Ungrab brightness keys when not handling them

Closes #33

(cherry picked from commit 488d3471)

src/xfpm-backlight.c

@@ -281,6 +281,20 @@ xfpm_backlight_button_pressed_cb (XfpmButton *button, XfpmButtonKey type, XfpmBa
     xfpm_backlight_show (backlight, level);
 }
 
+static void
+xfpm_backlight_handle_brightness_keys_changed (XfpmBacklight *backlight)
+{
+  gboolean handle_keys = FALSE;
+
+  g_object_get (G_OBJECT (backlight->priv->conf),
+                HANDLE_BRIGHTNESS_KEYS, &handle_keys,
+                NULL);
+
+  XFPM_DEBUG ("handle_brightness_keys changed to %s", handle_keys ? "TRUE" : "FALSE");
+
+  xfpm_button_set_handle_brightness_keys (backlight->priv->button, handle_keys);
+}
+
 static void
 xfpm_backlight_brightness_on_ac_settings_changed (XfpmBacklight *backlight)
 {
@@ -438,6 +452,9 @@ xfpm_backlight_init (XfpmBacklight *backlight)
             BRIGHTNESS_SWITCH,
             backlight->priv->brightness_switch,
             NULL);
+    xfpm_button_set_handle_brightness_keys (backlight->priv->button, handle_keys);
+    g_signal_connect_object (backlight->priv->conf, "notify::" HANDLE_BRIGHTNESS_KEYS,
+                             G_CALLBACK (xfpm_backlight_handle_brightness_keys_changed), backlight, G_CONNECT_SWAPPED);
 
     g_signal_connect_object (backlight->priv->idle, "alarm-expired",
                              G_CALLBACK (xfpm_backlight_alarm_timeout_cb), backlight, 0);

src/xfpm-button.c

@@ -64,6 +64,7 @@ struct XfpmButtonPrivate
 {
   GdkScreen   *screen;
   GdkWindow   *window;
+  gboolean     handle_brightness_keys;
   guint16      mapped_buttons;
 };
 
@@ -182,6 +183,39 @@ xfpm_button_xevent_key (XfpmButton *button, guint keysym , XfpmButtonKey key)
   return TRUE;
 }
 
+static void
+xfpm_button_ungrab (XfpmButton *button, guint keysym, XfpmButtonKey key)
+{
+  Display *display;
+  GdkDisplay *gdisplay;
+  guint modmask = AnyModifier;
+  guint keycode = XKeysymToKeycode (gdk_x11_get_default_xdisplay(), keysym);
+
+  if (keycode == 0)
+  {
+    XFPM_DEBUG ("could not map keysym %x to keycode\n", keysym);
+    return;
+  }
+
+  display = gdk_x11_get_default_xdisplay ();
+  gdisplay = gdk_display_get_default ();
+
+  gdk_x11_display_error_trap_push (gdisplay);
+
+  XUngrabKey (display, keycode, modmask,
+              GDK_WINDOW_XID (button->priv->window));
+  XUngrabKey (display, keycode, LockMask | modmask,
+              GDK_WINDOW_XID (button->priv->window));
+
+  gdk_display_flush (gdisplay);
+  gdk_x11_display_error_trap_pop_ignored (gdisplay);
+
+  XFPM_DEBUG_ENUM (key, XFPM_TYPE_BUTTON_KEY, "Ungrabbed key %li ", (long int) keycode);
+
+  xfpm_key_map [key].key_code = 0;
+  xfpm_key_map [key].key = 0;
+}
+
 static void
 xfpm_button_setup (XfpmButton *button)
 {
@@ -204,11 +238,14 @@ xfpm_button_setup (XfpmButton *button)
   if ( xfpm_button_xevent_key (button, XF86XK_Sleep, BUTTON_SLEEP) )
     button->priv->mapped_buttons |= SLEEP_KEY;
 
