diff options
Diffstat (limited to 'dom/html/HTMLLinkElement.cpp')
| -rw-r--r-- | dom/html/HTMLLinkElement.cpp | 701 |
1 files changed, 701 insertions, 0 deletions
diff --git a/dom/html/HTMLLinkElement.cpp b/dom/html/HTMLLinkElement.cpp new file mode 100644 index 0000000000..e0c8e3aedd --- /dev/null +++ b/dom/html/HTMLLinkElement.cpp @@ -0,0 +1,701 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "mozilla/dom/HTMLLinkElement.h" + +#include "mozilla/AsyncEventDispatcher.h" +#include "mozilla/Attributes.h" +#include "mozilla/Components.h" +#include "mozilla/EventDispatcher.h" +#include "mozilla/MemoryReporting.h" +#include "mozilla/Preferences.h" +#include "mozilla/StaticPrefs_dom.h" +#include "mozilla/StaticPrefs_network.h" +#include "mozilla/dom/BindContext.h" +#include "mozilla/dom/DocumentInlines.h" +#include "mozilla/dom/HTMLLinkElementBinding.h" +#include "mozilla/dom/HTMLDNSPrefetch.h" +#include "mozilla/dom/ReferrerInfo.h" +#include "mozilla/dom/ScriptLoader.h" +#include "nsContentUtils.h" +#include "nsDOMTokenList.h" +#include "nsGenericHTMLElement.h" +#include "nsGkAtoms.h" +#include "nsIContentInlines.h" +#include "mozilla/dom/Document.h" +#include "nsINode.h" +#include "nsIPrefetchService.h" +#include "nsISizeOf.h" +#include "nsPIDOMWindow.h" +#include "nsReadableUtils.h" +#include "nsStyleConsts.h" +#include "nsUnicharUtils.h" +#include "nsWindowSizes.h" +#include "nsIContentPolicy.h" +#include "nsMimeTypes.h" +#include "imgLoader.h" +#include "MediaContainerType.h" +#include "DecoderDoctorDiagnostics.h" +#include "DecoderTraits.h" +#include "MediaList.h" +#include "nsAttrValueInlines.h" + +NS_IMPL_NS_NEW_HTML_ELEMENT(Link) + +namespace mozilla::dom { + +HTMLLinkElement::HTMLLinkElement( + already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo) + : nsGenericHTMLElement(std::move(aNodeInfo)) {} + +HTMLLinkElement::~HTMLLinkElement() { SupportsDNSPrefetch::Destroyed(*this); } + +NS_IMPL_CYCLE_COLLECTION_CLASS(HTMLLinkElement) + +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(HTMLLinkElement, + nsGenericHTMLElement) + tmp->LinkStyle::Traverse(cb); + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mRelList) + NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSizes) +NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END + +NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(HTMLLinkElement, + nsGenericHTMLElement) + tmp->LinkStyle::Unlink(); + NS_IMPL_CYCLE_COLLECTION_UNLINK(mRelList) + NS_IMPL_CYCLE_COLLECTION_UNLINK(mSizes) +NS_IMPL_CYCLE_COLLECTION_UNLINK_END + +NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED_0(HTMLLinkElement, + nsGenericHTMLElement) + +NS_IMPL_ELEMENT_CLONE(HTMLLinkElement) + +bool HTMLLinkElement::Disabled() const { + return GetBoolAttr(nsGkAtoms::disabled); +} + +void HTMLLinkElement::SetDisabled(bool aDisabled, ErrorResult& aRv) { + return SetHTMLBoolAttr(nsGkAtoms::disabled, aDisabled, aRv); +} + +nsresult HTMLLinkElement::BindToTree(BindContext& aContext, nsINode& aParent) { + nsresult rv = nsGenericHTMLElement::BindToTree(aContext, aParent); + NS_ENSURE_SUCCESS(rv, rv); + + if (IsInComposedDoc()) { + TryDNSPrefetchOrPreconnectOrPrefetchOrPreloadOrPrerender(); + } + + void (HTMLLinkElement::*update)() = + &HTMLLinkElement::UpdateStyleSheetInternal; + nsContentUtils::AddScriptRunner( + NewRunnableMethod("dom::HTMLLinkElement::BindToTree", this, update)); + + if (IsInUncomposedDoc() && + AttrValueIs(kNameSpaceID_None, nsGkAtoms::rel, nsGkAtoms::localization, + eIgnoreCase)) { + aContext.OwnerDoc().LocalizationLinkAdded(this); + } + + LinkAdded(); + + return