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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
#include "mozilla/dom/HTMLImageElement.h"
#include "mozilla/PresShell.h"
#include "mozilla/dom/BindContext.h"
#include "mozilla/dom/BindingUtils.h"
#include "mozilla/dom/HTMLImageElementBinding.h"
#include "mozilla/dom/NameSpaceConstants.h"
#include "mozilla/dom/UnbindContext.h"
#include "nsGenericHTMLElement.h"
#include "nsGkAtoms.h"
#include "nsPresContext.h"
#include "nsSize.h"
#include "mozilla/dom/Document.h"
#include "nsImageFrame.h"
#include "nsContentUtils.h"
#include "nsContainerFrame.h"
#include "nsNodeInfoManager.h"
#include "mozilla/MouseEvents.h"
#include "nsFocusManager.h"
#include "mozilla/dom/DOMIntersectionObserver.h"
#include "mozilla/dom/HTMLFormElement.h"
#include "mozilla/dom/MutationEventBinding.h"
#include "mozilla/dom/UserActivation.h"
#include "nsAttrValueOrString.h"
#include "imgLoader.h"
// Responsive images!
#include "mozilla/dom/HTMLSourceElement.h"
#include "mozilla/dom/ResponsiveImageSelector.h"
#include "imgINotificationObserver.h"
#include "imgRequestProxy.h"
#include "mozilla/CycleCollectedJSContext.h"
#include "mozilla/EventDispatcher.h"
#include "mozilla/MappedDeclarationsBuilder.h"
#include "mozilla/Maybe.h"
#include "mozilla/RestyleManager.h"
#include "nsLayoutUtils.h"
using namespace mozilla::net;
using mozilla::Maybe;
NS_IMPL_NS_NEW_HTML_ELEMENT(Image)
#ifdef DEBUG
// Is aSubject a previous sibling of aNode.
static bool IsPreviousSibling(const nsINode* aSubject, const nsINode* aNode) {
if (aSubject == aNode) {
return false;
}
nsINode* parent = aSubject->GetParentNode();
if (parent && parent == aNode->GetParentNode()) {
const Maybe<uint32_t> indexOfSubject = parent->ComputeIndexOf(aSubject);
const Maybe<uint32_t> indexOfNode = parent->ComputeIndexOf(aNode);
if (MOZ_LIKELY(indexOfSubject.isSome() && indexOfNode.isSome())) {
return *indexOfSubject < *indexOfNode;
}
// XXX Keep the odd traditional behavior for now.
return indexOfSubject.isNothing() && indexOfNode.isSome();
}
return false;
}
#endif
namespace mozilla::dom {
// Calls LoadSelectedImage on host element unless it has been superseded or
// canceled -- this is the synchronous section of "update the image data".
class ImageLoadTask final : public MicroTaskRunnable {
public:
ImageLoadTask(HTMLImageElement* aElement, bool aAlwaysLoad,
bool aUseUrgentStartForChannel)
: mElement(aElement),
mAlwaysLoad(aAlwaysLoad),
mUseUrgentStartForChannel(aUseUrgentStartForChannel) {
mDocument = aElement->OwnerDoc();
mDocument->BlockOnload();
}
void Run(AutoSlowOperation& aAso) override {
if (mElement->mPendingImageLoadTask == this) {
mElement->mPendingImageLoadTask = nullptr;
mElement->mUseUrgentStartForChannel = mUseUrgentStartForChannel;
mElement->LoadSelectedImage(true, true, mAlwaysLoad);
}
mDocument->UnblockOnload(false);
}
bool Suppressed() override {
nsIGlobalObject* global = mElement->GetOwnerGlobal();
return global && global->IsInSyncOperation();
}
bool AlwaysLoad() const { return mAlwaysLoad; }
private:
~ImageLoadTask() = default;
RefPtr<HTMLImageElement> mElement;
nsCOMPtr<Document> mDocument;
bool mAlwaysLoad;
// True if we want to set nsIClassOfService::UrgentStart to the channel to
// get the response ASAP for better user responsiveness.
bool mUseUrgentStartForChannel;
};
HTMLImageElement::HTMLImageElement(
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
: nsGenericHTMLElement(std::move(aNodeInfo)) {
// We start out broken
AddStatesSilently(ElementState::BROKEN);
}
HTMLImageElement::~HTMLImageElement() { nsImageLoadingContent::Destroy(); }
NS_IMPL_CYCLE_COLLECTION_INHERITED(HTMLImageElement, nsGenericHTMLElement,
mResponsiveSelector)
NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED(HTMLImageElement,
nsGenericHTMLElement,
nsIImageLoadingContent,
imgINotificationObserver)
NS_IMPL_ELEMENT_CLONE(HTMLImageElement)
bool HTMLImageElement::IsInteractiveHTMLContent() const {
return HasAttr(nsGkAtoms::usemap) ||
nsGenericHTMLElement::IsInteractiveHTMLContent();
}
void HTMLImageElement::AsyncEventRunning(AsyncEventDispatcher* aEvent) {
nsImageLoadingContent::AsyncEventRunning(aEvent);
}
void HTMLImageElement::GetCurrentSrc(nsAString& aValue) {
nsCOMPtr<nsIURI> currentURI;
GetCurrentURI(getter_AddRefs(currentURI));
if (currentURI) {
nsAutoCString spec;
currentURI->GetSpec(spec);
CopyUTF8toUTF16(spec, aValue);
} else {
SetDOMStringToNull(aValue);
}
}
bool HTMLImageElement::Draggable() const {
// images may be dragged unless the draggable attribute is false
return !AttrValueIs(kNameSpaceID_None, nsGkAtoms::draggable,
nsGkAtoms::_false, eIgnoreCase);
}
bool HTMLImageElement::Complete() {
// It is still not clear what value should img.complete return in various
if (!HasAttr(nsGkAtoms::srcset) && !HasNonEmptyAttr(nsGkAtoms::src)) {
return true;
}
if (!mCurrentRequest || mPendingRequest) {
