service: Update nameservers automatically

Automatically update nameserver information when they are appended
or removed to the resolver code so that nameservers for IPv6 can be
signalled after IPv4 has moved the service to state 'ready'. Create
a zero second timeout so that nameservers can be appended or removed
in a loop one by one with only one D-Bus PropertyChanged signal
being sent.

Verify that the service is either connected or the nameservers have
been removed when the service is inactive before sending the
PropertyChanged signal.

connman/src/service.c

@@ -322,6 +322,7 @@ struct connman_service {
 	char **nameservers;
 	char **nameservers_config;
 	char **nameservers_auto;
+	int nameservers_timeout;
 	char **domains;
 	char *hostname;
 	char *domainname;
@@ -387,6 +388,7 @@ static struct connman_ipconfig *create_ip4config(struct connman_service *service
 		int index, enum connman_ipconfig_method method);
 static struct connman_ipconfig *create_ip6config(struct connman_service *service,
 		int index);
+static void dns_changed(struct connman_service *service);
 
 static void vpn_auto_connect(void);
 static bool is_connecting(struct connman_service *service);
@@ -1496,6 +1498,24 @@ static bool is_connected_state(const struct connman_service *service,
 	return false;
 }
 
+static bool is_idle(struct connman_service *service)
+{
+	switch (service->state) {
+	case CONNMAN_SERVICE_STATE_IDLE:
+	case CONNMAN_SERVICE_STATE_DISCONNECT:
+	case CONNMAN_SERVICE_STATE_FAILURE:
+		return true;
+	case CONNMAN_SERVICE_STATE_UNKNOWN:
+	case CONNMAN_SERVICE_STATE_ASSOCIATION:
+	case CONNMAN_SERVICE_STATE_CONFIGURATION:
+	case CONNMAN_SERVICE_STATE_READY:
+	case CONNMAN_SERVICE_STATE_ONLINE:
+		break;
+	}
+
+	return false;
+}
+
 static bool is_connecting(struct connman_service *service)
 {
 	return is_connecting_state(service, service->state);
@@ -1506,6 +1526,29 @@ static bool is_connected(struct connman_service *service)
 	return is_connected_state(service, service->state);
 }
 
+
+static int nameservers_changed_cb(void *user_data)
+{
+	struct connman_service *service = user_data;
+
+	DBG("service %p", service);
+
+	service->nameservers_timeout = 0;
+	if ((is_idle(service) && !service->nameservers) ||
+			is_connected(service))
+		dns_changed(service);
+
+	return FALSE;
+}
+
+static void nameservers_changed(struct connman_service *service)
+{
+	if (!service->nameservers_timeout)
+		service->nameservers_timeout = g_timeout_add_seconds(0,
+							nameservers_changed_cb,
+							service);
+}
+
 static bool nameserver_available(struct connman_service *service,
 				enum connman_ipconfig_type type,
 				const char *ns)
@@ -1585,7 +1628,7 @@ static int nameserver_add(struct connman_service *service,
 			enum connman_ipconfig_type type,
 			const char *nameserver)
 {
-	int index;
+	int index, ret;
 
 	if (!nameserver_available(service, type, nameserver))
 		return 0;
@@ -1594,7 +1637,11 @@ static int nameserver_add(struct connman_service *service,
 	if (index < 0)
 		return -ENXIO;
 
-	return connman_resolver_append(index, NULL, nameserver);
+	ret = connman_resolver_append(index, NULL, nameserver);
+	if (ret >= 0)
+		nameservers_changed(service);
+
+	return ret;
 }
 
 static int nameserver_add_all(struct connman_service *service,
@@ -1628,7 +1675,7 @@ static int nameserver_remove(struct connman_service *service,
 			enum connman_ipconfig_type type,
 			const char *nameserver)
 {
-	int index;
+	int index, ret;
 
 	if (!nameserver_available(service, type, nameserver))
 		return 0;
@@ -1637,7 +1684,11 @@ static int nameserver_remove(struct connman_service *service,
 	if (index < 0)
 		return -ENXIO;
 
-	return connman_resolver_remove(index, NULL, nameserver);
+	ret = connman_resolver_remove(index, NULL, nameserver);
+	if (ret >= 0)
+		nameservers_changed(service);
+
+	return ret;
 }
 
 static int nameserver_remove_all(struct connman_service *service,
@@ -1713,6 +1764,8 @@ int __connman_service_nameserver_append(struct connman_service *service,
 		nameserver_add(service, CONNMAN_IPCONFIG_TYPE_ALL, nameserver);
 	}
 
+	nameservers_changed(service);
+
 	searchdomain_add_all(service);
 
 	return 0;
@@ -6427,6 +6480,11 @@ static void service_free(gpointer user_data)
 
 	reply_pending(service, ENOENT);
 
+	if (service->nameservers_timeout) {
+		g_source_remove(service->nameservers_timeout);
+		dns_changed(service);
+	}
+
 	__connman_notifier_service_remove(service);
 	/* In our fork, service_schedule_removed() is called by
 	 * service_removed() when the service is being removed
@@ -7530,7 +7588,6 @@ static int service_indicate_state(struct connman_service *service)
 		update_modified(service);
 		service_save(service);
 
-		dns_changed(service);
 		domain_changed(service);
 		proxy_changed(service);
 
@@ -7564,7 +7621,6 @@ static int service_indicate_state(struct connman_service *service)
 
 		__connman_wpad_stop(service);
 
-		dns_changed(service);
 		domain_changed(service);
 		proxy_changed(service);