dom/base/AbstractRange.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_AbstractRange_h
   8 #define mozilla_dom_AbstractRange_h
   9
  10 #include "mozilla/RangeBoundary.h"
  11 #include "mozilla/dom/Document.h"
  12 #include "nsIContent.h"
  13 #include "nsINode.h"
  14 #include "nsWrapperCache.h"
  15
  16 namespace mozilla {
  17 namespace dom {
  18
  19 class AbstractRange : public nsISupports, public nsWrapperCache {
  20  protected:
  21   explicit AbstractRange(nsINode* aNode);
  22   virtual ~AbstractRange() = default;
  23
  24  public:
  25   AbstractRange() = delete;
  26   explicit AbstractRange(const AbstractRange& aOther) = delete;
  27
  28   /**
  29    * Called when the process is shutting down.
  30    */
  31   static void Shutdown();
  32
  33   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  34   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(AbstractRange)
  35
  36   const RangeBoundary& StartRef() const { return mStart; }
  37   const RangeBoundary& EndRef() const { return mEnd; }
  38
  39   nsIContent* GetChildAtStartOffset() const {
  40     return mStart.GetChildAtOffset();
  41   }
  42   nsIContent* GetChildAtEndOffset() const { return mEnd.GetChildAtOffset(); }
  43   bool IsPositioned() const { return mIsPositioned; }
  44   /**
  45    * https://dom.spec.whatwg.org/#concept-tree-inclusive-ancestor
  46    */
  47   nsINode* GetClosestCommonInclusiveAncestor() const;
  48
  49   // WebIDL
  50
  51   // If Range is created from JS, it's initialized with Document.createRange()
  52   // and it collaps the range to start of the Document.  Therefore, the
  53   // following WebIDL methods are called only when `mIsPositioned` is true.
  54   // So, it does not make sense to take `ErrorResult` as their parameter
  55   // since its destruction cost may appear in profile.  If you create range
  56   // object from C++ and needs to check whether it's positioned, should call
  57   // `IsPositioned()` directly.
  58
  59   nsINode* GetStartContainer() const { return mStart.Container(); }
  60   nsINode* GetEndContainer() const { return mEnd.Container(); }
  61
  62   // FYI: Returns 0 if it's not positioned.
  63   uint32_t StartOffset() const {
  64     return static_cast<uint32_t>(
  65         *mStart.Offset(RangeBoundary::OffsetFilter::kValidOrInvalidOffsets));
  66   }
  67
  68   // FYI: Returns 0 if it's not positioned.
  69   uint32_t EndOffset() const {
  70     return static_cast<uint32_t>(
  71         *mEnd.Offset(RangeBoundary::OffsetFilter::kValidOrInvalidOffsets));
  72   }
  73   bool Collapsed() const {
  74     return !mIsPositioned || (mStart.Container() == mEnd.Container() &&
  75                               StartOffset() == EndOffset());
  76   }
  77
  78   nsINode* GetParentObject() const { return mOwner; }
  79   virtual JSObject* WrapObject(JSContext* aCx,
  80                                JS::Handle<JSObject*> aGivenProto) override;
  81
  82   bool HasEqualBoundaries(const AbstractRange& aOther) const {
  83     return (mStart == aOther.mStart) && (mEnd == aOther.mEnd);
  84   }
  85
  86  protected:
  87   template <typename SPT, typename SRT, typename EPT, typename ERT,
  88             typename RangeType>
  89   static nsresult SetStartAndEndInternal(
  90       const RangeBoundaryBase<SPT, SRT>& aStartBoundary,
  91       const RangeBoundaryBase<EPT, ERT>& aEndBoundary, RangeType* aRange);
  92
  93   template <class RangeType>
  94   static bool MaybeCacheToReuse(RangeType& aInstance);
  95
  96   void Init(nsINode* aNode);
  97
  98  private:
  99   void ClearForReuse() {
 100     mOwner = nullptr;
 101     mStart = RangeBoundary();
 102     mEnd = RangeBoundary();
 103     mIsPositioned = false;
 104     mIsGenerated = false;
 105     mCalledByJS = false;
 106   }
 107
 108  protected:
 109   RefPtr<Document> mOwner;
 110   RangeBoundary mStart;
 111   RangeBoundary mEnd;
 112   // `true` if `mStart` and `mEnd` are set for StaticRange or set and valid
 113   // for nsRange.
 114   bool mIsPositioned;
 115
 116   // Used by nsRange, but this should have this for minimizing the size.
 117   bool mIsGenerated;
 118   // Used by nsRange, but this should have this for minimizing the size.
 119   bool mCalledByJS;
 120
 121   static bool sHasShutDown;
 122 };
 123
 124 }  // namespace dom
 125 }  // namespace mozilla
 126
 127 #endif  // #ifndef mozilla_dom_AbstractRange_h