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/* -*- 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
/*
* A base class which implements nsIImageLoadingContent and can be
* subclassed by various content nodes that want to provide image
* loading functionality (eg <img>, <object>, etc).
*/
#include "nsImageLoadingContent.h"
#include "nsError.h"
#include "nsIContent.h"
#include "nsIScriptGlobalObject.h"
#include "nsServiceManagerUtils.h"
#include "nsContentList.h"
#include "nsContentPolicyUtils.h"
#include "nsIURI.h"
#include "imgIContainer.h"
#include "imgLoader.h"
#include "imgRequestProxy.h"
#include "nsThreadUtils.h"
#include "nsNetUtil.h"
#include "nsImageFrame.h"
#include "nsIChannel.h"
#include "nsIStreamListener.h"
#include "nsIFrame.h"
#include "nsContentUtils.h"
#include "nsLayoutUtils.h"
#include "nsIContentPolicy.h"
#include "mozAutoDocUpdate.h"
#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/CycleCollectedJSContext.h"
#include "mozilla/EventStateManager.h"
#include "mozilla/Preferences.h"
#include "mozilla/PresShell.h"
#include "mozilla/StaticPrefs_image.h"
#include "mozilla/SVGImageFrame.h"
#include "mozilla/SVGObserverUtils.h"
#include "mozilla/dom/BindContext.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/FetchPriority.h"
#include "mozilla/dom/PContent.h" // For TextRecognitionResult
#include "mozilla/dom/HTMLImageElement.h"
#include "mozilla/dom/ImageTextBinding.h"
#include "mozilla/dom/ImageTracker.h"
#include "mozilla/dom/ReferrerInfo.h"
#include "mozilla/dom/ScriptSettings.h"
#include "mozilla/intl/LocaleService.h"
#include "mozilla/intl/Locale.h"
#include "mozilla/dom/LargestContentfulPaint.h"
#include "mozilla/net/UrlClassifierFeatureFactory.h"
#include "mozilla/widget/TextRecognition.h"
#include "Orientation.h"
#ifdef LoadImage
// Undefine LoadImage to prevent naming conflict with Windows.
# undef LoadImage
#endif
using namespace mozilla;
using namespace mozilla::dom;
#ifdef DEBUG_chb
static void PrintReqURL(imgIRequest* req) {
if (!req) {
printf("(null req)\n");
return;
}
nsCOMPtr<nsIURI> uri;
req->GetURI(getter_AddRefs(uri));
if (!uri) {
printf("(null uri)\n");
return;
}
nsAutoCString spec;
uri->GetSpec(spec);
printf("spec='%s'\n", spec.get());
}
#endif /* DEBUG_chb */
const nsAttrValue::EnumTable nsImageLoadingContent::kDecodingTable[] = {
{"auto", nsImageLoadingContent::ImageDecodingType::Auto},
{"async", nsImageLoadingContent::ImageDecodingType::Async},
{"sync", nsImageLoadingContent::ImageDecodingType::Sync},
{nullptr, 0}};
const nsAttrValue::EnumTable* nsImageLoadingContent::kDecodingTableDefault =
&nsImageLoadingContent::kDecodingTable[0];
nsImageLoadingContent::nsImageLoadingContent()
: mObserverList(nullptr),
mOutstandingDecodePromises(0),
mRequestGeneration(0),
mLoadingEnabled(true),
mLoading(false),
mNewRequestsWillNeedAnimationReset(false),
mUseUrgentStartForChannel(false),
mLazyLoading(false),
mStateChangerDepth(0),
mCurrentRequestRegistered(false),
mPendingRequestRegistered(false),
mIsStartingImageLoad(false),
mSyncDecodingHint(false) {
if (!nsContentUtils::GetImgLoaderForChannel(nullptr, nullptr)) {
mLoadingEnabled = false;
}
mMostRecentRequestChange = TimeStamp::ProcessCreation();
}
void nsImageLoadingContent::Destroy() {
// Cancel our requests so they won't hold stale refs to us
// NB: Don't ask to discard the images here.
RejectDecodePromises(NS_ERROR_DOM_IMAGE_INVALID_REQUEST);
ClearCurrentRequest(NS_BINDING_ABORTED);
ClearPendingRequest(NS_BINDING_ABORTED);
}
nsImageLoadingContent::~nsImageLoadingContent() {
MOZ_ASSERT(!mCurrentRequest && !mPendingRequest, "Destroy not called");
MOZ_ASSERT(!mObserverList.mObserver && !mObserverList.mNext,
"Observers still registered?");
MOZ_ASSERT(mScriptedObservers.IsEmpty(),
"Scripted observers still registered?");
MOZ_ASSERT(mOutstandingDecodePromises == 0,
"Decode promises still unfulfilled?");
MOZ_ASSERT(mDecodePromises.IsEmpty(), "Decode promises still unfulfilled?");
}
/*
* imgINotificationObserver impl
*/
void nsImageLoadingContent::Notify(imgIRequest* aRequest, int32_t aType,
const nsIntRect* aData) {
MOZ_ASSERT(aRequest, "no request?");
MOZ_ASSERT(aRequest == mCurrentRequest || aRequest == mPendingRequest,
"Forgot to cancel a previous request?");
if (aType == imgINotificationObserver::IS_ANIMATED) {
return OnImageIsAnimated(aRequest);
}
if (aType == imgINotificationObserver::UNLOCKED_DRAW) {
return OnUnlockedDraw();
}
{
// Calling Notify on observers can modify the list of observers so make
// a local copy.
AutoTArray<nsCOMPtr<imgINotificationObserver>, 2> observers;
for (ImageObserver *observer = &mObserverList, *next; observer;
observer = next) {
next = observer->mNext;
if (observer->mObserver) {
observers.AppendElement(observer->mObserver);
}
}
nsAutoScriptBlocker scriptBlocker;
for (auto& observer : observers) {
observer->Notify(aRequest, aType, aData);
}
}
if (aType == imgINotificationObserver::SIZE_AVAILABLE) {
// Have to check for state changes here, since we might have been in
// the LOADING state before.
UpdateImageState(true);
}
if (aType == imgINotificationObserver::LOAD_COMPLETE) {
uint32_t reqStatus;
aRequest->GetImageStatus(&reqStatus);
/* triage STATUS_ERROR */
if (reqStatus & imgIRequest::STATUS_ERROR) {
nsresult errorCode = NS_OK;
aRequest->GetImageErrorCode(&errorCode);
/* Handle image not loading error because source was a tracking URL (or
* fingerprinting, cryptomining, etc).
* We make a note of this image node by including it in a dedicated
* array of blocked tracking nodes under its parent document.
*/
if (net::UrlClassifierFeatureFactory::IsClassifierBlockingErrorCode(
errorCode)) {
Document* doc = GetOurOwnerDoc();
doc->AddBlockedNodeByClassifier(AsContent());
}
}
nsresult status =
reqStatus & imgIRequest::STATUS_ERROR ? NS_ERROR_FAILURE : NS_OK;
return OnLoadComplete(aRequest, status);
}
if ((aType == imgINotificationObserver::FRAME_COMPLETE ||
aType == imgINotificationObserver::FRAME_UPDATE) &&
mCurrentRequest == aRequest) {
MaybeResolveDecodePromises();
}
if (aType == imgINotificationObserver::DECODE_COMPLETE) {
nsCOMPtr<imgIContainer> container;
aRequest->GetImage(getter_AddRefs(container));
if (container) {
container->PropagateUseCounters(GetOurOwnerDoc());
}
UpdateImageState(true);
}
}
void nsImageLoadingContent::OnLoadComplete(imgIRequest* aRequest,
nsresult aStatus) {
uint32_t oldStatus;
aRequest->GetImageStatus(&oldStatus);
// XXXjdm This occurs when we have a pending request created, then another
// pending request replaces it before the first one is finished.
// This begs the question of what the correct behaviour is; we used
// to not have to care because we ran this code in OnStopDecode which
// wasn't called when the first request was cancelled. For now, I choose
// to punt when the given request doesn't appear to have terminated in
// an expected state.
if (!(oldStatus &
(imgIRequest::STATUS_ERROR | imgIRequest::STATUS_LOAD_COMPLETE))) {
return;
}
// Our state may change. Watch it.