return false;
}
uint32_t status;
mCurrentRequest->GetImageStatus(&status);
return (status &
(imgIRequest::STATUS_LOAD_COMPLETE | imgIRequest::STATUS_ERROR)) != 0;
}
CSSIntPoint HTMLImageElement::GetXY() {
nsIFrame* frame = GetPrimaryFrame(FlushType::Layout);
if (!frame) {
return CSSIntPoint(0, 0);
}
return CSSIntPoint::FromAppUnitsRounded(
frame->GetOffsetTo(frame->PresShell()->GetRootFrame()));
}
int32_t HTMLImageElement::X() { return GetXY().x; }
int32_t HTMLImageElement::Y() { return GetXY().y; }
void HTMLImageElement::GetDecoding(nsAString& aValue) {
GetEnumAttr(nsGkAtoms::decoding, kDecodingTableDefault->tag, aValue);
}
already_AddRefed<Promise> HTMLImageElement::Decode(ErrorResult& aRv) {
return nsImageLoadingContent::QueueDecodeAsync(aRv);
}
bool HTMLImageElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
const nsAString& aValue,
nsIPrincipal* aMaybeScriptedPrincipal,
nsAttrValue& aResult) {
if (aNamespaceID == kNameSpaceID_None) {
if (aAttribute == nsGkAtoms::align) {
return ParseAlignValue(aValue, aResult);
}
if (aAttribute == nsGkAtoms::crossorigin) {
ParseCORSValue(aValue, aResult);
return true;
}
if (aAttribute == nsGkAtoms::decoding) {
return aResult.ParseEnumValue(aValue, kDecodingTable,
/* aCaseSensitive = */ false,
kDecodingTableDefault);
}
if (aAttribute == nsGkAtoms::loading) {
return ParseLoadingAttribute(aValue, aResult);
}
if (aAttribute == nsGkAtoms::fetchpriority) {
ParseFetchPriority(aValue, aResult);
return true;
}
if (ParseImageAttribute(aAttribute, aValue, aResult)) {
return true;
}
}
return nsGenericHTMLElement::ParseAttribute(aNamespaceID, aAttribute, aValue,
aMaybeScriptedPrincipal, aResult);
}
void HTMLImageElement::MapAttributesIntoRule(
MappedDeclarationsBuilder& aBuilder) {
MapImageAlignAttributeInto(aBuilder);
MapImageBorderAttributeInto(aBuilder);
MapImageMarginAttributeInto(aBuilder);
MapImageSizeAttributesInto(aBuilder, MapAspectRatio::Yes);
MapCommonAttributesInto(aBuilder);
}
nsChangeHint HTMLImageElement::GetAttributeChangeHint(const nsAtom* aAttribute,
int32_t aModType) const {
nsChangeHint retval =
nsGenericHTMLElement::GetAttributeChangeHint(aAttribute, aModType);
if (aAttribute == nsGkAtoms::usemap || aAttribute == nsGkAtoms::ismap) {
retval |= nsChangeHint_ReconstructFrame;
} else if (aAttribute == nsGkAtoms::alt) {
if (aModType == MutationEvent_Binding::ADDITION ||
aModType == MutationEvent_Binding::REMOVAL) {
retval |= nsChangeHint_ReconstructFrame;
}
}
return retval;
}
NS_IMETHODIMP_(bool)
HTMLImageElement::IsAttributeMapped(const nsAtom* aAttribute) const {
static const MappedAttributeEntry* const map[] = {
sCommonAttributeMap, sImageMarginSizeAttributeMap,
sImageBorderAttributeMap, sImageAlignAttributeMap};
return FindAttributeDependence(aAttribute, map);
}
nsMapRuleToAttributesFunc HTMLImageElement::GetAttributeMappingFunction()
const {
return &MapAttributesIntoRule;
}
void HTMLImageElement::BeforeSetAttr(int32_t aNameSpaceID, nsAtom* aName,
const nsAttrValue* aValue, bool aNotify) {
if (aNameSpaceID == kNameSpaceID_None && mForm &&
(aName == nsGkAtoms::name || aName == nsGkAtoms::id)) {
// remove the image from the hashtable as needed
if (const auto* old = GetParsedAttr(aName); old && !old->IsEmptyString()) {
mForm->RemoveImageElementFromTable(
this, nsDependentAtomString(old->GetAtomValue()));
}
}
return nsGenericHTMLElement::BeforeSetAttr(aNameSpaceID, aName, aValue,
aNotify);
}
void HTMLImageElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
const nsAttrValue* aValue,
const nsAttrValue* aOldValue,
nsIPrincipal* aMaybeScriptedPrincipal,
bool aNotify) {
if (aNameSpaceID != kNameSpaceID_None) {
return nsGenericHTMLElement::AfterSetAttr(aNameSpaceID, aName, aValue,
aOldValue,
aMaybeScriptedPrincipal, aNotify);
}
nsAttrValueOrString attrVal(aValue);
if (aName == nsGkAtoms::src) {
mSrcURI = nullptr;
if (aValue && !aValue->IsEmptyString()) {
StringToURI(attrVal.String(), OwnerDoc(), getter_AddRefs(mSrcURI));
}
}
if (aValue) {
AfterMaybeChangeAttr(aNameSpaceID, aName, attrVal, aOldValue,
aMaybeScriptedPrincipal, aNotify);
}
if (mForm && (aName == nsGkAtoms::name || aName == nsGkAtoms::id) && aValue &&
!aValue->IsEmptyString()) {
// add the image to the hashtable as needed
MOZ_ASSERT(aValue->Type() == nsAttrValue::eAtom,
"Expected atom value for name/id");
mForm->AddImageElementToTable(
this, nsDependentAtomString(aValue->GetAtomValue()));
}
bool forceReload = false;
if (aName == nsGkAtoms::loading && !mLoading) {
if (aValue && Loading(aValue->GetEnumValue()) == Loading::Lazy) {
SetLazyLoading();
} else if (aOldValue &&
Loading(aOldValue->GetEnumValue()) == Loading::Lazy) {
StopLazyLoading(StartLoading::Yes);
}
} else if (aName == nsGkAtoms::src && !aValue) {
// NOTE: regular src value changes are handled in AfterMaybeChangeAttr, so
// this only needs to handle unsetting the src attribute.
