gecko-dev/dom/html/HTMLCanvasElement.cpp
Emilio Cobos Álvarez 51758cfc9b Bug 1829189 - Make OnAttrSetButNotChanged and AfterSetAttr infallible. r=smaug
Same rg + sed shenanigans as the first patch.

There were two that could fail, both due to OOM:

 * HTMLInputElement::AfterSetAttr: If we fail (only in the type=range
   case) we end up with an old value without it being clamped by
   min/max/step.

 * HTMLBodyElement::AfterSetAttr: If we fail we won't peek up the
   DocShell's frame margins and styling could be incorrect.

That seems better than having to deal with broken states after we've
already set the attribute.

Depends on D176069

Differential Revision: https://phabricator.services.mozilla.com/D176070
2023-04-21 08:56:27 +00:00

1364 lines
43 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/HTMLCanvasElement.h"
#include "ImageEncoder.h"
#include "jsapi.h"
#include "jsfriendapi.h"
#include "MediaTrackGraph.h"
#include "mozilla/Assertions.h"
#include "mozilla/Base64.h"
#include "mozilla/BasePrincipal.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/PresShell.h"
#include "mozilla/dom/CanvasCaptureMediaStream.h"
#include "mozilla/dom/CanvasRenderingContext2D.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/GeneratePlaceholderCanvasData.h"
#include "mozilla/dom/Event.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/HTMLCanvasElementBinding.h"
#include "mozilla/dom/VideoStreamTrack.h"
#include "mozilla/dom/MouseEvent.h"
#include "mozilla/dom/OffscreenCanvas.h"
#include "mozilla/dom/OffscreenCanvasDisplayHelper.h"
#include "mozilla/EventDispatcher.h"
#include "mozilla/gfx/Rect.h"
#include "mozilla/layers/CanvasRenderer.h"
#include "mozilla/layers/WebRenderCanvasRenderer.h"
#include "mozilla/layers/WebRenderUserData.h"
#include "mozilla/MouseEvents.h"
#include "mozilla/Preferences.h"
#include "mozilla/ProfilerLabels.h"
#include "mozilla/Telemetry.h"
#include "mozilla/webgpu/CanvasContext.h"
#include "nsAttrValueInlines.h"
#include "nsContentUtils.h"
#include "nsDisplayList.h"
#include "nsDOMJSUtils.h"
#include "nsITimer.h"
#include "nsJSUtils.h"
#include "nsLayoutUtils.h"
#include "nsMathUtils.h"
#include "nsNetUtil.h"
#include "nsRefreshDriver.h"
#include "nsStreamUtils.h"
#include "ActiveLayerTracker.h"
#include "CanvasUtils.h"
#include "VRManagerChild.h"
#include "ClientWebGLContext.h"
#include "WindowRenderer.h"
using namespace mozilla::layers;
using namespace mozilla::gfx;
NS_IMPL_NS_NEW_HTML_ELEMENT(Canvas)
namespace mozilla::dom {
class RequestedFrameRefreshObserver : public nsARefreshObserver {
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(RequestedFrameRefreshObserver, override)
public:
RequestedFrameRefreshObserver(HTMLCanvasElement* const aOwningElement,
nsRefreshDriver* aRefreshDriver,
bool aReturnPlaceholderData)
: mRegistered(false),
mReturnPlaceholderData(aReturnPlaceholderData),
mOwningElement(aOwningElement),
mRefreshDriver(aRefreshDriver),
mWatchManager(this, AbstractThread::MainThread()),
mPendingThrottledCapture(false) {
MOZ_ASSERT(mOwningElement);
}
static already_AddRefed<DataSourceSurface> CopySurface(
const RefPtr<SourceSurface>& aSurface, bool aReturnPlaceholderData) {
RefPtr<DataSourceSurface> data = aSurface->GetDataSurface();
if (!data) {
return nullptr;
}
DataSourceSurface::ScopedMap read(data, DataSourceSurface::READ);
if (!read.IsMapped()) {
return nullptr;
}
RefPtr<DataSourceSurface> copy = Factory::CreateDataSourceSurfaceWithStride(
data->GetSize(), data->GetFormat(), read.GetStride());
if (!copy) {
return nullptr;
}
DataSourceSurface::ScopedMap write(copy, DataSourceSurface::WRITE);
if (!write.IsMapped()) {
return nullptr;
}
MOZ_ASSERT(read.GetStride() == write.GetStride());
MOZ_ASSERT(data->GetSize() == copy->GetSize());
MOZ_ASSERT(data->GetFormat() == copy->GetFormat());
if (aReturnPlaceholderData) {
auto size = write.GetStride() * copy->GetSize().height;
auto* data = write.GetData();
GeneratePlaceholderCanvasData(size, data);
} else {
memcpy(write.GetData(), read.GetData(),
write.GetStride() * copy->GetSize().height);
}
return copy.forget();
}
void SetReturnPlaceholderData(bool aReturnPlaceholderData) {
mReturnPlaceholderData = aReturnPlaceholderData;
}
void NotifyCaptureStateChange() {
if (mPendingThrottledCapture) {
return;
}
if (!mOwningElement) {
return;
}
Watchable<FrameCaptureState>* captureState =
mOwningElement->GetFrameCaptureState();
if (!captureState) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: No capture state"_ns);
return;
}
if (captureState->Ref() == FrameCaptureState::CLEAN) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: CLEAN"_ns);
return;
}
if (!mRefreshDriver) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: no refresh driver"_ns);
return;
}
if (!mRefreshDriver->IsThrottled()) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: not throttled"_ns);
return;
}
TimeStamp now = TimeStamp::Now();
TimeStamp next =
mLastCaptureTime.IsNull()
? now
: mLastCaptureTime + TimeDuration::FromMilliseconds(
nsRefreshDriver::DefaultInterval());
if (mLastCaptureTime.IsNull() || next <= now) {
AUTO_PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"CaptureFrame direct while throttled"_ns);
CaptureFrame(now);
return;
}
nsCString str;
if (profiler_thread_is_being_profiled_for_markers()) {
str.AppendPrintf("Delaying CaptureFrame by %.2fms",
(next - now).ToMilliseconds());
}
AUTO_PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {}, str);
mPendingThrottledCapture = true;
AbstractThread::MainThread()->DelayedDispatch(
NS_NewRunnableFunction(
__func__,
[this, self = RefPtr<RequestedFrameRefreshObserver>(this), next] {
mPendingThrottledCapture = false;
AUTO_PROFILER_MARKER_TEXT(
"Canvas CaptureStream", MEDIA_RT, {},
"CaptureFrame after delay while throttled"_ns);
CaptureFrame(next);
}),
// next >= now, so this is a guard for (next - now) flooring to 0.