AutoStateChanger changer(this, true);
// If the pending request is loaded, switch to it.
if (aRequest == mPendingRequest) {
MakePendingRequestCurrent();
}
MOZ_ASSERT(aRequest == mCurrentRequest,
"One way or another, we should be current by now");
// Fire the appropriate DOM event.
if (NS_SUCCEEDED(aStatus)) {
FireEvent(u"load"_ns);
} else {
FireEvent(u"error"_ns);
}
Element* element = AsContent()->AsElement();
SVGObserverUtils::InvalidateDirectRenderingObservers(element);
MaybeResolveDecodePromises();
LargestContentfulPaint::MaybeProcessImageForElementTiming(mCurrentRequest,
element);
}
void nsImageLoadingContent::OnUnlockedDraw() {
// This notification is only sent for animated images. It's OK for
// non-animated images to wait until the next frame visibility update to
// become locked. (And that's preferable, since in the case of scrolling it
// keeps memory usage minimal.)
//
// For animated images, though, we want to mark them visible right away so we
// can call IncrementAnimationConsumers() on them and they'll start animating.
nsIFrame* frame = GetOurPrimaryImageFrame();
if (!frame) {
return;
}
if (frame->GetVisibility() == Visibility::ApproximatelyVisible) {
// This frame is already marked visible; there's nothing to do.
return;
}
nsPresContext* presContext = frame->PresContext();
if (!presContext) {
return;
}
PresShell* presShell = presContext->GetPresShell();
if (!presShell) {
return;
}
presShell->EnsureFrameInApproximatelyVisibleList(frame);
}
void nsImageLoadingContent::OnImageIsAnimated(imgIRequest* aRequest) {
bool* requestFlag = nullptr;
if (aRequest == mCurrentRequest) {
requestFlag = &mCurrentRequestRegistered;
} else if (aRequest == mPendingRequest) {
requestFlag = &mPendingRequestRegistered;
} else {
MOZ_ASSERT_UNREACHABLE("Which image is this?");
return;
}
nsLayoutUtils::RegisterImageRequest(GetFramePresContext(), aRequest,
requestFlag);
}
static bool IsOurImageFrame(nsIFrame* aFrame) {
if (nsImageFrame* f = do_QueryFrame(aFrame)) {
return f->IsForImageLoadingContent();
}
return aFrame->IsSVGImageFrame() || aFrame->IsSVGFEImageFrame();
}
nsIFrame* nsImageLoadingContent::GetOurPrimaryImageFrame() {
nsIFrame* frame = AsContent()->GetPrimaryFrame();
if (!frame || !IsOurImageFrame(frame)) {
return nullptr;
}
return frame;
}
/*
* nsIImageLoadingContent impl
*/
void nsImageLoadingContent::SetLoadingEnabled(bool aLoadingEnabled) {
if (nsContentUtils::GetImgLoaderForChannel(nullptr, nullptr)) {
mLoadingEnabled = aLoadingEnabled;
}
}
nsresult nsImageLoadingContent::GetSyncDecodingHint(bool* aHint) {
*aHint = mSyncDecodingHint;
return NS_OK;
}
already_AddRefed<Promise> nsImageLoadingContent::QueueDecodeAsync(
ErrorResult& aRv) {
Document* doc = GetOurOwnerDoc();
RefPtr<Promise> promise = Promise::Create(doc->GetScopeObject(), aRv);
if (aRv.Failed()) {
return nullptr;
}
class QueueDecodeTask final : public MicroTaskRunnable {
public:
QueueDecodeTask(nsImageLoadingContent* aOwner, Promise* aPromise,
uint32_t aRequestGeneration)
: mOwner(aOwner),
mPromise(aPromise),
mRequestGeneration(aRequestGeneration) {}
virtual void Run(AutoSlowOperation& aAso) override {
mOwner->DecodeAsync(std::move(mPromise), mRequestGeneration);
}
virtual bool Suppressed() override {
nsIGlobalObject* global = mOwner->GetOurOwnerDoc()->GetScopeObject();
return global && global->IsInSyncOperation();
}
private:
RefPtr<nsImageLoadingContent> mOwner;
RefPtr<Promise> mPromise;
uint32_t mRequestGeneration;
};
if (++mOutstandingDecodePromises == 1) {
MOZ_ASSERT(mDecodePromises.IsEmpty());
doc->RegisterActivityObserver(AsContent()->AsElement());
}
auto task = MakeRefPtr<QueueDecodeTask>(this, promise, mRequestGeneration);
CycleCollectedJSContext::Get()->DispatchToMicroTask(task.forget());
return promise.forget();
}
void nsImageLoadingContent::DecodeAsync(RefPtr<Promise>&& aPromise,
uint32_t aRequestGeneration) {
MOZ_ASSERT(aPromise);
MOZ_ASSERT(mOutstandingDecodePromises > mDecodePromises.Length());
// The request may have gotten updated since the decode call was issued.
if (aRequestGeneration != mRequestGeneration) {
aPromise->MaybeReject(NS_ERROR_DOM_IMAGE_INVALID_REQUEST);
// We never got placed in mDecodePromises, so we must ensure we decrement
// the counter explicitly.
--mOutstandingDecodePromises;
MaybeDeregisterActivityObserver();
return;
}
bool wasEmpty = mDecodePromises.IsEmpty();
mDecodePromises.AppendElement(std::move(aPromise));
if (wasEmpty) {
MaybeResolveDecodePromises();
}
}
void nsImageLoadingContent::MaybeResolveDecodePromises() {
if (mDecodePromises.IsEmpty()) {
return;
}
if (!mCurrentRequest) {
RejectDecodePromises(NS_ERROR_DOM_IMAGE_INVALID_REQUEST);
return;
}
// Only can resolve if our document is the active document. If not we are
// supposed to reject the promise, even if it was fulfilled successfully.
if (!GetOurOwnerDoc()->IsCurrentActiveDocument()) {
RejectDecodePromises(NS_ERROR_DOM_IMAGE_INACTIVE_DOCUMENT);
return;
}
// If any error occurred while decoding, we need to reject first.
uint32_t status = imgIRequest::STATUS_NONE;
mCurrentRequest->GetImageStatus(&status);
if (status & imgIRequest::STATUS_ERROR) {
RejectDecodePromises(NS_ERROR_DOM_IMAGE_BROKEN);
return;
}
// We need the size to bother with requesting a decode, as we are either
// blocked on validation or metadata decoding.
if (!(status & imgIRequest::STATUS_SIZE_AVAILABLE)) {
return;
}
// Check the surface cache status and/or request decoding begin. We do this
// before LOAD_COMPLETE because we want to start as soon as possible.
uint32_t flags = imgIContainer::FLAG_HIGH_QUALITY_SCALING |
imgIContainer::FLAG_AVOID_REDECODE_FOR_SIZE;
imgIContainer::DecodeResult decodeResult =
mCurrentRequest->RequestDecodeWithResult(flags);
if (decodeResult == imgIContainer::DECODE_REQUESTED) {
return;
}
if (decodeResult == imgIContainer::DECODE_REQUEST_FAILED) {
RejectDecodePromises(NS_ERROR_DOM_IMAGE_BROKEN);
return;
}
MOZ_ASSERT(decodeResult == imgIContainer::DECODE_SURFACE_AVAILABLE);
// We can only fulfill the promises once we have all the data.
if (!(status & imgIRequest::STATUS_LOAD_COMPLETE)) {
return;
}
for (auto& promise : mDecodePromises) {
promise->MaybeResolveWithUndefined();
}
MOZ_ASSERT(mOutstandingDecodePromises >= mDecodePromises.Length());
mOutstandingDecodePromises -= mDecodePromises.Length();
mDecodePromises.Clear();
MaybeDeregisterActivityObserver();
}
void nsImageLoadingContent::RejectDecodePromises(nsresult aStatus) {
if (mDecodePromises.IsEmpty()) {
return;
}
for (auto& promise : mDecodePromises) {
promise->MaybeReject(aStatus);
}
MOZ_ASSERT(mOutstandingDecodePromises >= mDecodePromises.Length());
mOutstandingDecodePromises -= mDecodePromises.Length();
mDecodePromises.Clear();
MaybeDeregisterActivityObserver();
}
void nsImageLoadingContent::MaybeAgeRequestGeneration(nsIURI* aNewURI) {
MOZ_ASSERT(mCurrentRequest);
// If the current request is about to change, we need to verify if the new
// URI matches the existing current request's URI. If it doesn't, we need to
// reject any outstanding promises due to the current request mutating as per
// step 2.2 of the decode API requirements.