// Mark channel as urgent-start before load image if the image load is
// initaiated by a user interaction.
mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
// AfterMaybeChangeAttr handles setting src since it needs to catch
// img.src = img.src, so we only need to handle the unset case
if (InResponsiveMode()) {
if (mResponsiveSelector && mResponsiveSelector->Content() == this) {
mResponsiveSelector->SetDefaultSource(VoidString());
}
UpdateSourceSyncAndQueueImageTask(true);
} else {
CancelImageRequests(aNotify);
}
} else if (aName == nsGkAtoms::srcset) {
// Mark channel as urgent-start before load image if the image load is
// initaiated by a user interaction.
mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
mSrcsetTriggeringPrincipal = aMaybeScriptedPrincipal;
PictureSourceSrcsetChanged(this, attrVal.String(), aNotify);
} else if (aName == nsGkAtoms::sizes) {
// Mark channel as urgent-start before load image if the image load is
// initiated by a user interaction.
mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
PictureSourceSizesChanged(this, attrVal.String(), aNotify);
} else if (aName == nsGkAtoms::decoding) {
// Request sync or async image decoding.
SetSyncDecodingHint(
aValue && static_cast<ImageDecodingType>(aValue->GetEnumValue()) ==
ImageDecodingType::Sync);
} else if (aName == nsGkAtoms::referrerpolicy) {
ReferrerPolicy referrerPolicy = GetReferrerPolicyAsEnum();
// FIXME(emilio): Why only when not in responsive mode? Also see below for
// aNotify.
forceReload = aNotify && !InResponsiveMode() &&
referrerPolicy != ReferrerPolicy::_empty &&
referrerPolicy != ReferrerPolicyFromAttr(aOldValue);
} else if (aName == nsGkAtoms::crossorigin) {
// FIXME(emilio): The aNotify bit seems a bit suspicious, but it is useful
// to avoid extra sync loads, specially in non-responsive mode. Ideally we
// simplify this a bit.
forceReload = aNotify && GetCORSMode() != AttrValueToCORSMode(aOldValue);
}
if (forceReload) {
// Because we load image synchronously in non-responsive-mode, we need to do
// reload after the attribute has been set if the reload is triggered by
// cross origin / referrer policy changing.
//
// Mark channel as urgent-start before load image if the image load is
// initiated by a user interaction.
mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
if (InResponsiveMode()) {
// Per spec, full selection runs when this changes, even though
// it doesn't directly affect the source selection
UpdateSourceSyncAndQueueImageTask(true);
} else if (ShouldLoadImage()) {
// non-responsive mode. Force a new load of the image with the
// new cross origin policy
ForceReload(aNotify, IgnoreErrors());
}
}
return nsGenericHTMLElement::AfterSetAttr(
aNameSpaceID, aName, aValue, aOldValue, aMaybeScriptedPrincipal, aNotify);
}
void HTMLImageElement::OnAttrSetButNotChanged(int32_t aNamespaceID,
nsAtom* aName,
const nsAttrValueOrString& aValue,
bool aNotify) {
AfterMaybeChangeAttr(aNamespaceID, aName, aValue, nullptr, nullptr, aNotify);
return nsGenericHTMLElement::OnAttrSetButNotChanged(aNamespaceID, aName,
aValue, aNotify);
}
void HTMLImageElement::AfterMaybeChangeAttr(
int32_t aNamespaceID, nsAtom* aName, const nsAttrValueOrString& aValue,
const nsAttrValue* aOldValue, nsIPrincipal* aMaybeScriptedPrincipal,
bool aNotify) {
if (aNamespaceID != kNameSpaceID_None || aName != nsGkAtoms::src) {
return;
}
// We need to force our image to reload. This must be done here, not in
// AfterSetAttr or BeforeSetAttr, because we want to do it even if the attr is
// being set to its existing value, which is normally optimized away as a
// no-op.
//
// If we are in responsive mode, we drop the forced reload behavior,
// but still trigger a image load task for img.src = img.src per
// spec.
//
// Both cases handle unsetting src in AfterSetAttr
// Mark channel as urgent-start before load image if the image load is
// initaiated by a user interaction.
mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
mSrcTriggeringPrincipal = nsContentUtils::GetAttrTriggeringPrincipal(
this, aValue.String(), aMaybeScriptedPrincipal);
if (InResponsiveMode()) {
if (mResponsiveSelector && mResponsiveSelector->Content() == this) {
mResponsiveSelector->SetDefaultSource(mSrcURI, mSrcTriggeringPrincipal);
}
UpdateSourceSyncAndQueueImageTask(true);
} else if (aNotify && ShouldLoadImage()) {
// If aNotify is false, we are coming from the parser or some such place;
// we'll get bound after all the attributes have been set, so we'll do the
// sync image load from BindToTree. Skip the LoadImage call in that case.
// Note that this sync behavior is partially removed from the spec, bug
// 1076583
mNewRequestsWillNeedAnimationReset = true;
// Force image loading here, so that we'll try to load the image from
// network if it's set to be not cacheable.
// Potentially, false could be passed here rather than aNotify since
// UpdateState will be called by SetAttrAndNotify, but there are two
// obstacles to this: 1) LoadImage will end up calling
// UpdateState(aNotify), and we do not want it to call UpdateState(false)
// when aNotify is true, and 2) When this function is called by
// OnAttrSetButNotChanged, SetAttrAndNotify will not subsequently call
// UpdateState.
LoadSelectedImage(/* aForce = */ true, aNotify,
/* aAlwaysLoad = */ true);
mNewRequestsWillNeedAnimationReset = false;
}
}
void HTMLImageElement::GetEventTargetParent(EventChainPreVisitor& aVisitor) {
// We handle image element with attribute ismap in its corresponding frame
// element. Set mMultipleActionsPrevented here to prevent the click event
// trigger the behaviors in Element::PostHandleEventForLinks
WidgetMouseEvent* mouseEvent = aVisitor.mEvent->AsMouseEvent();
if (mouseEvent && mouseEvent->IsLeftClickEvent() && IsMap()) {
mouseEvent->mFlags.mMultipleActionsPrevented = true;
}
nsGenericHTMLElement::GetEventTargetParent(aVisitor);
}
nsINode* HTMLImageElement::GetScopeChainParent() const {
if (mForm) {
return mForm;
}
return nsGenericHTMLElement::GetScopeChainParent();
}
bool HTMLImageElement::IsHTMLFocusable(bool aWithMouse, bool* aIsFocusable,
int32_t* aTabIndex) {
int32_t tabIndex = TabIndex();
if (IsInComposedDoc() && FindImageMap()) {
// Use tab index on individual map areas.
