C++ QScriptEnginePrivate::scriptValueFromJSCValue方法代码示例

bool ClassObjectDelegate::getOwnPropertySlot(QScriptObject* object,
                                             JSC::ExecState *exec,
                                             const JSC::Identifier &propertyName,
                                             JSC::PropertySlot &slot)
{
    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScript::SaveFrameHelper saveFrame(engine, exec);
    // for compatibility with the old back-end, normal JS properties
    // are queried first.
    if (QScriptObjectDelegate::getOwnPropertySlot(object, exec, propertyName, slot))
        return true;

    QScriptValue scriptObject = engine->scriptValueFromJSCValue(object);
    QScriptString scriptName;
    QScriptStringPrivate scriptName_d(engine, propertyName, QScriptStringPrivate::StackAllocated);
    QScriptStringPrivate::init(scriptName, &scriptName_d);
    uint id = 0;
    QScriptClass::QueryFlags flags = m_scriptClass->queryProperty(
        scriptObject, scriptName, QScriptClass::HandlesReadAccess, &id);
    if (flags & QScriptClass::HandlesReadAccess) {
        QScriptValue value = m_scriptClass->property(scriptObject, scriptName, id);
        slot.setValue(engine->scriptValueToJSCValue(value));
        return true;
    }
    return false;
}

bool ClassObjectDelegate::getOwnPropertySlot(QScriptObject* object,
                                             JSC::ExecState *exec,
                                             const JSC::Identifier &propertyName,
                                             JSC::PropertySlot &slot)
{
    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScript::SaveFrameHelper saveFrame(engine, exec);
    // for compatibility with the old back-end, normal JS properties
    // are queried first.
    if (QScriptObjectDelegate::getOwnPropertySlot(object, exec, propertyName, slot))
        return true;

    QScriptValue scriptObject = engine->scriptValueFromJSCValue(object);
    QScriptString scriptName;
    QScriptStringPrivate scriptName_d(engine, propertyName, QScriptStringPrivate::StackAllocated);
    QScriptStringPrivate::init(scriptName, &scriptName_d);
    uint id = 0;
    QScriptClass::QueryFlags flags = m_scriptClass->queryProperty(
        scriptObject, scriptName, QScriptClass::HandlesReadAccess, &id);
    if (flags & QScriptClass::HandlesReadAccess) {
        QScriptValue value = m_scriptClass->property(scriptObject, scriptName, id);
        if (!value.isValid()) {
            // The class claims to have the property, but returned an invalid
            // value. Silently convert to undefined to avoid the invalid value
            // "escaping" into JS.
            value = QScriptValue(QScriptValue::UndefinedValue);
        }
        slot.setValue(engine->scriptValueToJSCValue(value));
        return true;
    }
    return false;
}

bool ClassObjectDelegate::getPropertyAttributes(const QScriptObject* object, JSC::ExecState *exec,
                                                const JSC::Identifier &propertyName,
                                                unsigned &attribs) const
{
    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScript::SaveFrameHelper saveFrame(engine, exec);
    QScriptValue scriptObject = engine->scriptValueFromJSCValue(object);
    QScriptString scriptName;
    QScriptStringPrivate scriptName_d(engine, propertyName, QScriptStringPrivate::StackAllocated);
    QScriptStringPrivate::init(scriptName, &scriptName_d);
    uint id = 0;
    QScriptClass::QueryFlags flags = m_scriptClass->queryProperty(
        scriptObject, scriptName, QScriptClass::HandlesReadAccess, &id);
    if (flags & QScriptClass::HandlesReadAccess) {
        QScriptValue::PropertyFlags flags = m_scriptClass->propertyFlags(scriptObject, scriptName, id);
        attribs = 0;
        if (flags & QScriptValue::ReadOnly)
            attribs |= JSC::ReadOnly;
        if (flags & QScriptValue::SkipInEnumeration)
            attribs |= JSC::DontEnum;
        if (flags & QScriptValue::Undeletable)
            attribs |= JSC::DontDelete;
        if (flags & QScriptValue::PropertyGetter)
            attribs |= JSC::Getter;
        if (flags & QScriptValue::PropertySetter)
            attribs |= JSC::Setter;
        attribs |= flags & QScriptValue::UserRange;
        return true;
    }
    return QScriptObjectDelegate::getPropertyAttributes(object, exec, propertyName, attribs);
}

