1 files changed, 42 insertions, 0 deletions
diff --git a/gfx/layers/apz/util/TouchActionHelper.h b/gfx/layers/apz/util/TouchActionHelper.h
new file mode 100644
index 000000000..1dacfd4c0
--- /dev/null
+++ b/gfx/layers/apz/util/TouchActionHelper.h
@@ -0,0 +1,42 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef __mozilla_layers_TouchActionHelper_h__
+#define __mozilla_layers_TouchActionHelper_h__
+
+#include "mozilla/layers/APZUtils.h" // for TouchBehaviorFlags
+
+class nsIFrame;
+class nsIWidget;
+
+namespace mozilla {
+namespace layers {
+
+/*
+ * Helper class to figure out the allowed touch behavior for frames, as per
+ * the touch-action spec.
+ */
+class TouchActionHelper
+{
+private:
+  static void UpdateAllowedBehavior(uint32_t aTouchActionValue,
+                                    bool aConsiderPanning,
+                                    TouchBehaviorFlags& aOutBehavior);
+
+public:
+  /*
+   * Performs hit testing on content, finds frame that corresponds to the aPoint and retrieves
+   * touch-action css property value from it according the rules specified in the spec:
+   * http://www.w3.org/TR/pointerevents/#the-touch-action-css-property.
+   */
+  static TouchBehaviorFlags GetAllowedTouchBehavior(nsIWidget* aWidget,
+                                                    nsIFrame* aRootFrame,
+                                                    const LayoutDeviceIntPoint& aPoint);
+};
+
+} // namespace layers
+} // namespace mozilla
+
+#endif /*__mozilla_layers_TouchActionHelper_h__ */