*aTabIndex = (sTabFocusModel & eTabFocus_linksMask) ? 0 : -1;
// Image map is not focusable itself, but flag as tabbable
// so that image map areas get walked into.
*aIsFocusable = false;
return false;
}
// Can be in tab order if tabindex >=0 and form controls are tabbable.
*aTabIndex = (sTabFocusModel & eTabFocus_formElementsMask) ? tabIndex : -1;
*aIsFocusable = IsFormControlDefaultFocusable(aWithMouse) &&
(tabIndex >= 0 || GetTabIndexAttrValue().isSome());
return false;
}
nsresult HTMLImageElement::BindToTree(BindContext& aContext, nsINode& aParent) {
nsresult rv = nsGenericHTMLElement::BindToTree(aContext, aParent);
NS_ENSURE_SUCCESS(rv, rv);
nsImageLoadingContent::BindToTree(aContext, aParent);
UpdateFormOwner();
if (HaveSrcsetOrInPicture()) {
if (IsInComposedDoc() && !mInDocResponsiveContent) {
aContext.OwnerDoc().AddResponsiveContent(this);
mInDocResponsiveContent = true;
}
// Mark channel as urgent-start before load image if the image load is
// initaiated by a user interaction.
mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
// Run selection algorithm when an img element is inserted into a document
// in order to react to changes in the environment. See note of
//
// We also do this in PictureSourceAdded() if it is in <picture>, so here
// we only need to do if its parent is not <picture>, even if there is no
// <source>.
if (!IsInPicture()) {
UpdateSourceSyncAndQueueImageTask(false);
}
} else if (!InResponsiveMode() && HasAttr(nsGkAtoms::src)) {
// We skip loading when our attributes were set from parser land,
// so trigger a aForce=false load now to check if things changed.
// This isn't necessary for responsive mode, since creating the
// image load task is asynchronous we don't need to take special
// care to avoid doing so when being filled by the parser.
// Mark channel as urgent-start before load image if the image load is
// initaiated by a user interaction.
mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
// We still act synchronously for the non-responsive case (Bug
// 1076583), but still need to delay if it is unsafe to run
// script.
// If loading is temporarily disabled, don't even launch MaybeLoadImage.
// Otherwise MaybeLoadImage may run later when someone has reenabled
// loading.
if (LoadingEnabled() && ShouldLoadImage()) {
nsContentUtils::AddScriptRunner(
NewRunnableMethod<bool>("dom::HTMLImageElement::MaybeLoadImage", this,
&HTMLImageElement::MaybeLoadImage, false));
}
}
return rv;
}
void HTMLImageElement::UnbindFromTree(UnbindContext& aContext) {
if (mForm) {
if (aContext.IsUnbindRoot(this) || !FindAncestorForm(mForm)) {
ClearForm(true);
} else {
UnsetFlags(MAYBE_ORPHAN_FORM_ELEMENT);
}
}
if (mInDocResponsiveContent) {
OwnerDoc()->RemoveResponsiveContent(this);
mInDocResponsiveContent = false;
}
nsImageLoadingContent::UnbindFromTree();
nsGenericHTMLElement::UnbindFromTree(aContext);
}
void HTMLImageElement::UpdateFormOwner() {
if (!mForm) {
mForm = FindAncestorForm();
}
if (mForm && !HasFlag(ADDED_TO_FORM)) {
// Now we need to add ourselves to the form
nsAutoString nameVal, idVal;
GetAttr(nsGkAtoms::name, nameVal);
GetAttr(nsGkAtoms::id, idVal);
SetFlags(ADDED_TO_FORM);
mForm->AddImageElement(this);
if (!nameVal.IsEmpty()) {
mForm->AddImageElementToTable(this, nameVal);
}
if (!idVal.IsEmpty()) {
mForm->AddImageElementToTable(this, idVal);
}
}
}
void HTMLImageElement::MaybeLoadImage(bool aAlwaysForceLoad) {
// Our base URI may have changed, or we may have had responsive parameters
// change while not bound to the tree. However, at this moment, we should have
// updated the responsive source in other places, so we don't have to re-parse
// src/srcset here. Just need to LoadImage.
// Note, check LoadingEnabled() after LoadImage call.
LoadSelectedImage(aAlwaysForceLoad, /* aNotify */ true, aAlwaysForceLoad);
if (!LoadingEnabled()) {
CancelImageRequests(true);
}
}
void HTMLImageElement::NodeInfoChanged(Document* aOldDoc) {
nsGenericHTMLElement::NodeInfoChanged(aOldDoc);
// Reparse the URI if needed. Note that we can't check whether we already have
// a parsed URI, because it might be null even if we have a valid src
// attribute, if we tried to parse with a different base.
mSrcURI = nullptr;
nsAutoString src;
if (GetAttr(nsGkAtoms::src, src) && !src.IsEmpty()) {
StringToURI(src, OwnerDoc(), getter_AddRefs(mSrcURI));
}
if (mLazyLoading) {
aOldDoc->GetLazyLoadObserver()->Unobserve(*this);
mLazyLoading = false;
SetLazyLoading();
}
// Run selection algorithm synchronously when an img element's adopting steps
// are run, in order to react to changes in the environment, per spec,
// and
if (InResponsiveMode()) {
UpdateResponsiveSource();
}
// Force reload image if adoption steps are run.
// If loading is temporarily disabled, don't even launch script runner.
// Otherwise script runner may run later when someone has reenabled loading.
