1 files changed, 132 insertions, 0 deletions
diff --git a/layout/base/nsGenConList.h b/layout/base/nsGenConList.h
new file mode 100644
index 0000000000..271c426080
--- /dev/null
+++ b/layout/base/nsGenConList.h
@@ -0,0 +1,132 @@
+/* -*- 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/. */
+
+/* base class for nsCounterList and nsQuoteList */
+
+#ifndef nsGenConList_h___
+#define nsGenConList_h___
+
+#include "mozilla/FunctionRef.h"
+#include "mozilla/LinkedList.h"
+#include "nsStyleStruct.h"
+#include "nsCSSPseudoElements.h"
+#include "nsTextNode.h"
+#include <functional>
+
+class nsGenConList;
+class nsIFrame;
+
+struct nsGenConNode : public mozilla::LinkedListElement<nsGenConNode> {
+  using StyleContentType = mozilla::StyleContentItem::Tag;
+
+  // The wrapper frame for all of the pseudo-element's content.  This
+  // frame generally has useful style data and has the
+  // NS_FRAME_GENERATED_CONTENT bit set (so we use it to track removal),
+  // but does not necessarily for |nsCounterChangeNode|s.
+  nsIFrame* mPseudoFrame;
+
+  // Index within the list of things specified by the 'content' property,
+  // which is needed to do 'content: open-quote open-quote' correctly,
+  // and needed for similar cases for counters.
+  const int32_t mContentIndex;
+
+  // null for:
+  //  * content: no-open-quote / content: no-close-quote
+  //  * counter nodes for increments and resets
+  RefPtr<nsTextNode> mText;
+
+  explicit nsGenConNode(int32_t aContentIndex)
+      : mPseudoFrame(nullptr), mContentIndex(aContentIndex) {}
+
+  /**
+   * Finish initializing the generated content node once we know the
+   * relevant text frame. This must be called just after
+   * the textframe has been initialized. This need not be called at all
+   * for nodes that don't generate text. This will generally set the
+   * mPseudoFrame, insert the node into aList, and set aTextFrame up
+   * with the correct text.
+   * @param aList the list the node belongs to
+   * @param aPseudoFrame the :before or :after frame
+   * @param aTextFrame the textframe where the node contents will render
+   * @return true iff this marked the list dirty
+   */
+  virtual bool InitTextFrame(nsGenConList* aList, nsIFrame* aPseudoFrame,
+                             nsIFrame* aTextFrame) {
+    mPseudoFrame = aPseudoFrame;
+    CheckFrameAssertions();
+    return false;
+  }
+
+  virtual ~nsGenConNode() = default;  // XXX Avoid, perhaps?
+
+ protected:
+  void CheckFrameAssertions();
+};
+
+class nsGenConList {
+ protected:
+  mozilla::LinkedList<nsGenConNode> mList;
+  uint32_t mSize;
+
+ public:
+  nsGenConList() : mSize(0), mLastInserted(nullptr) {}
+  ~nsGenConList() { Clear(); }
+  void Clear();
+  static nsGenConNode* Next(nsGenConNode* aNode) {
+    MOZ_ASSERT(aNode, "aNode cannot be nullptr!");
+    return aNode->getNext();
+  }
+  static nsGenConNode* Prev(nsGenConNode* aNode) {
+    MOZ_ASSERT(aNode, "aNode cannot be nullptr!");
+    return aNode->getPrevious();
+  }
+  void Insert(nsGenConNode* aNode);
+
+  // Destroy all nodes with aFrame as parent. Returns true if some nodes
+  // have been destroyed; otherwise false.
+  bool DestroyNodesFor(nsIFrame* aFrame);
+
+  // Return the first node for aFrame on this list, or nullptr.
+  nsGenConNode* GetFirstNodeFor(nsIFrame* aFrame) const {
+    return mNodes.Get(aFrame);
+  }
+
+  // Return true if |aNode1| is after |aNode2|.
+  static bool NodeAfter(const nsGenConNode* aNode1, const nsGenConNode* aNode2);
+
+  // Find the first element in the list for which the given comparator returns
+  // true. This does a binary search on the list contents.
+  nsGenConNode* BinarySearch(
+      const mozilla::FunctionRef<bool(nsGenConNode*)>& aIsAfter);
+
+  nsGenConNode* GetLast() { return mList.getLast(); }
+
+  bool IsFirst(nsGenConNode* aNode) {
+    MOZ_ASSERT(aNode, "aNode cannot be nullptr!");
+    return aNode == mList.getFirst();
+  }
+
+  bool IsLast(nsGenConNode* aNode) {
+    MOZ_ASSERT(aNode, "aNode cannot be nullptr!");
+    return aNode == mList.getLast();
+  }
+
+ private:
+  void Destroy(nsGenConNode* aNode) {
+    MOZ_ASSERT(aNode, "aNode cannot be nullptr!");
+    delete aNode;
+    mSize--;
+  }
+
+  // Map from frame to the first nsGenConNode of it in the list.
+  nsTHashMap<nsPtrHashKey<nsIFrame>, nsGenConNode*> mNodes;
+
+  // A weak pointer to the node most recently inserted, used to avoid repeated
+  // list traversals in Insert().
+  nsGenConNode* mLastInserted;
+};
+
+#endif /* nsGenConList_h___ */