std::max<uint32_t>(
1, static_cast<uint32_t>((next - now).ToMilliseconds())));
}
void WillRefresh(TimeStamp aTime) override {
AUTO_PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"CaptureFrame by refresh driver"_ns);
CaptureFrame(aTime);
}
void CaptureFrame(TimeStamp aTime) {
MOZ_ASSERT(NS_IsMainThread());
if (!mOwningElement) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: no owning element"_ns);
return;
}
if (mOwningElement->IsWriteOnly()) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: write only"_ns);
return;
}
if (auto* captureStateWatchable = mOwningElement->GetFrameCaptureState();
captureStateWatchable &&
*captureStateWatchable == FrameCaptureState::CLEAN) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: CLEAN"_ns);
return;
}
// Mark the context already now, since if the frame capture state is DIRTY
// and we catch an early return below (not marking it CLEAN), the next draw
// will not trigger a capture state change from the
// Watchable<FrameCaptureState>.
mOwningElement->MarkContextCleanForFrameCapture();
mOwningElement->ProcessDestroyedFrameListeners();
if (!mOwningElement->IsFrameCaptureRequested(aTime)) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: no capture requested"_ns);
return;
}
RefPtr<SourceSurface> snapshot;
{
AUTO_PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"GetSnapshot"_ns);
snapshot = mOwningElement->GetSurfaceSnapshot(nullptr);
if (!snapshot) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: snapshot failed"_ns);
return;
}
}
RefPtr<DataSourceSurface> copy;
{
AUTO_PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"CopySurface"_ns);
copy = CopySurface(snapshot, mReturnPlaceholderData);
if (!copy) {
PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {},
"Abort: copy failed"_ns);
return;
}
}
nsCString str;
if (profiler_thread_is_being_profiled_for_markers()) {
TimeDuration sinceLast =
aTime - (mLastCaptureTime.IsNull() ? aTime : mLastCaptureTime);
str.AppendPrintf("Forwarding captured frame %.2fms after last",
sinceLast.ToMilliseconds());
}
AUTO_PROFILER_MARKER_TEXT("Canvas CaptureStream", MEDIA_RT, {}, str);
if (!mLastCaptureTime.IsNull() && aTime <= mLastCaptureTime) {
aTime = mLastCaptureTime + TimeDuration::FromMilliseconds(1);
}
mLastCaptureTime = aTime;
mOwningElement->SetFrameCapture(copy.forget(), aTime);
}
void DetachFromRefreshDriver() {
MOZ_ASSERT(mOwningElement);
MOZ_ASSERT(mRefreshDriver);
Unregister();
mRefreshDriver = nullptr;
mWatchManager.Shutdown();
}
void Register() {
if (mRegistered) {
return;
}
MOZ_ASSERT(mRefreshDriver);
if (mRefreshDriver) {
mRefreshDriver->AddRefreshObserver(this, FlushType::Display,
"Canvas frame capture listeners");
mRegistered = true;
}
if (!mOwningElement) {
return;
}
if (Watchable<FrameCaptureState>* captureState =
mOwningElement->GetFrameCaptureState()) {
mWatchManager.Watch(
*captureState,
&RequestedFrameRefreshObserver::NotifyCaptureStateChange);
}
}
void Unregister() {
if (!mRegistered) {
return;
}
MOZ_ASSERT(mRefreshDriver);
if (mRefreshDriver) {
mRefreshDriver->RemoveRefreshObserver(this, FlushType::Display);
mRegistered = false;
}
if (!mOwningElement) {
return;
}
if (Watchable<FrameCaptureState>* captureState =
mOwningElement->GetFrameCaptureState()) {
mWatchManager.Unwatch(
*captureState,
&RequestedFrameRefreshObserver::NotifyCaptureStateChange);
}
}
private:
virtual ~RequestedFrameRefreshObserver() {
MOZ_ASSERT(!mRefreshDriver);
MOZ_ASSERT(!mRegistered);
}
bool mRegistered;
bool mReturnPlaceholderData;
const WeakPtr<HTMLCanvasElement> mOwningElement;
RefPtr<nsRefreshDriver> mRefreshDriver;
WatchManager<RequestedFrameRefreshObserver> mWatchManager;
TimeStamp mLastCaptureTime;
bool mPendingThrottledCapture;
};
// ---------------------------------------------------------------------------
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(HTMLCanvasPrintState, mCanvas, mContext,
mCallback)
HTMLCanvasPrintState::HTMLCanvasPrintState(
HTMLCanvasElement* aCanvas, nsICanvasRenderingContextInternal* aContext,
nsITimerCallback* aCallback)
: mIsDone(false),
mPendingNotify(false),
mCanvas(aCanvas),
mContext(aContext),
mCallback(aCallback) {}
HTMLCanvasPrintState::~HTMLCanvasPrintState() = default;
/* virtual */
JSObject* HTMLCanvasPrintState::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return MozCanvasPrintState_Binding::Wrap(aCx, this, aGivenProto);
}
nsISupports* HTMLCanvasPrintState::Context() const { return mContext; }
void HTMLCanvasPrintState::Done() {
if (!mPendingNotify && !mIsDone) {
// The canvas needs to be invalidated for printing reftests on linux to
// work.
