| /* |
| * Copyright (C) 2012 Google Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are |
| * met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Neither the name of Google Inc. nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #ifndef FlatTreeTraversal_h |
| #define FlatTreeTraversal_h |
| |
| #include "core/CoreExport.h" |
| #include "core/dom/Document.h" |
| #include "core/dom/LayoutTreeBuilderTraversal.h" |
| #include "core/dom/shadow/InsertionPoint.h" |
| #include "core/dom/shadow/ShadowRoot.h" |
| #include "wtf/Allocator.h" |
| |
| namespace blink { |
| |
| class ContainerNode; |
| class HTMLSlotElement; |
| class Node; |
| |
| // Flat tree version of |NodeTraversal|. |
| // |
| // None of member functions takes a |ShadowRoot| or an active insertion point, |
| // e.g. roughly speaking <content> and <shadow> in the shadow tree, see |
| // |InsertionPoint::isActive()| for details of active insertion points, since |
| // they aren't appeared in the flat tree. |assertPrecondition()| and |
| // |assertPostCondition()| check this condition. |
| // |
| // FIXME: Make some functions inline to optimise the performance. |
| // https://bugs.webkit.org/show_bug.cgi?id=82702 |
| class CORE_EXPORT FlatTreeTraversal { |
| STATIC_ONLY(FlatTreeTraversal); |
| public: |
| typedef LayoutTreeBuilderTraversal::ParentDetails ParentTraversalDetails; |
| |
| static Node* next(const Node&); |
| static Node* next(const Node&, const Node* stayWithin); |
| static Node* previous(const Node&); |
| |
| static Node* firstChild(const Node&); |
| static Node* lastChild(const Node&); |
| static bool hasChildren(const Node&); |
| |
| static ContainerNode* parent(const Node&, ParentTraversalDetails* = 0); |
| static Element* parentElement(const Node&); |
| |
| static Node* nextSibling(const Node&); |
| static Node* previousSibling(const Node&); |
| |
| // Returns a child node at |index|. If |index| is greater than or equal to |
| // the children, this function returns |nullptr|. |
| static Node* childAt(const Node&, unsigned index); |
| |
| // Flat tree version of |NodeTraversal::nextSkippingChildren()|. This |
| // function is similar to |next()| but skips child nodes of a specified |
| // node. |
| static Node* nextSkippingChildren(const Node&); |
| static Node* nextSkippingChildren(const Node&, const Node* stayWithin); |
| |
| // Flat tree version of |NodeTraversal::previousSkippingChildren()| |
| // similar to |previous()| but skipping child nodes of the specified node. |
| static Node* previousSkippingChildren(const Node&); |
| |
| // Like previous, but visits parents before their children. |
| static Node* previousPostOrder(const Node&, const Node* stayWithin = nullptr); |
| |
| // Flat tree version of |Node::isDescendantOf(other)|. This function |
| // returns true if |other| contains |node|, otherwise returns |
| // false. If |other| is |node|, this function returns false. |
| static bool isDescendantOf(const Node& /*node*/, const Node& other); |
| |
| static bool contains(const ContainerNode& container, const Node& node) |
| { |
| assertPrecondition(container); |
| assertPrecondition(node); |
| return container == node || isDescendantOf(node, container); |
| } |
| |
| static bool containsIncludingPseudoElement(const ContainerNode&, const Node&); |
| |
| // Returns a common ancestor of |nodeA| and |nodeB| if exists, otherwise |
| // returns |nullptr|. |
| static Node* commonAncestor(const Node& nodeA, const Node& nodeB); |
| |
| // Flat tree version of |Node::nodeIndex()|. This function returns a |
| // zero base position number of the specified node in child nodes list, or |
| // zero if the specified node has no parent. |
| static unsigned index(const Node&); |
| |
| // Flat tree version of |ContainerNode::countChildren()|. This function |
| // returns the number of the child nodes of the specified node in the |
| // flat tree. |
| static unsigned countChildren(const Node&); |
| |
| static Node* lastWithin(const Node&); |
| static Node& lastWithinOrSelf(const Node&); |
| |
| private: |
| enum TraversalDirection { |
| TraversalDirectionForward, |
| TraversalDirectionBackward |
| }; |
| |
| static void assertPrecondition(const Node& node) |
| { |
| #if ENABLE(ASSERT) |
| ASSERT(!node.needsDistributionRecalc()); |
| ASSERT(node.canParticipateInFlatTree()); |
| #endif |
| } |
| |
| static void assertPostcondition(const Node* node) |
| { |
| #if ENABLE(ASSERT) |
| if (node) |
| assertPrecondition(*node); |
| #endif |
| } |
| |
| static Node* resolveDistributionStartingAt(const Node*, TraversalDirection); |
| static Node* v0ResolveDistributionStartingAt(const Node&, TraversalDirection); |
| |
| static Node* traverseNext(const Node&); |
| static Node* traverseNext(const Node&, const Node* stayWithin); |
| static Node* traverseNextSkippingChildren(const Node&, const Node* stayWithin); |
| static Node* traversePrevious(const Node&); |
| |
| static Node* traverseFirstChild(const Node&); |
