C++ MutableHandle::object方法代码示例

bool
BaseDOMProxyHandler::getPropertyDescriptor(JSContext* cx,
                                           JS::Handle<JSObject*> proxy,
                                           JS::Handle<jsid> id,
                                           MutableHandle<JSPropertyDescriptor> desc,
                                           unsigned flags)
{
  if (!getOwnPropertyDescriptor(cx, proxy, id, desc, flags)) {
    return false;
  }
  if (desc.object()) {
    return true;
  }

  JS::Rooted<JSObject*> proto(cx);
  if (!js::GetObjectProto(cx, proxy, &proto)) {
    return false;
  }
  if (!proto) {
    desc.object().set(nullptr);
    return true;
  }

  return JS_GetPropertyDescriptorById(cx, proto, id, 0, desc);
}

bool
ModuleNamespaceObject::ProxyHandler::getOwnPropertyDescriptor(JSContext* cx, HandleObject proxy,
                                                              HandleId id,
                                                              MutableHandle<PropertyDescriptor> desc) const
{
    Rooted<ModuleNamespaceObject*> ns(cx, &proxy->as<ModuleNamespaceObject>());
    if (JSID_IS_SYMBOL(id)) {
        Rooted<JS::Symbol*> symbol(cx, JSID_TO_SYMBOL(id));
        if (symbol == cx->wellKnownSymbols().iterator) {
            RootedValue enumerateFun(cx, getEnumerateFunction(proxy));
            desc.object().set(proxy);
            desc.setConfigurable(false);
            desc.setEnumerable(false);
            desc.setValue(enumerateFun);
            return true;
        }

        if (symbol == cx->wellKnownSymbols().toStringTag) {
            RootedValue value(cx, StringValue(cx->names().Module));
            desc.object().set(proxy);
            desc.setWritable(false);
            desc.setEnumerable(false);
            desc.setConfigurable(true);
            desc.setValue(value);
            return true;
        }

        return true;
    }

    const IndirectBindingMap& bindings = ns->bindings();
    ModuleEnvironmentObject* env;
    Shape* shape;
    if (!bindings.lookup(id, &env, &shape))
        return true;

    RootedValue value(cx, env->getSlot(shape->slot()));
    if (value.isMagic(JS_UNINITIALIZED_LEXICAL)) {
        ReportRuntimeLexicalError(cx, JSMSG_UNINITIALIZED_LEXICAL, id);
        return false;
    }

    desc.object().set(env);
    desc.setConfigurable(false);
    desc.setEnumerable(true);
    desc.setValue(value);
    return true;
}

bool
JavaScriptShared::toDescriptor(JSContext* cx, const PPropertyDescriptor& in,
                               MutableHandle<JSPropertyDescriptor> out)
{
    out.setAttributes(in.attrs());
    if (!fromVariant(cx, in.value(), out.value()))
        return false;
    out.object().set(fromObjectOrNullVariant(cx, in.obj()));

    if (in.getter().type() == GetterSetter::Tuint64_t && !in.getter().get_uint64_t()) {
        out.setGetter(nullptr);
    } else if (in.attrs() & JSPROP_GETTER) {
        Rooted<JSObject*> getter(cx);
        getter = fromObjectVariant(cx, in.getter().get_ObjectVariant());
        if (!getter)
            return false;
        out.setGetter(JS_DATA_TO_FUNC_PTR(JSGetterOp, getter.get()));
    } else {
        out.setGetter(UnknownPropertyStub);
    }

    if (in.setter().type() == GetterSetter::Tuint64_t && !in.setter().get_uint64_t()) {
        out.setSetter(nullptr);
    } else if (in.attrs() & JSPROP_SETTER) {
        Rooted<JSObject*> setter(cx);
        setter = fromObjectVariant(cx, in.setter().get_ObjectVariant());
        if (!setter)
            return false;
        out.setSetter(JS_DATA_TO_FUNC_PTR(JSSetterOp, setter.get()));
    } else {
        out.setSetter(UnknownStrictPropertyStub);
    }