void ClassObjectDelegate::put(QScriptObject* object, JSC::ExecState *exec,
                              const JSC::Identifier &propertyName,
                              JSC::JSValue value, JSC::PutPropertySlot &slot)
{
    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScript::SaveFrameHelper saveFrame(engine, exec);
    QScriptValue scriptObject = engine->scriptValueFromJSCValue(object);
    QScriptString scriptName;
    QScriptStringPrivate scriptName_d(engine, propertyName, QScriptStringPrivate::StackAllocated);
    QScriptStringPrivate::init(scriptName, &scriptName_d);
    uint id = 0;
    QScriptClass::QueryFlags flags = m_scriptClass->queryProperty(
        scriptObject, scriptName, QScriptClass::HandlesWriteAccess, &id);
    if (flags & QScriptClass::HandlesWriteAccess) {
        m_scriptClass->setProperty(scriptObject, scriptName, id, engine->scriptValueFromJSCValue(value));
        return;
    }
    QScriptObjectDelegate::put(object, exec, propertyName, value, slot);
}

/*!
  Returns the `this' object associated with this QScriptContext.
*/
QScriptValue QScriptContext::thisObject() const
{
    JSC::CallFrame *frame = const_cast<JSC::ExecState*>(QScriptEnginePrivate::frameForContext(this));
    QScriptEnginePrivate *engine = QScript::scriptEngineFromExec(frame);
    QScript::APIShim shim(engine);
    JSC::JSValue result = engine->thisForContext(frame);
    if (!result || result.isNull())
        result = frame->globalThisValue();
    return engine->scriptValueFromJSCValue(result);
}

/*!
  Returns the callee. The callee is the function object that this
  QScriptContext represents an invocation of.
*/
QScriptValue QScriptContext::callee() const
{
    const JSC::CallFrame *frame = QScriptEnginePrivate::frameForContext(this);
    QScriptEnginePrivate *eng = QScript::scriptEngineFromExec(frame);
    QScript::APIShim shim(eng);
    if (frame->callee() == eng->originalGlobalObject()) {
        // This is a pushContext()-created context; the callee is a lie.
        Q_ASSERT(QScriptEnginePrivate::contextFlags(const_cast<JSC::CallFrame*>(frame)) & QScriptEnginePrivate::NativeContext);
        return QScriptValue();
    }
    return eng->scriptValueFromJSCValue(frame->callee());
}

QScriptValue QScriptDeclarativeClass::newObject(QScriptEngine *engine, 
                                                QScriptDeclarativeClass *scriptClass, 
                                                Object *object)
{
    Q_ASSERT(engine);
    Q_ASSERT(scriptClass);

    QScriptEnginePrivate *p = static_cast<QScriptEnginePrivate *>(QObjectPrivate::get(engine)); 

    JSC::ExecState* exec = p->currentFrame;
    QScriptObject *result = new (exec) QScriptObject(p->scriptObjectStructure);
    result->setDelegate(new QScript::DeclarativeObjectDelegate(scriptClass, object));
    return p->scriptValueFromJSCValue(result);
}

bool ClassObjectDelegate::getOwnPropertyDescriptor(QScriptObject *object,
                                                   JSC::ExecState *exec,
                                                   const JSC::Identifier &propertyName,
                                                   JSC::PropertyDescriptor &descriptor)
{
    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScript::SaveFrameHelper saveFrame(engine, exec);
    // for compatibility with the old back-end, normal JS properties
    // are queried first.
    if (QScriptObjectDelegate::getOwnPropertyDescriptor(object, exec, propertyName, descriptor))
        return true;

