Source/bindings/v8/custom/V8TypedArrayCustom.h

/*
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 * modification, are permitted provided that the following conditions are
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 *
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 * notice, this list of conditions and the following disclaimer.
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 * in the documentation and/or other materials provided with the
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#ifndef V8TypedArrayCustom_h
#define V8TypedArrayCustom_h

#include "bindings/v8/V8Binding.h"
#include "bindings/v8/V8DOMWrapper.h"
#include "bindings/v8/WrapperTypeInfo.h"
#include "bindings/v8/custom/V8ArrayBufferCustom.h"
#include "wtf/ArrayBuffer.h"
#include <v8.h>

namespace WebCore {

template<typename T>
class TypedArrayTraits
{ };

template<typename TypedArray>
class V8TypedArray {
public:
    static bool HasInstance(v8::Handle<v8::Value> value, v8::Isolate*, WrapperWorldType)
    {
        return TypedArrayTraits<TypedArray>::IsInstance(value);
    }

    static bool HasInstanceInAnyWorld(v8::Handle<v8::Value> value, v8::Isolate*)
    {
        return TypedArrayTraits<TypedArray>::IsInstance(value);
    }

    static TypedArray* toNative(v8::Handle<v8::Object>);
    static void derefObject(void*);
    static WrapperTypeInfo info;
    static const int internalFieldCount = v8DefaultWrapperInternalFieldCount;

    static v8::Handle<v8::Object> wrap(TypedArray* impl, v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
    {
        ASSERT(impl);
        ASSERT(!DOMDataStore::containsWrapper<Binding>(impl, isolate));
        return V8TypedArray<TypedArray>::createWrapper(impl, creationContext, isolate);
    }

    static v8::Handle<v8::Value> toV8(TypedArray* impl, v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
    {
        if (UNLIKELY(!impl))
            return v8NullWithCheck(isolate);
        v8::Handle<v8::Value> wrapper = DOMDataStore::getWrapper<Binding>(impl, isolate);
        if (!wrapper.IsEmpty())
            return wrapper;
        return wrap(impl, creationContext, isolate);
    }

    template<typename CallbackInfo>
    static void v8SetReturnValue(const CallbackInfo& callbackInfo, TypedArray* impl, v8::Handle<v8::Object> creationContext)
    {
        if (UNLIKELY(!impl)) {
            v8SetReturnValueNull(callbackInfo);
            return;
        }
        if (DOMDataStore::setReturnValueFromWrapper<Binding>(callbackInfo.GetReturnValue(), impl))
            return;
        v8::Handle<v8::Object> wrapper = wrap(impl, creationContext, callbackInfo.GetIsolate());
        callbackInfo.GetReturnValue().Set(wrapper);
    }

    template<typename CallbackInfo>
    static void v8SetReturnValueForMainWorld(const CallbackInfo& callbackInfo, TypedArray* impl, v8::Handle<v8::Object> creationContext)
    {
        ASSERT(worldType(callbackInfo.GetIsolate()) == MainWorld);
        if (UNLIKELY(!impl)) {
            v8SetReturnValueNull(callbackInfo);
            return;
        }
        if (DOMDataStore::setReturnValueFromWrapperForMainWorld<Binding>(callbackInfo.GetReturnValue(), impl))
            return;
        v8::Handle<v8::Value> wrapper = wrap(impl, creationContext, callbackInfo.GetIsolate());
        callbackInfo.GetReturnValue().Set(wrapper);
    }

    template<class CallbackInfo, class Wrappable>
    static void v8SetReturnValueFast(const CallbackInfo& callbackInfo, TypedArray* impl, Wrappable* wrappable)
    {
        if (UNLIKELY(!impl)) {
            v8SetReturnValueNull(callbackInfo);
            return;
        }
        if (DOMDataStore::setReturnValueFromWrapperFast<Binding>(callbackInfo.GetReturnValue(), impl, callbackInfo.Holder(), wrappable))
            return;
        v8::Handle<v8::Object> wrapper = wrap(impl, callbackInfo.Holder(), callbackInfo.GetIsolate());
        callbackInfo.GetReturnValue().Set(wrapper);
    }

    static inline void* toInternalPointer(TypedArray* impl)
    {
        return impl;
    }
private:
    typedef TypedArrayTraits<TypedArray> Traits;
    typedef typename Traits::V8Type V8Type;
    typedef V8TypedArray<TypedArray> Binding;

    static v8::Handle<v8::Object> createWrapper(PassRefPtr<TypedArray>, v8::Handle<v8::Object> creationContext, v8::Isolate*);
};

template<typename TypedArray>
class TypedArrayWrapperTraits {
public:
    static WrapperTypeInfo* info() { return &V8TypedArray<TypedArray>::info; }
};


template <typename TypedArray>
v8::Handle<v8::Object> V8TypedArray<TypedArray>::createWrapper(PassRefPtr<TypedArray> impl, v8::Handle<v8::Object> creationContext, v8::Isolate* isolate)
{
    ASSERT(impl.get());
    ASSERT(!DOMDataStore::containsWrapper<Binding>(impl.get(), isolate));

    RefPtr<ArrayBuffer> buffer = impl->buffer();
    v8::Local<v8::Value> v8Buffer = WebCore::toV8(buffer.get(), creationContext, isolate);

    ASSERT(v8Buffer->IsArrayBuffer());

    v8::Local<v8::Object> wrapper = V8Type::New(v8Buffer.As<v8::ArrayBuffer>(), impl->byteOffset(), Traits::length(impl.get()));

    V8DOMWrapper::associateObjectWithWrapper<Binding>(impl, &info, wrapper, isolate, WrapperConfiguration::Independent);
    return wrapper;
}

template <typename TypedArray>
TypedArray* V8TypedArray<TypedArray>::toNative(v8::Handle<v8::Object> object)
{
    ASSERT(Traits::IsInstance(object));
    void* typedarrayPtr = object->GetAlignedPointerFromInternalField(v8DOMWrapperObjectIndex);
    if (typedarrayPtr)
        return reinterpret_cast<TypedArray*>(typedarrayPtr);

    v8::Handle<V8Type> view = object.As<V8Type>();
    RefPtr<ArrayBuffer> arrayBuffer = V8ArrayBuffer::toNative(view->Buffer());
    RefPtr<TypedArray> typedArray = TypedArray::create(arrayBuffer, view->ByteOffset(), Traits::length(view));
    ASSERT(typedArray.get());
    V8DOMWrapper::associateObjectWithWrapper<Binding>(typedArray.release(), &info, object, v8::Isolate::GetCurrent(), WrapperConfiguration::Independent);

    typedarrayPtr = object->GetAlignedPointerFromInternalField(v8DOMWrapperObjectIndex);
    ASSERT(typedarrayPtr);
    return reinterpret_cast<TypedArray*>(typedarrayPtr);
}


template <typename TypedArray>
WrapperTypeInfo V8TypedArray<TypedArray>::info = {
    0, V8TypedArray<TypedArray>::derefObject,
    0, 0, 0, 0, 0, WrapperTypeObjectPrototype
};

template <typename TypedArray>
void V8TypedArray<TypedArray>::derefObject(void* object)
{
    static_cast<TypedArray*>(object)->deref();
}


} // namespace WebCode

#endif // V8TypedArrayCustom_h