third_party/WebKit/Source/core/dom/NodeTraversal.cpp

   1 /*
   2  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
   3  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
   4  *           (C) 2001 Dirk Mueller (mueller@kde.org)
   5  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
   6  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Library General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Library General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Library General Public License
  19  * along with this library; see the file COPYING.LIB.  If not, write to
  20  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  21  * Boston, MA 02110-1301, USA.
  22  *
  23  */
  24
  25 #include "config.h"
  26 #include "core/dom/NodeTraversal.h"
  27
  28 #include "core/dom/ContainerNode.h"
  29 #include "core/dom/Range.h"
  30
  31 namespace blink {
  32
  33 Node* NodeTraversal::previousIncludingPseudo(const Node& current, const Node* stayWithin)
  34 {
  35     if (current == stayWithin)
  36         return 0;
  37     if (Node* previous = current.pseudoAwarePreviousSibling()) {
  38         while (previous->pseudoAwareLastChild())
  39             previous = previous->pseudoAwareLastChild();
  40         return previous;
  41     }
  42     return current.parentNode();
  43 }
  44
  45 Node* NodeTraversal::nextIncludingPseudo(const Node& current, const Node* stayWithin)
  46 {
  47     if (Node* next = current.pseudoAwareFirstChild())
  48         return next;
  49     if (current == stayWithin)
  50         return 0;
  51     if (Node* next = current.pseudoAwareNextSibling())
  52         return next;
  53     for (Node* parent = current.parentNode(); parent; parent = parent->parentNode()) {
  54         if (parent == stayWithin)
  55             return 0;
  56         if (Node* next = parent->pseudoAwareNextSibling())
  57             return next;
  58     }
  59     return 0;
  60 }
  61
  62 Node* NodeTraversal::nextIncludingPseudoSkippingChildren(const Node& current, const Node* stayWithin)
  63 {
  64     if (current == stayWithin)
  65         return 0;
  66     if (Node* next = current.pseudoAwareNextSibling())
  67         return next;
  68     for (Node* parent = current.parentNode(); parent; parent = parent->parentNode()) {
  69         if (parent == stayWithin)
  70             return 0;
  71         if (Node* next = parent->pseudoAwareNextSibling())
  72             return next;
  73     }
  74     return 0;
  75 }
  76
  77 Node* NodeTraversal::nextAncestorSibling(const Node& current)
  78 {
  79     ASSERT(!current.nextSibling());
  80     for (Node* parent = current.parentNode(); parent; parent = parent->parentNode()) {
  81         if (parent->nextSibling())
  82             return parent->nextSibling();
  83     }
  84     return 0;
  85 }
  86
  87 Node* NodeTraversal::nextAncestorSibling(const Node& current, const Node* stayWithin)
  88 {
  89     ASSERT(!current.nextSibling());
  90     ASSERT(current != stayWithin);
  91     for (Node* parent = current.parentNode(); parent; parent = parent->parentNode()) {
  92         if (parent == stayWithin)
  93             return 0;
  94         if (parent->nextSibling())
  95             return parent->nextSibling();
  96     }
  97     return 0;
  98 }
  99
 100 Node* NodeTraversal::lastWithin(const ContainerNode& current)
 101 {
 102     Node* descendant = current.lastChild();
 103     for (Node* child = descendant; child; child = child->lastChild())
 104         descendant = child;
 105     return descendant;
 106 }
 107
 108 Node& NodeTraversal::lastWithinOrSelf(Node& current)
 109 {
 110     Node* lastDescendant = current.isContainerNode() ? NodeTraversal::lastWithin(toContainerNode(current)) : 0;
 111     return lastDescendant ? *lastDescendant : current;
 112 }
 113
 114 Node* NodeTraversal::previous(const Node& current, const Node* stayWithin)
 115 {
 116     if (current == stayWithin)
 117         return 0;
 118     if (current.previousSibling()) {
 119         Node* previous = current.previousSibling();
 120         while (Node* child = previous->lastChild())
 121             previous = child;
 122         return previous;
 123     }
 124     return current.parentNode();
 125 }
 126
 127 Node* NodeTraversal::previousSkippingChildren(const Node& current, const Node* stayWithin)
 128 {
 129     if (current == stayWithin)
 130         return 0;
 131     if (current.previousSibling())
 132         return current.previousSibling();
 133     for (Node* parent = current.parentNode(); parent; parent = parent->parentNode()) {
 134         if (parent == stayWithin)
 135             return 0;
 136         if (parent->previousSibling())
 137             return parent->previousSibling();
 138     }
 139     return 0;
 140 }
 141
 142 Node* NodeTraversal::nextPostOrder(const Node& current, const Node* stayWithin)
 143 {
 144     if (current == stayWithin)
 145         return 0;
 146     if (!current.nextSibling())
 147         return current.parentNode();
 148     Node* next = current.nextSibling();
 149     while (Node* child = next->firstChild())
 150         next = child;
 151     return next;
 152 }
 153
 154 static Node* previousAncestorSiblingPostOrder(const Node& current, const Node* stayWithin)
 155 {
 156     ASSERT(!current.previousSibling());
 157     for (Node* parent = current.parentNode(); parent; parent = parent->parentNode()) {
 158         if (parent == stayWithin)
 159             return 0;
 160         if (parent->previousSibling())
 161             return parent->previousSibling();
 162     }
 163     return 0;
 164 }
 165
 166 Node* NodeTraversal::previousPostOrder(const Node& current, const Node* stayWithin)
 167 {
 168     if (Node* lastChild = current.lastChild())
 169         return lastChild;
 170     if (current == stayWithin)
 171         return 0;
 172     if (current.previousSibling())
 173         return current.previousSibling();
 174     return previousAncestorSiblingPostOrder(current, stayWithin);
 175 }
 176
 177 Node* NodeTraversal::commonAncestor(const Node& nodeA, const Node& nodeB)
 178 {
 179     return Range::commonAncestorContainer(&nodeA, &nodeB);
 180 }
 181
 182 } // namespace blink