//
if (aNewURI) {
nsCOMPtr<nsIURI> currentURI;
mCurrentRequest->GetURI(getter_AddRefs(currentURI));
bool equal = false;
if (NS_SUCCEEDED(aNewURI->Equals(currentURI, &equal)) && equal) {
return;
}
}
++mRequestGeneration;
RejectDecodePromises(NS_ERROR_DOM_IMAGE_INVALID_REQUEST);
}
void nsImageLoadingContent::MaybeDeregisterActivityObserver() {
if (mOutstandingDecodePromises == 0) {
MOZ_ASSERT(mDecodePromises.IsEmpty());
GetOurOwnerDoc()->UnregisterActivityObserver(AsContent()->AsElement());
}
}
void nsImageLoadingContent::SetSyncDecodingHint(bool aHint) {
if (mSyncDecodingHint == aHint) {
return;
}
mSyncDecodingHint = aHint;
MaybeForceSyncDecoding(/* aPrepareNextRequest */ false);
}
void nsImageLoadingContent::MaybeForceSyncDecoding(
bool aPrepareNextRequest, nsIFrame* aFrame /* = nullptr */) {
// GetOurPrimaryImageFrame() might not return the frame during frame init.
nsIFrame* frame = aFrame ? aFrame : GetOurPrimaryImageFrame();
if (!frame) {
return;
}
bool forceSync = mSyncDecodingHint;
if (!forceSync && aPrepareNextRequest) {
// Detect JavaScript-based animations created by changing the |src|
// attribute on a timer.
TimeStamp now = TimeStamp::Now();
TimeDuration threshold = TimeDuration::FromMilliseconds(
StaticPrefs::image_infer_src_animation_threshold_ms());
// If the length of time between request changes is less than the threshold,
// then force sync decoding to eliminate flicker from the animation.
forceSync = (now - mMostRecentRequestChange < threshold);
mMostRecentRequestChange = now;
}
if (nsImageFrame* imageFrame = do_QueryFrame(frame)) {
imageFrame->SetForceSyncDecoding(forceSync);
} else if (SVGImageFrame* svgImageFrame = do_QueryFrame(frame)) {
svgImageFrame->SetForceSyncDecoding(forceSync);
}
}
static void ReplayImageStatus(imgIRequest* aRequest,
imgINotificationObserver* aObserver) {
if (!aRequest) {
return;
}
uint32_t status = 0;
nsresult rv = aRequest->GetImageStatus(&status);
if (NS_FAILED(rv)) {
return;
}
if (status & imgIRequest::STATUS_SIZE_AVAILABLE) {
aObserver->Notify(aRequest, imgINotificationObserver::SIZE_AVAILABLE,
nullptr);
}
if (status & imgIRequest::STATUS_FRAME_COMPLETE) {
aObserver->Notify(aRequest, imgINotificationObserver::FRAME_COMPLETE,
nullptr);
}
if (status & imgIRequest::STATUS_HAS_TRANSPARENCY) {
aObserver->Notify(aRequest, imgINotificationObserver::HAS_TRANSPARENCY,
nullptr);
}
if (status & imgIRequest::STATUS_IS_ANIMATED) {
aObserver->Notify(aRequest, imgINotificationObserver::IS_ANIMATED, nullptr);
}
if (status & imgIRequest::STATUS_DECODE_COMPLETE) {
aObserver->Notify(aRequest, imgINotificationObserver::DECODE_COMPLETE,
nullptr);
}
if (status & imgIRequest::STATUS_LOAD_COMPLETE) {
aObserver->Notify(aRequest, imgINotificationObserver::LOAD_COMPLETE,
nullptr);
}
}
void nsImageLoadingContent::AddNativeObserver(
imgINotificationObserver* aObserver) {
if (NS_WARN_IF(!aObserver)) {
return;
}
if (!mObserverList.mObserver) {
// Don't touch the linking of the list!
mObserverList.mObserver = aObserver;
ReplayImageStatus(mCurrentRequest, aObserver);
ReplayImageStatus(mPendingRequest, aObserver);
return;
}
// otherwise we have to create a new entry
ImageObserver* observer = &mObserverList;
while (observer->mNext) {
observer = observer->mNext;
}
observer->mNext = new ImageObserver(aObserver);
ReplayImageStatus(mCurrentRequest, aObserver);
ReplayImageStatus(mPendingRequest, aObserver);
}
void nsImageLoadingContent::RemoveNativeObserver(
imgINotificationObserver* aObserver) {
if (NS_WARN_IF(!aObserver)) {
return;
}
if (mObserverList.mObserver == aObserver) {
mObserverList.mObserver = nullptr;
// Don't touch the linking of the list!
return;
}
// otherwise have to find it and splice it out
ImageObserver* observer = &mObserverList;
while (observer->mNext && observer->mNext->mObserver != aObserver) {
observer = observer->mNext;
}
// At this point, we are pointing to the list element whose mNext is
// the right observer (assuming of course that mNext is not null)
if (observer->mNext) {
// splice it out
ImageObserver* oldObserver = observer->mNext;
observer->mNext = oldObserver->mNext;
oldObserver->mNext = nullptr; // so we don't destroy them all
delete oldObserver;
}
#ifdef DEBUG
else {
NS_WARNING("Asked to remove nonexistent observer");
}
#endif
}
void nsImageLoadingContent::AddObserver(imgINotificationObserver* aObserver) {
if (NS_WARN_IF(!aObserver)) {
return;
}
RefPtr<imgRequestProxy> currentReq;
if (mCurrentRequest) {
// Scripted observers may not belong to the same document as us, so when we
// create the imgRequestProxy, we shouldn't use any. This allows the request
// to dispatch notifications from the correct scheduler group.
nsresult rv =
mCurrentRequest->Clone(aObserver, nullptr, getter_AddRefs(currentReq));
if (NS_FAILED(rv)) {
return;
}
}
RefPtr<imgRequestProxy> pendingReq;
if (mPendingRequest) {
// See above for why we don't use the loading document.
nsresult rv =
mPendingRequest->Clone(aObserver, nullptr, getter_AddRefs(pendingReq));
if (NS_FAILED(rv)) {
mCurrentRequest->CancelAndForgetObserver(NS_BINDING_ABORTED);
return;
}
}
mScriptedObservers.AppendElement(new ScriptedImageObserver(
aObserver, std::move(currentReq), std::move(pendingReq)));
}
void nsImageLoadingContent::RemoveObserver(
imgINotificationObserver* aObserver) {
if (NS_WARN_IF(!aObserver)) {
return;
}
if (NS_WARN_IF(mScriptedObservers.IsEmpty())) {
return;
}
RefPtr<ScriptedImageObserver> observer;
auto i = mScriptedObservers.Length();
do {
--i;
if (mScriptedObservers[i]->mObserver == aObserver) {
observer = std::move(mScriptedObservers[i]);
mScriptedObservers.RemoveElementAt(i);
break;
}
} while (i > 0);
if (NS_WARN_IF(!observer)) {
return;
}
// If the cancel causes a mutation, it will be harmless, because we have
// already removed the observer from the list.
