1 /* 2 * Copyright (C) 2007, 2008 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef PositionIterator_h 27 #define PositionIterator_h 28 29 #include "core/dom/Node.h" 30 #include "core/dom/Position.h" 31 32 namespace WebCore { 33 34 // A Position iterator with constant-time 35 // increment, decrement, and several predicates on the Position it is at. 36 // Conversion to/from Position is O(n) in the offset. 37 class PositionIterator { 38 STACK_ALLOCATED(); 39 public: 40 PositionIterator() 41 : m_anchorNode(nullptr) 42 , m_nodeAfterPositionInAnchor(nullptr) 43 , m_offsetInAnchor(0) 44 { 45 } 46 47 PositionIterator(const Position& pos) 48 : m_anchorNode(pos.anchorNode()) 49 , m_nodeAfterPositionInAnchor(m_anchorNode->traverseToChildAt(pos.deprecatedEditingOffset())) 50 , m_offsetInAnchor(m_nodeAfterPositionInAnchor ? 0 : pos.deprecatedEditingOffset()) 51 { 52 } 53 operator Position() const; 54 55 void increment(); 56 void decrement(); 57 58 Node* node() const { return m_anchorNode; } 59 int offsetInLeafNode() const { return m_offsetInAnchor; } 60 61 bool atStart() const; 62 bool atEnd() const; 63 bool atStartOfNode() const; 64 bool atEndOfNode() const; 65 bool isCandidate() const; 66 67 private: 68 RawPtrWillBeMember<Node> m_anchorNode; 69 RawPtrWillBeMember<Node> m_nodeAfterPositionInAnchor; // If this is non-null, m_nodeAfterPositionInAnchor->parentNode() == m_anchorNode; 70 int m_offsetInAnchor; 71 }; 72 73 } // namespace WebCore 74 75 #endif // PositionIterator_h 76