| static Node* traverseLastChild(const Node&); |
| static Node* traverseChild(const Node&, TraversalDirection); |
| |
| static ContainerNode* traverseParent(const Node&, ParentTraversalDetails* = 0); |
| // TODO(hayato): Make ParentTraversalDetails be aware of slot elements too. |
| static ContainerNode* traverseParentForV0(const Node&, ParentTraversalDetails* = 0); |
| static ContainerNode* traverseParentOrHost(const Node&); |
| |
| static Node* traverseNextSibling(const Node&); |
| static Node* traversePreviousSibling(const Node&); |
| |
| static Node* traverseSiblings(const Node&, TraversalDirection); |
| static Node* traverseSiblingsForV1HostChild(const Node&, TraversalDirection); |
| static Node* traverseSiblingsForV0Distribution(const Node&, TraversalDirection); |
| |
| static Node* traverseNextAncestorSibling(const Node&); |
| static Node* traversePreviousAncestorSibling(const Node&); |
| }; |
| |
| inline ContainerNode* FlatTreeTraversal::parent(const Node& node, ParentTraversalDetails* details) |
| { |
| assertPrecondition(node); |
| ContainerNode* result = traverseParent(node, details); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline Element* FlatTreeTraversal::parentElement(const Node& node) |
| { |
| ContainerNode* parent = FlatTreeTraversal::parent(node); |
| return parent && parent->isElementNode() ? toElement(parent) : nullptr; |
| } |
| |
| inline Node* FlatTreeTraversal::nextSibling(const Node& node) |
| { |
| assertPrecondition(node); |
| Node* result = traverseSiblings(node, TraversalDirectionForward); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline Node* FlatTreeTraversal::previousSibling(const Node& node) |
| { |
| assertPrecondition(node); |
| Node* result = traverseSiblings(node, TraversalDirectionBackward); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline Node* FlatTreeTraversal::next(const Node& node) |
| { |
| assertPrecondition(node); |
| Node* result = traverseNext(node); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline Node* FlatTreeTraversal::next(const Node& node, const Node* stayWithin) |
| { |
| assertPrecondition(node); |
| Node* result = traverseNext(node, stayWithin); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline Node* FlatTreeTraversal::nextSkippingChildren(const Node& node, const Node* stayWithin) |
| { |
| assertPrecondition(node); |
| Node* result = traverseNextSkippingChildren(node, stayWithin); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline Node* FlatTreeTraversal::traverseNext(const Node& node) |
| { |
| if (Node* next = traverseFirstChild(node)) |
| return next; |
| for (const Node* next = &node; next; next = traverseParent(*next)) { |
| if (Node* sibling = traverseNextSibling(*next)) |
| return sibling; |
| } |
| return nullptr; |
| } |
| |
| inline Node* FlatTreeTraversal::traverseNext(const Node& node, const Node* stayWithin) |
| { |
| if (Node* next = traverseFirstChild(node)) |
| return next; |
| return traverseNextSkippingChildren(node, stayWithin); |
| } |
| |
| inline Node* FlatTreeTraversal::traverseNextSkippingChildren(const Node& node, const Node* stayWithin) |
| { |
| for (const Node* next = &node; next; next = traverseParent(*next)) { |
| if (next == stayWithin) |
| return nullptr; |
| if (Node* sibling = traverseNextSibling(*next)) |
| return sibling; |
| } |
| return nullptr; |
| } |
| |
| inline Node* FlatTreeTraversal::previous(const Node& node) |
| { |
| assertPrecondition(node); |
| Node* result = traversePrevious(node); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline Node* FlatTreeTraversal::traversePrevious(const Node& node) |
| { |
| if (Node* previous = traversePreviousSibling(node)) { |
| while (Node* child = traverseLastChild(*previous)) |
| previous = child; |
| return previous; |
| } |
| return traverseParent(node); |
| } |
| |
| inline Node* FlatTreeTraversal::firstChild(const Node& node) |
| { |
| assertPrecondition(node); |
| Node* result = traverseChild(node, TraversalDirectionForward); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline Node* FlatTreeTraversal::lastChild(const Node& node) |
| { |
| assertPrecondition(node); |
| Node* result = traverseLastChild(node); |
| assertPostcondition(result); |
| return result; |
| } |
| |
| inline bool FlatTreeTraversal::hasChildren(const Node& node) |
| { |
| return firstChild(node); |
| } |
| |
| inline Node* FlatTreeTraversal::traverseNextSibling(const Node& node) |
| { |
| return traverseSiblings(node, TraversalDirectionForward); |
| } |
| |
| inline Node* FlatTreeTraversal::traversePreviousSibling(const Node& node) |
| { |
| return traverseSiblings(node, TraversalDirectionBackward); |
| } |
| |
| inline Node* FlatTreeTraversal::traverseFirstChild(const Node& node) |
| { |
| return traverseChild(node, TraversalDirectionForward); |
| } |
| |
| inline Node* FlatTreeTraversal::traverseLastChild(const Node& node) |
| { |
| return traverseChild(node, TraversalDirectionBackward); |
| } |
| |
| } // namespace blink |
| |
| #endif |