observer->CancelRequests();
}
void nsImageLoadingContent::ClearScriptedRequests(int32_t aRequestType,
nsresult aReason) {
if (MOZ_LIKELY(mScriptedObservers.IsEmpty())) {
return;
}
nsTArray<RefPtr<ScriptedImageObserver>> observers(mScriptedObservers.Clone());
auto i = observers.Length();
do {
--i;
RefPtr<imgRequestProxy> req;
switch (aRequestType) {
case CURRENT_REQUEST:
req = std::move(observers[i]->mCurrentRequest);
break;
case PENDING_REQUEST:
req = std::move(observers[i]->mPendingRequest);
break;
default:
NS_ERROR("Unknown request type");
return;
}
if (req) {
req->CancelAndForgetObserver(aReason);
}
} while (i > 0);
}
void nsImageLoadingContent::CloneScriptedRequests(imgRequestProxy* aRequest) {
MOZ_ASSERT(aRequest);
if (MOZ_LIKELY(mScriptedObservers.IsEmpty())) {
return;
}
bool current;
if (aRequest == mCurrentRequest) {
current = true;
} else if (aRequest == mPendingRequest) {
current = false;
} else {
MOZ_ASSERT_UNREACHABLE("Unknown request type");
return;
}
nsTArray<RefPtr<ScriptedImageObserver>> observers(mScriptedObservers.Clone());
auto i = observers.Length();
do {
--i;
ScriptedImageObserver* observer = observers[i];
RefPtr<imgRequestProxy>& req =
current ? observer->mCurrentRequest : observer->mPendingRequest;
if (NS_WARN_IF(req)) {
MOZ_ASSERT_UNREACHABLE("Should have cancelled original request");
req->CancelAndForgetObserver(NS_BINDING_ABORTED);
req = nullptr;
}
nsresult rv =
aRequest->Clone(observer->mObserver, nullptr, getter_AddRefs(req));
Unused << NS_WARN_IF(NS_FAILED(rv));
} while (i > 0);
}
void nsImageLoadingContent::MakePendingScriptedRequestsCurrent() {
if (MOZ_LIKELY(mScriptedObservers.IsEmpty())) {
return;
}
nsTArray<RefPtr<ScriptedImageObserver>> observers(mScriptedObservers.Clone());
auto i = observers.Length();
do {
--i;
ScriptedImageObserver* observer = observers[i];
if (observer->mCurrentRequest) {
observer->mCurrentRequest->CancelAndForgetObserver(NS_BINDING_ABORTED);
}
observer->mCurrentRequest = std::move(observer->mPendingRequest);
} while (i > 0);
}
already_AddRefed<imgIRequest> nsImageLoadingContent::GetRequest(
int32_t aRequestType, ErrorResult& aError) {
nsCOMPtr<imgIRequest> request;
switch (aRequestType) {
case CURRENT_REQUEST:
request = mCurrentRequest;
break;
case PENDING_REQUEST:
request = mPendingRequest;
break;
default:
NS_ERROR("Unknown request type");
aError.Throw(NS_ERROR_UNEXPECTED);
}
return request.forget();
}
NS_IMETHODIMP
nsImageLoadingContent::GetRequest(int32_t aRequestType,
imgIRequest** aRequest) {
NS_ENSURE_ARG_POINTER(aRequest);
ErrorResult result;
*aRequest = GetRequest(aRequestType, result).take();
return result.StealNSResult();
}
NS_IMETHODIMP_(void)
nsImageLoadingContent::FrameCreated(nsIFrame* aFrame) {
MOZ_ASSERT(aFrame, "aFrame is null");
MOZ_ASSERT(IsOurImageFrame(aFrame));
MaybeForceSyncDecoding(/* aPrepareNextRequest */ false, aFrame);
TrackImage(mCurrentRequest, aFrame);
TrackImage(mPendingRequest, aFrame);
// We need to make sure that our image request is registered, if it should
// be registered.
nsPresContext* presContext = aFrame->PresContext();
if (mCurrentRequest) {
nsLayoutUtils::RegisterImageRequestIfAnimated(presContext, mCurrentRequest,
&mCurrentRequestRegistered);
}
if (mPendingRequest) {
nsLayoutUtils::RegisterImageRequestIfAnimated(presContext, mPendingRequest,
&mPendingRequestRegistered);
}
}
NS_IMETHODIMP_(void)
nsImageLoadingContent::FrameDestroyed(nsIFrame* aFrame) {
NS_ASSERTION(aFrame, "aFrame is null");
// We need to make sure that our image request is deregistered.
nsPresContext* presContext = GetFramePresContext();
if (mCurrentRequest) {
nsLayoutUtils::DeregisterImageRequest(presContext, mCurrentRequest,
&mCurrentRequestRegistered);
}
if (mPendingRequest) {
nsLayoutUtils::DeregisterImageRequest(presContext, mPendingRequest,
&mPendingRequestRegistered);
}
UntrackImage(mCurrentRequest);
UntrackImage(mPendingRequest);
PresShell* presShell = presContext ? presContext->GetPresShell() : nullptr;
if (presShell) {
presShell->RemoveFrameFromApproximatelyVisibleList(aFrame);
}
}
/* static */
nsContentPolicyType nsImageLoadingContent::PolicyTypeForLoad(
ImageLoadType aImageLoadType) {
if (aImageLoadType == eImageLoadType_Imageset) {
return nsIContentPolicy::TYPE_IMAGESET;
}
MOZ_ASSERT(aImageLoadType == eImageLoadType_Normal,
"Unknown ImageLoadType type in PolicyTypeForLoad");
return nsIContentPolicy::TYPE_INTERNAL_IMAGE;
}
int32_t nsImageLoadingContent::GetRequestType(imgIRequest* aRequest,
ErrorResult& aError) {
if (aRequest == mCurrentRequest) {
return CURRENT_REQUEST;
}
if (aRequest == mPendingRequest) {
return PENDING_REQUEST;
}
NS_ERROR("Unknown request");
aError.Throw(NS_ERROR_UNEXPECTED);
return UNKNOWN_REQUEST;
}
NS_IMETHODIMP
nsImageLoadingContent::GetRequestType(imgIRequest* aRequest,
int32_t* aRequestType) {
MOZ_ASSERT(aRequestType, "Null out param");
ErrorResult result;
*aRequestType = GetRequestType(aRequest, result);
return result.StealNSResult();
}
already_AddRefed<nsIURI> nsImageLoadingContent::GetCurrentURI() {
nsCOMPtr<nsIURI> uri;
if (mCurrentRequest) {
mCurrentRequest->GetURI(getter_AddRefs(uri));
} else {
uri = mCurrentURI;
}
return uri.forget();
}
NS_IMETHODIMP
nsImageLoadingContent::GetCurrentURI(nsIURI** aURI) {
NS_ENSURE_ARG_POINTER(aURI);
*aURI = GetCurrentURI().take();
return NS_OK;
}
already_AddRefed<nsIURI> nsImageLoadingContent::GetCurrentRequestFinalURI() {
nsCOMPtr<nsIURI> uri;
if (mCurrentRequest) {
mCurrentRequest->GetFinalURI(getter_AddRefs(uri));
}
return uri.forget();
}
NS_IMETHODIMP
nsImageLoadingContent::LoadImageWithChannel(nsIChannel* aChannel,
nsIStreamListener** aListener) {
imgLoader* loader =
nsContentUtils::GetImgLoaderForChannel(aChannel, GetOurOwnerDoc());
if (!loader) {
return NS_ERROR_NULL_POINTER;
}
nsCOMPtr<Document> doc = GetOurOwnerDoc();
if (!doc) {
// Don't bother
*aListener = nullptr;
return NS_OK;
}
// XXX what should we do with content policies here, if anything?
// Shouldn't that be done before the start of the load?
// XXX what about shouldProcess?
// If we have a current request without a size, we know we will replace it
// with the PrepareNextRequest below. If the new current request is for a
// different URI, then we need to reject any outstanding promises.
if (mCurrentRequest && !HaveSize(mCurrentRequest)) {
nsCOMPtr<nsIURI> uri;
aChannel->GetOriginalURI(getter_AddRefs(uri));
MaybeAgeRequestGeneration(uri);
}
// Our state might change. Watch it.
AutoStateChanger changer(this, true);
// Do the load.