rv; +} + +void HTMLLinkElement::LinkAdded() { + CreateAndDispatchEvent(OwnerDoc(), u"DOMLinkAdded"_ns); +} + +void HTMLLinkElement::LinkRemoved() { + CreateAndDispatchEvent(OwnerDoc(), u"DOMLinkRemoved"_ns); +} + +void HTMLLinkElement::UnbindFromTree(bool aNullParent) { + CancelDNSPrefetch(*this); + CancelPrefetchOrPreload(); + + // If this is reinserted back into the document it will not be + // from the parser. + Document* oldDoc = GetUncomposedDoc(); + ShadowRoot* oldShadowRoot = GetContainingShadow(); + + // We want to update the localization but only if the link is removed from a + // DOM change, and not because the document is going away. + bool ignore; + if (oldDoc && oldDoc->GetScriptHandlingObject(ignore) && + AttrValueIs(kNameSpaceID_None, nsGkAtoms::rel, nsGkAtoms::localization, + eIgnoreCase)) { + oldDoc->LocalizationLinkRemoved(this); + } + + CreateAndDispatchEvent(oldDoc, u"DOMLinkRemoved"_ns); + nsGenericHTMLElement::UnbindFromTree(aNullParent); + + Unused << UpdateStyleSheetInternal(oldDoc, oldShadowRoot); +} + +bool HTMLLinkElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute, + const nsAString& aValue, + nsIPrincipal* aMaybeScriptedPrincipal, + nsAttrValue& aResult) { + if (aNamespaceID == kNameSpaceID_None) { + if (aAttribute == nsGkAtoms::crossorigin) { + ParseCORSValue(aValue, aResult); + return true; + } + + if (aAttribute == nsGkAtoms::as) { + net::ParseAsValue(aValue, aResult); + return true; + } + + if (aAttribute == nsGkAtoms::sizes) { + aResult.ParseAtomArray(aValue); + return true; + } + + if (aAttribute == nsGkAtoms::integrity) { + aResult.ParseStringOrAtom(aValue); + return true; + } + } + + return nsGenericHTMLElement::ParseAttribute(aNamespaceID, aAttribute, aValue, + aMaybeScriptedPrincipal, aResult); +} + +void HTMLLinkElement::CreateAndDispatchEvent(Document* aDoc, + const nsAString& aEventName) { + if (!aDoc) return; + + // In the unlikely case that both rev is specified *and* rel=stylesheet, + // this code will cause the event to fire, on the principle that maybe the + // page really does want to specify that its author is a stylesheet. Since + // this should never actually happen and the performance hit is minimal, + // doing the "right" thing costs virtually nothing here, even if it doesn't + // make much sense. + static AttrArray::AttrValuesArray strings[] = { + nsGkAtoms::_empty, nsGkAtoms::stylesheet, nullptr}; + + if (!nsContentUtils::HasNonEmptyAttr(this, kNameSpaceID_None, + nsGkAtoms::rev) && + FindAttrValueIn(kNameSpaceID_None, nsGkAtoms::rel, strings, + eIgnoreCase) != AttrArray::ATTR_VALUE_NO_MATCH) { + return; + } + + RefPtr<AsyncEventDispatcher> asyncDispatcher = new AsyncEventDispatcher( + this, aEventName, CanBubble::eYes, ChromeOnlyDispatch::eYes); + // Always run async in order to avoid running script when the content + // sink isn't expecting it. + asyncDispatcher->PostDOMEvent(); +} + +void HTMLLinkElement::BeforeSetAttr(int32_t aNameSpaceID, nsAtom* aName, + const nsAttrValue* aValue, bool aNotify) { + if (aNameSpaceID == kNameSpaceID_None && + (aName == nsGkAtoms::href || aName == nsGkAtoms::rel)) { + CancelDNSPrefetch(*this); + CancelPrefetchOrPreload(); + } + + return nsGenericHTMLElement::BeforeSetAttr(aNameSpaceID, aName, aValue, + aNotify); +} + +void HTMLLinkElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName, + const nsAttrValue* aValue, + const nsAttrValue* aOldValue, + nsIPrincipal* aSubjectPrincipal, + bool aNotify) { + if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::href) { + mCachedURI = nullptr; + if (IsInUncomposedDoc()) { + CreateAndDispatchEvent(OwnerDoc(), u"DOMLinkChanged"_ns); + } + mTriggeringPrincipal = nsContentUtils::GetAttrTriggeringPrincipal( + this, aValue ? aValue->GetStringValue() : EmptyString(), + aSubjectPrincipal); + + // If the link has `rel=localization` and its `href` attribute is changed, + // update the list of localization links. + if (AttrValueIs(kNameSpaceID_None, nsGkAtoms::rel, nsGkAtoms::localization, + eIgnoreCase)) { + if (Document* doc = GetUncomposedDoc()) { + if (aOldValue) { + doc->LocalizationLinkRemoved(this); + } + if (aValue) { + doc->LocalizationLinkAdded(this); + } + } + } + } + + // If a link's `rel` attribute was changed from or to `localization`, + // update the list of localization links. + if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::rel) { + if (Document* doc = GetUncomposedDoc()) { + if ((aValue && aValue->Equals(nsGkAtoms::localization, eIgnoreCase)) && + (!aOldValue || + !aOldValue->Equals(nsGkAtoms::localization, eIgnoreCase))) { + doc->LocalizationLinkAdded(this); + } else if ((aOldValue && + aOldValue->Equals(nsGkAtoms::localization, eIgnoreCase)) && + (!aValue || + !aValue->Equals(nsGkAtoms::localization, eIgnoreCase))) { + doc->LocalizationLinkRemoved(this); + } + } + } + + if (aValue) { + if (aNameSpaceID == kNameSpaceID_None && + (aName == nsGkAtoms::href || aName == nsGkAtoms::rel || + aName == nsGkAtoms::title || aName == nsGkAtoms::media || + aName == nsGkAtoms::type || aName == nsGkAtoms::as || + aName == nsGkAtoms::crossorigin || aName == nsGkAtoms::disabled)) { + bool dropSheet = false; + if (aName == nsGkAtoms::rel) { + nsAutoString value; + aValue->ToString(value); + uint32_t linkTypes = ParseLinkTypes(value); + if (GetSheet()) { + dropSheet = !(linkTypes & eSTYLESHEET); + } + } + + if ((aName == nsGkAtoms::rel || aName == nsGkAtoms::href) && + IsInComposedDoc()) { + TryDNSPrefetchOrPreconnectOrPrefetchOrPreloadOrPrerender(); + } + + if ((aName == nsGkAtoms::as || aName == nsGkAtoms::type || + aName == nsGkAtoms::crossorigin || aName == nsGkAtoms::media) && + IsInComposedDoc()) { + UpdatePreload(aName, aValue, aOldValue); + } + + const bool forceUpdate = + dropSheet || aName == nsGkAtoms::title || aName == nsGkAtoms::media || + aName == nsGkAtoms::type || aName == nsGkAtoms::disabled; + + Unused << UpdateStyleSheetInternal( + nullptr, nullptr, forceUpdate ? ForceUpdate::Yes : ForceUpdate::No); + } + } else { + if (aNameSpaceID == kNameSpaceID_None) { + if (aName == nsGkAtoms::disabled) { + mExplicitlyEnabled = true; + } + // Since removing href or rel makes us no longer link to a stylesheet, + // force updates for those too. + if (aName == nsGkAtoms::href || aName == nsGkAtoms::rel || + aName == nsGkAtoms::title || aName == nsGkAtoms::media || + aName == nsGkAtoms::type || aName == nsGkAtoms::disabled) { + Unused << UpdateStyleSheetInternal(nullptr, nullptr, ForceUpdate::Yes); + } + if ((aName == nsGkAtoms::as || aName == nsGkAtoms::type || + aName == nsGkAtoms::crossorigin || aName == nsGkAtoms::media) && + IsInComposedDoc()) { + UpdatePreload(aName, aValue, aOldValue); + } + } + } + + return nsGenericHTMLElement::AfterSetAttr( + aNameSpaceID, aName, aValue, aOldValue, aSubjectPrincipal, aNotify); +} + +// Keep this and the arrays below in sync with ToLinkMask in LinkStyle.cpp. +#define SUPPORTED_REL_VALUES_BASE \ + "prefetch", "dns-prefetch", "stylesheet", "next", "alternate", "preconnect", \ + "icon", "search", nullptr + +static const DOMTokenListSupportedToken