StartLoadingIfNeeded();
}
// static
already_AddRefed<HTMLImageElement> HTMLImageElement::Image(
const GlobalObject& aGlobal, const Optional<uint32_t>& aWidth,
const Optional<uint32_t>& aHeight, ErrorResult& aError) {
nsCOMPtr<nsPIDOMWindowInner> win = do_QueryInterface(aGlobal.GetAsSupports());
Document* doc;
if (!win || !(doc = win->GetExtantDoc())) {
aError.Throw(NS_ERROR_FAILURE);
return nullptr;
}
RefPtr<mozilla::dom::NodeInfo> nodeInfo = doc->NodeInfoManager()->GetNodeInfo(
nsGkAtoms::img, nullptr, kNameSpaceID_XHTML, ELEMENT_NODE);
auto* nim = nodeInfo->NodeInfoManager();
RefPtr<HTMLImageElement> img = new (nim) HTMLImageElement(nodeInfo.forget());
if (aWidth.WasPassed()) {
img->SetWidth(aWidth.Value(), aError);
if (aError.Failed()) {
return nullptr;
}
if (aHeight.WasPassed()) {
img->SetHeight(aHeight.Value(), aError);
if (aError.Failed()) {
return nullptr;
}
}
}
return img.forget();
}
uint32_t HTMLImageElement::Height() { return GetWidthHeightForImage().height; }
uint32_t HTMLImageElement::Width() { return GetWidthHeightForImage().width; }
nsIntSize HTMLImageElement::NaturalSize() {
if (!mCurrentRequest) {
return {};
}
nsCOMPtr<imgIContainer> image;
mCurrentRequest->GetImage(getter_AddRefs(image));
if (!image) {
return {};
}
nsIntSize size;
Unused << image->GetHeight(&size.height);
Unused << image->GetWidth(&size.width);
ImageResolution resolution = image->GetResolution();
// NOTE(emilio): What we implement here matches the image-set() spec, but it's
// unclear whether this is the right thing to do, see
if (mResponsiveSelector) {
float density = mResponsiveSelector->GetSelectedImageDensity();
MOZ_ASSERT(density >= 0.0);
resolution.ScaleBy(density);
}
resolution.ApplyTo(size.width, size.height);
return size;
}
nsresult HTMLImageElement::CopyInnerTo(HTMLImageElement* aDest) {
nsresult rv = nsGenericHTMLElement::CopyInnerTo(aDest);
if (NS_FAILED(rv)) {
return rv;
}
// In SetAttr (called from nsGenericHTMLElement::CopyInnerTo), aDest skipped
// doing the image load because we passed in false for aNotify. But we
// really do want it to do the load, so set it up to happen once the cloning
// reaches a stable state.
if (!aDest->InResponsiveMode() && aDest->HasAttr(nsGkAtoms::src) &&
aDest->ShouldLoadImage()) {
// Mark channel as urgent-start before load image if the image load is
// initaiated by a user interaction.
mUseUrgentStartForChannel = UserActivation::IsHandlingUserInput();
nsContentUtils::AddScriptRunner(
NewRunnableMethod<bool>("dom::HTMLImageElement::MaybeLoadImage", aDest,
&HTMLImageElement::MaybeLoadImage, false));
}
return NS_OK;
}
CORSMode HTMLImageElement::GetCORSMode() {
return AttrValueToCORSMode(GetParsedAttr(nsGkAtoms::crossorigin));
}
JSObject* HTMLImageElement::WrapNode(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return HTMLImageElement_Binding::Wrap(aCx, this, aGivenProto);
}
#ifdef DEBUG
HTMLFormElement* HTMLImageElement::GetForm() const { return mForm; }
#endif
void HTMLImageElement::SetForm(HTMLFormElement* aForm) {
MOZ_ASSERT(aForm, "Don't pass null here");
NS_ASSERTION(!mForm,
"We don't support switching from one non-null form to another.");
mForm = aForm;
}
void HTMLImageElement::ClearForm(bool aRemoveFromForm) {
NS_ASSERTION((mForm != nullptr) == HasFlag(ADDED_TO_FORM),
"Form control should have had flag set correctly");
if (!mForm) {
return;
}
if (aRemoveFromForm) {
nsAutoString nameVal, idVal;
GetAttr(nsGkAtoms::name, nameVal);
GetAttr(nsGkAtoms::id, idVal);
mForm->RemoveImageElement(this);
if (!nameVal.IsEmpty()) {
mForm->RemoveImageElementFromTable(this, nameVal);
}
if (!idVal.IsEmpty()) {
mForm->RemoveImageElementFromTable(this, idVal);
}
}
UnsetFlags(ADDED_TO_FORM);
mForm = nullptr;
}
void HTMLImageElement::UpdateSourceSyncAndQueueImageTask(
bool aAlwaysLoad, const HTMLSourceElement* aSkippedSource) {
// Per spec, when updating the image data or reacting to environment
// changes, we always run the full selection (including selecting the source
// element and the best fit image from srcset) even if it doesn't directly
// affect the source selection.
//
// However, in the spec of updating the image data, the selection of image
// source URL is in the asynchronous part (i.e. in a microtask), and so this
// doesn't guarantee that the image style is correct after we flush the style
// synchornously. So here we update the responsive source synchronously always
// to make sure the image source is always up-to-date after each DOM mutation.
const bool changed = UpdateResponsiveSource(aSkippedSource);
// If loading is temporarily disabled, we don't want to queue tasks
// that may then run when loading is re-enabled.
if (!LoadingEnabled() || !ShouldLoadImage()) {
return;
}
// Ensure that we don't overwrite a previous load request that requires
// a complete load to occur.
bool alwaysLoad = aAlwaysLoad;
if (mPendingImageLoadTask) {
alwaysLoad = alwaysLoad || mPendingImageLoadTask->AlwaysLoad();
}
if (!changed && !alwaysLoad) {
return;
}
QueueImageLoadTask(alwaysLoad);
}
bool HTMLImageElement::HaveSrcsetOrInPicture() {
if (HasAttr(nsGkAtoms::srcset)) {
return true;
}
return IsInPicture();
}
bool HTMLImageElement::InResponsiveMode() {
// When we lose srcset or leave a <picture> element, the fallback to img.src
// will happen from the microtask, and we should behave responsively in the
// interim
return mResponsiveSelector || mPendingImageLoadTask ||
HaveSrcsetOrInPicture();
}
bool HTMLImageElement::SelectedSourceMatchesLast(nsIURI* aSelectedSource) {
// If there was no selected source previously, we don't want to short-circuit
// the load. Similarly for if there is no newly selected source.
if (!mLastSelectedSource || !aSelectedSource) {
return false;
}
bool equal = false;
return NS_SUCCEEDED(mLastSelectedSource->Equals(aSelectedSource, &equal)) &&
equal;
}
nsresult HTMLImageElement::LoadSelectedImage(bool aForce, bool aNotify,
bool aAlwaysLoad) {
// In responsive mode, we have to make sure we ran the full selection algrithm
// before loading the selected image.