RefPtr<imgRequestProxy>& req = PrepareNextRequest(eImageLoadType_Normal);
nsresult rv = loader->LoadImageWithChannel(aChannel, this, doc, aListener,
getter_AddRefs(req));
if (NS_SUCCEEDED(rv)) {
CloneScriptedRequests(req);
TrackImage(req);
ResetAnimationIfNeeded();
return NS_OK;
}
MOZ_ASSERT(!req, "Shouldn't have non-null request here");
// If we don't have a current URI, we might as well store this URI so people
// know what we tried (and failed) to load.
if (!mCurrentRequest) aChannel->GetURI(getter_AddRefs(mCurrentURI));
FireEvent(u"error"_ns);
return rv;
}
void nsImageLoadingContent::ForceReload(bool aNotify, ErrorResult& aError) {
nsCOMPtr<nsIURI> currentURI;
GetCurrentURI(getter_AddRefs(currentURI));
if (!currentURI) {
aError.Throw(NS_ERROR_NOT_AVAILABLE);
return;
}
// We keep this flag around along with the old URI even for failed requests
// without a live request object
ImageLoadType loadType = (mCurrentRequestFlags & REQUEST_IS_IMAGESET)
? eImageLoadType_Imageset
: eImageLoadType_Normal;
nsresult rv = LoadImage(currentURI, true, aNotify, loadType,
nsIRequest::VALIDATE_ALWAYS | LoadFlags());
if (NS_FAILED(rv)) {
aError.Throw(rv);
}
}
/*
* Non-interface methods
*/
nsresult nsImageLoadingContent::LoadImage(const nsAString& aNewURI, bool aForce,
bool aNotify,
ImageLoadType aImageLoadType,
nsIPrincipal* aTriggeringPrincipal) {
// First, get a document (needed for security checks and the like)
Document* doc = GetOurOwnerDoc();
if (!doc) {
// No reason to bother, I think...
return NS_OK;
}
// Parse the URI string to get image URI
nsCOMPtr<nsIURI> imageURI;
if (!aNewURI.IsEmpty()) {
Unused << StringToURI(aNewURI, doc, getter_AddRefs(imageURI));
}
return LoadImage(imageURI, aForce, aNotify, aImageLoadType, LoadFlags(), doc,
aTriggeringPrincipal);
}
nsresult nsImageLoadingContent::LoadImage(nsIURI* aNewURI, bool aForce,
bool aNotify,
ImageLoadType aImageLoadType,
nsLoadFlags aLoadFlags,
Document* aDocument,
nsIPrincipal* aTriggeringPrincipal) {
MOZ_ASSERT(!mIsStartingImageLoad, "some evil code is reentering LoadImage.");
if (mIsStartingImageLoad) {
return NS_OK;
}
// Pending load/error events need to be canceled in some situations. This
// is not documented in the spec, but can cause site compat problems if not
CancelPendingEvent();
if (!aNewURI) {
// Cancel image requests and then fire only error event per spec.
CancelImageRequests(aNotify);
if (aImageLoadType == eImageLoadType_Normal) {
// Mark error event as cancelable only for src="" case, since only this
FireEvent(u"error"_ns, true);
}
return NS_OK;
}
if (!mLoadingEnabled) {
// XXX Why fire an error here? seems like the callers to SetLoadingEnabled
// don't want/need it.
FireEvent(u"error"_ns);
return NS_OK;
}
NS_ASSERTION(!aDocument || aDocument == GetOurOwnerDoc(),
"Bogus document passed in");
// First, get a document (needed for security checks and the like)
if (!aDocument) {
aDocument = GetOurOwnerDoc();
if (!aDocument) {
// No reason to bother, I think...
return NS_OK;
}
}
AutoRestore<bool> guard(mIsStartingImageLoad);
mIsStartingImageLoad = true;
// Data documents, or documents from DOMParser shouldn't perform image
// loading.
//
// FIXME(emilio): Shouldn't this check be part of
// Document::ShouldLoadImages()? Or alternatively check ShouldLoadImages here
// instead? (It seems we only check ShouldLoadImages in HTMLImageElement,
// which seems wrong...)
if (aDocument->IsLoadedAsData() && !aDocument->IsStaticDocument()) {
// Clear our pending request if we do have one.
ClearPendingRequest(NS_BINDING_ABORTED, Some(OnNonvisible::DiscardImages));
FireEvent(u"error"_ns);
return NS_OK;
}
// URI equality check.
//
// We skip the equality check if we don't have a current image, since in that
// case we really do want to try loading again.
if (!aForce && mCurrentRequest) {
nsCOMPtr<nsIURI> currentURI;
GetCurrentURI(getter_AddRefs(currentURI));
bool equal;
if (currentURI && NS_SUCCEEDED(currentURI->Equals(aNewURI, &equal)) &&
equal) {
// Nothing to do here.
return NS_OK;
}
}
// If we have a current request without a size, we know we will replace it
// with the PrepareNextRequest below. If the new current request is for a
// different URI, then we need to reject any outstanding promises.
if (mCurrentRequest && !HaveSize(mCurrentRequest)) {
MaybeAgeRequestGeneration(aNewURI);
}
// From this point on, our image state could change. Watch it.
AutoStateChanger changer(this, aNotify);
// Sanity check.
//
// We use the principal of aDocument to avoid having to QI |this| an extra
// time. It should always be the same as the principal of this node.
Element* element = AsContent()->AsElement();
MOZ_ASSERT(element->NodePrincipal() == aDocument->NodePrincipal(),
"Principal mismatch?");
nsLoadFlags loadFlags =
aLoadFlags | nsContentUtils::CORSModeToLoadImageFlags(GetCORSMode());
RefPtr<imgRequestProxy>& req = PrepareNextRequest(aImageLoadType);
nsCOMPtr<nsIPrincipal> triggeringPrincipal;
bool result = nsContentUtils::QueryTriggeringPrincipal(
element, aTriggeringPrincipal, getter_AddRefs(triggeringPrincipal));
// If result is true, which means this node has specified
// 'triggeringprincipal' attribute on it, so we use favicon as the policy
// type.
nsContentPolicyType policyType =
result ? nsIContentPolicy::TYPE_INTERNAL_IMAGE_FAVICON
: PolicyTypeForLoad(aImageLoadType);
auto referrerInfo = MakeRefPtr<ReferrerInfo>(*element);
nsresult rv = nsContentUtils::LoadImage(
aNewURI, element, aDocument, triggeringPrincipal, 0, referrerInfo, this,
loadFlags, element->LocalName(), getter_AddRefs(req), policyType,
mUseUrgentStartForChannel, /* aLinkPreload */ false,
/* aEarlyHintPreloaderId */ 0, GetFetchPriorityForImage());
// Reset the flag to avoid loading from XPCOM or somewhere again else without
// initiated by user interaction.
mUseUrgentStartForChannel = false;
// Tell the document to forget about the image preload, if any, for
// this URI, now that we might have another imgRequestProxy for it.
// That way if we get canceled later the image load won't continue.
aDocument->ForgetImagePreload(aNewURI);
if (NS_SUCCEEDED(rv)) {
// Based on performance testing unsuppressing painting soon after the page
// has gotten an image may improve visual metrics.
if (Document* doc = element->GetComposedDoc()) {
if (PresShell* shell = doc->GetPresShell()) {
shell->TryUnsuppressPaintingSoon();
}
}
CloneScriptedRequests(req);
TrackImage(req);
ResetAnimationIfNeeded();
// Handle cases when we just ended up with a request but it's already done.
// In that situation we have to synchronously switch that request to being
// the current request, because websites depend on that behavior.
{
uint32_t loadStatus;
if (NS_SUCCEEDED(req->GetImageStatus(&loadStatus)) &&
(loadStatus & imgIRequest::STATUS_LOAD_COMPLETE)) {
if (req == mPendingRequest) {
MakePendingRequestCurrent();
}
MOZ_ASSERT(mCurrentRequest,
"How could we not have a current request here?");
if (nsImageFrame* f = do_QueryFrame(GetOurPrimaryImageFrame())) {
f->NotifyNewCurrentRequest(mCurrentRequest, NS_OK);
}
}
}
} else {
MOZ_ASSERT(!req, "Shouldn't have non-null request here");
// If we don't have a current URI, we might as well store this URI so people
// know what we tried (and failed) to load.
if (!mCurrentRequest) {
mCurrentURI = aNewURI;
}
FireEvent(u"error"_ns);
}
return NS_OK;
}
already_AddRefed<Promise> nsImageLoadingContent::RecognizeCurrentImageText(
ErrorResult& aRv) {
using widget::TextRecognition;
if (!mCurrentRequest) {
aRv.ThrowInvalidStateError("No current request");
return nullptr;
}
nsCOMPtr<imgIContainer> image;
mCurrentRequest->GetImage(getter_AddRefs(image));
if (!image) {
aRv.ThrowInvalidStateError("No image");
return nullptr;
}
RefPtr<Promise> domPromise =
Promise::Create(GetOurOwnerDoc()->GetScopeObject(), aRv);
if (aRv.Failed()) {
return nullptr;
}
// The list of ISO 639-1 language tags to pass to the text recognition API.