sSupportedRelValueCombinations[][12] = { + {SUPPORTED_REL_VALUES_BASE}, + {"manifest", SUPPORTED_REL_VALUES_BASE}, + {"preload", SUPPORTED_REL_VALUES_BASE}, + {"preload", "manifest", SUPPORTED_REL_VALUES_BASE}, + {"modulepreload", SUPPORTED_REL_VALUES_BASE}, + {"modulepreload", "manifest", SUPPORTED_REL_VALUES_BASE}, + {"modulepreload", "preload", SUPPORTED_REL_VALUES_BASE}, + {"modulepreload", "preload", "manifest", SUPPORTED_REL_VALUES_BASE}}; +#undef SUPPORTED_REL_VALUES_BASE + +nsDOMTokenList* HTMLLinkElement::RelList() { + if (!mRelList) { + int index = (StaticPrefs::dom_manifest_enabled() ? 1 : 0) | + (StaticPrefs::network_preload() ? 2 : 0) | + (StaticPrefs::network_modulepreload() ? 4 : 0); + + mRelList = new nsDOMTokenList(this, nsGkAtoms::rel, + sSupportedRelValueCombinations[index]); + } + return mRelList; +} + +Maybe<LinkStyle::SheetInfo> HTMLLinkElement::GetStyleSheetInfo() { + nsAutoString rel; + GetAttr(kNameSpaceID_None, nsGkAtoms::rel, rel); + uint32_t linkTypes = ParseLinkTypes(rel); + if (!(linkTypes & eSTYLESHEET)) { + return Nothing(); + } + + if (!IsCSSMimeTypeAttributeForLinkElement(*this)) { + return Nothing(); + } + + if (Disabled()) { + return Nothing(); + } + + nsAutoString title; + nsAutoString media; + GetTitleAndMediaForElement(*this, title, media); + + bool alternate = linkTypes & eALTERNATE; + if (alternate && title.IsEmpty()) { + // alternates must have title. + return Nothing(); + } + + if (!HasNonEmptyAttr(nsGkAtoms::href)) { + return Nothing(); + } + + nsAutoString integrity; + GetAttr(nsGkAtoms::integrity, integrity); + + nsCOMPtr<nsIURI> uri = GetURI(); + nsCOMPtr<nsIPrincipal> prin = mTriggeringPrincipal; + + nsAutoString nonce; + nsString* cspNonce = static_cast<nsString*>(GetProperty(nsGkAtoms::nonce)); + if (cspNonce) { + nonce = *cspNonce; + } + + return Some(SheetInfo{ + *OwnerDoc(), + this, + uri.forget(), + prin.forget(), + MakeAndAddRef<ReferrerInfo>(*this), + GetCORSMode(), + title, + media, + integrity, + nonce, + alternate ? HasAlternateRel::Yes : HasAlternateRel::No, + IsInline::No, + mExplicitlyEnabled ? IsExplicitlyEnabled::Yes : IsExplicitlyEnabled::No, + }); +} + +void HTMLLinkElement::AddSizeOfExcludingThis(nsWindowSizes& aSizes, + size_t* aNodeSize) const { + nsGenericHTMLElement::AddSizeOfExcludingThis(aSizes, aNodeSize); + if (nsCOMPtr<nsISizeOf> iface = do_QueryInterface(mCachedURI)) { + *aNodeSize += iface->SizeOfExcludingThis(aSizes.mState.mMallocSizeOf); + } +} + +JSObject* HTMLLinkElement::WrapNode(JSContext* aCx, + JS::Handle<JSObject*> aGivenProto) { + return HTMLLinkElement_Binding::Wrap(aCx, this, aGivenProto); +} + +void HTMLLinkElement::GetAs(nsAString& aResult) { + GetEnumAttr(nsGkAtoms::as, "", aResult); +} + +void HTMLLinkElement::GetContentPolicyMimeTypeMedia( + nsAttrValue& aAsAttr, nsContentPolicyType& aPolicyType, nsString& aMimeType, + nsAString& aMedia) { + nsAutoString as; + GetAttr(kNameSpaceID_None, nsGkAtoms::as, as); + net::ParseAsValue(as, aAsAttr); + aPolicyType = net::AsValueToContentPolicy(aAsAttr); + + nsAutoString type; + GetAttr(kNameSpaceID_None, nsGkAtoms::type, type); + nsAutoString notUsed; + nsContentUtils::SplitMimeType(type, aMimeType, notUsed); + + GetAttr(kNameSpaceID_None, nsGkAtoms::media, aMedia); +} + +void HTMLLinkElement:: + TryDNSPrefetchOrPreconnectOrPrefetchOrPreloadOrPrerender() { + MOZ_ASSERT(IsInComposedDoc()); + if (!HasAttr(nsGkAtoms::href)) { + return; + } + + nsAutoString rel; + if (!GetAttr(nsGkAtoms::rel, rel)) { + return; + } + + if (!nsContentUtils::PrefetchPreloadEnabled(OwnerDoc()->GetDocShell())) { + return; + } + + uint32_t