1/* 2 * Copyright (C) 2009 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31#include "config.h" 32 33#include "ScriptExecutionContext.h" 34#include "SharedTimer.h" 35#include "ThreadGlobalData.h" 36#include "ThreadTimers.h" 37#include "WorkerRunLoop.h" 38#include "WorkerGlobalScope.h" 39#include "WorkerThread.h" 40#include <wtf/CurrentTime.h> 41 42namespace WebCore { 43 44class WorkerSharedTimer : public SharedTimer { 45public: 46 WorkerSharedTimer() 47 : m_sharedTimerFunction(0) 48 , m_nextFireTime(0) 49 { 50 } 51 52 // SharedTimer interface. 53 virtual void setFiredFunction(void (*function)()) { m_sharedTimerFunction = function; } 54 virtual void setFireInterval(double interval) { m_nextFireTime = interval + currentTime(); } 55 virtual void stop() { m_nextFireTime = 0; } 56 57 bool isActive() { return m_sharedTimerFunction && m_nextFireTime; } 58 double fireTime() { return m_nextFireTime; } 59 void fire() { m_sharedTimerFunction(); } 60 61private: 62 void (*m_sharedTimerFunction)(); 63 double m_nextFireTime; 64}; 65 66class ModePredicate { 67public: 68 ModePredicate(const String& mode) 69 : m_mode(mode) 70 , m_defaultMode(mode == WorkerRunLoop::defaultMode()) 71 { 72 } 73 74 bool isDefaultMode() const 75 { 76 return m_defaultMode; 77 } 78 79 bool operator()(const WorkerRunLoop::Task& task) const 80 { 81 return m_defaultMode || m_mode == task.mode(); 82 } 83 84private: 85 String m_mode; 86 bool m_defaultMode; 87}; 88 89WorkerRunLoop::WorkerRunLoop() 90 : m_sharedTimer(std::make_unique<WorkerSharedTimer>()) 91 , m_nestedCount(0) 92 , m_uniqueId(0) 93{ 94} 95 96WorkerRunLoop::~WorkerRunLoop() 97{ 98 ASSERT(!m_nestedCount); 99} 100 101String WorkerRunLoop::defaultMode() 102{ 103 return String(); 104} 105 106class RunLoopSetup { 107 WTF_MAKE_NONCOPYABLE(RunLoopSetup); 108public: 109 RunLoopSetup(WorkerRunLoop& runLoop) 110 : m_runLoop(runLoop) 111 { 112 if (!m_runLoop.m_nestedCount) 113 threadGlobalData().threadTimers().setSharedTimer(m_runLoop.m_sharedTimer.get()); 114 m_runLoop.m_nestedCount++; 115 } 116 117 ~RunLoopSetup() 118 { 119 m_runLoop.m_nestedCount--; 120 if (!m_runLoop.m_nestedCount) 121 threadGlobalData().threadTimers().setSharedTimer(0); 122 } 123private: 124 WorkerRunLoop& m_runLoop; 125}; 126 127void WorkerRunLoop::run(WorkerGlobalScope* context) 128{ 129 RunLoopSetup setup(*this); 130 ModePredicate modePredicate(defaultMode()); 131 MessageQueueWaitResult result; 132 do { 133 result = runInMode(context, modePredicate, WaitForMessage); 134 } while (result != MessageQueueTerminated); 135 runCleanupTasks(context); 136} 137 138MessageQueueWaitResult WorkerRunLoop::runInMode(WorkerGlobalScope* context, const String& mode, WaitMode waitMode) 139{ 140 RunLoopSetup setup(*this); 141 ModePredicate modePredicate(mode); 142 MessageQueueWaitResult result = runInMode(context, modePredicate, waitMode); 143 return result; 144} 145 146MessageQueueWaitResult WorkerRunLoop::runInMode(WorkerGlobalScope* context, const ModePredicate& predicate, WaitMode waitMode) 147{ 148 ASSERT(context); 149 ASSERT(context->thread().threadID() == currentThread()); 150 151 double absoluteTime = 0.0; 152 if (waitMode == WaitForMessage) 153 absoluteTime = (predicate.isDefaultMode() && m_sharedTimer->isActive()) ? m_sharedTimer->fireTime() : MessageQueue<Task>::infiniteTime(); 154 MessageQueueWaitResult result; 155 auto task = m_messageQueue.waitForMessageFilteredWithTimeout(result, predicate, absoluteTime); 156 157 // If the context is closing, don't execute any further JavaScript tasks (per section 4.1.1 of the Web Workers spec). However, there may be implementation cleanup tasks in the queue, so keep running through it. 158 159 switch (result) { 160 case MessageQueueTerminated: 161 break; 162 163 case MessageQueueMessageReceived: 164 task->performTask(*this, context); 165 break; 166 167 case MessageQueueTimeout: 168 if (!context->isClosing()) 169 m_sharedTimer->fire(); 170 break; 171 } 172 173 return result; 174} 175 176void WorkerRunLoop::runCleanupTasks(WorkerGlobalScope* context) 177{ 178 ASSERT(context); 179 ASSERT(context->thread().threadID() == currentThread()); 180 ASSERT(m_messageQueue.killed()); 181 182 while (true) { 183 auto task = m_messageQueue.tryGetMessageIgnoringKilled(); 184 if (!task) 185 return; 186 task->performTask(*this, context); 187 } 188} 189 190void WorkerRunLoop::terminate() 191{ 192 m_messageQueue.kill(); 193} 194 195void WorkerRunLoop::postTask(ScriptExecutionContext::Task task) 196{ 197 postTaskForMode(WTF::move(task), defaultMode()); 198} 199 200void WorkerRunLoop::postTaskAndTerminate(ScriptExecutionContext::Task task) 201{ 202 m_messageQueue.appendAndKill(Task::create(WTF::move(task), defaultMode().isolatedCopy())); 203} 204 205void WorkerRunLoop::postTaskForMode(ScriptExecutionContext::Task task, const String& mode) 206{ 207 m_messageQueue.append(Task::create(WTF::move(task), mode.isolatedCopy())); 208} 209 210std::unique_ptr<WorkerRunLoop::Task> WorkerRunLoop::Task::create(ScriptExecutionContext::Task task, const String& mode) 211{ 212 return std::unique_ptr<Task>(new Task(WTF::move(task), mode)); 213} 214 215void WorkerRunLoop::Task::performTask(const WorkerRunLoop& runLoop, WorkerGlobalScope* context) 216{ 217 if ((!context->isClosing() && !runLoop.terminated()) || m_task.isCleanupTask()) 218 m_task.performTask(*context); 219} 220 221WorkerRunLoop::Task::Task(ScriptExecutionContext::Task task, const String& mode) 222 : m_task(WTF::move(task)) 223 , m_mode(mode.isolatedCopy()) 224{ 225} 226 227} // namespace WebCore 228