layout/base/nsGenConList.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /* base class for nsCounterList and nsQuoteList */
   7
   8 #ifndef nsGenConList_h___
   9 #define nsGenConList_h___
  10
  11 #include "nsIFrame.h"
  12 #include "nsStyleStruct.h"
  13 #include "prclist.h"
  14 #include "nsCSSPseudoElements.h"
  15 #include "nsTextNode.h"
  16
  17 class nsGenConList;
  18
  19 struct nsGenConNode : public PRCList {
  20   // The wrapper frame for all of the pseudo-element's content.  This
  21   // frame generally has useful style data and has the
  22   // NS_FRAME_GENERATED_CONTENT bit set (so we use it to track removal),
  23   // but does not necessarily for |nsCounterChangeNode|s.
  24   nsIFrame* mPseudoFrame;
  25
  26   // Index within the list of things specified by the 'content' property,
  27   // which is needed to do 'content: open-quote open-quote' correctly,
  28   // and needed for similar cases for counters.
  29   const int32_t mContentIndex;
  30
  31   // null for 'content:no-open-quote', 'content:no-close-quote' and for
  32   // counter nodes for increments and resets (rather than uses)
  33   nsRefPtr<nsTextNode> mText;
  34
  35   explicit nsGenConNode(int32_t aContentIndex)
  36     : mPseudoFrame(nullptr)
  37     , mContentIndex(aContentIndex)
  38   {
  39   }
  40
  41   /**
  42    * Finish initializing the generated content node once we know the
  43    * relevant text frame. This must be called just after
  44    * the textframe has been initialized. This need not be called at all
  45    * for nodes that don't generate text. This will generally set the
  46    * mPseudoFrame, insert the node into aList, and set aTextFrame up
  47    * with the correct text.
  48    * @param aList the list the node belongs to
  49    * @param aPseudoFrame the :before or :after frame
  50    * @param aTextFrame the textframe where the node contents will render
  51    * @return true iff this marked the list dirty
  52    */
  53   virtual bool InitTextFrame(nsGenConList* aList, nsIFrame* aPseudoFrame,
  54                                nsIFrame* aTextFrame)
  55   {
  56     mPseudoFrame = aPseudoFrame;
  57     CheckFrameAssertions();
  58     return false;
  59   }
  60
  61   virtual ~nsGenConNode() {} // XXX Avoid, perhaps?
  62
  63 protected:
  64   void CheckFrameAssertions() {
  65     NS_ASSERTION(mContentIndex <
  66                    int32_t(mPseudoFrame->StyleContent()->ContentCount()),
  67                  "index out of range");
  68       // We allow negative values of mContentIndex for 'counter-reset' and
  69       // 'counter-increment'.
  70
  71     NS_ASSERTION(mContentIndex < 0 ||
  72                  mPseudoFrame->StyleContext()->GetPseudo() ==
  73                    nsCSSPseudoElements::before ||
  74                  mPseudoFrame->StyleContext()->GetPseudo() ==
  75                    nsCSSPseudoElements::after,
  76                  "not :before/:after generated content and not counter change");
  77     NS_ASSERTION(mContentIndex < 0 ||
  78                  mPseudoFrame->GetStateBits() & NS_FRAME_GENERATED_CONTENT,
  79                  "not generated content and not counter change");
  80   }
  81 };
  82
  83 class nsGenConList {
  84 protected:
  85   nsGenConNode* mFirstNode;
  86   uint32_t mSize;
  87 public:
  88   nsGenConList() : mFirstNode(nullptr), mSize(0) {}
  89   ~nsGenConList() { Clear(); }
  90   void Clear();
  91   static nsGenConNode* Next(nsGenConNode* aNode) {
  92     return static_cast<nsGenConNode*>(PR_NEXT_LINK(aNode));
  93   }
  94   static nsGenConNode* Prev(nsGenConNode* aNode) {
  95     return static_cast<nsGenConNode*>(PR_PREV_LINK(aNode));
  96   }
  97   void Insert(nsGenConNode* aNode);
  98   // returns whether any nodes have been destroyed
  99   bool DestroyNodesFor(nsIFrame* aFrame); //destroy all nodes with aFrame as parent
 100
 101   // Return true if |aNode1| is after |aNode2|.
 102   static bool NodeAfter(const nsGenConNode* aNode1,
 103                           const nsGenConNode* aNode2);
 104
 105   void Remove(nsGenConNode* aNode) { PR_REMOVE_LINK(aNode); mSize--; }
 106   bool IsLast(nsGenConNode* aNode) { return (Next(aNode) == mFirstNode); }
 107 };
 108
 109 #endif /* nsGenConList_h___ */