    QScriptValue scriptObject = engine->scriptValueFromJSCValue(object);
    QScriptString scriptName;
    QScriptStringPrivate scriptName_d(engine, propertyName, QScriptStringPrivate::StackAllocated);
    QScriptStringPrivate::init(scriptName, &scriptName_d);
    uint id = 0;
    QScriptClass::QueryFlags qflags = m_scriptClass->queryProperty(
        scriptObject, scriptName, QScriptClass::HandlesReadAccess, &id);
    if (qflags & QScriptClass::HandlesReadAccess) {
        QScriptValue::PropertyFlags pflags = m_scriptClass->propertyFlags(scriptObject, scriptName, id);
        unsigned attribs = 0;
        if (pflags & QScriptValue::ReadOnly)
            attribs |= JSC::ReadOnly;
        if (pflags & QScriptValue::SkipInEnumeration)
            attribs |= JSC::DontEnum;
        if (pflags & QScriptValue::Undeletable)
            attribs |= JSC::DontDelete;
        if (pflags & QScriptValue::PropertyGetter)
            attribs |= JSC::Getter;
        if (pflags & QScriptValue::PropertySetter)
            attribs |= JSC::Setter;
        attribs |= pflags & QScriptValue::UserRange;
        // Rather than calling the getter, we could return an access descriptor here.
        QScriptValue value = m_scriptClass->property(scriptObject, scriptName, id);
        if (!value.isValid()) {
            // The class claims to have the property, but returned an invalid
            // value. Silently convert to undefined to avoid the invalid value
            // "escaping" into JS.
            value = QScriptValue(QScriptValue::UndefinedValue);
        }
        descriptor.setDescriptor(engine->scriptValueToJSCValue(value), attribs);
        return true;
    }
    return false;
}

/*!
  \internal
  \since 4.5

  Removes the front object from this context's scope chain, and
  returns the removed object.

  If the scope chain is already empty, this function returns an
  invalid QScriptValue.
*/
QScriptValue QScriptContext::popScope()
{
    activationObject(); //ensure the creation of the normal scope for native context
    JSC::CallFrame *frame = QScriptEnginePrivate::frameForContext(this);
    JSC::ScopeChainNode *scope = frame->scopeChain();
    Q_ASSERT(scope != 0);
    QScriptEnginePrivate *engine = QScript::scriptEngineFromExec(frame);
    QScript::APIShim shim(engine);
    QScriptValue result = engine->scriptValueFromJSCValue(scope->object);
    if (!scope->next) {
        // We cannot have a null scope chain, so just zap the object pointer.
        scope->object = 0;
    } else {
        frame->setScopeChain(scope->pop());
    }
    return result;
}

void ClassObjectDelegate::getOwnPropertyNames(QScriptObject* object, JSC::ExecState *exec,
                                              JSC::PropertyNameArray &propertyNames,
                                              bool includeNonEnumerable)
{
    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScript::SaveFrameHelper saveFrame(engine, exec);
    QScriptValue scriptObject = engine->scriptValueFromJSCValue(object);
    QScriptClassPropertyIterator *it = m_scriptClass->newIterator(scriptObject);
    if (it != 0) {
        while (it->hasNext()) {
            it->next();
            QString name = it->name().toString();
            propertyNames.add(JSC::Identifier(exec, name));
        }
        delete it;
    }
    QScriptObjectDelegate::getOwnPropertyNames(object, exec, propertyNames, includeNonEnumerable);
}

/*
Returns the scope chain entry at \a index.  If index is less than 0, returns
entries starting at the end.  For example, scopeChainValue(context, -1) will return
the value last in the scope chain.
*/
QScriptValue QScriptDeclarativeClass::scopeChainValue(QScriptContext *context, int index)
{
    context->activationObject(); //ensure the creation of the normal scope for native context
    const JSC::CallFrame *frame = QScriptEnginePrivate::frameForContext(context);
    QScriptEnginePrivate *engine = QScript::scriptEngineFromExec(frame);
    QScript::APIShim shim(engine);

    JSC::ScopeChainNode *node = frame->scopeChain();
    JSC::ScopeChainIterator it(node);

    if (index < 0) {
        int count = 0;
        for (it = node->begin(); it != node->end(); ++it) 
            ++count;

        index = qAbs(index);
        if (index > count)
            return QScriptValue();
        else
            index = count - index;
    }

    for (it = node->begin(); it != node->end(); ++it) {

        if (index == 0) {

            JSC::JSObject *object = *it;
            if (!object) return QScriptValue();

            if (object->inherits(&QScript::QScriptActivationObject::info)
                    && (static_cast<QScript::QScriptActivationObject*>(object)->delegate() != 0)) {
                // Return the object that property access is being delegated to
                object = static_cast<QScript::QScriptActivationObject*>(object)->delegate();
            }
            return engine->scriptValueFromJSCValue(object);

