Var DataView::EntryGetterByteOffset(RecyclableObject* function, CallInfo callInfo, ...)
{
PROBE_STACK(function->GetScriptContext(), Js::Constants::MinStackDefault);
ARGUMENTS(args, callInfo);
ScriptContext* scriptContext = function->GetScriptContext();
Assert(!(callInfo.Flags & CallFlags_New));
if (args.Info.Count == 0 || !DataView::Is(args[0]))
{
JavascriptError::ThrowTypeError(scriptContext, JSERR_This_NeedDataView);
}
DataView* dataView = DataView::FromVar(args[0]);
ArrayBuffer* arrayBuffer = dataView->GetArrayBuffer();
if (arrayBuffer == nullptr)
{
JavascriptError::ThrowTypeError(scriptContext, JSERR_NeedArrayBufferObject);
}
else if (arrayBuffer->IsDetached())
{
return TaggedInt::ToVarUnchecked(0);
}
return JavascriptNumber::ToVar(dataView->GetByteOffset(), scriptContext);
}
Var AsmJsChangeHeapBuffer(RecyclableObject * function, CallInfo callInfo, ...)
{
PROBE_STACK(function->GetScriptContext(), Js::Constants::MinStackDefault);
ARGUMENTS(args, callInfo);
ScriptContext* scriptContext = function->GetScriptContext();
Assert(!(callInfo.Flags & CallFlags_New));
if (args.Info.Count < 1 || !ArrayBuffer::Is(args[1]))
{
JavascriptError::ThrowTypeError(scriptContext, JSERR_NeedArrayBufferObject);
}
ArrayBuffer* newArrayBuffer = ArrayBuffer::FromVar(args[1]);
if (newArrayBuffer->IsDetached() || newArrayBuffer->GetByteLength() & 0xffffff || newArrayBuffer->GetByteLength() <= 0xffffff || newArrayBuffer->GetByteLength() > 0x80000000)
{
return JavascriptBoolean::ToVar(FALSE, scriptContext);
}
FrameDisplay* frame = ((ScriptFunction*)function)->GetEnvironment();
Var* moduleArrayBuffer = (Var*)frame->GetItem(0) + AsmJsModuleMemory::MemoryTableBeginOffset;
*moduleArrayBuffer = newArrayBuffer;
return JavascriptBoolean::ToVar(TRUE, scriptContext);
}
Var DataView::NewInstance(RecyclableObject* function, CallInfo callInfo, ...)
{
PROBE_STACK(function->GetScriptContext(), Js::Constants::MinStackDefault);
ARGUMENTS(args, callInfo);
ScriptContext* scriptContext = function->GetScriptContext();
AssertMsg(args.Info.Count > 0, "Should always have implicit 'this'");
Var newTarget = callInfo.Flags & CallFlags_NewTarget ? args.Values[args.Info.Count] : args[0];
bool isCtorSuperCall = (callInfo.Flags & CallFlags_New) && newTarget != nullptr && RecyclableObject::Is(newTarget);
Assert(isCtorSuperCall || !(callInfo.Flags & CallFlags_New) || args[0] == nullptr);
uint32 byteLength = 0;
uint32 mappedLength;
int32 offset = 0;
double numberOffset = 0;
ArrayBuffer* arrayBuffer = nullptr;
DataView* dataView;
//1. If NewTarget is undefined, throw a TypeError exception.
if (!(callInfo.Flags & CallFlags_New) || (newTarget && JavascriptOperators::IsUndefinedObject(newTarget)))
{
JavascriptError::ThrowTypeError(scriptContext, JSERR_ClassConstructorCannotBeCalledWithoutNew, L"DataView");
}
if (args.Info.Count < 2)
{
JavascriptError::ThrowTypeError(scriptContext, JSERR_DataView_NeedArgument, L"buffer");
}
// Currently the only reason we check for an external object is projection related, so it remains under conditional compilation.