// Use this assertion to catch any cases we missed.
MOZ_ASSERT(!UpdateResponsiveSource(),
"The image source should be the same because we update the "
"responsive source synchronously");
// The density is default to 1.0 for the src attribute case.
double currentDensity = mResponsiveSelector
? mResponsiveSelector->GetSelectedImageDensity()
: 1.0;
nsCOMPtr<nsIURI> selectedSource;
nsCOMPtr<nsIPrincipal> triggeringPrincipal;
ImageLoadType type = eImageLoadType_Normal;
bool hasSrc = false;
if (mResponsiveSelector) {
selectedSource = mResponsiveSelector->GetSelectedImageURL();
triggeringPrincipal =
mResponsiveSelector->GetSelectedImageTriggeringPrincipal();
type = eImageLoadType_Imageset;
} else if (mSrcURI || HasAttr(nsGkAtoms::src)) {
hasSrc = true;
if (mSrcURI) {
selectedSource = mSrcURI;
if (HaveSrcsetOrInPicture()) {
// If we have a srcset attribute or are in a <picture> element, we
// always use the Imageset load type, even if we parsed no valid
// responsive sources from either, per spec.
type = eImageLoadType_Imageset;
}
triggeringPrincipal = mSrcTriggeringPrincipal;
}
}
if (!aAlwaysLoad && SelectedSourceMatchesLast(selectedSource)) {
// Update state when only density may have changed (i.e., the source to load
// hasn't changed, and we don't do any request at all). We need (apart from
// updating our internal state) to tell the image frame because its
// intrinsic size may have changed.
//
// In the case we actually trigger a new load, that load will trigger a call
// to nsImageFrame::NotifyNewCurrentRequest, which takes care of that for
// us.
SetDensity(currentDensity);
return NS_OK;
}
// Before we actually defer the lazy-loading
if (mLazyLoading) {
if (!selectedSource ||
!nsContentUtils::IsImageAvailable(this, selectedSource,
triggeringPrincipal, GetCORSMode())) {
return NS_OK;
}
StopLazyLoading(StartLoading::No);
}
nsresult rv = NS_ERROR_FAILURE;
// src triggers an error event on invalid URI, unlike other loads.
if (selectedSource || hasSrc) {
rv = LoadImage(selectedSource, aForce, aNotify, type, triggeringPrincipal);
}
mLastSelectedSource = selectedSource;
mCurrentDensity = currentDensity;
if (NS_FAILED(rv)) {
CancelImageRequests(aNotify);
}
return rv;
}
void HTMLImageElement::PictureSourceSrcsetChanged(nsIContent* aSourceNode,
const nsAString& aNewValue,
bool aNotify) {
MOZ_ASSERT(aSourceNode == this || IsPreviousSibling(aSourceNode, this),
"Should not be getting notifications for non-previous-siblings");
nsIContent* currentSrc =
mResponsiveSelector ? mResponsiveSelector->Content() : nullptr;
if (aSourceNode == currentSrc) {
// We're currently using this node as our responsive selector
// source.
nsCOMPtr<nsIPrincipal> principal;
if (aSourceNode == this) {
principal = mSrcsetTriggeringPrincipal;
} else if (auto* source = HTMLSourceElement::FromNode(aSourceNode)) {
principal = source->GetSrcsetTriggeringPrincipal();
}
mResponsiveSelector->SetCandidatesFromSourceSet(aNewValue, principal);
}
if (!mInDocResponsiveContent && IsInComposedDoc()) {
OwnerDoc()->AddResponsiveContent(this);
mInDocResponsiveContent = true;
}
// This always triggers the image update steps per the spec, even if
// we are not using this source.
UpdateSourceSyncAndQueueImageTask(true);
}
void HTMLImageElement::PictureSourceSizesChanged(nsIContent* aSourceNode,
const nsAString& aNewValue,
bool aNotify) {
MOZ_ASSERT(aSourceNode == this || IsPreviousSibling(aSourceNode, this),
"Should not be getting notifications for non-previous-siblings");
nsIContent* currentSrc =
mResponsiveSelector ? mResponsiveSelector->Content() : nullptr;
if (aSourceNode == currentSrc) {
// We're currently using this node as our responsive selector
// source.
mResponsiveSelector->SetSizesFromDescriptor(aNewValue);
}
// This always triggers the image update steps per the spec, even if
// we are not using this source.
UpdateSourceSyncAndQueueImageTask(true);
}
void HTMLImageElement::PictureSourceMediaOrTypeChanged(nsIContent* aSourceNode,
bool aNotify) {
MOZ_ASSERT(IsPreviousSibling(aSourceNode, this),
"Should not be getting notifications for non-previous-siblings");
// This always triggers the image update steps per the spec, even if
// we are not switching to/from this source
UpdateSourceSyncAndQueueImageTask(true);
}
void HTMLImageElement::PictureSourceDimensionChanged(
HTMLSourceElement* aSourceNode, bool aNotify) {
MOZ_ASSERT(IsPreviousSibling(aSourceNode, this),
"Should not be getting notifications for non-previous-siblings");
// "width" and "height" affect the dimension of images, but they don't have
// impact on the selection of <source> elements. In other words,
// UpdateResponsiveSource doesn't change the source, so all we need to do is
// just request restyle.
