL);
	ao2_ref(unsolicited_mwi, -1);
	ast_sorcery_observer_remove(ast_sip_get_sorcery(), "global", &global_observer);
	ast_sorcery_observer_remove(ast_sip_get_sorcery(), "contact", &mwi_contact_observer);
	ast_sip_unregister_subscription_handler(&mwi_handler);
	ast_free(default_voicemail_extension);
	return 0;
}

AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_LOAD_ORDER, "PJSIP MWI resource",
	.support_level = AST_MODULE_SUPPORT_CORE,
	.load = load_module,
	.unload = unload_module,
	.reload = reload,
	.load_pri = AST_MODPRI_CHANNEL_DEPEND,
);