1 files changed, 84 insertions, 0 deletions
diff --git a/widget/gtk/WindowSurfaceWaylandMultiBuffer.h b/widget/gtk/WindowSurfaceWaylandMultiBuffer.h
new file mode 100644
index 0000000000..e14a626de0
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+++ b/widget/gtk/WindowSurfaceWaylandMultiBuffer.h
@@ -0,0 +1,84 @@
+/* -*- Mode: C++; tab-width: 4; 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_WIDGET_GTK_WINDOW_SURFACE_WAYLAND_MULTI_BUFFER_H
+#define _MOZILLA_WIDGET_GTK_WINDOW_SURFACE_WAYLAND_MULTI_BUFFER_H
+
+#include "mozilla/gfx/2D.h"
+#include "mozilla/gfx/Types.h"
+#include "mozilla/Mutex.h"
+#include "nsTArray.h"
+#include "nsWaylandDisplay.h"
+#include "nsWindow.h"
+#include "WaylandBuffer.h"
+#include "WindowSurface.h"
+
+namespace mozilla::widget {
+
+using gfx::DrawTarget;
+
+// WindowSurfaceWaylandMB is an abstraction for wl_surface
+// and related management
+class WindowSurfaceWaylandMB : public WindowSurface {
+ public:
+  WindowSurfaceWaylandMB(RefPtr<nsWindow> aWindow,
+                         GtkCompositorWidget* aCompositorWidget);
+  ~WindowSurfaceWaylandMB() = default;
+
+  // Lock() / Commit() are called by gecko when Firefox
+  // wants to display something. Lock() returns a DrawTarget
+  // where gecko paints. When gecko is done it calls Commit()
+  // and we try to send the DrawTarget (backed by wl_buffer)
+  // to wayland compositor.
+  //
+  // If we fail (wayland compositor is busy,
+  // wl_surface is not created yet) we queue the painting
+  // and we send it to wayland compositor in FrameCallbackHandler()/
+  // FlushPendingCommits().
+  already_AddRefed<DrawTarget> Lock(
+      const LayoutDeviceIntRegion& aInvalidRegion) override;
+  void Commit(const LayoutDeviceIntRegion& aInvalidRegion) final;
+
+ private:
+  void Commit(const MutexAutoLock& aProofOfLock,
+              const LayoutDeviceIntRegion& aInvalidRegion);
+  RefPtr<WaylandBufferSHM> ObtainBufferFromPool(
+      const MutexAutoLock& aProofOfLock, const LayoutDeviceIntSize& aSize);
+  void ReturnBufferToPool(const MutexAutoLock& aProofOfLock,
+                          const RefPtr<WaylandBufferSHM>& aBuffer);
+  void EnforcePoolSizeLimit(const MutexAutoLock& aProofOfLock);
+  void CollectPendingSurfaces(const MutexAutoLock& aProofOfLock);
+  void HandlePartialUpdate(const MutexAutoLock& aProofOfLock,
+                           const LayoutDeviceIntRegion& aInvalidRegion);
+  void IncrementBufferAge(const MutexAutoLock& aProofOfLock);
+  // Return true if window size was updated.
+  bool MaybeUpdateWindowSize();
+
+  mozilla::Mutex mSurfaceLock MOZ_UNANNOTATED;
+
+  RefPtr<nsWindow> mWindow;
+  // WindowSurfaceWaylandMB is owned by GtkCompositorWidget so we can't
+  // reference it.
+  GtkCompositorWidget* mCompositorWidget;
+  LayoutDeviceIntSize mWindowSize;
+
+  RefPtr<WaylandBufferSHM> mInProgressBuffer;
+  RefPtr<WaylandBufferSHM> mFrontBuffer;
+  LayoutDeviceIntRegion mFrontBufferInvalidRegion;
+
+  // buffer pool
+  nsTArray<RefPtr<WaylandBufferSHM>> mInUseBuffers;
+  nsTArray<RefPtr<WaylandBufferSHM>> mPendingBuffers;
+  nsTArray<RefPtr<WaylandBufferSHM>> mAvailableBuffers;
+
+  // delayed commits
+  bool mFrameInProcess;
+  bool mCallbackRequested;
+};
+
+}  // namespace mozilla::widget
+
+#endif  // _MOZILLA_WIDGET_GTK_WINDOW_SURFACE_WAYLAND_MULTI_BUFFER_H