AutoTArray<nsCString, 4> languages;
{
// The document's locale should be the top language to use. Parse the BCP 47
// locale and extract the ISO 639-1 language tag. e.g. "en-US" -> "en".
nsAutoCString elementLanguage;
nsAtom* imgLanguage = AsContent()->GetLang();
intl::Locale locale;
if (imgLanguage) {
imgLanguage->ToUTF8String(elementLanguage);
auto result = intl::LocaleParser::TryParse(elementLanguage, locale);
if (result.isOk()) {
languages.AppendElement(locale.Language().Span());
}
}
}
{
// The app locales should also be included after the document's locales.
// Extract the language tag like above.
nsTArray<nsCString> appLocales;
intl::LocaleService::GetInstance()->GetAppLocalesAsBCP47(appLocales);
for (const auto& localeString : appLocales) {
intl::Locale locale;
auto result = intl::LocaleParser::TryParse(localeString, locale);
if (result.isErr()) {
NS_WARNING("Could not parse an app locale string, ignoring it.");
continue;
}
languages.AppendElement(locale.Language().Span());
}
}
TextRecognition::FindText(*image, languages)
->Then(
GetCurrentSerialEventTarget(), __func__,
[weak = RefPtr{do_GetWeakReference(this)},
request = RefPtr{mCurrentRequest}, domPromise](
TextRecognition::NativePromise::ResolveOrRejectValue&& aValue) {
if (aValue.IsReject()) {
domPromise->MaybeRejectWithNotSupportedError(
aValue.RejectValue());
return;
}
RefPtr<nsIImageLoadingContent> iilc = do_QueryReferent(weak.get());
if (!iilc) {
domPromise->MaybeRejectWithInvalidStateError(
"Element was dead when we got the results");
return;
}
auto* ilc = static_cast<nsImageLoadingContent*>(iilc.get());
if (ilc->mCurrentRequest != request) {
domPromise->MaybeRejectWithInvalidStateError(
"Request not current");
return;
}
auto& textRecognitionResult = aValue.ResolveValue();
Element* el = ilc->AsContent()->AsElement();
// When enabled, this feature will place the recognized text as
// spans inside of the shadow dom of the img element. These are then
// positioned so that the user can select the text.
if (Preferences::GetBool("dom.text-recognition.shadow-dom-enabled",
false)) {
el->AttachAndSetUAShadowRoot(Element::NotifyUAWidgetSetup::Yes);
TextRecognition::FillShadow(*el->GetShadowRoot(),
textRecognitionResult);
el->NotifyUAWidgetSetupOrChange();
}
nsTArray<ImageText> imageTexts(
textRecognitionResult.quads().Length());
nsIGlobalObject* global = el->OwnerDoc()->GetOwnerGlobal();
for (const auto& quad : textRecognitionResult.quads()) {
NotNull<ImageText*> imageText = imageTexts.AppendElement();
// Note: These points are not actually CSSPixels, but a DOMQuad is
// a conveniently similar structure that can store these values.
CSSPoint points[4];
points[0] = CSSPoint(quad.points()[0].x, quad.points()[0].y);
points[1] = CSSPoint(quad.points()[1].x, quad.points()[1].y);
points[2] = CSSPoint(quad.points()[2].x, quad.points()[2].y);
points[3] = CSSPoint(quad.points()[3].x, quad.points()[3].y);
imageText->mQuad = new DOMQuad(global, points);
imageText->mConfidence = quad.confidence();
imageText->mString = quad.string();
}
domPromise->MaybeResolve(std::move(imageTexts));
});
return domPromise.forget();
}
CSSIntSize nsImageLoadingContent::GetWidthHeightForImage() {
Element* element = AsContent()->AsElement();
if (nsIFrame* frame = element->GetPrimaryFrame(FlushType::Layout)) {
return CSSIntSize::FromAppUnitsRounded(frame->GetContentRect().Size());
}
const nsAttrValue* value;
nsCOMPtr<imgIContainer> image;
if (mCurrentRequest) {
mCurrentRequest->GetImage(getter_AddRefs(image));
}
CSSIntSize size;
if ((value = element->GetParsedAttr(nsGkAtoms::width)) &&
value->Type() == nsAttrValue::eInteger) {
size.width = value->GetIntegerValue();
} else if (image) {
image->GetWidth(&size.width);
}
if ((value = element->GetParsedAttr(nsGkAtoms::height)) &&
value->Type() == nsAttrValue::eInteger) {
size.height = value->GetIntegerValue();
} else if (image) {
image->GetHeight(&size.height);
}
NS_ASSERTION(size.width >= 0, "negative width");
NS_ASSERTION(size.height >= 0, "negative height");
return size;
}
void nsImageLoadingContent::UpdateImageState(bool aNotify) {
if (mStateChangerDepth > 0) {
// Ignore this call; we'll update our state when the outermost state changer
// is destroyed. Need this to work around the fact that some ImageLib
// stuff is actually sync and hence we can get OnStopDecode called while
// we're still under LoadImage, and OnStopDecode doesn't know anything about
// aNotify.
return;
}
Element* thisElement = AsContent()->AsElement();
mLoading = false;
Element::AutoStateChangeNotifier notifier(*thisElement, aNotify);
thisElement->RemoveStatesSilently(ElementState::BROKEN);
// If we were blocked, we're broken, so are we if we don't have an image
// request at all or the image has errored.
if (!mCurrentRequest) {
if (!mLazyLoading) {
// In case of non-lazy loading, no current request means error, since we
// weren't disabled or suppressed
thisElement->AddStatesSilently(ElementState::BROKEN);
RejectDecodePromises(NS_ERROR_DOM_IMAGE_BROKEN);
}
} else {
uint32_t currentLoadStatus;
nsresult rv = mCurrentRequest->GetImageStatus(¤tLoadStatus);
if (NS_FAILED(rv) || (currentLoadStatus & imgIRequest::STATUS_ERROR)) {
thisElement->AddStatesSilently(ElementState::BROKEN);
RejectDecodePromises(NS_ERROR_DOM_IMAGE_BROKEN);
} else if (!(currentLoadStatus & imgIRequest::STATUS_SIZE_AVAILABLE)) {
mLoading = true;
}
}
}
void nsImageLoadingContent::CancelImageRequests(bool aNotify) {
RejectDecodePromises(NS_ERROR_DOM_IMAGE_INVALID_REQUEST);
AutoStateChanger changer(this, aNotify);
ClearPendingRequest(NS_BINDING_ABORTED, Some(OnNonvisible::DiscardImages));
ClearCurrentRequest(NS_BINDING_ABORTED, Some(OnNonvisible::DiscardImages));
}
Document* nsImageLoadingContent::GetOurOwnerDoc() {
return AsContent()->OwnerDoc();
}
Document* nsImageLoadingContent::GetOurCurrentDoc() {
return AsContent()->GetComposedDoc();
}
nsPresContext* nsImageLoadingContent::GetFramePresContext() {
nsIFrame* frame = GetOurPrimaryImageFrame();
if (!frame) {
return nullptr;
}
return frame->PresContext();
}
nsresult nsImageLoadingContent::StringToURI(const nsAString& aSpec,
Document* aDocument,
nsIURI** aURI) {
MOZ_ASSERT(aDocument, "Must have a document");
MOZ_ASSERT(aURI, "Null out param");
// (1) Get the base URI
nsIContent* thisContent = AsContent();
nsIURI* baseURL = thisContent->GetBaseURI();
// (2) Get the charset
auto encoding = aDocument->GetDocumentCharacterSet();
// (3) Construct the silly thing
return NS_NewURI(aURI, aSpec, encoding, baseURL);
}
nsresult nsImageLoadingContent::FireEvent(const nsAString& aEventType,
bool aIsCancelable) {
if (nsContentUtils::DocumentInactiveForImageLoads(GetOurOwnerDoc())) {
// Don't bother to fire any events, especially error events.