    return true;
}

bool
OpaqueCrossCompartmentWrapper::getOwnPropertyDescriptor(JSContext* cx,
                                                        HandleObject wrapper,
                                                        HandleId id,
                                                        MutableHandle<PropertyDescriptor> desc) const
{
    desc.object().set(nullptr);
    return true;
}

bool
js::SetPropertyIgnoringNamedGetter(JSContext* cx, const BaseProxyHandler* handler,
                                   HandleObject proxy, HandleObject receiver,
                                   HandleId id, MutableHandle<PropertyDescriptor> desc,
                                   bool descIsOwn, bool strict, MutableHandleValue vp)
{
    /* The control-flow here differs from ::get() because of the fall-through case below. */
    MOZ_ASSERT_IF(descIsOwn, desc.object());
    if (desc.object()) {
        MOZ_ASSERT(desc.getter() != JS_PropertyStub);
        MOZ_ASSERT(desc.setter() != JS_StrictPropertyStub);

        // Check for read-only properties.
        if (desc.isReadonly()) {
            if (strict)
                return Throw(cx, id, descIsOwn ? JSMSG_READ_ONLY : JSMSG_CANT_REDEFINE_PROP);
            return true;
        }

        if (desc.hasSetterObject() || desc.setter()) {
            if (!CallSetter(cx, receiver, id, desc.setter(), desc.attributes(), strict, vp))
                return false;
            if (!proxy->is<ProxyObject>() || proxy->as<ProxyObject>().handler() != handler)
                return true;
            if (desc.isShared())
                return true;
        }
        desc.value().set(vp.get());

        if (descIsOwn) {
            MOZ_ASSERT(desc.object() == proxy);
            return handler->defineProperty(cx, proxy, id, desc);
        }
        return DefineProperty(cx, receiver, id, desc.value(),
                              desc.getter(), desc.setter(), desc.attributes());
    }
    desc.object().set(receiver);
    desc.value().set(vp.get());
    desc.setAttributes(JSPROP_ENUMERATE);
    desc.setGetter(nullptr);
    desc.setSetter(nullptr); // Pick up the class getter/setter.
    return DefineProperty(cx, receiver, id, desc.value(), nullptr, nullptr, JSPROP_ENUMERATE);
}

bool
BaseProxyHandler::getPropertyDescriptor(JSContext* cx, HandleObject proxy, HandleId id,
                                        MutableHandle<PropertyDescriptor> desc) const
{
    assertEnteredPolicy(cx, proxy, id, GET | SET | GET_PROPERTY_DESCRIPTOR);

    if (!getOwnPropertyDescriptor(cx, proxy, id, desc))
        return false;
    if (desc.object())
        return true;

    RootedObject proto(cx);
    if (!GetPrototype(cx, proxy, &proto))
        return false;
    if (!proto) {
        MOZ_ASSERT(!desc.object());
        return true;
    }
    return GetPropertyDescriptor(cx, proto, id, desc);
}

bool
AddonWrapper<Base>::getOwnPropertyDescriptor(JSContext* cx, HandleObject wrapper,
                                             HandleId id, MutableHandle<JSPropertyDescriptor> desc) const
{
    if (!InterposeProperty(cx, wrapper, nullptr, id, desc))
        return false;

    if (desc.object())
        return true;

    return Base::getOwnPropertyDescriptor(cx, wrapper, id, desc);
}

bool
Proxy::getOwnPropertyDescriptor(JSContext* cx, HandleObject proxy, HandleId id,
                                MutableHandle<PropertyDescriptor> desc)
{
    if (!CheckRecursionLimit(cx))
        return false;
    const BaseProxyHandler* handler = proxy->as<ProxyObject>().handler();
    desc.object().set(nullptr); // default result if we refuse to perform this action
    AutoEnterPolicy policy(cx, handler, proxy, id, BaseProxyHandler::GET_PROPERTY_DESCRIPTOR, true);
    if (!policy.allowed())
        return policy.returnValue();
    return handler->getOwnPropertyDescriptor(cx, proxy, id, desc);
}

