| /* |
| * Copyright (C) 2013 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 PartialLayoutState_h |
| #define PartialLayoutState_h |
| |
| #include "core/rendering/RenderObject.h" |
| |
| namespace WebCore { |
| |
| class PartialLayoutState { |
| friend class PartialLayoutDisabler; |
| public: |
| PartialLayoutState() |
| : m_shouldStop(false) |
| , m_stopAtRenderer(0) |
| , m_disableCount(0) |
| { |
| } |
| |
| // True if we plan to do a partial layout, or are in the process of stopping a partial layout. |
| bool isPartialLayout() const { return m_stopAtRenderer || m_shouldStop; } |
| |
| bool isStopping() const { return m_shouldStop; } |
| bool checkPartialLayoutComplete(const RenderObject*); |
| void setStopAtRenderer(const RenderObject* renderer) { m_stopAtRenderer = renderer; } |
| void reset() { m_shouldStop = false; m_stopAtRenderer = 0; } |
| |
| private: |
| void disable() { ASSERT(!m_shouldStop); m_disableCount++; } |
| void enable() { ASSERT(m_disableCount > 0); m_disableCount--; } |
| const RenderObject* stopAtRenderer() const { return m_disableCount > 0 ? 0 : m_stopAtRenderer; } |
| |
| bool m_shouldStop; |
| const RenderObject* m_stopAtRenderer; |
| int m_disableCount; |
| }; |
| |
| inline bool PartialLayoutState::checkPartialLayoutComplete(const RenderObject* renderer) |
| { |
| if (m_shouldStop) |
| return true; |
| |
| if (renderer == stopAtRenderer()) { |
| m_shouldStop = true; |
| m_stopAtRenderer = 0; |
| return true; |
| } |
| |
| return false; |
| } |
| |
| class PartialLayoutDisabler { |
| WTF_MAKE_NONCOPYABLE(PartialLayoutDisabler); |
| public: |
| PartialLayoutDisabler(PartialLayoutState& partialLayout, bool disable = true) |
| : m_partialLayout(partialLayout) |
| , m_disable(disable) |
| { |
| if (m_disable) |
| m_partialLayout.disable(); |
| } |
| |
| ~PartialLayoutDisabler() |
| { |
| if (m_disable) |
| m_partialLayout.enable(); |
| } |
| private: |
| PartialLayoutState& m_partialLayout; |
| bool m_disable; |
| }; |
| |
| } // namespace WebCore |
| |
| #endif // PartialLayoutState_h |