RejectDecodePromises(NS_ERROR_DOM_IMAGE_INACTIVE_DOCUMENT);
return NS_OK;
}
// We have to fire the event asynchronously so that we won't go into infinite
// loops in cases when onLoad handlers reset the src and the new src is in
// cache.
nsCOMPtr<nsINode> thisNode = AsContent();
RefPtr<AsyncEventDispatcher> loadBlockingAsyncDispatcher =
new LoadBlockingAsyncEventDispatcher(thisNode, aEventType, CanBubble::eNo,
ChromeOnlyDispatch::eNo);
loadBlockingAsyncDispatcher->PostDOMEvent();
if (aIsCancelable) {
mPendingEvent = loadBlockingAsyncDispatcher;
}
return NS_OK;
}
void nsImageLoadingContent::AsyncEventRunning(AsyncEventDispatcher* aEvent) {
if (mPendingEvent == aEvent) {
mPendingEvent = nullptr;
}
}
void nsImageLoadingContent::CancelPendingEvent() {
if (mPendingEvent) {
mPendingEvent->Cancel();
mPendingEvent = nullptr;
}
}
RefPtr<imgRequestProxy>& nsImageLoadingContent::PrepareNextRequest(
ImageLoadType aImageLoadType) {
MaybeForceSyncDecoding(/* aPrepareNextRequest */ true);
// We only want to cancel the existing current request if size is not
// available. bz says the web depends on this behavior.
// Otherwise, we get rid of any half-baked request that might be sitting there
// and make this one current.
return HaveSize(mCurrentRequest) ? PreparePendingRequest(aImageLoadType)
: PrepareCurrentRequest(aImageLoadType);
}
RefPtr<imgRequestProxy>& nsImageLoadingContent::PrepareCurrentRequest(
ImageLoadType aImageLoadType) {
// Get rid of anything that was there previously.
ClearCurrentRequest(NS_BINDING_ABORTED, Some(OnNonvisible::DiscardImages));
if (mNewRequestsWillNeedAnimationReset) {
mCurrentRequestFlags |= REQUEST_NEEDS_ANIMATION_RESET;
}
if (aImageLoadType == eImageLoadType_Imageset) {
mCurrentRequestFlags |= REQUEST_IS_IMAGESET;
}
// Return a reference.
return mCurrentRequest;
}
RefPtr<imgRequestProxy>& nsImageLoadingContent::PreparePendingRequest(
ImageLoadType aImageLoadType) {
// Get rid of anything that was there previously.
ClearPendingRequest(NS_BINDING_ABORTED, Some(OnNonvisible::DiscardImages));
if (mNewRequestsWillNeedAnimationReset) {
mPendingRequestFlags |= REQUEST_NEEDS_ANIMATION_RESET;
}
if (aImageLoadType == eImageLoadType_Imageset) {
mPendingRequestFlags |= REQUEST_IS_IMAGESET;
}
// Return a reference.
return mPendingRequest;
}
namespace {
class ImageRequestAutoLock {
public:
explicit ImageRequestAutoLock(imgIRequest* aRequest) : mRequest(aRequest) {
if (mRequest) {
mRequest->LockImage();
}
}
~ImageRequestAutoLock() {
if (mRequest) {
mRequest->UnlockImage();
}
}
private:
nsCOMPtr<imgIRequest> mRequest;
};
} // namespace
void nsImageLoadingContent::MakePendingRequestCurrent() {
MOZ_ASSERT(mPendingRequest);
// If we have a pending request, we know that there is an existing current
// request with size information. If the pending request is for a different
// URI, then we need to reject any outstanding promises.
nsCOMPtr<nsIURI> uri;
mPendingRequest->GetURI(getter_AddRefs(uri));
MaybeAgeRequestGeneration(uri);
// Lock mCurrentRequest for the duration of this method. We do this because
// PrepareCurrentRequest() might unlock mCurrentRequest. If mCurrentRequest
// and mPendingRequest are both requests for the same image, unlocking
// mCurrentRequest before we lock mPendingRequest can cause the lock count
// to go to 0 and the image to be discarded!
ImageRequestAutoLock autoLock(mCurrentRequest);
ImageLoadType loadType = (mPendingRequestFlags & REQUEST_IS_IMAGESET)
? eImageLoadType_Imageset
: eImageLoadType_Normal;
PrepareCurrentRequest(loadType) = mPendingRequest;
MakePendingScriptedRequestsCurrent();
mPendingRequest = nullptr;
mCurrentRequestFlags = mPendingRequestFlags;
mPendingRequestFlags = 0;
mCurrentRequestRegistered = mPendingRequestRegistered;
mPendingRequestRegistered = false;
ResetAnimationIfNeeded();
}
void nsImageLoadingContent::ClearCurrentRequest(
nsresult aReason, const Maybe<OnNonvisible>& aNonvisibleAction) {
if (!mCurrentRequest) {
// Even if we didn't have a current request, we might have been keeping
// a URI and flags as a placeholder for a failed load. Clear that now.
mCurrentURI = nullptr;
mCurrentRequestFlags = 0;
return;
}
MOZ_ASSERT(!mCurrentURI,
"Shouldn't have both mCurrentRequest and mCurrentURI!");
// Deregister this image from the refresh driver so it no longer receives
// notifications.
nsLayoutUtils::DeregisterImageRequest(GetFramePresContext(), mCurrentRequest,
&mCurrentRequestRegistered);
// Clean up the request.
UntrackImage(mCurrentRequest, aNonvisibleAction);
ClearScriptedRequests(CURRENT_REQUEST, aReason);
mCurrentRequest->CancelAndForgetObserver(aReason);
mCurrentRequest = nullptr;
mCurrentRequestFlags = 0;
}
void nsImageLoadingContent::ClearPendingRequest(
nsresult aReason, const Maybe<OnNonvisible>& aNonvisibleAction) {
if (!mPendingRequest) return;
// Deregister this image from the refresh driver so it no longer receives
// notifications.
nsLayoutUtils::DeregisterImageRequest(GetFramePresContext(), mPendingRequest,
&mPendingRequestRegistered);
UntrackImage(mPendingRequest, aNonvisibleAction);
ClearScriptedRequests(PENDING_REQUEST, aReason);
mPendingRequest->CancelAndForgetObserver(aReason);
mPendingRequest = nullptr;
mPendingRequestFlags = 0;
}
void nsImageLoadingContent::ResetAnimationIfNeeded() {
if (mCurrentRequest &&
(mCurrentRequestFlags & REQUEST_NEEDS_ANIMATION_RESET)) {
nsCOMPtr<imgIContainer> container;
mCurrentRequest->GetImage(getter_AddRefs(container));
if (container) container->ResetAnimation();
mCurrentRequestFlags &= ~REQUEST_NEEDS_ANIMATION_RESET;
}
}
bool nsImageLoadingContent::HaveSize(imgIRequest* aImage) {
// Handle the null case
if (!aImage) return false;
// Query the image
uint32_t status;
nsresult rv = aImage->GetImageStatus(&status);
return (NS_SUCCEEDED(rv) && (status & imgIRequest::STATUS_SIZE_AVAILABLE));
}
void nsImageLoadingContent::NotifyOwnerDocumentActivityChanged() {
if (!GetOurOwnerDoc()->IsCurrentActiveDocument()) {
RejectDecodePromises(NS_ERROR_DOM_IMAGE_INACTIVE_DOCUMENT);
}
}
void nsImageLoadingContent::BindToTree(BindContext& aContext,
nsINode& aParent) {
// We may be getting connected, if so our image should be tracked,
if (aContext.InComposedDoc()) {
TrackImage(mCurrentRequest);
TrackImage(mPendingRequest);
}
}
void nsImageLoadingContent::UnbindFromTree() {
// We may be leaving the document, so if our image is tracked, untrack it.
