Source/WebCore/bindings/js/JSWindowProxy.cpp

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#include "config.h"
#include "JSWindowProxy.h"

#include "AbstractFrame.h"
#include "CommonVM.h"
#include "GCController.h"
#include "JSDOMWindow.h"
#include "JSDOMWindowProperties.h"
#include "JSEventTarget.h"
#include "JSRemoteDOMWindow.h"
#include "ScriptController.h"
#include <JavaScriptCore/Debugger.h>
#include <JavaScriptCore/JSObject.h>
#include <JavaScriptCore/StrongInlines.h>

namespace WebCore {

using namespace JSC;

const ClassInfo JSWindowProxy::s_info = { "JSWindowProxy", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(JSWindowProxy) };

inline JSWindowProxy::JSWindowProxy(VM& vm, Structure& structure, DOMWrapperWorld& world)
    : Base(vm, &structure)
    , m_world(world)
{
}

void JSWindowProxy::finishCreation(VM& vm, AbstractDOMWindow& window)
{
    Base::finishCreation(vm);
    ASSERT(inherits(vm, info()));
    setWindow(window);
}

JSWindowProxy& JSWindowProxy::create(VM& vm, AbstractDOMWindow& window, DOMWrapperWorld& world)
{
    auto& structure = *Structure::create(vm, 0, jsNull(), TypeInfo(PureForwardingProxyType, StructureFlags), info());
    auto& proxy = *new (NotNull, allocateCell<JSWindowProxy>(vm.heap)) JSWindowProxy(vm, structure, world);
    proxy.finishCreation(vm, window);
    return proxy;
}

void JSWindowProxy::destroy(JSCell* cell)
{
    static_cast<JSWindowProxy*>(cell)->JSWindowProxy::~JSWindowProxy();
}

void JSWindowProxy::setWindow(VM& vm, JSDOMGlobalObject& window)
{
    ASSERT(window.classInfo() == JSDOMWindow::info() || window.classInfo() == JSRemoteDOMWindow::info());
    setTarget(vm, &window);
    structure(vm)->setGlobalObject(vm, &window);
    GCController::singleton().garbageCollectSoon();
}

void JSWindowProxy::setWindow(AbstractDOMWindow& domWindow)
{
    // Replacing JSDOMWindow via telling JSWindowProxy to use the same DOMWindow it already uses makes no sense,
    // so we'd better never try to.
    ASSERT(!window() || &domWindow != &wrapped());

    bool isRemoteDOMWindow = is<RemoteDOMWindow>(domWindow);

    VM& vm = commonVM();
    auto& prototypeStructure = isRemoteDOMWindow ? *JSRemoteDOMWindowPrototype::createStructure(vm, nullptr, jsNull()) : *JSDOMWindowPrototype::createStructure(vm, nullptr, jsNull());

    // Explicitly protect the prototype so it isn't collected when we allocate the global object.
    // (Once the global object is fully constructed, it will mark its own prototype.)
    // FIXME: Why do we need to protect this when there's a pointer to it on the stack?
    // Perhaps the issue is that structure objects aren't seen when scanning the stack?
    Strong<JSNonFinalObject> prototype(vm, isRemoteDOMWindow ? static_cast<JSNonFinalObject*>(JSRemoteDOMWindowPrototype::create(vm, nullptr, &prototypeStructure)) : static_cast<JSNonFinalObject*>(JSDOMWindowPrototype::create(vm, nullptr, &prototypeStructure)));

    JSDOMGlobalObject* window = nullptr;
    if (isRemoteDOMWindow) {
        auto& windowStructure = *JSRemoteDOMWindow::createStructure(vm, nullptr, prototype.get());
        window = JSRemoteDOMWindow::create(vm, &windowStructure, downcast<RemoteDOMWindow>(domWindow), this);
    } else {
        auto& windowStructure = *JSDOMWindow::createStructure(vm, nullptr, prototype.get());
        window = JSDOMWindow::create(vm, &windowStructure, downcast<DOMWindow>(domWindow), this);
    }

    prototype->structure(vm)->setGlobalObject(vm, window);

    auto& propertiesStructure = *JSDOMWindowProperties::createStructure(vm, window, JSEventTarget::prototype(vm, *window));
    auto& properties = *JSDOMWindowProperties::create(&propertiesStructure, *window);
    properties.didBecomePrototype();
    prototype->structure(vm)->setPrototypeWithoutTransition(vm, &properties);

    setWindow(vm, *window);

    ASSERT(window->globalObject() == window);
    ASSERT(prototype->globalObject() == window);
}

WindowProxy* JSWindowProxy::windowProxy() const
{
    auto& window = wrapped();
    return window.frame() ? &window.frame()->windowProxy() : nullptr;
}

void JSWindowProxy::attachDebugger(JSC::Debugger* debugger)
{
    auto* globalObject = window();
    JSLockHolder lock(globalObject->vm());

    if (debugger)
        debugger->attach(globalObject);
    else if (auto* currentDebugger = globalObject->debugger())
        currentDebugger->detach(globalObject, JSC::Debugger::TerminatingDebuggingSession);
}

AbstractDOMWindow& JSWindowProxy::wrapped() const
{
    auto* window = this->window();
    if (auto* jsWindow = jsDynamicCast<JSRemoteDOMWindowBase*>(window->vm(), window))
        return jsWindow->wrapped();
    return jsCast<JSDOMWindowBase*>(window)->wrapped();
}

JSValue toJS(JSGlobalObject* lexicalGlobalObject, WindowProxy& windowProxy)
{
    auto* jsWindowProxy = windowProxy.jsWindowProxy(currentWorld(*lexicalGlobalObject));
    return jsWindowProxy ? JSValue(jsWindowProxy) : jsNull();
}

JSWindowProxy* toJSWindowProxy(WindowProxy& windowProxy, DOMWrapperWorld& world)
{
    return windowProxy.jsWindowProxy(world);
}

WindowProxy* JSWindowProxy::toWrapped(VM& vm, JSValue value)
{
    if (!value.isObject())
        return nullptr;
    JSObject* object = asObject(value);
    if (object->inherits<JSWindowProxy>(vm))
        return jsCast<JSWindowProxy*>(object)->windowProxy();
    return nullptr;
}

} // namespace WebCore