if (mCanvas) {
mCanvas->InvalidateCanvas();
}
RefPtr<nsRunnableMethod<HTMLCanvasPrintState>> doneEvent =
NewRunnableMethod("dom::HTMLCanvasPrintState::NotifyDone", this,
&HTMLCanvasPrintState::NotifyDone);
if (NS_SUCCEEDED(NS_DispatchToCurrentThread(doneEvent))) {
mPendingNotify = true;
}
}
}
void HTMLCanvasPrintState::NotifyDone() {
mIsDone = true;
mPendingNotify = false;
if (mCallback) {
mCallback->Notify(nullptr);
}
}
// ---------------------------------------------------------------------------
HTMLCanvasElementObserver::HTMLCanvasElementObserver(
HTMLCanvasElement* aElement)
: mElement(aElement) {
RegisterObserverEvents();
}
HTMLCanvasElementObserver::~HTMLCanvasElementObserver() { Destroy(); }
void HTMLCanvasElementObserver::Destroy() {
UnregisterObserverEvents();
mElement = nullptr;
}
void HTMLCanvasElementObserver::RegisterObserverEvents() {
if (!mElement) {
return;
}
nsCOMPtr<nsIObserverService> observerService =
mozilla::services::GetObserverService();
MOZ_ASSERT(observerService);
if (observerService) {
observerService->AddObserver(this, "memory-pressure", false);
observerService->AddObserver(this, "canvas-device-reset", false);
}
}
void HTMLCanvasElementObserver::UnregisterObserverEvents() {
if (!mElement) {
return;
}
nsCOMPtr<nsIObserverService> observerService =
mozilla::services::GetObserverService();
// Do not assert on observerService here. This might be triggered by
// the cycle collector at a late enough time, that XPCOM services are
// no longer available. See bug 1029504.
if (observerService) {
observerService->RemoveObserver(this, "memory-pressure");
observerService->RemoveObserver(this, "canvas-device-reset");
}
}
NS_IMETHODIMP
HTMLCanvasElementObserver::Observe(nsISupports*, const char* aTopic,
const char16_t*) {
if (!mElement) {
return NS_OK;
}
if (strcmp(aTopic, "memory-pressure") == 0) {
mElement->OnMemoryPressure();
} else if (strcmp(aTopic, "canvas-device-reset") == 0) {
mElement->OnDeviceReset();
}
return NS_OK;
}
NS_IMPL_ISUPPORTS(HTMLCanvasElementObserver, nsIObserver)
// ---------------------------------------------------------------------------
HTMLCanvasElement::HTMLCanvasElement(
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
: nsGenericHTMLElement(std::move(aNodeInfo)),
mResetLayer(true),
mMaybeModified(false),
mWriteOnly(false) {}
HTMLCanvasElement::~HTMLCanvasElement() { Destroy(); }
void HTMLCanvasElement::Destroy() {
if (mOffscreenDisplay) {
mOffscreenDisplay->Destroy();
mOffscreenDisplay = nullptr;
mImageContainer = nullptr;
}
if (mContextObserver) {
mContextObserver->Destroy();
mContextObserver = nullptr;
}
ResetPrintCallback();
if (mRequestedFrameRefreshObserver) {
mRequestedFrameRefreshObserver->DetachFromRefreshDriver();
mRequestedFrameRefreshObserver = nullptr;
}
}
NS_IMPL_CYCLE_COLLECTION_CLASS(HTMLCanvasElement)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(HTMLCanvasElement,
nsGenericHTMLElement)
tmp->Destroy();
NS_IMPL_CYCLE_COLLECTION_UNLINK(mCurrentContext, mPrintCallback, mPrintState,
mOriginalCanvas, mOffscreenCanvas)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(HTMLCanvasElement,
nsGenericHTMLElement)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mCurrentContext, mPrintCallback,
mPrintState, mOriginalCanvas,
mOffscreenCanvas)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(HTMLCanvasElement,
nsGenericHTMLElement)
NS_IMPL_ELEMENT_CLONE(HTMLCanvasElement)
/* virtual */
JSObject* HTMLCanvasElement::WrapNode(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return HTMLCanvasElement_Binding::Wrap(aCx, this, aGivenProto);
}
already_AddRefed<nsICanvasRenderingContextInternal>
HTMLCanvasElement::CreateContext(CanvasContextType aContextType) {
// Note that the compositor backend will be LAYERS_NONE if there is no widget.
RefPtr<nsICanvasRenderingContextInternal> ret =
CreateContextHelper(aContextType, GetCompositorBackendType());
// Add Observer for webgl canvas.
