1 files changed, 84 insertions, 0 deletions
diff --git a/layout/generic/nsPageContentFrame.h b/layout/generic/nsPageContentFrame.h
new file mode 100644
index 0000000000..3f67262eef
--- /dev/null
+++ b/layout/generic/nsPageContentFrame.h
@@ -0,0 +1,84 @@
+/* -*- 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 nsPageContentFrame_h___
+#define nsPageContentFrame_h___
+
+#include "mozilla/Attributes.h"
+#include "mozilla/ViewportFrame.h"
+
+class nsPageFrame;
+class nsSharedPageData;
+
+namespace mozilla {
+class PresShell;
+}  // namespace mozilla
+
+// Page content frame class. Represents a page's content, in paginated mode.
+class nsPageContentFrame final : public mozilla::ViewportFrame {
+ public:
+  NS_DECL_FRAMEARENA_HELPERS(nsPageContentFrame)
+
+  friend nsPageContentFrame* NS_NewPageContentFrame(
+      mozilla::PresShell* aPresShell, ComputedStyle* aStyle,
+      already_AddRefed<const nsAtom> aPageName);
+  friend class nsPageFrame;
+
+  // nsIFrame
+  void Reflow(nsPresContext* aPresContext, ReflowOutput& aReflowOutput,
+              const ReflowInput& aReflowInput,
+              nsReflowStatus& aStatus) override;
+
+  bool IsFrameOfType(uint32_t aFlags) const override {
+    return ViewportFrame::IsFrameOfType(
+        aFlags & ~(nsIFrame::eCanContainOverflowContainers));
+  }
+
+  const nsAtom* GetPageName() const { return mPageName; }
+
+  void SetSharedPageData(nsSharedPageData* aPD) { mPD = aPD; }
+
+  ComputeTransformFunction GetTransformGetter() const override;
+  void BuildDisplayList(nsDisplayListBuilder*,
+                        const nsDisplayListSet&) override;
+
+  /**
+   * Return our canvas frame.
+   */
+  void AppendDirectlyOwnedAnonBoxes(nsTArray<OwnedAnonBox>& aResult) override;
+
+  void EnsurePageName();
+
+  // The default implementation of FirstContinuation in nsSplittableFrame is
+  // implemented in linear time, walking back through the linked list of
+  // continuations via mPrevContinuation.
+  // For nsPageContentFrames, we can find the first continuation through the
+  // frame tree structure in constant time.
+  nsIFrame* FirstContinuation() const final;
+
+#ifdef DEBUG_FRAME_DUMP
+  // Debugging
+  nsresult GetFrameName(nsAString& aResult) const override;
+  void ExtraContainerFrameInfo(nsACString& aTo) const override;
+#endif
+
+ protected:
+  explicit nsPageContentFrame(ComputedStyle* aStyle,
+                              nsPresContext* aPresContext,
+                              already_AddRefed<const nsAtom> aPageName)
+      : ViewportFrame(aStyle, aPresContext, kClassID), mPageName(aPageName) {}
+
+  RefPtr<const nsAtom> mPageName;
+
+  // Note: this will be set before reflow, and it's strongly owned by our
+  // nsPageSequenceFrame, which outlives us.
+  nsSharedPageData* mPD = nullptr;
+
+  // The combined InkOverflow from the previous and current page that does not
+  // yet have space allocated for it.
+  nscoord mRemainingOverflow = 0;
+};
+
+#endif /* nsPageContentFrame_h___ */