nsCOMPtr<Document> doc = GetOurCurrentDoc();
if (!doc) {
return;
}
UntrackImage(mCurrentRequest);
UntrackImage(mPendingRequest);
}
void nsImageLoadingContent::OnVisibilityChange(
Visibility aNewVisibility, const Maybe<OnNonvisible>& aNonvisibleAction) {
switch (aNewVisibility) {
case Visibility::ApproximatelyVisible:
TrackImage(mCurrentRequest);
TrackImage(mPendingRequest);
break;
case Visibility::ApproximatelyNonVisible:
UntrackImage(mCurrentRequest, aNonvisibleAction);
UntrackImage(mPendingRequest, aNonvisibleAction);
break;
case Visibility::Untracked:
MOZ_ASSERT_UNREACHABLE("Shouldn't notify for untracked visibility");
break;
}
}
void nsImageLoadingContent::TrackImage(imgIRequest* aImage,
nsIFrame* aFrame /*= nullptr */) {
if (!aImage) return;
MOZ_ASSERT(aImage == mCurrentRequest || aImage == mPendingRequest,
"Why haven't we heard of this request?");
Document* doc = GetOurCurrentDoc();
if (!doc) {
return;
}
if (!aFrame) {
aFrame = GetOurPrimaryImageFrame();
}
/* This line is deceptively simple. It hides a lot of subtlety. Before we
* create an nsImageFrame we call nsImageFrame::ShouldCreateImageFrameFor
* to determine if we should create an nsImageFrame or create a frame based
* on the display of the element (ie inline, block, etc). Inline, block, etc
* frames don't register for visibility tracking so they will return UNTRACKED
* from GetVisibility(). So this line is choosing to mark such images as
* visible. Once the image loads we will get an nsImageFrame and the proper
* visibility. This is a pitfall of tracking the visibility on the frames
* instead of the content node.
*/
if (!aFrame ||
aFrame->GetVisibility() == Visibility::ApproximatelyNonVisible) {
return;
}
if (aImage == mCurrentRequest &&
!(mCurrentRequestFlags & REQUEST_IS_TRACKED)) {
mCurrentRequestFlags |= REQUEST_IS_TRACKED;
doc->ImageTracker()->Add(mCurrentRequest);
}
if (aImage == mPendingRequest &&
!(mPendingRequestFlags & REQUEST_IS_TRACKED)) {
mPendingRequestFlags |= REQUEST_IS_TRACKED;
doc->ImageTracker()->Add(mPendingRequest);
}
}
void nsImageLoadingContent::UntrackImage(
imgIRequest* aImage, const Maybe<OnNonvisible>& aNonvisibleAction
/* = Nothing() */) {
if (!aImage) return;
MOZ_ASSERT(aImage == mCurrentRequest || aImage == mPendingRequest,
"Why haven't we heard of this request?");
// We may not be in the document. If we outlived our document that's fine,
// because the document empties out the tracker and unlocks all locked images
// on destruction. But if we were never in the document we may need to force
// discarding the image here, since this is the only chance we have.
Document* doc = GetOurCurrentDoc();
if (aImage == mCurrentRequest) {
if (doc && (mCurrentRequestFlags & REQUEST_IS_TRACKED)) {
mCurrentRequestFlags &= ~REQUEST_IS_TRACKED;
doc->ImageTracker()->Remove(
mCurrentRequest,
aNonvisibleAction == Some(OnNonvisible::DiscardImages)
? ImageTracker::REQUEST_DISCARD
: 0);
} else if (aNonvisibleAction == Some(OnNonvisible::DiscardImages)) {
// If we're not in the document we may still need to be discarded.
aImage->RequestDiscard();
}
}
if (aImage == mPendingRequest) {
if (doc && (mPendingRequestFlags & REQUEST_IS_TRACKED)) {
mPendingRequestFlags &= ~REQUEST_IS_TRACKED;
doc->ImageTracker()->Remove(
mPendingRequest,
aNonvisibleAction == Some(OnNonvisible::DiscardImages)
? ImageTracker::REQUEST_DISCARD
: 0);
} else if (aNonvisibleAction == Some(OnNonvisible::DiscardImages)) {
// If we're not in the document we may still need to be discarded.
aImage->RequestDiscard();
}
}
}
CORSMode nsImageLoadingContent::GetCORSMode() { return CORS_NONE; }
nsImageLoadingContent::ImageObserver::ImageObserver(
imgINotificationObserver* aObserver)
: mObserver(aObserver), mNext(nullptr) {
MOZ_COUNT_CTOR(ImageObserver);
}
nsImageLoadingContent::ImageObserver::~ImageObserver() {
MOZ_COUNT_DTOR(ImageObserver);
NS_CONTENT_DELETE_LIST_MEMBER(ImageObserver, this, mNext);
}
nsImageLoadingContent::ScriptedImageObserver::ScriptedImageObserver(
imgINotificationObserver* aObserver,
RefPtr<imgRequestProxy>&& aCurrentRequest,
RefPtr<imgRequestProxy>&& aPendingRequest)
: mObserver(aObserver),
mCurrentRequest(aCurrentRequest),
mPendingRequest(aPendingRequest) {}
nsImageLoadingContent::ScriptedImageObserver::~ScriptedImageObserver() {
// We should have cancelled any requests before getting released.
DebugOnly<bool> cancel = CancelRequests();
MOZ_ASSERT(!cancel, "Still have requests in ~ScriptedImageObserver!");
}
bool nsImageLoadingContent::ScriptedImageObserver::CancelRequests() {
bool cancelled = false;
if (mCurrentRequest) {
mCurrentRequest->CancelAndForgetObserver(NS_BINDING_ABORTED);
mCurrentRequest = nullptr;
cancelled = true;
}
if (mPendingRequest) {
mPendingRequest->CancelAndForgetObserver(NS_BINDING_ABORTED);
mPendingRequest = nullptr;
cancelled = true;
}
return cancelled;
}
Element* nsImageLoadingContent::FindImageMap() {
return FindImageMap(AsContent()->AsElement());
}
/* static */ Element* nsImageLoadingContent::FindImageMap(Element* aElement) {
nsAutoString useMap;
aElement->GetAttr(nsGkAtoms::usemap, useMap);
if (useMap.IsEmpty()) {
return nullptr;
}
nsAString::const_iterator start, end;
useMap.BeginReading(start);
useMap.EndReading(end);
int32_t hash = useMap.FindChar('#');
if (hash < 0) {
return nullptr;
}
// useMap contains a '#', set start to point right after the '#'
start.advance(hash + 1);
if (start == end) {
return nullptr; // useMap == "#"
}
RefPtr<nsContentList> imageMapList;
if (aElement->IsInUncomposedDoc()) {
// Optimize the common case and use document level image map.
imageMapList = aElement->OwnerDoc()->ImageMapList();
} else {
// Per HTML spec image map should be searched in the element's scope,
// so using SubtreeRoot() here.
// Because this is a temporary list, we don't need to make it live.
imageMapList =
new nsContentList(aElement->SubtreeRoot(), kNameSpaceID_XHTML,
nsGkAtoms::map, nsGkAtoms::map, true, /* deep */
false /* live */);
}
nsAutoString mapName(Substring(start, end));
uint32_t i, n = imageMapList->Length(true);
for (i = 0; i < n; ++i) {
nsIContent* map = imageMapList->Item(i);
if (map->AsElement()->AttrValueIs(kNameSpaceID_None, nsGkAtoms::id, mapName,
eCaseMatters) ||
map->AsElement()->AttrValueIs(kNameSpaceID_None, nsGkAtoms::name,
mapName, eCaseMatters)) {
return map->AsElement();
}
}
return nullptr;
}
nsLoadFlags nsImageLoadingContent::LoadFlags() {
auto* image = HTMLImageElement::FromNode(AsContent());
if (image && image->OwnerDoc()->IsScriptEnabled() &&
!image->OwnerDoc()->IsStaticDocument() &&
image->LoadingState() == Element::Loading::Lazy) {
// Note that LOAD_BACKGROUND is not about priority of the load, but about
// whether it blocks the load event (by bypassing the loadgroup).
return nsIRequest::LOAD_BACKGROUND;
}
return nsIRequest::LOAD_NORMAL;
}
FetchPriority nsImageLoadingContent::GetFetchPriorityForImage() const {
return FetchPriority::Auto;
}