if (aContextType == CanvasContextType::WebGL1 ||
aContextType == CanvasContextType::WebGL2 ||
aContextType == CanvasContextType::Canvas2D) {
if (!mContextObserver) {
mContextObserver = new HTMLCanvasElementObserver(this);
}
}
ret->SetCanvasElement(this);
return ret.forget();
}
nsIntSize HTMLCanvasElement::GetWidthHeight() {
nsIntSize size(DEFAULT_CANVAS_WIDTH, DEFAULT_CANVAS_HEIGHT);
const nsAttrValue* value;
if ((value = GetParsedAttr(nsGkAtoms::width)) &&
value->Type() == nsAttrValue::eInteger) {
size.width = value->GetIntegerValue();
}
if ((value = GetParsedAttr(nsGkAtoms::height)) &&
value->Type() == nsAttrValue::eInteger) {
size.height = value->GetIntegerValue();
}
MOZ_ASSERT(size.width >= 0 && size.height >= 0,
"we should've required <canvas> width/height attrs to be "
"unsigned (non-negative) values");
return size;
}
void HTMLCanvasElement::AfterSetAttr(int32_t aNamespaceID, nsAtom* aName,
const nsAttrValue* aValue,
const nsAttrValue* aOldValue,
nsIPrincipal* aSubjectPrincipal,
bool aNotify) {
AfterMaybeChangeAttr(aNamespaceID, aName, aNotify);
return nsGenericHTMLElement::AfterSetAttr(
aNamespaceID, aName, aValue, aOldValue, aSubjectPrincipal, aNotify);
}
void HTMLCanvasElement::OnAttrSetButNotChanged(
int32_t aNamespaceID, nsAtom* aName, const nsAttrValueOrString& aValue,
bool aNotify) {
AfterMaybeChangeAttr(aNamespaceID, aName, aNotify);
return nsGenericHTMLElement::OnAttrSetButNotChanged(aNamespaceID, aName,
aValue, aNotify);
}
void HTMLCanvasElement::AfterMaybeChangeAttr(int32_t aNamespaceID,
nsAtom* aName, bool aNotify) {
if (mCurrentContext && aNamespaceID == kNameSpaceID_None &&
(aName == nsGkAtoms::width || aName == nsGkAtoms::height ||
aName == nsGkAtoms::moz_opaque)) {
ErrorResult dummy;
UpdateContext(nullptr, JS::NullHandleValue, dummy);
}
}
void HTMLCanvasElement::HandlePrintCallback(nsPresContext* aPresContext) {
// Only call the print callback here if 1) we're in a print testing mode or
// print preview mode, 2) the canvas has a print callback and 3) the callback
// hasn't already been called. For real printing the callback is handled in
// nsPageSequenceFrame::PrePrintNextSheet.
if ((aPresContext->Type() == nsPresContext::eContext_PageLayout ||
aPresContext->Type() == nsPresContext::eContext_PrintPreview) &&
!mPrintState && GetMozPrintCallback()) {
DispatchPrintCallback(nullptr);
}
}
nsresult HTMLCanvasElement::DispatchPrintCallback(nsITimerCallback* aCallback) {
// For print reftests the context may not be initialized yet, so get a context
// so mCurrentContext is set.
if (!mCurrentContext) {
nsresult rv;
nsCOMPtr<nsISupports> context;
rv = GetContext(u"2d"_ns, getter_AddRefs(context));
NS_ENSURE_SUCCESS(rv, rv);
}
mPrintState = new HTMLCanvasPrintState(this, mCurrentContext, aCallback);
RefPtr<nsRunnableMethod<HTMLCanvasElement>> renderEvent =
NewRunnableMethod("dom::HTMLCanvasElement::CallPrintCallback", this,
&HTMLCanvasElement::CallPrintCallback);
return OwnerDoc()->Dispatch(TaskCategory::Other, renderEvent.forget());
}
void HTMLCanvasElement::CallPrintCallback() {
if (!mPrintState) {
// `mPrintState` might have been destroyed by cancelling the previous
// printing (especially the canvas frame destruction) during processing
// event loops in the printing.
return;
}
RefPtr<PrintCallback> callback = GetMozPrintCallback();
RefPtr<HTMLCanvasPrintState> state = mPrintState;
callback->Call(*state);
}
void HTMLCanvasElement::ResetPrintCallback() {
if (mPrintState) {
mPrintState = nullptr;
}
}
bool HTMLCanvasElement::IsPrintCallbackDone() {
if (mPrintState == nullptr) {
return true;
}
return mPrintState->mIsDone;
}
HTMLCanvasElement* HTMLCanvasElement::GetOriginalCanvas() {
return mOriginalCanvas ? mOriginalCanvas.get() : this;
}
nsresult HTMLCanvasElement::CopyInnerTo(HTMLCanvasElement* aDest) {
nsresult rv = nsGenericHTMLElement::CopyInnerTo(aDest);
NS_ENSURE_SUCCESS(rv, rv);
Document* destDoc = aDest->OwnerDoc();
if (destDoc->IsStaticDocument()) {
// The Firefox print preview code can create a static clone from an
// existing static clone, so we may not be the original 'canvas' element.
aDest->mOriginalCanvas = GetOriginalCanvas();
if (GetMozPrintCallback()) {
destDoc->SetHasPrintCallbacks();
}
// We make sure that the canvas is not zero sized since that would cause
// the DrawImage call below to return an error, which would cause printing
// to fail.