if (mResponsiveSelector && mResponsiveSelector->Content() == aSourceNode) {
InvalidateAttributeMapping();
}
}
void HTMLImageElement::PictureSourceAdded(HTMLSourceElement* aSourceNode) {
MOZ_ASSERT(!aSourceNode || IsPreviousSibling(aSourceNode, this),
"Should not be getting notifications for non-previous-siblings");
UpdateSourceSyncAndQueueImageTask(true);
}
void HTMLImageElement::PictureSourceRemoved(HTMLSourceElement* aSourceNode) {
MOZ_ASSERT(!aSourceNode || IsPreviousSibling(aSourceNode, this),
"Should not be getting notifications for non-previous-siblings");
UpdateSourceSyncAndQueueImageTask(true, aSourceNode);
}
bool HTMLImageElement::UpdateResponsiveSource(
const HTMLSourceElement* aSkippedSource) {
bool hadSelector = !!mResponsiveSelector;
nsIContent* currentSource =
mResponsiveSelector ? mResponsiveSelector->Content() : nullptr;
// Walk source nodes previous to ourselves if IsInPicture().
nsINode* candidateSource =
IsInPicture() ? GetParentElement()->GetFirstChild() : this;
// Initialize this as nullptr so we don't have to nullify it when runing out
// of siblings without finding ourself, e.g. XBL magic.
RefPtr<ResponsiveImageSelector> newResponsiveSelector = nullptr;
for (; candidateSource; candidateSource = candidateSource->GetNextSibling()) {
if (aSkippedSource == candidateSource) {
continue;
}
if (candidateSource == currentSource) {
// found no better source before current, re-run selection on
// that and keep it if it's still usable.
bool changed = mResponsiveSelector->SelectImage(true);
if (mResponsiveSelector->NumCandidates()) {
bool isUsableCandidate = true;
// an otherwise-usable source element may still have a media query that
// may not match any more.
if (candidateSource->IsHTMLElement(nsGkAtoms::source) &&
!SourceElementMatches(candidateSource->AsElement())) {
isUsableCandidate = false;
}
if (isUsableCandidate) {
// We are still using the current source, but the selected image may
// be changed, so always set the density from the selected image.
SetDensity(mResponsiveSelector->GetSelectedImageDensity());
return changed;
}
}
// no longer valid
newResponsiveSelector = nullptr;
if (candidateSource == this) {
// No further possibilities
break;
}
} else if (candidateSource == this) {
// We are the last possible source
newResponsiveSelector =
TryCreateResponsiveSelector(candidateSource->AsElement());
break;
} else if (auto* source = HTMLSourceElement::FromNode(candidateSource)) {
if (RefPtr<ResponsiveImageSelector> selector =
TryCreateResponsiveSelector(source)) {
newResponsiveSelector = selector.forget();
// This led to a valid source, stop
break;
}
}
}
// If we reach this point, either:
// - there was no selector originally, and there is not one now
// - there was no selector originally, and there is one now
// - there was a selector, and there is a different one now
// - there was a selector, and there is not one now
SetResponsiveSelector(std::move(newResponsiveSelector));
return hadSelector || mResponsiveSelector;
}
/*static */
bool HTMLImageElement::SupportedPictureSourceType(const nsAString& aType) {
nsAutoString type;
nsAutoString params;
nsContentUtils::SplitMimeType(aType, type, params);
if (type.IsEmpty()) {
return true;
}
return imgLoader::SupportImageWithMimeType(
NS_ConvertUTF16toUTF8(type), AcceptedMimeTypes::IMAGES_AND_DOCUMENTS);
}
bool HTMLImageElement::SourceElementMatches(Element* aSourceElement) {
MOZ_ASSERT(aSourceElement->IsHTMLElement(nsGkAtoms::source));
MOZ_ASSERT(IsInPicture());
MOZ_ASSERT(IsPreviousSibling(aSourceElement, this));
// Check media and type
auto* src = static_cast<HTMLSourceElement*>(aSourceElement);
if (!src->MatchesCurrentMedia()) {
return false;
}
nsAutoString type;
return !src->GetAttr(nsGkAtoms::type, type) ||
SupportedPictureSourceType(type);
}
already_AddRefed<ResponsiveImageSelector>
HTMLImageElement::TryCreateResponsiveSelector(Element* aSourceElement) {
nsCOMPtr<nsIPrincipal> principal;
// Skip if this is not a <source> with matching media query
bool isSourceTag = aSourceElement->IsHTMLElement(nsGkAtoms::source);
if (isSourceTag) {
if (!SourceElementMatches(aSourceElement)) {
return nullptr;
}
auto* source = HTMLSourceElement::FromNode(aSourceElement);
principal = source->GetSrcsetTriggeringPrincipal();
} else if (aSourceElement->IsHTMLElement(nsGkAtoms::img)) {
// Otherwise this is the <img> tag itself
MOZ_ASSERT(aSourceElement == this);
principal = mSrcsetTriggeringPrincipal;
}
// Skip if has no srcset or an empty srcset
nsString srcset;
if (!aSourceElement->GetAttr(nsGkAtoms::srcset, srcset)) {
return nullptr;
}
if (srcset.IsEmpty()) {
return nullptr;
}
// Try to parse
RefPtr<ResponsiveImageSelector> sel =
new ResponsiveImageSelector(aSourceElement);
if (!sel->SetCandidatesFromSourceSet(srcset, principal)) {
// No possible candidates, don't need to bother parsing sizes
return nullptr;
}
nsAutoString sizes;
aSourceElement->GetAttr(nsGkAtoms::sizes, sizes);
sel->SetSizesFromDescriptor(sizes);
// If this is the <img> tag, also pull in src as the default source
if (!isSourceTag) {
MOZ_ASSERT(aSourceElement == this);
if (mSrcURI) {
sel->SetDefaultSource(mSrcURI, mSrcTriggeringPrincipal);
}
}
return sel.forget();
}
/* static */
bool HTMLImageElement::SelectSourceForTagWithAttrs(
Document* aDocument, bool aIsSourceTag, const nsAString& aSrcAttr,
const nsAString& aSrcsetAttr, const nsAString& aSizesAttr,
const nsAString& aTypeAttr, const nsAString& aMediaAttr,
nsAString& aResult) {
MOZ_ASSERT(aIsSourceTag || (aTypeAttr.IsEmpty() && aMediaAttr.IsEmpty()),
"Passing type or media attrs makes no sense without aIsSourceTag");
MOZ_ASSERT(!aIsSourceTag || aSrcAttr.IsEmpty(),
"Passing aSrcAttr makes no sense with aIsSourceTag set");
if (aSrcsetAttr.IsEmpty()) {
if (!aIsSourceTag) {
// For an <img> with no srcset, we would always select the src attr.
aResult.Assign(aSrcAttr);
return true;
}
// Otherwise, a <source> without srcset is never selected
return false;
}
// Would not consider source tags with unsupported media or type
if (aIsSourceTag &&
((!aMediaAttr.IsVoid() && !HTMLSourceElement::WouldMatchMediaForDocument(
aMediaAttr, aDocument)) ||
(!aTypeAttr.IsVoid() && !SupportedPictureSourceType(aTypeAttr)))) {
return false;
}
// Using srcset or picture <source>, build a responsive selector for this tag.