bool
JSCompartment::wrap(JSContext* cx, MutableHandle<PropertyDescriptor> desc)
{
    if (!wrap(cx, desc.object()))
        return false;

    if (desc.hasGetterObject()) {
        if (!wrap(cx, desc.getterObject()))
            return false;
    }
    if (desc.hasSetterObject()) {
        if (!wrap(cx, desc.setterObject()))
            return false;
    }

    return wrap(cx, desc.value());
}

bool
JavaScriptShared::toDescriptor(JSContext *cx, const PPropertyDescriptor &in,
                               MutableHandle<JSPropertyDescriptor> out)
{
    out.setAttributes(in.attrs());
    out.setShortId(in.shortid());
    if (!toValue(cx, in.value(), out.value()))
        return false;
    Rooted<JSObject*> obj(cx);
    if (!unwrap(cx, in.objId(), &obj))
        return false;
    out.object().set(obj);

    if (!in.getter()) {
        out.setGetter(nullptr);
    } else if (in.attrs() & JSPROP_GETTER) {
        Rooted<JSObject*> getter(cx);
        if (!unwrap(cx, in.getter(), &getter))
            return false;
        out.setGetter(JS_DATA_TO_FUNC_PTR(JSPropertyOp, getter.get()));
    } else {
        if (in.getter() == DefaultPropertyOp)
            out.setGetter(JS_PropertyStub);
        else
            out.setGetter(UnknownPropertyStub);
    }

    if (!in.setter()) {
        out.setSetter(nullptr);
    } else if (in.attrs() & JSPROP_SETTER) {
        Rooted<JSObject*> setter(cx);
        if (!unwrap(cx, in.setter(), &setter))
            return false;
        out.setSetter(JS_DATA_TO_FUNC_PTR(JSStrictPropertyOp, setter.get()));
    } else {
        if (in.setter() == DefaultPropertyOp)
            out.setSetter(JS_StrictPropertyStub);
        else if (in.setter() == GetterOnlyPropertyStub)
            out.setSetter(js_GetterOnlyPropertyStub);
        else
            out.setSetter(UnknownStrictPropertyStub);
    }

    return true;
}

    bool impl(JSContext *cx, HandleObject proxy, HandleId id,
              MutableHandle<JSPropertyDescriptor> desc, bool ownOnly) const
    {
        if (JSID_IS_STRING(id)) {
            bool match;
            if (!JS_StringEqualsAscii(cx, JSID_TO_STRING(id), "phantom", &match))
                return false;
            if (match) {
                desc.object().set(proxy);
                desc.attributesRef() = JSPROP_READONLY | JSPROP_ENUMERATE;
                desc.value().setInt32(42);
                return true;
            }
        }

        if (ownOnly)
            return DirectProxyHandler::getOwnPropertyDescriptor(cx, proxy, id, desc);
        return DirectProxyHandler::getPropertyDescriptor(cx, proxy, id, desc);
    }

// ES6 (5 April 2014) 9.5.5 Proxy.[[GetOwnProperty]](P)
bool
ScriptedDirectProxyHandler::getOwnPropertyDescriptor(JSContext* cx, HandleObject proxy, HandleId id,
                                                     MutableHandle<PropertyDescriptor> desc) const
{
    // step 2
    RootedObject handler(cx, GetDirectProxyHandlerObject(proxy));

    // step 3
    if (!handler) {
        JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_PROXY_REVOKED);
        return false;
    }

    // step 4
    RootedObject target(cx, proxy->as<ProxyObject>().target());

    // step 5-6
    RootedValue trap(cx);
    if (!GetProperty(cx, handler, handler, cx->names().getOwnPropertyDescriptor, &trap))
        return false;

    // step 7
    if (trap.isUndefined())
        return GetOwnPropertyDescriptor(cx, target, id, desc);

    // step 8-9
    RootedValue propKey(cx);
    if (!IdToStringOrSymbol(cx, id, &propKey))
        return false;