nsIntSize size = GetWidthHeight();
if (size.height > 0 && size.width > 0) {
nsCOMPtr<nsISupports> cxt;
aDest->GetContext(u"2d"_ns, getter_AddRefs(cxt));
RefPtr<CanvasRenderingContext2D> context2d =
static_cast<CanvasRenderingContext2D*>(cxt.get());
if (context2d && !mPrintCallback) {
CanvasImageSource source;
source.SetAsHTMLCanvasElement() = this;
ErrorResult err;
context2d->DrawImage(source, 0.0, 0.0, err);
rv = err.StealNSResult();
}
}
}
return rv;
}
nsChangeHint HTMLCanvasElement::GetAttributeChangeHint(const nsAtom* aAttribute,
int32_t aModType) const {
nsChangeHint retval =
nsGenericHTMLElement::GetAttributeChangeHint(aAttribute, aModType);
if (aAttribute == nsGkAtoms::width || aAttribute == nsGkAtoms::height) {
retval |= NS_STYLE_HINT_REFLOW;
} else if (aAttribute == nsGkAtoms::moz_opaque) {
retval |= NS_STYLE_HINT_VISUAL;
}
return retval;
}
void HTMLCanvasElement::MapAttributesIntoRule(
const nsMappedAttributes* aAttributes, MappedDeclarations& aDecls) {
MapAspectRatioInto(aAttributes, aDecls);
MapCommonAttributesInto(aAttributes, aDecls);
}
nsMapRuleToAttributesFunc HTMLCanvasElement::GetAttributeMappingFunction()
const {
return &MapAttributesIntoRule;
}
NS_IMETHODIMP_(bool)
HTMLCanvasElement::IsAttributeMapped(const nsAtom* aAttribute) const {
static const MappedAttributeEntry attributes[] = {
{nsGkAtoms::width}, {nsGkAtoms::height}, {nullptr}};
static const MappedAttributeEntry* const map[] = {attributes,
sCommonAttributeMap};
return FindAttributeDependence(aAttribute, map);
}
bool HTMLCanvasElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
const nsAString& aValue,
nsIPrincipal* aMaybeScriptedPrincipal,
nsAttrValue& aResult) {
if (aNamespaceID == kNameSpaceID_None &&
(aAttribute == nsGkAtoms::width || aAttribute == nsGkAtoms::height)) {
return aResult.ParseNonNegativeIntValue(aValue);
}
return nsGenericHTMLElement::ParseAttribute(aNamespaceID, aAttribute, aValue,
aMaybeScriptedPrincipal, aResult);
}
void HTMLCanvasElement::ToDataURL(JSContext* aCx, const nsAString& aType,
JS::Handle<JS::Value> aParams,
nsAString& aDataURL,
nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv) {
// mWriteOnly check is redundant, but optimizes for the common case.
if (mWriteOnly && !CallerCanRead(aCx)) {
aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
return;
}
nsresult rv = ToDataURLImpl(aCx, aSubjectPrincipal, aType, aParams, aDataURL);
if (NS_FAILED(rv)) {
aDataURL.AssignLiteral("data:,");
}
}
void HTMLCanvasElement::SetMozPrintCallback(PrintCallback* aCallback) {
mPrintCallback = aCallback;
}
PrintCallback* HTMLCanvasElement::GetMozPrintCallback() const {
if (mOriginalCanvas) {
return mOriginalCanvas->GetMozPrintCallback();
}
return mPrintCallback;
}
static uint32_t sCaptureSourceId = 0;
class CanvasCaptureTrackSource : public MediaStreamTrackSource {
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(CanvasCaptureTrackSource,
MediaStreamTrackSource)
CanvasCaptureTrackSource(nsIPrincipal* aPrincipal,
CanvasCaptureMediaStream* aCaptureStream)
: MediaStreamTrackSource(
aPrincipal, nsString(),
TrackingId(TrackingId::Source::Canvas, sCaptureSourceId++,
TrackingId::TrackAcrossProcesses::Yes)),
mCaptureStream(aCaptureStream) {}
MediaSourceEnum GetMediaSource() const override {
return MediaSourceEnum::Other;
}
bool HasAlpha() const override {
if (!mCaptureStream || !mCaptureStream->Canvas()) {
// In cycle-collection
return false;
}
return !mCaptureStream->Canvas()->GetIsOpaque();
}
void Stop() override {
if (!mCaptureStream) {
NS_ERROR("No stream");
return;
}
mCaptureStream->StopCapture();
}
void Disable() override {}
void Enable() override {}
private:
virtual ~CanvasCaptureTrackSource() = default;
RefPtr<CanvasCaptureMediaStream> mCaptureStream;
};
NS_IMPL_ADDREF_INHERITED(CanvasCaptureTrackSource, MediaStreamTrackSource)
NS_IMPL_RELEASE_INHERITED(CanvasCaptureTrackSource, MediaStreamTrackSource)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(CanvasCaptureTrackSource)
NS_INTERFACE_MAP_END_INHERITING(MediaStreamTrackSource)
NS_IMPL_CYCLE_COLLECTION_INHERITED(CanvasCaptureTrackSource,
MediaStreamTrackSource, mCaptureStream)
already_AddRefed<CanvasCaptureMediaStream> HTMLCanvasElement::CaptureStream(
const Optional<double>& aFrameRate, nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv) {
if (IsWriteOnly()) {
aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
return nullptr;
}
nsPIDOMWindowInner* window = OwnerDoc()->GetInnerWindow();
if (!window) {
aRv.Throw(NS_ERROR_FAILURE);
return nullptr;
}
if (!mCurrentContext) {
aRv.Throw(NS_ERROR_NOT_INITIALIZED);
return nullptr;
}
auto stream = MakeRefPtr<CanvasCaptureMediaStream>(window, this);
nsCOMPtr<nsIPrincipal> principal = NodePrincipal();
nsresult rv = stream->Init(aFrameRate, principal);
if (NS_FAILED(rv)) {
aRv.Throw(rv);
return nullptr;
}
RefPtr<MediaStreamTrack> track =
new VideoStreamTrack(window, stream->GetSourceStream(),
new CanvasCaptureTrackSource(principal, stream));
stream->AddTrackInternal(track);
// Check site-specific permission and display prompt if appropriate.
// If no permission, arrange for the frame capture listener to return
// all-white, opaque image data.
bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(
OwnerDoc(), nsContentUtils::GetCurrentJSContext(),
Some(&aSubjectPrincipal));
rv = RegisterFrameCaptureListener(stream->FrameCaptureListener(),
usePlaceholder);
if (NS_FAILED(rv)) {
aRv.Throw(rv);
return nullptr;
}
return stream.forget();
}
nsresult HTMLCanvasElement::ExtractData(JSContext* aCx,
nsIPrincipal& aSubjectPrincipal,
nsAString& aType,
const nsAString& aOptions,
nsIInputStream** aStream) {
// Check site-specific permission and display prompt if appropriate.
