Home | History | Annotate | Download | only in js 
      1 /*
      2  * Copyright (C) 2008 Apple 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
      6  * are met:
      7  * 1. Redistributions of source code must retain the above copyright
      8  *    notice, this list of conditions and the following disclaimer.
      9  * 2. Redistributions in binary form must reproduce the above copyright
     10  *    notice, this list of conditions and the following disclaimer in the
     11  *    documentation and/or other materials provided with the distribution.
     12  *
     13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
     14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
     17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
     21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     24  *
     25  */
     26 
     27 #include "config.h"
     28 
     29 #if ENABLE(WORKERS)
     30 
     31 #include "WorkerScriptController.h"
     32 
     33 #include "JSDOMBinding.h"
     34 #include "JSDedicatedWorkerContext.h"
     35 #include "JSSharedWorkerContext.h"
     36 #include "ScriptSourceCode.h"
     37 #include "ScriptValue.h"
     38 #include "WorkerContext.h"
     39 #include "WorkerObjectProxy.h"
     40 #include "WorkerThread.h"
     41 #include <interpreter/Interpreter.h>
     42 #include <runtime/Completion.h>
     43 #include <runtime/Completion.h>
     44 #include <runtime/JSLock.h>
     45 
     46 using namespace JSC;
     47 
     48 namespace WebCore {
     49 
     50 WorkerScriptController::WorkerScriptController(WorkerContext* workerContext)
     51     : m_globalData(JSGlobalData::create())
     52     , m_workerContext(workerContext)
     53     , m_executionForbidden(false)
     54 {
     55     m_globalData->clientData = new WebCoreJSClientData(m_globalData.get());
     56 }
     57 
     58 WorkerScriptController::~WorkerScriptController()
     59 {
     60     m_workerContextWrapper = 0; // Unprotect the global object.
     61     m_globalData->heap.destroy();
     62 }
     63 
     64 void WorkerScriptController::initScript()
     65 {
     66     ASSERT(!m_workerContextWrapper);
     67 
     68     JSLock lock(SilenceAssertionsOnly);
     69 
     70     // Explicitly protect the global object's prototype so it isn't collected
     71     // when we allocate the global object. (Once the global object is fully
     72     // constructed, it can mark its own prototype.)
     73     RefPtr<Structure> workerContextPrototypeStructure = JSWorkerContextPrototype::createStructure(jsNull());
     74     ProtectedPtr<JSWorkerContextPrototype> workerContextPrototype = new (m_globalData.get()) JSWorkerContextPrototype(workerContextPrototypeStructure.release());
     75 
     76     if (m_workerContext->isDedicatedWorkerContext()) {
     77         RefPtr<Structure> dedicatedContextPrototypeStructure = JSDedicatedWorkerContextPrototype::createStructure(workerContextPrototype);
     78         ProtectedPtr<JSDedicatedWorkerContextPrototype> dedicatedContextPrototype = new (m_globalData.get()) JSDedicatedWorkerContextPrototype(dedicatedContextPrototypeStructure.release());
     79         RefPtr<Structure> structure = JSDedicatedWorkerContext::createStructure(dedicatedContextPrototype);
     80 
     81         m_workerContextWrapper = new (m_globalData.get()) JSDedicatedWorkerContext(structure.release(), m_workerContext->toDedicatedWorkerContext());
     82 #if ENABLE(SHARED_WORKERS)
     83     } else {
     84         ASSERT(m_workerContext->isSharedWorkerContext());
     85         RefPtr<Structure> sharedContextPrototypeStructure = JSSharedWorkerContextPrototype::createStructure(workerContextPrototype);
     86         ProtectedPtr<JSSharedWorkerContextPrototype> sharedContextPrototype = new (m_globalData.get()) JSSharedWorkerContextPrototype(sharedContextPrototypeStructure.release());
     87         RefPtr<Structure> structure = JSSharedWorkerContext::createStructure(sharedContextPrototype);
     88 
     89         m_workerContextWrapper = new (m_globalData.get()) JSSharedWorkerContext(structure.release(), m_workerContext->toSharedWorkerContext());
     90 #endif
     91     }
     92 }
     93 
     94 ScriptValue WorkerScriptController::evaluate(const ScriptSourceCode& sourceCode)
     95 {
     96     {
     97         MutexLocker lock(m_sharedDataMutex);
     98         if (m_executionForbidden)
     99             return JSValue();
    100     }
    101     ScriptValue exception;
    102     ScriptValue result = evaluate(sourceCode, &exception);
    103     if (exception.jsValue()) {
    104         JSLock lock(SilenceAssertionsOnly);
    105         reportException(m_workerContextWrapper->globalExec(), exception.jsValue());
    106     }
    107     return result;
    108 }
    109 
    110 ScriptValue WorkerScriptController::evaluate(const ScriptSourceCode& sourceCode, ScriptValue* exception)
    111 {
    112     {
    113         MutexLocker lock(m_sharedDataMutex);
    114         if (m_executionForbidden)
    115             return JSValue();
    116     }
    117 
    118     initScriptIfNeeded();
    119     JSLock lock(SilenceAssertionsOnly);
    120 
    121     ExecState* exec = m_workerContextWrapper->globalExec();
    122     m_workerContextWrapper->globalData()->timeoutChecker.start();
    123     Completion comp = JSC::evaluate(exec, exec->dynamicGlobalObject()->globalScopeChain(), sourceCode.jsSourceCode(), m_workerContextWrapper);
    124     m_workerContextWrapper->globalData()->timeoutChecker.stop();
    125 
    126     if (comp.complType() == Normal || comp.complType() == ReturnValue)
    127         return comp.value();
    128 
    129     if (comp.complType() == Throw)
    130         *exception = comp.value();
    131     return JSValue();
    132 }
    133 
    134 void WorkerScriptController::setException(ScriptValue exception)
    135 {
    136     m_workerContextWrapper->globalExec()->setException(exception.jsValue());
    137 }
    138 
    139 void WorkerScriptController::forbidExecution()
    140 {
    141     // This function is called from another thread.
    142     // Mutex protection for m_executionForbidden is needed to guarantee that the value is synchronized between processors, because
    143     // if it were not, the worker could re-enter JSC::evaluate(), but with timeout already reset.
    144     // It is not critical for Interpreter::m_timeoutTime to be synchronized, we just rely on it reaching the worker thread's processor sooner or later.
    145     MutexLocker lock(m_sharedDataMutex);
    146     m_executionForbidden = true;
    147     m_globalData->timeoutChecker.setTimeoutInterval(1); // 1ms is the smallest timeout that can be set.
    148 }
    149 
    150 } // namespace WebCore
    151 
    152 #endif // ENABLE(WORKERS)
    153