linkTypes = ParseLinkTypes(rel); + + if ((linkTypes & ePREFETCH) || (linkTypes & eNEXT)) { + nsCOMPtr<nsIPrefetchService> prefetchService( + components::Prefetch::Service()); + if (prefetchService) { + if (nsCOMPtr<nsIURI> uri = GetURI()) { + auto referrerInfo = MakeRefPtr<ReferrerInfo>(*this); + prefetchService->PrefetchURI(uri, referrerInfo, this, + linkTypes & ePREFETCH); + return; + } + } + } + + if (linkTypes & ePRELOAD) { + if (nsCOMPtr<nsIURI> uri = GetURI()) { + nsContentPolicyType policyType; + + nsAttrValue asAttr; + nsAutoString mimeType; + nsAutoString media; + GetContentPolicyMimeTypeMedia(asAttr, policyType, mimeType, media); + + if (policyType == nsIContentPolicy::TYPE_INVALID || + !net::CheckPreloadAttrs(asAttr, mimeType, media, OwnerDoc())) { + // Ignore preload with a wrong or empty as attribute. + net::WarnIgnoredPreload(*OwnerDoc(), *uri); + return; + } + + StartPreload(policyType); + return; + } + } + + if (linkTypes & eMODULE_PRELOAD) { + ScriptLoader* scriptLoader = OwnerDoc()->ScriptLoader(); + ModuleLoader* moduleLoader = scriptLoader->GetModuleLoader(); + + if (!moduleLoader) { + // For the print preview documents, at this moment it doesn't have module + // loader yet, as the (print preview) document is not attached to the + // nsIContentViewer yet, so it doesn't have the GlobalObject. + // Also, the script elements won't be processed as they are also cloned + // from the original document. + // So we simply bail out if the module loader is null. + return; + } + + if (!StaticPrefs::network_modulepreload()) { + // Keep behavior from https://phabricator.services.mozilla.com/D149371, + // prior to main implementation of modulepreload + moduleLoader->DisallowImportMaps(); + return; + } + + // https://html.spec.whatwg.org/multipage/semantics.html#processing-the-media-attribute + // TODO: apply this check for all linkTypes + nsAutoString media; + if (GetAttr(nsGkAtoms::media, media)) { + RefPtr<mozilla::dom::MediaList> mediaList = + mozilla::dom::MediaList::Create(NS_ConvertUTF16toUTF8(media)); + if (!mediaList->Matches(*OwnerDoc())) { + return; + } + } + + // TODO: per spec, apply this check for ePREFETCH as well + if (!HasNonEmptyAttr(nsGkAtoms::href)) { + return; + } + + nsAutoString as; + GetAttr(nsGkAtoms::as, as); + + if (!net::IsScriptLikeOrInvalid(as)) { + RefPtr<AsyncEventDispatcher> asyncDispatcher = new AsyncEventDispatcher( + this, u"error"_ns, CanBubble::eNo, ChromeOnlyDispatch::eNo); + asyncDispatcher->PostDOMEvent(); + return; + } + + nsCOMPtr<nsIURI> uri = GetURI(); + if (!uri) { + return; + } + + // https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-modulepreload-module-script-graph + // Step 1. Disallow further import maps given settings object. + moduleLoader->DisallowImportMaps(); + + StartPreload(nsIContentPolicy::TYPE_SCRIPT); + return; + } + + if (linkTypes & ePRECONNECT) { + if (nsCOMPtr<nsIURI> uri = GetURI()) { + OwnerDoc()->MaybePreconnect( + uri, AttrValueToCORSMode(GetParsedAttr(nsGkAtoms::crossorigin))); + return; + } + } + + if (linkTypes & eDNS_PREFETCH) { + TryDNSPrefetch(*this); + } +} + +void HTMLLinkElement::UpdatePreload(nsAtom* aName, const nsAttrValue* aValue, + const nsAttrValue* aOldValue) { + MOZ_ASSERT(IsInComposedDoc()); + + if (!HasAttr(nsGkAtoms::href)) { + return; + } + + nsAutoString rel; + if (!GetAttr(nsGkAtoms::rel, rel)) { + return; + } + + if (!nsContentUtils::PrefetchPreloadEnabled(OwnerDoc()->GetDocShell())) { + return; + } + + uint32_t linkTypes = ParseLinkTypes(rel); + + if (!