1 files changed, 104 insertions, 0 deletions
diff --git a/widget/gtk/ScreenHelperGTK.h b/widget/gtk/ScreenHelperGTK.h
new file mode 100644
index 0000000000..2b162903aa
--- /dev/null
+++ b/widget/gtk/ScreenHelperGTK.h
@@ -0,0 +1,104 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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_widget_gtk_ScreenHelperGTK_h
+#define mozilla_widget_gtk_ScreenHelperGTK_h
+
+#include "mozilla/widget/ScreenManager.h"
+
+#include "gdk/gdk.h"
+#ifdef MOZ_X11
+#  include <X11/Xlib.h>
+#  include "X11UndefineNone.h"
+#endif
+
+class nsWindow;
+struct wl_registry;
+
+namespace mozilla {
+namespace widget {
+
+class ScreenGetter {
+ public:
+  ScreenGetter() = default;
+  virtual ~ScreenGetter(){};
+
+  virtual void Init(){};
+
+  virtual void RefreshScreens(){};
+  virtual RefPtr<widget::Screen> GetScreenForWindow(nsWindow* aWindow) {
+    return nullptr;
+  }
+};
+
+class ScreenGetterGtk : public ScreenGetter {
+ public:
+  ScreenGetterGtk();
+  ~ScreenGetterGtk();
+
+  void Init();
+
+#ifdef MOZ_X11
+  Atom NetWorkareaAtom() { return mNetWorkareaAtom; }
+#endif
+
+  // For internal use from signal callback functions
+  void RefreshScreens();
+
+ private:
+  GdkWindow* mRootWindow;
+#ifdef MOZ_X11
+  Atom mNetWorkareaAtom;
+#endif
+};
+
+class ScreenGetterWayland;
+struct MonitorConfig;
+
+#ifdef MOZ_WAYLAND
+class ScreenGetterWayland : public ScreenGetter {
+ public:
+  ScreenGetterWayland();
+  ~ScreenGetterWayland();
+
+  void Init();
+
+  MonitorConfig* AddMonitorConfig(int aId);
+  bool RemoveMonitorConfig(int aId);
+  already_AddRefed<Screen> MakeScreenWayland(gint aMonitor);
+
+  RefPtr<widget::Screen> GetScreenForWindow(nsWindow* aWindow);
+
+  // For internal use from signal callback functions
+  void RefreshScreens();
+
+ private:
+  int GetMonitorForWindow(nsWindow* aWindow);
+  bool MonitorUsesNonIntegerScale(int aMonitor);
+
+ private:
+  wl_registry* mRegistry = nullptr;
+  // We use UniquePtr<> here to ensure that MonitorConfig is heap-allocated
+  // so it's not invalidated by any change to mMonitors that could happen in the
+  // meantime.
+  AutoTArray<UniquePtr<MonitorConfig>, 4> mMonitors;
+  AutoTArray<RefPtr<Screen>, 4> mScreenList;
+};
+#endif
+
+class ScreenHelperGTK final : public ScreenManager::Helper {
+ public:
+  ScreenHelperGTK();
+  ~ScreenHelperGTK();
+
+  static gint GetGTKMonitorScaleFactor(gint aMonitorNum = 0);
+  static RefPtr<widget::Screen> GetScreenForWindow(nsWindow* aWindow);
+};
+
+}  // namespace widget
+}  // namespace mozilla
+
+#endif  // mozilla_widget_gtk_ScreenHelperGTK_h