-  if ( xfpm_button_xevent_key (button, XF86XK_MonBrightnessUp, BUTTON_MON_BRIGHTNESS_UP) )
-    button->priv->mapped_buttons |= BRIGHTNESS_KEY_UP;
+  if (button->priv->handle_brightness_keys)
+  {
+    if ( xfpm_button_xevent_key (button, XF86XK_MonBrightnessUp, BUTTON_MON_BRIGHTNESS_UP) )
+      button->priv->mapped_buttons |= BRIGHTNESS_KEY_UP;
 
-  if (xfpm_button_xevent_key (button, XF86XK_MonBrightnessDown, BUTTON_MON_BRIGHTNESS_DOWN) )
-    button->priv->mapped_buttons |= BRIGHTNESS_KEY_DOWN;
+    if (xfpm_button_xevent_key (button, XF86XK_MonBrightnessDown, BUTTON_MON_BRIGHTNESS_DOWN) )
+      button->priv->mapped_buttons |= BRIGHTNESS_KEY_DOWN;
+  }
 
   if (xfpm_button_xevent_key (button, XF86XK_Battery, BUTTON_BATTERY))
     button->priv->mapped_buttons |= BATTERY_KEY;
@@ -244,6 +281,7 @@ xfpm_button_init (XfpmButton *button)
 {
   button->priv = xfpm_button_get_instance_private (button);
 
+  button->priv->handle_brightness_keys = FALSE;
   button->priv->mapped_buttons = 0;
   button->priv->screen = NULL;
   button->priv->window = NULL;
@@ -282,3 +320,38 @@ xfpm_button_get_mapped (XfpmButton *button)
 
   return button->priv->mapped_buttons;
 }
+
+void
+xfpm_button_set_handle_brightness_keys (XfpmButton *button,
+                                        gboolean handle_brightness_keys)
+{
+  g_return_if_fail (XFPM_IS_BUTTON (button));
+
+  if (button->priv->handle_brightness_keys != handle_brightness_keys)
+  {
+    button->priv->handle_brightness_keys = handle_brightness_keys;
+
+    if (handle_brightness_keys)
+    {
+      if (xfpm_button_xevent_key (button, XF86XK_MonBrightnessUp, BUTTON_MON_BRIGHTNESS_UP))
+        button->priv->mapped_buttons |= BRIGHTNESS_KEY_UP;
+
+      if (xfpm_button_xevent_key (button, XF86XK_MonBrightnessDown, BUTTON_MON_BRIGHTNESS_DOWN))
+        button->priv->mapped_buttons |= BRIGHTNESS_KEY_DOWN;
+    }
+    else
+    {
+      if ((button->priv->mapped_buttons & BRIGHTNESS_KEY_UP) != 0)
+      {
+        xfpm_button_ungrab (button, XF86XK_MonBrightnessUp, BUTTON_MON_BRIGHTNESS_UP);
+        button->priv->mapped_buttons &= ~(BRIGHTNESS_KEY_UP);
+      }
+
+      if ((button->priv->mapped_buttons & BRIGHTNESS_KEY_DOWN) != 0)
+      {
+        xfpm_button_ungrab (button, XF86XK_MonBrightnessDown, BUTTON_MON_BRIGHTNESS_DOWN);
+        button->priv->mapped_buttons &= ~(BRIGHTNESS_KEY_DOWN);
+      }
+    }
+  }
+}

src/xfpm-button.h

@@ -50,6 +50,9 @@ GType                     xfpm_button_get_type             (void) G_GNUC_CONST;
 XfpmButton               *xfpm_button_new                  (void);
 guint16                   xfpm_button_get_mapped           (XfpmButton *button) G_GNUC_PURE;
 
+void                      xfpm_button_set_handle_brightness_keys (XfpmButton *button,
+                                                                  gboolean handle_brightness_keys);
+
 G_END_DECLS
 
 #endif /* __XFPM_BUTTON_H */