(linkTypes & ePRELOAD)) { + return; + } + + nsCOMPtr<nsIURI> uri = GetURI(); + if (!uri) { + return; + } + + nsAttrValue asAttr; + nsContentPolicyType asPolicyType; + nsAutoString mimeType; + nsAutoString media; + GetContentPolicyMimeTypeMedia(asAttr, asPolicyType, mimeType, media); + + if (asPolicyType == nsIContentPolicy::TYPE_INVALID || + !net::CheckPreloadAttrs(asAttr, mimeType, media, OwnerDoc())) { + // Ignore preload with a wrong or empty as attribute, but be sure to cancel + // the old one. + CancelPrefetchOrPreload(); + net::WarnIgnoredPreload(*OwnerDoc(), *uri); + return; + } + + if (aName == nsGkAtoms::crossorigin) { + CORSMode corsMode = AttrValueToCORSMode(aValue); + CORSMode oldCorsMode = AttrValueToCORSMode(aOldValue); + if (corsMode != oldCorsMode) { + CancelPrefetchOrPreload(); + StartPreload(asPolicyType); + } + return; + } + + nsContentPolicyType oldPolicyType; + + if (aName == nsGkAtoms::as) { + if (aOldValue) { + oldPolicyType = net::AsValueToContentPolicy(*aOldValue); + if (!net::CheckPreloadAttrs(*aOldValue, mimeType, media, OwnerDoc())) { + oldPolicyType = nsIContentPolicy::TYPE_INVALID; + } + } else { + oldPolicyType = nsIContentPolicy::TYPE_INVALID; + } + } else if (aName == nsGkAtoms::type) { + nsAutoString oldType; + nsAutoString notUsed; + if (aOldValue) { + aOldValue->ToString(oldType); + } + nsAutoString oldMimeType; + nsContentUtils::SplitMimeType(oldType, oldMimeType, notUsed); + if (net::CheckPreloadAttrs(asAttr, oldMimeType, media, OwnerDoc())) { + oldPolicyType = asPolicyType; + } else { + oldPolicyType = nsIContentPolicy::TYPE_INVALID; + } + } else { + MOZ_ASSERT(aName == nsGkAtoms::media); + nsAutoString oldMedia; + if (aOldValue) { + aOldValue->ToString(oldMedia); + } + if (net::CheckPreloadAttrs(asAttr, mimeType, oldMedia, OwnerDoc())) { + oldPolicyType = asPolicyType; + } else { + oldPolicyType = nsIContentPolicy::TYPE_INVALID; + } + } + + if (asPolicyType != oldPolicyType && + oldPolicyType != nsIContentPolicy::TYPE_INVALID) { + CancelPrefetchOrPreload(); + } + + // Trigger a new preload if the policy type has changed. + if (asPolicyType != oldPolicyType) { + StartPreload(asPolicyType); + } +} + +void HTMLLinkElement::CancelPrefetchOrPreload() { + CancelPreload(); + + nsCOMPtr<nsIPrefetchService> prefetchService(components::Prefetch::Service()); + if (prefetchService) { + if (nsCOMPtr<nsIURI> uri = GetURI()) { + prefetchService->CancelPrefetchPreloadURI(uri, this); + } + } +} + +void HTMLLinkElement::StartPreload(nsContentPolicyType aPolicyType) { + MOZ_ASSERT(!mPreload, "Forgot to cancel the running preload"); + RefPtr<PreloaderBase> preload = + OwnerDoc()->Preloads().PreloadLinkElement(this, aPolicyType); + mPreload = preload.get(); +} + +void HTMLLinkElement::CancelPreload() { + if (mPreload) { + // This will cancel the loading channel if this was the last referred node + // and the preload is not used up until now to satisfy a regular tag load + // request. + mPreload->RemoveLinkPreloadNode(this); + mPreload = nullptr; + } +} + +bool HTMLLinkElement::IsCSSMimeTypeAttributeForLinkElement( + const Element& aSelf) { + // Processing the type attribute per + // https://html.spec.whatwg.org/multipage/semantics.html#processing-the-type-attribute + // for HTML link elements. + nsAutoString type; + nsAutoString mimeType; + nsAutoString notUsed; + aSelf.GetAttr(kNameSpaceID_None, nsGkAtoms::type, type); + nsContentUtils::SplitMimeType(type, mimeType, notUsed); + return mimeType.IsEmpty() || mimeType.LowerCaseEqualsLiteral("text/css"); +} + +} // namespace mozilla::dom |