[plugins] Added org.sailfishos.nfc.Tag.Removed signal

It replaces PresentChanged signal which was never issued in the
first place (DBusServiceTag was getting deleted before it had a
chance to issue this signal), so this can't really be considered
an API break. Still, the interface version is bumped, so that
support for the new signal could be determined at runtime by
those clients which depend on it.

The new Removed signal is always issued when DBusServiceTag is
deleted. This way, D-Bus client won't have to watch the adapter
too in order to be notified when the tag is gone.

plugins/dbus_service/dbus_service_tag.c

@@ -1,6 +1,6 @@
 /*
- * Copyright (C) 2018 Jolla Ltd.
- * Copyright (C) 2018 Slava Monich <slava.monich@jolla.com>
+ * Copyright (C) 2018-2019 Jolla Ltd.
+ * Copyright (C) 2018-2019 Slava Monich <slava.monich@jolla.com>
  *
  * You may use this file under the terms of BSD license as follows:
  *
@@ -14,8 +14,8 @@
  *      notice, this list of conditions and the following disclaimer in the
  *      documentation and/or other materials provided with the distribution.
  *   3. Neither the names of the copyright holders nor the names of its
- *      contributors may be used to endorse or promote products derived from
- *      this software without specific prior written permission.
+ *      contributors may be used to endorse or promote products derived
+ *      from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
@@ -43,7 +43,6 @@
 
 enum {
     EVENT_INITIALIZED,
-    EVENT_GONE,
     EVENT_COUNT
 };
 
@@ -93,7 +92,7 @@ struct dbus_service_tag {
 };
 
 #define NFC_DBUS_TAG_INTERFACE "org.sailfishos.nfc.Tag"
-#define NFC_DBUS_TAG_INTERFACE_VERSION  (1)
+#define NFC_DBUS_TAG_INTERFACE_VERSION  (2)
 
 static const char* const dbus_service_tag_default_interfaces[] = {
     NFC_DBUS_TAG_INTERFACE, NULL
@@ -259,18 +258,6 @@ dbus_service_tag_initialized(
     dbus_service_tag_complete_pending_calls(self);
 }
 
-static
-void
-dbus_service_tag_gone(
-    NfcTag* tag,
-    void* user_data)
-{
-    DBusServiceTag* self = user_data;
-
-    GASSERT(!tag->present);
-    org_sailfishos_nfc_tag_emit_present_changed(self->iface, tag->present);
-}
-
 /*==========================================================================*
  * D-Bus calls
  *==========================================================================*/
@@ -496,11 +483,6 @@ dbus_service_tag_new(
     self->pool = gutil_idle_pool_new();
     self->iface = org_sailfishos_nfc_tag_skeleton_new();
 
-    /* NfcTag events */
-    self->event_id[EVENT_GONE] =
-        nfc_tag_add_gone_handler(tag,
-            dbus_service_tag_gone, self);
-
     /* D-Bus calls */
     self->call_id[CALL_GET_ALL] =
         g_signal_connect(self->iface, "handle-get-all",
@@ -556,6 +538,7 @@ dbus_service_tag_free(
 {
     if (self) {
         GDEBUG("Removing D-Bus object %s", self->path);
+        org_sailfishos_nfc_tag_emit_removed(self->iface);
         g_dbus_interface_skeleton_unexport(G_DBUS_INTERFACE_SKELETON
             (self->iface));
         dbus_service_tag_free_unexported(self);

plugins/dbus_service/org.sailfishos.nfc.Tag.xml

@@ -54,8 +54,6 @@
     </method>
     <method name="Deactivate"/>
     <!-- Signals -->  
-    <signal name="PresentChanged">
-      <arg name="present" type="b"/>
-    </signal>
+    <signal name="Removed"/>
   </interface>
 </node>