        } else {
            --index;
        }

    }

    return QScriptValue();
}

void DeclarativeObjectDelegate::put(QScriptObject* object, JSC::ExecState *exec,
                                    const JSC::Identifier &propertyName,
                                    JSC::JSValue value, JSC::PutPropertySlot &slot)
{
    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScriptDeclarativeClass::Identifier identifier = (void *)propertyName.ustring().rep();

    QScriptDeclarativeClassPrivate *p = QScriptDeclarativeClassPrivate::get(m_class);
    p->context = reinterpret_cast<QScriptContext *>(exec);
    QScriptClass::QueryFlags flags =
        m_class->queryProperty(m_object, identifier, QScriptClass::HandlesWriteAccess);
    if (flags & QScriptClass::HandlesWriteAccess) {
        m_class->setProperty(m_object, identifier, engine->scriptValueFromJSCValue(value));
        p->context = 0;
        return;
    }
    p->context = 0;

    QScriptObjectDelegate::put(object, exec, propertyName, value, slot);
}

void ClassObjectDelegate::getOwnPropertyNames(QScriptObject* object, JSC::ExecState *exec,
                                              JSC::PropertyNameArray &propertyNames,
                                              JSC::EnumerationMode mode)
{
    // For compatibility with the old back-end, normal JS properties
    // are added first.
    QScriptObjectDelegate::getOwnPropertyNames(object, exec, propertyNames, mode);

    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScript::SaveFrameHelper saveFrame(engine, exec);
    QScriptValue scriptObject = engine->scriptValueFromJSCValue(object);
    QScriptClassPropertyIterator *it = m_scriptClass->newIterator(scriptObject);
    if (it != 0) {
        while (it->hasNext()) {
            it->next();
            QString name = it->name().toString();
            propertyNames.add(JSC::Identifier(exec, name));
        }
        delete it;
    }
}

bool ClassObjectDelegate::deleteProperty(QScriptObject* object, JSC::ExecState *exec,
                                         const JSC::Identifier &propertyName)
{
    // ### avoid duplication of put()
    QScriptEnginePrivate *engine = scriptEngineFromExec(exec);
    QScript::SaveFrameHelper saveFrame(engine, exec);
    QScriptValue scriptObject = engine->scriptValueFromJSCValue(object);
    QScriptString scriptName;
    QScriptStringPrivate scriptName_d(engine, propertyName, QScriptStringPrivate::StackAllocated);
    QScriptStringPrivate::init(scriptName, &scriptName_d);
    uint id = 0;
    QScriptClass::QueryFlags flags = m_scriptClass->queryProperty(
        scriptObject, scriptName, QScriptClass::HandlesWriteAccess, &id);
    if (flags & QScriptClass::HandlesWriteAccess) {
        if (m_scriptClass->propertyFlags(scriptObject, scriptName, id) & QScriptValue::Undeletable)
            return false;
        m_scriptClass->setProperty(scriptObject, scriptName, id, QScriptValue());
        return true;
    }
    return QScriptObjectDelegate::deleteProperty(object, exec, propertyName);
}

/*!
  \internal
  \since 4.5

  Returns the scope chain of this QScriptContext.
*/
QScriptValueList QScriptContext::scopeChain() const
{
    activationObject(); //ensure the creation of the normal scope for native context
    const JSC::CallFrame *frame = QScriptEnginePrivate::frameForContext(this);
    QScriptEnginePrivate *engine = QScript::scriptEngineFromExec(frame);
    QScript::APIShim shim(engine);
    QScriptValueList result;
    JSC::ScopeChainNode *node = frame->scopeChain();
    JSC::ScopeChainIterator it(node);
    for (it = node->begin(); it != node->end(); ++it) {
        JSC::JSObject *object = *it;
        if (!object)
            continue;
        if (object->inherits(&QScript::QScriptActivationObject::info)
            && (static_cast<QScript::QScriptActivationObject*>(object)->delegate() != 0)) {
            // Return the object that property access is being delegated to
            object = static_cast<QScript::QScriptActivationObject*>(object)->delegate();
        }
        result.append(engine->scriptValueFromJSCValue(object));
    }
    return result;
}