    Value argv[] = {
        ObjectValue(*target),
        propKey
    };
    RootedValue trapResult(cx);
    if (!Invoke(cx, ObjectValue(*handler), trap, ArrayLength(argv), argv, &trapResult))
        return false;

    // step 10
    if (!trapResult.isUndefined() && !trapResult.isObject()) {
        JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_PROXY_GETOWN_OBJORUNDEF);
        return false;
    }

    //step 11-12
    Rooted<PropertyDescriptor> targetDesc(cx);
    if (!GetOwnPropertyDescriptor(cx, target, id, &targetDesc))
        return false;

    // step 13
    if (trapResult.isUndefined()) {
        // substep a
        if (!targetDesc.object()) {
            desc.object().set(nullptr);
            return true;
        }

        // substep b
        if (!targetDesc.configurable()) {
            JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_NC_AS_NE);
            return false;
        }

        // substep c-e
        bool extensibleTarget;
        if (!IsExtensible(cx, target, &extensibleTarget))
            return false;
        if (!extensibleTarget) {
            JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_E_AS_NE);
            return false;
        }

        // substep f
        desc.object().set(nullptr);
        return true;
    }

    // step 14-15
    bool extensibleTarget;
    if (!IsExtensible(cx, target, &extensibleTarget))
        return false;

    // step 16-17
    Rooted<PropertyDescriptor> resultDesc(cx);
    if (!ToPropertyDescriptor(cx, trapResult, true, &resultDesc))
        return false;

    // step 18
    CompletePropertyDescriptor(&resultDesc);

    // step 19
    bool valid;
    if (!ValidatePropertyDescriptor(cx, extensibleTarget, resultDesc, targetDesc, &valid))
        return false;

    // step 20
    if (!valid) {
        JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_INVALID);
        return false;
//.........这里部分代码省略.........

bool
js::SetPropertyIgnoringNamedGetter(JSContext *cx, const BaseProxyHandler *handler,
                                   HandleObject proxy, HandleObject receiver,
                                   HandleId id, MutableHandle<PropertyDescriptor> desc,
                                   bool descIsOwn, bool strict, MutableHandleValue vp)
{
    /* The control-flow here differs from ::get() because of the fall-through case below. */
    if (descIsOwn) {
        MOZ_ASSERT(desc.object());

        // Check for read-only properties.
        if (desc.isReadonly())
            return strict ? Throw(cx, id, JSMSG_READ_ONLY) : true;
        if (!desc.setter()) {
            // Be wary of the odd explicit undefined setter case possible through
            // Object.defineProperty.
            if (!desc.hasSetterObject())
                desc.setSetter(JS_StrictPropertyStub);
        } else if (desc.hasSetterObject() || desc.setter() != JS_StrictPropertyStub) {
            if (!CallSetter(cx, receiver, id, desc.setter(), desc.attributes(), strict, vp))
                return false;
            if (!proxy->is<ProxyObject>() || proxy->as<ProxyObject>().handler() != handler)
                return true;
            if (desc.isShared())
                return true;
        }
        if (!desc.getter()) {
            // Same as above for the null setter case.
            if (!desc.hasGetterObject())
                desc.setGetter(JS_PropertyStub);
        }
        desc.value().set(vp.get());
        return handler->defineProperty(cx, receiver, id, desc);
    }
    if (desc.object()) {
        // Check for read-only properties.
        if (desc.isReadonly())
            return strict ? Throw(cx, id, JSMSG_CANT_REDEFINE_PROP) : true;
        if (!desc.setter()) {
            // Be wary of the odd explicit undefined setter case possible through
            // Object.defineProperty.
            if (!desc.hasSetterObject())
                desc.setSetter(JS_StrictPropertyStub);
        } else if (desc.hasSetterObject() || desc.setter() != JS_StrictPropertyStub) {
            if (!CallSetter(cx, receiver, id, desc.setter(), desc.attributes(), strict, vp))
                return false;
            if (!proxy->is<ProxyObject>() || proxy->as<ProxyObject>().handler() != handler)
                return true;
            if (desc.isShared())
                return true;
        }
        if (!desc.getter()) {
            // Same as above for the null setter case.
            if (!desc.hasGetterObject())
                desc.setGetter(JS_PropertyStub);
        }
        desc.value().set(vp.get());
        return JSObject::defineGeneric(cx, receiver, id, desc.value(),
                                       desc.getter(), desc.setter(), desc.attributes());
    }
    desc.object().set(receiver);
    desc.value().set(vp.get());
    desc.setAttributes(JSPROP_ENUMERATE);
    desc.setGetter(nullptr);
    desc.setSetter(nullptr); // Pick up the class getter/setter.
    return JSObject::defineGeneric(cx, receiver, id, desc.value(), nullptr, nullptr,
                                   JSPROP_ENUMERATE);
}

// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 9.5.5 Proxy.[[GetOwnProperty]](P)
bool
ScriptedProxyHandler::getOwnPropertyDescriptor(JSContext* cx, HandleObject proxy, HandleId id,
                                               MutableHandle<PropertyDescriptor> desc) const
{
    // Steps 2-4.
    RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy));
    if (!handler) {
        JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_PROXY_REVOKED);
        return false;
    }

    // Step 5.
    RootedObject target(cx, proxy->as<ProxyObject>().target());
    MOZ_ASSERT(target);

    // Step 6.
    RootedValue trap(cx);
    if (!GetProxyTrap(cx, handler, cx->names().getOwnPropertyDescriptor, &trap))
        return false;

    // Step 7.
    if (trap.isUndefined())
        return GetOwnPropertyDescriptor(cx, target, id, desc);

    // Step 8.
    RootedValue propKey(cx);
    if (!IdToStringOrSymbol(cx, id, &propKey))
        return false;

    RootedValue trapResult(cx);
    RootedValue targetVal(cx, ObjectValue(*target));
    if (!Call(cx, trap, handler, targetVal, propKey, &trapResult))
        return false;

    // Step 9.
    if (!trapResult.isUndefined() && !trapResult.isObject())
        return js::Throw(cx, id, JSMSG_PROXY_GETOWN_OBJORUNDEF);

    // Step 10.
    Rooted<PropertyDescriptor> targetDesc(cx);
    if (!GetOwnPropertyDescriptor(cx, target, id, &targetDesc))
        return false;

    // Step 11.
    if (trapResult.isUndefined()) {
        // Step 11a.
        if (!targetDesc.object()) {
            desc.object().set(nullptr);
            return true;
        }

        // Step 11b.
        if (!targetDesc.configurable())
            return js::Throw(cx, id, JSMSG_CANT_REPORT_NC_AS_NE);

        // Steps 11c-d.
        bool extensibleTarget;
        if (!IsExtensible(cx, target, &extensibleTarget))
            return false;

        // Step 11e.
        if (!extensibleTarget)
            return js::Throw(cx, id, JSMSG_CANT_REPORT_E_AS_NE);

        // Step 11f.
        desc.object().set(nullptr);
        return true;
    }

    // Step 12.
    bool extensibleTarget;
    if (!IsExtensible(cx, target, &extensibleTarget))
        return false;

    // Step 13.
    Rooted<PropertyDescriptor> resultDesc(cx);
    if (!ToPropertyDescriptor(cx, trapResult, true, &resultDesc))
        return false;

    // Step 14.
    CompletePropertyDescriptor(&resultDesc);

    // Step 15.
    const char* errorDetails = nullptr;
    if (!IsCompatiblePropertyDescriptor(cx, extensibleTarget, resultDesc, targetDesc,
                                        &errorDetails))
        return false;

    // Step 16.
    if (errorDetails)
        return js::Throw(cx, id, JSMSG_CANT_REPORT_INVALID, errorDetails);

    // Step 17.
    if (!resultDesc.configurable()) {
        if (!targetDesc.object())
            return js::Throw(cx, id, JSMSG_CANT_REPORT_NE_AS_NC);

        if (targetDesc.configurable())
            return js::Throw(cx, id, JSMSG_CANT_REPORT_C_AS_NC);
//.........这里部分代码省略.........