RecyclableObject* jsArraySource = NULL;
if (JavascriptOperators::IsObject(args[1]) && JavascriptConversion::ToObject(args[1], scriptContext, &jsArraySource))
{
HRESULT hr = scriptContext->GetHostScriptContext()->ArrayBufferFromExternalObject(jsArraySource, &arrayBuffer);
switch (hr)
{
case S_OK:
case S_FALSE:
// Both of these cases will be handled by the arrayBuffer null check.
break;
default:
// Any FAILURE HRESULT or unexpected HRESULT.
JavascriptError::ThrowTypeError(scriptContext, JSERR_DataView_InvalidArugment, L"buffer");
break;
}
}
//2. If Type(buffer) is not Object, throw a TypeError exception.
//3. If buffer does not have an [[ArrayBufferData]] internal slot, throw a TypeError exception.
if (arrayBuffer == nullptr)
{
if (ArrayBuffer::Is(args[1]))
{
arrayBuffer = ArrayBuffer::FromVar(args[1]);
}
else
{
JavascriptError::ThrowTypeError(scriptContext, JSERR_DataView_NeedArgument, L"buffer");
}
}
//4. Let numberOffset be ToNumber(byteOffset).
//5. Let offset be ToInteger(numberOffset).
//6. ReturnIfAbrupt(offset).
//7. If numberOffset <> offset or offset < 0, throw a RangeError exception.
if (args.Info.Count > 2)
{
Var secondArgument = args[2];
numberOffset = JavascriptConversion::ToNumber(secondArgument, scriptContext);
offset = JavascriptConversion::ToInt32(numberOffset);
if (offset < 0 ||
numberOffset != offset)
{
JavascriptError::ThrowRangeError(
scriptContext, JSERR_DataView_InvalidArugment, L"byteOffset");
}
}
//8. If IsDetachedBuffer(buffer) is true, throw a TypeError exception.
if (arrayBuffer->IsDetached())
{
JavascriptError::ThrowTypeError(scriptContext, JSERR_This_NeedDataView);
}
//9. Let bufferByteLength be the value of buffer's[[ArrayBufferByteLength]] internal slot.
//10. If offset > bufferByteLength, throw a RangeError exception.
byteLength = arrayBuffer->GetByteLength();
if ((uint32)offset > byteLength)
{
JavascriptError::ThrowRangeError(
scriptContext, JSERR_DataView_InvalidArugment, L"byteOffset");
}
//11. If byteLength is undefined, then
// a. Let viewByteLength be bufferByteLength - offset.
//12. Else,
// a. Let viewByteLength be ToLength(byteLength).
// b. ReturnIfAbrupt(viewLength).
// c. If offset + viewByteLength > bufferByteLength, throw a RangeError exception.
if (args.Info.Count > 3 && !JavascriptOperators::IsUndefinedObject(args[3]))
{
Var thirdArgument = args[3];
mappedLength = (uint32)JavascriptConversion::ToLength(thirdArgument, scriptContext);
uint32 viewRange = mappedLength + offset;
if (viewRange > byteLength || viewRange < mappedLength) // overflow indicates out-of-range
{
JavascriptError::ThrowRangeError(
scriptContext, JSERR_DataView_InvalidArugment, L"byteLength");
}
}
else
{
mappedLength = byteLength - offset;
}
//13. Let O be OrdinaryCreateFromConstructor(NewTarget, "%DataViewPrototype%", [[DataView]], [[ViewedArrayBuffer]], [[ByteLength]], [[ByteOffset]]).
//14. ReturnIfAbrupt(O).
//15. Set O's[[DataView]] internal slot to true.
//16. Set O's[[ViewedArrayBuffer]] internal slot to buffer.
//17. Set O's[[ByteLength]] internal slot to viewByteLength.
//18. Set O's[[ByteOffset]] internal slot to offset.
//19. Return O.
dataView = scriptContext->GetLibrary()->CreateDataView(arrayBuffer, offset, mappedLength);
return isCtorSuperCall ?
JavascriptOperators::OrdinaryCreateFromConstructor(RecyclableObject::FromVar(newTarget), dataView, nullptr, scriptContext) :
dataView;
}