// If no permission, return all-white, opaque image data.
bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(
OwnerDoc(), aCx, Some(&aSubjectPrincipal));
return ImageEncoder::ExtractData(aType, aOptions, GetSize(), usePlaceholder,
mCurrentContext, mCanvasRenderer, aStream);
}
nsresult HTMLCanvasElement::ToDataURLImpl(JSContext* aCx,
nsIPrincipal& aSubjectPrincipal,
const nsAString& aMimeType,
const JS::Value& aEncoderOptions,
nsAString& aDataURL) {
nsIntSize size = GetWidthHeight();
if (size.height == 0 || size.width == 0) {
aDataURL = u"data:,"_ns;
return NS_OK;
}
nsAutoString type;
nsContentUtils::ASCIIToLower(aMimeType, type);
nsAutoString params;
bool usingCustomParseOptions;
nsresult rv =
ParseParams(aCx, type, aEncoderOptions, params, &usingCustomParseOptions);
if (NS_FAILED(rv)) {
return rv;
}
nsCOMPtr<nsIInputStream> stream;
rv =
ExtractData(aCx, aSubjectPrincipal, type, params, getter_AddRefs(stream));
// If there are unrecognized custom parse options, we should fall back to
// the default values for the encoder without any options at all.
if (rv == NS_ERROR_INVALID_ARG && usingCustomParseOptions) {
rv = ExtractData(aCx, aSubjectPrincipal, type, u""_ns,
getter_AddRefs(stream));
}
NS_ENSURE_SUCCESS(rv, rv);
// build data URL string
aDataURL = u"data:"_ns + type + u";base64,"_ns;
uint64_t count;
rv = stream->Available(&count);
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_TRUE(count <= UINT32_MAX, NS_ERROR_FILE_TOO_BIG);
return Base64EncodeInputStream(stream, aDataURL, (uint32_t)count,
aDataURL.Length());
}
void HTMLCanvasElement::ToBlob(JSContext* aCx, BlobCallback& aCallback,
const nsAString& aType,
JS::Handle<JS::Value> aParams,
nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv) {
// mWriteOnly check is redundant, but optimizes for the common case.
if (mWriteOnly && !CallerCanRead(aCx)) {
aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
return;
}
nsCOMPtr<nsIGlobalObject> global = OwnerDoc()->GetScopeObject();
MOZ_ASSERT(global);
nsIntSize elemSize = GetWidthHeight();
if (elemSize.width == 0 || elemSize.height == 0) {
// According to spec, blob should return null if either its horizontal
// dimension or its vertical dimension is zero. See link below.
// https://html.spec.whatwg.org/multipage/scripting.html#dom-canvas-toblob
OwnerDoc()->Dispatch(
TaskCategory::Other,
NewRunnableMethod<Blob*, const char*>(
"dom::HTMLCanvasElement::ToBlob", &aCallback,
static_cast<void (BlobCallback::*)(Blob*, const char*)>(
&BlobCallback::Call),
nullptr, nullptr));
return;
}
// Check site-specific permission and display prompt if appropriate.
// If no permission, return all-white, opaque image data.
bool usePlaceholder = !CanvasUtils::IsImageExtractionAllowed(
OwnerDoc(), aCx, Some(&aSubjectPrincipal));
CanvasRenderingContextHelper::ToBlob(aCx, global, aCallback, aType, aParams,
usePlaceholder, aRv);
}
OffscreenCanvas* HTMLCanvasElement::TransferControlToOffscreen(
ErrorResult& aRv) {
if (mCurrentContext || mOffscreenCanvas) {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
return nullptr;
}
MOZ_ASSERT(!mOffscreenDisplay);
nsPIDOMWindowInner* win = OwnerDoc()->GetInnerWindow();
if (!win) {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
return nullptr;
}
LayersBackend backend = LayersBackend::LAYERS_NONE;
TextureType textureType = TextureType::Unknown;
nsIWidget* docWidget = nsContentUtils::WidgetForDocument(OwnerDoc());
if (docWidget) {
WindowRenderer* renderer = docWidget->GetWindowRenderer();
if (renderer) {
backend = renderer->GetCompositorBackendType();
textureType = TexTypeForWebgl(renderer->AsKnowsCompositor());
}
}
nsIntSize sz = GetWidthHeight();
mOffscreenDisplay =
MakeRefPtr<OffscreenCanvasDisplayHelper>(this, sz.width, sz.height);
mOffscreenCanvas =
new OffscreenCanvas(win->AsGlobal(), sz.width, sz.height, backend,
textureType, mOffscreenDisplay);
if (mWriteOnly) {
mOffscreenCanvas->SetWriteOnly();
}
if (!mContextObserver) {
mContextObserver = new HTMLCanvasElementObserver(this);
}
return mOffscreenCanvas;
}
nsresult HTMLCanvasElement::GetContext(const nsAString& aContextId,
nsISupports** aContext) {
ErrorResult rv;
mMaybeModified = true; // For FirstContentfulPaint
*aContext = GetContext(nullptr, aContextId, JS::NullHandleValue, rv).take();
return rv.StealNSResult();
}
already_AddRefed<nsISupports> HTMLCanvasElement::GetContext(
JSContext* aCx, const nsAString& aContextId,
JS::Handle<JS::Value> aContextOptions, ErrorResult& aRv) {
if (mOffscreenCanvas) {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
return nullptr;
}
mMaybeModified = true; // For FirstContentfulPaint
return CanvasRenderingContextHelper::GetOrCreateContext(
aCx, aContextId,
aContextOptions.isObject() ? aContextOptions : JS::NullHandleValue, aRv);
}
nsIntSize HTMLCanvasElement::GetSize() { return GetWidthHeight(); }
bool HTMLCanvasElement::IsWriteOnly() const { return mWriteOnly; }
void HTMLCanvasElement::SetWriteOnly(
nsIPrincipal* aExpandedReader /* = nullptr */) {
mExpandedReader = aExpandedReader;
mWriteOnly = true;
if (mOffscreenCanvas) {
mOffscreenCanvas->SetWriteOnly();
}
}
bool HTMLCanvasElement::CallerCanRead(JSContext* aCx) const {
if (!mWriteOnly) {
return true;
}
nsIPrincipal* prin = nsContentUtils::SubjectPrincipal(aCx);
// If mExpandedReader is set, this canvas was tainted only by
// mExpandedReader's resources. So allow reading if the subject
// principal subsumes mExpandedReader.
