jsglobalobject.cpp

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

/*
 * Copyright (C) 2007, 2008, 2009 Apple Inc. All rights reserved.
 * Copyright (C) 2008 Cameron Zwarich ([e-mail])
 *
 * 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. 
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") 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 APPLE AND ITS 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 APPLE OR ITS 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.
 */

#include "config.h"
#include "JSGlobalObject.h"

#include "JSCallbackConstructor.h"
#include "JSCallbackFunction.h"
#include "JSCallbackObject.h"

#include "Arguments.h"
#include "ArrayConstructor.h"
#include "ArrayPrototype.h"
#include "BooleanConstructor.h"
#include "BooleanPrototype.h"
#include "CodeBlock.h"
#include "DateConstructor.h"
#include "DatePrototype.h"
#include "ErrorConstructor.h"
#include "ErrorPrototype.h"
#include "FunctionConstructor.h"
#include "FunctionPrototype.h"
#include "GlobalEvalFunction.h"
#include "JSGlobalObjectFunctions.h"
#include "JSLock.h"
#include "Interpreter.h"
#include "MathObject.h"
#include "NativeErrorConstructor.h"
#include "NativeErrorPrototype.h"
#include "NumberConstructor.h"
#include "NumberPrototype.h"
#include "ObjectConstructor.h"
#include "ObjectPrototype.h"
#include "Profiler.h"
#include "PrototypeFunction.h"
#include "RegExpConstructor.h"
#include "RegExpMatchesArray.h"
#include "RegExpObject.h"
#include "RegExpPrototype.h"
#include "ScopeChainMark.h"
#include "StringConstructor.h"
#include "StringPrototype.h"
#include "Debugger.h"

namespace JSC {

ASSERT_CLASS_FITS_IN_CELL(JSGlobalObject);

// Default number of ticks before a timeout check should be done.
static const int initialTickCountThreshold = 255;

// Preferred number of milliseconds between each timeout check
static const int preferredScriptCheckTimeInterval = 1000;

static inline void markIfNeeded(JSValuePtr v)
{
    if (v && !v.marked())
        v.mark();
}

static inline void markIfNeeded(const RefPtr<Structure>& s)
{
    if (s)
        s->mark();
}

JSGlobalObject::~JSGlobalObject()
{
    ASSERT(JSLock::currentThreadIsHoldingLock());

    if (d()->debugger)
        d()->debugger->detach(this);

    Profiler** profiler = Profiler::enabledProfilerReference();
    if (UNLIKELY(*profiler != 0)) {
        (*profiler)->stopProfiling(globalExec(), UString());
    }

    d()->next->d()->prev = d()->prev;
    d()->prev->d()->next = d()->next;
    JSGlobalObject*& headObject = head();
    if (headObject == this)
        headObject = d()->next;
    if (headObject == this)
        headObject = 0;

    HashSet<ProgramCodeBlock*>::const_iterator end = codeBlocks().end();
    for (HashSet<ProgramCodeBlock*>::const_iterator it = codeBlocks().begin(); it != end; ++it)
        (*it)->clearGlobalObject();
        
    RegisterFile& registerFile = globalData()->interpreter->registerFile();
    if (registerFile.globalObject() == this) {
        registerFile.setGlobalObject(0);
        registerFile.setNumGlobals(0);
    }
    delete d();
}

void JSGlobalObject::init(JSObject* thisValue)
{
    ASSERT(JSLock::currentThreadIsHoldingLock());

    d()->globalData = Heap::heap(this)->globalData();
    d()->globalScopeChain = ScopeChain(this, d()->globalData.get(), thisValue);

    JSGlobalObject::globalExec()->init(0, 0, d()->globalScopeChain.node(), CallFrame::noCaller(), 0, 0, 0);

    if (JSGlobalObject*& headObject = head()) {
        d()->prev = headObject;
        d()->next = headObject->d()->next;
        headObject->d()->next->d()->prev = this;
        headObject->d()->next = this;
    } else
        headObject = d()->next = d()->prev = this;

    d()->recursion = 0;
    d()->debugger = 0;

    d()->profileGroup = 0;

    reset(prototype());
}

void JSGlobalObject::put(ExecState* exec, const Identifier& propertyName, JSValuePtr value, PutPropertySlot& slot)
{
    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));

    if (symbolTablePut(propertyName, value))
        return;
    JSVariableObject::put(exec, propertyName, value, slot);
}

void JSGlobalObject::putWithAttributes(ExecState* exec, const Identifier& propertyName, JSValuePtr value, unsigned attributes)
{
    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));

    if (symbolTablePutWithAttributes(propertyName, value, attributes))
        return;

    JSValuePtr valueBefore = getDirect(propertyName);
    PutPropertySlot slot;
    JSVariableObject::put(exec, propertyName, value, slot);
    if (!valueBefore) {
        JSValuePtr valueAfter = getDirect(propertyName);
        if (valueAfter)
            putDirect(propertyName, valueAfter, attributes);
    }
}

void JSGlobalObject::defineGetter(ExecState* exec, const Identifier& propertyName, JSObject* getterFunc)
{
    PropertySlot slot;
    if (!symbolTableGet(propertyName, slot))
        JSVariableObject::defineGetter(exec, propertyName, getterFunc);
}

void JSGlobalObject::defineSetter(ExecState* exec, const Identifier& propertyName, JSObject* setterFunc)
{
    PropertySlot slot;
    if (!symbolTableGet(propertyName, slot))
        JSVariableObject::defineSetter(exec, propertyName, setterFunc);
}

static inline JSObject* lastInPrototypeChain(JSObject* object)
{
    JSObject* o = object;
    while (o->prototype().isObject())
        o = asObject(o->prototype());
    return o;
}

void JSGlobalObject::reset(JSValuePtr prototype)
{
    ExecState* exec = JSGlobalObject::globalExec();

    // Prototypes

    d()->functionPrototype = new (exec) FunctionPrototype(exec, FunctionPrototype::createStructure(jsNull())); // The real prototype will be set once ObjectPrototype is created.
    d()->prototypeFunctionStructure = PrototypeFunction::createStructure(d()->functionPrototype);
    d()->functionPrototype->addFunctionProperties(exec, d()->prototypeFunctionStructure.get());
    d()->objectPrototype = new (exec) ObjectPrototype(exec, ObjectPrototype::createStructure(jsNull()), d()->prototypeFunctionStructure.get());
    d()->functionPrototype->structure()->setPrototypeWithoutTransition(d()->objectPrototype);

    d()->emptyObjectStructure = d()->objectPrototype->inheritorID();

    d()->functionStructure = JSFunction::createStructure(d()->functionPrototype);
    d()->callbackFunctionStructure = JSCallbackFunction::createStructure(d()->functionPrototype);
    d()->argumentsStructure = Arguments::createStructure(d()->objectPrototype);
    d()->callbackConstructorStructure = JSCallbackConstructor::createStructure(d()->objectPrototype);
    d()->callbackObjectStructure = JSCallbackObject<JSObject>::createStructure(d()->objectPrototype);

    d()->arrayPrototype = new (exec) ArrayPrototype(ArrayPrototype::createStructure(d()->objectPrototype));
    d()->arrayStructure = JSArray::createStructure(d()->arrayPrototype);
    d()->regExpMatchesArrayStructure = RegExpMatchesArray::createStructure(d()->arrayPrototype);

    d()->stringPrototype = new (exec) StringPrototype(exec, StringPrototype::createStructure(d()->objectPrototype));
    d()->stringObjectStructure = StringObject::createStructure(d()->stringPrototype);