| /* |
| * Copyright (C) 2011 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. |
| * * Redistributions in binary form must reproduce the above |
| * copyright notice, this list of conditions and the following disclaimer |
| * in the documentation and/or other materials provided with the |
| * distribution. |
| * * 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 THIRD_PARTY_BLINK_RENDERER_CORE_DOM_CHILD_LIST_MUTATION_SCOPE_H_ |
| #define THIRD_PARTY_BLINK_RENDERER_CORE_DOM_CHILD_LIST_MUTATION_SCOPE_H_ |
| |
| #include "base/macros.h" |
| #include "third_party/blink/renderer/core/dom/document.h" |
| #include "third_party/blink/renderer/core/dom/mutation_observer.h" |
| #include "third_party/blink/renderer/core/dom/node.h" |
| #include "third_party/blink/renderer/platform/heap/handle.h" |
| |
| namespace blink { |
| |
| class MutationObserverInterestGroup; |
| |
| // ChildListMutationAccumulator is not meant to be used directly; |
| // ChildListMutationScope is the public interface. |
| // |
| // One ChildListMutationAccumulator for a given Node is shared between all the |
| // active ChildListMutationScopes for that Node. Once the last |
| // ChildListMutationScope is destructed the accumulator enqueues a mutation |
| // record for the recorded mutations and the accumulator can be garbage |
| // collected. |
| class ChildListMutationAccumulator final |
| : public GarbageCollected<ChildListMutationAccumulator> { |
| public: |
| static ChildListMutationAccumulator* GetOrCreate(Node&); |
| |
| ChildListMutationAccumulator(Node*, MutationObserverInterestGroup*); |
| |
| void ChildAdded(Node&); |
| void WillRemoveChild(Node&); |
| |
| bool HasObservers() const { return observers_; } |
| |
| // Register and unregister mutation scopes that are using this mutation |
| // accumulator. |
| void EnterMutationScope() { mutation_scopes_++; } |
| void LeaveMutationScope(); |
| |
| void Trace(Visitor*); |
| |
| private: |
| void EnqueueMutationRecord(); |
| bool IsEmpty(); |
| bool IsAddedNodeInOrder(Node&); |
| bool IsRemovedNodeInOrder(Node&); |
| |
| Member<Node> target_; |
| |
| HeapVector<Member<Node>> removed_nodes_; |
| HeapVector<Member<Node>> added_nodes_; |
| Member<Node> previous_sibling_; |
| Member<Node> next_sibling_; |
| Member<Node> last_added_; |
| |
| Member<MutationObserverInterestGroup> observers_; |
| |
| unsigned mutation_scopes_; |
| }; |
| |
| class ChildListMutationScope final { |
| STACK_ALLOCATED(); |
| |
| public: |
| explicit ChildListMutationScope(Node& target) { |
| if (target.GetDocument().HasMutationObserversOfType( |
| kMutationTypeChildList)) { |
| accumulator_ = ChildListMutationAccumulator::GetOrCreate(target); |
| // Register another user of the accumulator. |
| accumulator_->EnterMutationScope(); |
| } |
| } |
| |
| ~ChildListMutationScope() { |
| if (accumulator_) { |
| // Unregister a user of the accumulator. If this is the last user |
| // the accumulator will enqueue a mutation record for the mutations. |
| accumulator_->LeaveMutationScope(); |
| } |
| } |
| |
| void ChildAdded(Node& child) { |
| if (accumulator_ && accumulator_->HasObservers()) |
| accumulator_->ChildAdded(child); |
| } |
| |
| void WillRemoveChild(Node& child) { |
| if (accumulator_ && accumulator_->HasObservers()) |
| accumulator_->WillRemoveChild(child); |
| } |
| |
| private: |
| Member<ChildListMutationAccumulator> accumulator_; |
| DISALLOW_COPY_AND_ASSIGN(ChildListMutationScope); |
| }; |
| |
| } // namespace blink |
| |
| #endif // THIRD_PARTY_BLINK_RENDERER_CORE_DOM_CHILD_LIST_MUTATION_SCOPE_H_ |