if (mExpandedReader && prin->Subsumes(mExpandedReader)) {
return true;
}
return nsContentUtils::PrincipalHasPermission(*prin,
nsGkAtoms::all_urlsPermission);
}
void HTMLCanvasElement::SetWidth(uint32_t aWidth, ErrorResult& aRv) {
if (mOffscreenCanvas) {
aRv.ThrowInvalidStateError(
"Cannot set width of placeholder canvas transferred to "
"OffscreenCanvas.");
return;
}
SetUnsignedIntAttr(nsGkAtoms::width, aWidth, DEFAULT_CANVAS_WIDTH, aRv);
}
void HTMLCanvasElement::SetHeight(uint32_t aHeight, ErrorResult& aRv) {
if (mOffscreenCanvas) {
aRv.ThrowInvalidStateError(
"Cannot set height of placeholder canvas transferred to "
"OffscreenCanvas.");
return;
}
SetUnsignedIntAttr(nsGkAtoms::height, aHeight, DEFAULT_CANVAS_HEIGHT, aRv);
}
void HTMLCanvasElement::InvalidateCanvasPlaceholder(uint32_t aWidth,
uint32_t aHeight) {
ErrorResult rv;
SetUnsignedIntAttr(nsGkAtoms::width, aWidth, DEFAULT_CANVAS_WIDTH, rv);
MOZ_ASSERT(!rv.Failed());
SetUnsignedIntAttr(nsGkAtoms::height, aHeight, DEFAULT_CANVAS_HEIGHT, rv);
MOZ_ASSERT(!rv.Failed());
}
void HTMLCanvasElement::InvalidateCanvasContent(const gfx::Rect* damageRect) {
// Cache the current ImageContainer to avoid contention on the mutex.
if (mOffscreenDisplay) {
mImageContainer = mOffscreenDisplay->GetImageContainer();
}
// We don't need to flush anything here; if there's no frame or if
// we plan to reframe we don't need to invalidate it anyway.
nsIFrame* frame = GetPrimaryFrame();
if (!frame) return;
// When using layers-free WebRender, we cannot invalidate the layer (because
// there isn't one). Instead, we mark the CanvasRenderer dirty and scheduling
// an empty transaction which is effectively equivalent.
CanvasRenderer* renderer = nullptr;
const auto key = static_cast<uint32_t>(DisplayItemType::TYPE_CANVAS);
RefPtr<WebRenderCanvasData> data =
GetWebRenderUserData<WebRenderCanvasData>(frame, key);
if (data) {
renderer = data->GetCanvasRenderer();
}
if (renderer) {
renderer->SetDirty();
frame->SchedulePaint(nsIFrame::PAINT_COMPOSITE_ONLY);
} else {
if (damageRect) {
nsIntSize size = GetWidthHeight();
if (size.width != 0 && size.height != 0) {
gfx::IntRect invalRect = gfx::IntRect::Truncate(*damageRect);
frame->InvalidateLayer(DisplayItemType::TYPE_CANVAS, &invalRect);
}
} else {
frame->InvalidateLayer(DisplayItemType::TYPE_CANVAS);
}
// This path is taken in two situations:
// 1) WebRender is enabled and has not yet processed a display list.
// 2) WebRender is disabled and layer invalidation failed.
// In both cases, schedule a full paint to properly update canvas.
frame->SchedulePaint(nsIFrame::PAINT_DEFAULT, false);
}
/*
* Treat canvas invalidations as animation activity for JS. Frequently
* invalidating a canvas will feed into heuristics and cause JIT code to be
* kept around longer, for smoother animations.
*/
nsPIDOMWindowInner* win = OwnerDoc()->GetInnerWindow();
if (win) {
if (JSObject* obj = win->AsGlobal()->GetGlobalJSObject()) {
js::NotifyAnimationActivity(obj);
}
}
}
void HTMLCanvasElement::InvalidateCanvas() {
// We don't need to flush anything here; if there's no frame or if
// we plan to reframe we don't need to invalidate it anyway.
