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/*
* Copyright (C) 2010 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:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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 HTMLParserScheduler_h
#define HTMLParserScheduler_h
#include "NestingLevelIncrementer.h"
#include "Timer.h"
#include <wtf/CurrentTime.h>
#include <wtf/RefPtr.h>
#if PLATFORM(IOS)
#include "WebCoreThread.h"
#endif
namespace WebCore {
class Document;
class HTMLDocumentParser;
class ActiveParserSession {
public:
explicit ActiveParserSession(Document*);
~ActiveParserSession();
private:
RefPtr<Document> m_document;
};
class PumpSession : public NestingLevelIncrementer, public ActiveParserSession {
public:
PumpSession(unsigned& nestingLevel, Document*);
~PumpSession();
int processedTokens;
double startTime;
bool needsYield;
bool didSeeScript;
};
class HTMLParserScheduler {
WTF_MAKE_NONCOPYABLE(HTMLParserScheduler); WTF_MAKE_FAST_ALLOCATED;
public:
explicit HTMLParserScheduler(HTMLDocumentParser&);
~HTMLParserScheduler();
// Inline as this is called after every token in the parser.
void checkForYieldBeforeToken(PumpSession& session)
{
#if PLATFORM(IOS)
if (WebThreadShouldYield())
session.needsYield = true;
#endif
if (session.processedTokens > m_parserChunkSize || session.didSeeScript) {
// monotonicallyIncreasingTime() can be expensive. By delaying, we avoided calling
// monotonicallyIncreasingTime() when constructing non-yielding PumpSessions.
if (!session.startTime)
session.startTime = monotonicallyIncreasingTime();
session.processedTokens = 0;
session.didSeeScript = false;
double elapsedTime = monotonicallyIncreasingTime() - session.startTime;
if (elapsedTime > m_parserTimeLimit)
session.needsYield = true;
}
++session.processedTokens;
}
void checkForYieldBeforeScript(PumpSession&);
void scheduleForResume();
bool isScheduledForResume() const { return m_isSuspendedWithActiveTimer || m_continueNextChunkTimer.isActive(); }
void suspend();
void resume();
private:
void continueNextChunkTimerFired();
HTMLDocumentParser& m_parser;
double m_parserTimeLimit;
int m_parserChunkSize;
Timer m_continueNextChunkTimer;
bool m_isSuspendedWithActiveTimer;
#if !ASSERT_DISABLED
bool m_suspended;
#endif
};
}
#endif
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