gecko-dev/dom/canvas/ImageData.cpp

123 строки
3.4 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 et tw=78: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/dom/ImageData.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/HoldDropJSObjects.h"
#include "mozilla/dom/ImageDataBinding.h"
#include "jsapi.h"
namespace mozilla {
namespace dom {
NS_IMPL_CYCLE_COLLECTING_ADDREF(ImageData)
NS_IMPL_CYCLE_COLLECTING_RELEASE(ImageData)
NS_IMPL_CYCLE_COLLECTION_CLASS(ImageData)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ImageData)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(ImageData)
NS_IMPL_CYCLE_COLLECTION_TRACE_JS_MEMBER_CALLBACK(mData)
NS_IMPL_CYCLE_COLLECTION_TRACE_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(ImageData)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(ImageData)
tmp->DropData();
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
//static
already_AddRefed<ImageData>
ImageData::Constructor(const GlobalObject& aGlobal,
const uint32_t aWidth,
const uint32_t aHeight,
ErrorResult& aRv)
{
if (aWidth == 0 || aHeight == 0) {
aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
return nullptr;
}
CheckedInt<uint32_t> length = CheckedInt<uint32_t>(aWidth) * aHeight * 4;
if (!length.isValid()) {
aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
return nullptr;
}
js::AssertSameCompartment(aGlobal.Context(), aGlobal.Get());
JSObject* data = Uint8ClampedArray::Create(aGlobal.Context(),
length.value());
if (!data) {
aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
return nullptr;
}
RefPtr<ImageData> imageData = new ImageData(aWidth, aHeight, *data);
return imageData.forget();
}
//static
already_AddRefed<ImageData>
ImageData::Constructor(const GlobalObject& aGlobal,
const Uint8ClampedArray& aData,
const uint32_t aWidth,
const Optional<uint32_t>& aHeight,
ErrorResult& aRv)
{
aData.ComputeLengthAndData();
uint32_t length = aData.Length();
if (length == 0 || length % 4) {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
return nullptr;
}
length /= 4;
if (aWidth == 0) {
aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
return nullptr;
}
uint32_t height = length / aWidth;
if (length != aWidth * height ||
(aHeight.WasPassed() && aHeight.Value() != height)) {
aRv.Throw(NS_ERROR_DOM_INDEX_SIZE_ERR);
return nullptr;
}
if (JS_GetTypedArraySharedness(aData.Obj())) {
// Throw if the object is mapping shared memory (must opt in).
aRv.ThrowTypeError<MSG_TYPEDARRAY_IS_SHARED>(NS_LITERAL_STRING("Argument of ImageData constructor"));
return nullptr;
}
RefPtr<ImageData> imageData = new ImageData(aWidth, height, *aData.Obj());
return imageData.forget();
}
void
ImageData::HoldData()
{
mozilla::HoldJSObjects(this);
}
void
ImageData::DropData()
{
if (mData) {
mData = nullptr;
mozilla::DropJSObjects(this);
}
}
bool
ImageData::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto, JS::MutableHandle<JSObject*> aReflector)
{
return ImageData_Binding::Wrap(aCx, this, aGivenProto, aReflector);
}
} // namespace dom
} // namespace mozilla