RefPtr<ResponsiveImageSelector> sel = new ResponsiveImageSelector(aDocument);
sel->SetCandidatesFromSourceSet(aSrcsetAttr);
if (!aSizesAttr.IsEmpty()) {
sel->SetSizesFromDescriptor(aSizesAttr);
}
if (!aIsSourceTag) {
sel->SetDefaultSource(aSrcAttr);
}
if (sel->GetSelectedImageURLSpec(aResult)) {
return true;
}
if (!aIsSourceTag) {
// <img> tag with no match would definitively load nothing.
aResult.Truncate();
return true;
}
// <source> tags with no match would leave source yet-undetermined.
return false;
}
void HTMLImageElement::DestroyContent() {
// Clear mPendingImageLoadTask to avoid running LoadSelectedImage() after
// getting destroyed.
mPendingImageLoadTask = nullptr;
mResponsiveSelector = nullptr;
nsImageLoadingContent::Destroy();
nsGenericHTMLElement::DestroyContent();
}
void HTMLImageElement::MediaFeatureValuesChanged() {
UpdateSourceSyncAndQueueImageTask(false);
}
bool HTMLImageElement::ShouldLoadImage() const {
return OwnerDoc()->ShouldLoadImages();
}
void HTMLImageElement::SetLazyLoading() {
if (mLazyLoading) {
return;
}
// If scripting is disabled don't do lazy load.
//
// Same for printing.
Document* doc = OwnerDoc();
if (!doc->IsScriptEnabled() || doc->IsStaticDocument()) {
return;
}
doc->EnsureLazyLoadObserver().Observe(*this);
mLazyLoading = true;
UpdateImageState(true);
}
void HTMLImageElement::StartLoadingIfNeeded() {
if (!LoadingEnabled() || !ShouldLoadImage()) {
return;
}
// Use script runner for the case the adopt is from appendChild.
nsContentUtils::AddScriptRunner(
InResponsiveMode()
? NewRunnableMethod<bool>("dom::HTMLImageElement::QueueImageLoadTask",
this, &HTMLImageElement::QueueImageLoadTask,
true)
: NewRunnableMethod<bool>("dom::HTMLImageElement::MaybeLoadImage",
this, &HTMLImageElement::MaybeLoadImage,
true));
}
void HTMLImageElement::StopLazyLoading(StartLoading aStartLoading) {
if (!mLazyLoading) {
return;
}
mLazyLoading = false;
Document* doc = OwnerDoc();
if (auto* obs = doc->GetLazyLoadObserver()) {
obs->Unobserve(*this);
}
if (aStartLoading == StartLoading::Yes) {
StartLoadingIfNeeded();
}
}
const StyleLockedDeclarationBlock*
HTMLImageElement::GetMappedAttributesFromSource() const {
if (!IsInPicture() || !mResponsiveSelector) {
return nullptr;
}
const auto* source =
HTMLSourceElement::FromNodeOrNull(mResponsiveSelector->Content());
if (!source) {
return nullptr;
}
MOZ_ASSERT(IsPreviousSibling(source, this),
"Incorrect or out-of-date source");
return source->GetAttributesMappedForImage();
}
void HTMLImageElement::InvalidateAttributeMapping() {
if (!IsInPicture()) {
return;
}
nsPresContext* presContext = nsContentUtils::GetContextForContent(this);
if (!presContext) {
return;
}
// Note: Unfortunately, we have to use RESTYLE_SELF, instead of using
// RESTYLE_STYLE_ATTRIBUTE or other ways, to avoid re-selector-match because
// we are using Gecko_GetExtraContentStyleDeclarations() to retrieve the
// extra declaration block from |this|'s width and height attributes, and
// other restyle hints seems not enough.
// FIXME: We may refine this together with the restyle for presentation
// attributes in RestyleManger::AttributeChagned()
presContext->RestyleManager()->PostRestyleEvent(
this, RestyleHint::RESTYLE_SELF, nsChangeHint(0));
}
void HTMLImageElement::SetResponsiveSelector(
RefPtr<ResponsiveImageSelector>&& aSource) {
if (mResponsiveSelector == aSource) {
return;
}
mResponsiveSelector = std::move(aSource);
// Invalidate the style if needed.
InvalidateAttributeMapping();
// Update density.
SetDensity(mResponsiveSelector
? mResponsiveSelector->GetSelectedImageDensity()
: 1.0);
}
void HTMLImageElement::SetDensity(double aDensity) {
if (mCurrentDensity == aDensity) {
return;
}
mCurrentDensity = aDensity;
// Invalidate the reflow.
if (nsImageFrame* f = do_QueryFrame(GetPrimaryFrame())) {
f->ResponsiveContentDensityChanged();
}
}
void HTMLImageElement::QueueImageLoadTask(bool aAlwaysLoad) {
RefPtr<ImageLoadTask> task =
new ImageLoadTask(this, aAlwaysLoad, mUseUrgentStartForChannel);
// The task checks this to determine if it was the last
// queued event, and so earlier tasks are implicitly canceled.
mPendingImageLoadTask = task;
CycleCollectedJSContext::Get()->DispatchToMicroTask(task.forget());
}
FetchPriority HTMLImageElement::GetFetchPriorityForImage() const {
return nsGenericHTMLElement::GetFetchPriority();
}
} // namespace mozilla::dom