miracled: implement PropertiesChanged signals

We need to send PropertiesChanged signals whenever we change properties
that are annotated as such.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>

src/miracle.h

@@ -23,9 +23,11 @@
  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
+#include <alloca.h>
 #include <errno.h>
 #include <stdbool.h>
 #include <stdlib.h>
+#include <stdarg.h>
 #include <systemd/sd-bus.h>
 #include "shl_log.h"
 #include "shl_macro.h"
@@ -94,4 +96,29 @@ static inline int bus_message_read_basic_variant(sd_bus_message *m,
 	return 0;
 }
 
+#define strv_from_stdarg_alloca(first) ({ \
+		char **_l; \
+		if (!first) { \
+			_l = (char**)&first; \
+		} else { \
+			unsigned _n; \
+			va_list _ap; \
+			_n = 1; \
+			va_start(_ap, first); \
+			while (va_arg(_ap, char*)) \
+				_n++; \
+			va_end(_ap); \
+			_l = alloca(sizeof(char*) * (_n + 1)); \
+			_l[_n = 0] = (char*)first; \
+			va_start(_ap, first); \
+			for (;;) { \
+				_l[++_n] = va_arg(_ap, char*); \
+				if (!_l[_n]) \
+					break; \
+			} \
+			va_end(_ap); \
+		} \
+		_l; \
+	})
+
 #endif /* MIRACLE_H */

src/miracled-dbus.c

@@ -264,6 +264,25 @@ static int peer_dbus_find(sd_bus *bus,
 	return 1;
 }
 
+void peer_dbus_properties_changed(struct peer *p, const char *prop, ...)
+{
+	_cleanup_free_ char *path = NULL;
+	char **strv;
+	int r;
+
+	path = shl_strcat("/org/freedesktop/miracle/peer/", p->name);
+	if (!path)
+		return log_vENOMEM();
+
+	strv = strv_from_stdarg_alloca(prop);
+	r = sd_bus_emit_properties_changed_strv(p->l->m->bus,
+						path,
+						"org.freedesktop.miracle.Peer",
+						strv);
+	if (r < 0)
+		log_vERR(r);
+}
+
 /*
  * Link DBus
  */
@@ -407,6 +426,25 @@ static int link_dbus_find(sd_bus *bus,
 	return 1;
 }
 
+void link_dbus_properties_changed(struct link *l, const char *prop, ...)
+{
+	_cleanup_free_ char *path = NULL;
+	char **strv;
+	int r;
+
+	path = shl_strcat("/org/freedesktop/miracle/link/", l->name);
+	if (!path)
+		return log_vENOMEM();
+
+	strv = strv_from_stdarg_alloca(prop);
+	r = sd_bus_emit_properties_changed_strv(l->m->bus,
+						path,
+						"org.freedesktop.miracle.Link",
+						strv);
+	if (r < 0)
+		log_vERR(r);
+}
+
 /*
  * Manager DBus
  */

src/miracled-link.c

@@ -301,6 +301,7 @@ int link_set_friendly_name(struct link *l, const char *name)
 
 	free(l->friendly_name);
 	l->friendly_name = dup;
+	link_dbus_properties_changed(l, "Name", NULL);
 
 	return 0;
 }

src/miracled-peer.c

@@ -204,8 +204,10 @@ void peer_process_wifi(struct peer *p, struct wifi_event *ev)
 	case WIFI_DEV_PROVISION:
 		break;
 	case WIFI_DEV_CONNECT:
+		peer_dbus_properties_changed(p, "Connected", NULL);
 		break;
 	case WIFI_DEV_DISCONNECT:
+		peer_dbus_properties_changed(p, "Connected", NULL);
 		break;
 	default:
 		log_debug("unhandled WIFI event: %u", ev->type);

src/miracled.h

@@ -138,4 +138,9 @@ void manager_dbus_disconnect(struct manager *m);
 struct link *manager_find_link(struct manager *m, const char *name);
 struct peer *manager_find_peer(struct manager *m, const char *name);
 
+/* dbus */
+
+void peer_dbus_properties_changed(struct peer *p, const char *prop, ...);
+void link_dbus_properties_changed(struct link *l, const char *prop, ...);
+
 #endif /* MIRACLED_H */