nsIFrame* frame = GetPrimaryFrame();
if (!frame) return;
frame->InvalidateFrame();
}
bool HTMLCanvasElement::GetIsOpaque() {
if (mCurrentContext) {
return mCurrentContext->GetIsOpaque();
}
return GetOpaqueAttr();
}
bool HTMLCanvasElement::GetOpaqueAttr() {
return HasAttr(kNameSpaceID_None, nsGkAtoms::moz_opaque);
}
CanvasContextType HTMLCanvasElement::GetCurrentContextType() {
if (mCurrentContextType == CanvasContextType::NoContext &&
mOffscreenDisplay) {
mCurrentContextType = mOffscreenDisplay->GetContextType();
}
return mCurrentContextType;
}
already_AddRefed<Image> HTMLCanvasElement::GetAsImage() {
if (mOffscreenDisplay) {
return mOffscreenDisplay->GetAsImage();
}
if (mCurrentContext) {
return mCurrentContext->GetAsImage();
}
return nullptr;
}
bool HTMLCanvasElement::UpdateWebRenderCanvasData(
nsDisplayListBuilder* aBuilder, WebRenderCanvasData* aCanvasData) {
MOZ_ASSERT(!mOffscreenDisplay);
if (mCurrentContext) {
return mCurrentContext->UpdateWebRenderCanvasData(aBuilder, aCanvasData);
}
// Clear CanvasRenderer of WebRenderCanvasData
aCanvasData->ClearCanvasRenderer();
return false;
}
bool HTMLCanvasElement::InitializeCanvasRenderer(nsDisplayListBuilder* aBuilder,
CanvasRenderer* aRenderer) {
MOZ_ASSERT(!mOffscreenDisplay);
if (mCurrentContext) {
return mCurrentContext->InitializeCanvasRenderer(aBuilder, aRenderer);
}
return false;
}
void HTMLCanvasElement::MarkContextClean() {
if (!mCurrentContext) return;
mCurrentContext->MarkContextClean();
}
void HTMLCanvasElement::MarkContextCleanForFrameCapture() {
if (!mCurrentContext) return;
mCurrentContext->MarkContextCleanForFrameCapture();
}
Watchable<FrameCaptureState>* HTMLCanvasElement::GetFrameCaptureState() {
if (!mCurrentContext) {
return nullptr;
}
return mCurrentContext->GetFrameCaptureState();
}
nsresult HTMLCanvasElement::RegisterFrameCaptureListener(
FrameCaptureListener* aListener, bool aReturnPlaceholderData) {
WeakPtr<FrameCaptureListener> listener = aListener;
if (mRequestedFrameListeners.Contains(listener)) {
return NS_OK;
}
if (!mRequestedFrameRefreshObserver) {
Document* doc = OwnerDoc();
if (!doc) {
return NS_ERROR_FAILURE;
}
PresShell* shell = nsContentUtils::FindPresShellForDocument(doc);
if (!shell) {
return NS_ERROR_FAILURE;
}
nsPresContext* context = shell->GetPresContext();
if (!context) {
return NS_ERROR_FAILURE;
}
context = context->GetRootPresContext();
if (!context) {
return NS_ERROR_FAILURE;
}
nsRefreshDriver* driver = context->RefreshDriver();
if (!driver) {
return NS_ERROR_FAILURE;
}
mRequestedFrameRefreshObserver =
new RequestedFrameRefreshObserver(this, driver, aReturnPlaceholderData);
} else {
mRequestedFrameRefreshObserver->SetReturnPlaceholderData(
aReturnPlaceholderData);
}
mRequestedFrameListeners.AppendElement(listener);
mRequestedFrameRefreshObserver->Register();
return NS_OK;
}
bool HTMLCanvasElement::IsFrameCaptureRequested(const TimeStamp& aTime) const {
for (WeakPtr<FrameCaptureListener> listener : mRequestedFrameListeners) {
if (!listener) {
continue;
}
if (listener->FrameCaptureRequested(aTime)) {
return true;
}
}
return false;
}
void HTMLCanvasElement::ProcessDestroyedFrameListeners() {
// Remove destroyed listeners from the list.
mRequestedFrameListeners.RemoveElementsBy(
[](const auto& weakListener) { return !weakListener; });
if (mRequestedFrameListeners.IsEmpty()) {
mRequestedFrameRefreshObserver->Unregister();
}
}
void HTMLCanvasElement::SetFrameCapture(
already_AddRefed<SourceSurface> aSurface, const TimeStamp& aTime) {
RefPtr<SourceSurface> surface = aSurface;
RefPtr<SourceSurfaceImage> image =
new SourceSurfaceImage(surface->GetSize(), surface);
for (WeakPtr<FrameCaptureListener> listener : mRequestedFrameListeners) {
if (!listener) {
continue;
}
RefPtr<Image> imageRefCopy = image.get();
listener->NewFrame(imageRefCopy.forget(), aTime);
}
}
already_AddRefed<SourceSurface> HTMLCanvasElement::GetSurfaceSnapshot(
gfxAlphaType* const aOutAlphaType, DrawTarget* aTarget) {
if (mCurrentContext) {
return mCurrentContext->GetOptimizedSnapshot(aTarget, aOutAlphaType);
} else if (mOffscreenDisplay) {
return mOffscreenDisplay->GetSurfaceSnapshot();
}
return nullptr;
}
layers::LayersBackend HTMLCanvasElement::GetCompositorBackendType() const {
nsIWidget* docWidget = nsContentUtils::WidgetForDocument(OwnerDoc());
if (docWidget) {
WindowRenderer* renderer = docWidget->GetWindowRenderer();
if (renderer) {
return renderer->GetCompositorBackendType();
}
}
return LayersBackend::LAYERS_NONE;
}
void HTMLCanvasElement::OnMemoryPressure() {
// FIXME(aosmond): We need to implement memory pressure handling for
// OffscreenCanvas when it is on worker threads. See bug 1746260.
if (mCurrentContext) {
mCurrentContext->OnMemoryPressure();
}
}
void HTMLCanvasElement::OnDeviceReset() {
if (!mOffscreenCanvas && mCurrentContext) {
mCurrentContext->ResetBitmap();
}
}
ClientWebGLContext* HTMLCanvasElement::GetWebGLContext() {
if (GetCurrentContextType() != CanvasContextType::WebGL1 &&
GetCurrentContextType() != CanvasContextType::WebGL2) {
return nullptr;
}
return static_cast<ClientWebGLContext*>(GetCurrentContext());
}
webgpu::CanvasContext* HTMLCanvasElement::GetWebGPUContext() {
if (GetCurrentContextType() != CanvasContextType::WebGPU) {
return nullptr;
}
return static_cast<webgpu::CanvasContext*>(GetCurrentContext());
}
} // namespace mozilla::dom