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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
* 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/EventStates.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Preferences.h"
#include "mozilla/StaticPrefs_network.h"
#include "mozilla/dom/BindContext.h"
#include "mozilla/dom/DocumentInlines.h"
#include "mozilla/dom/HTMLLinkElementBinding.h"
#include "nsContentUtils.h"
#include "nsDOMTokenList.h"
#include "nsGenericHTMLElement.h"
#include "nsGkAtoms.h"
#include "nsHTMLDNSPrefetch.h"
#include "nsIContentInlines.h"
#include "mozilla/dom/Document.h"
#include "nsINode.h"
#include "nsIPrefetchService.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"
#define LINK_ELEMENT_FLAG_BIT(n_) \
NODE_FLAG_BIT(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + (n_))
// Link element specific bits
enum {
// Indicates that a DNS Prefetch has been requested from this Link element.
HTML_LINK_DNS_PREFETCH_REQUESTED = LINK_ELEMENT_FLAG_BIT(0),
// Indicates that a DNS Prefetch was added to the deferral queue
HTML_LINK_DNS_PREFETCH_DEFERRED = LINK_ELEMENT_FLAG_BIT(1)
};
#undef LINK_ELEMENT_FLAG_BIT
ASSERT_NODE_FLAGS_SPACE(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET + 2);
NS_IMPL_NS_NEW_HTML_ELEMENT(Link)
namespace mozilla {
namespace dom {
HTMLLinkElement::HTMLLinkElement(
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
: nsGenericHTMLElement(std::move(aNodeInfo)), Link(this) {}
HTMLLinkElement::~HTMLLinkElement() = default;
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(HTMLLinkElement,
nsGenericHTMLElement, Link)
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);
}
void HTMLLinkElement::OnDNSPrefetchRequested() {
UnsetFlags(HTML_LINK_DNS_PREFETCH_DEFERRED);
SetFlags(HTML_LINK_DNS_PREFETCH_REQUESTED);
}
void HTMLLinkElement::OnDNSPrefetchDeferred() {
UnsetFlags(HTML_LINK_DNS_PREFETCH_REQUESTED);
SetFlags(HTML_LINK_DNS_PREFETCH_DEFERRED);
}
bool HTMLLinkElement::HasDeferredDNSPrefetchRequest() {
return HasFlag(HTML_LINK_DNS_PREFETCH_DEFERRED);
}
nsresult HTMLLinkElement::BindToTree(BindContext& aContext, nsINode& aParent) {
Link::ResetLinkState(false, Link::ElementHasHref());
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) {
// Cancel any DNS prefetches
// Note: Must come before ResetLinkState. If called after, it will recreate
// mCachedURI based on data that is invalid - due to a call to GetHostname.
CancelDNSPrefetch(HTML_LINK_DNS_PREFETCH_DEFERRED,
HTML_LINK_DNS_PREFETCH_REQUESTED);
CancelPrefetchOrPreload();
// Without removing the link state we risk a dangling pointer
// in the mStyledLinks hashtable
Link::ResetLinkState(false, Link::ElementHasHref());
// 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) {
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 Element::AttrValuesArray strings[] = {nsGkAtoms::_empty,
nsGkAtoms::stylesheet, nullptr};
if (!nsContentUtils::HasNonEmptyAttr(this, kNameSpaceID_None,
nsGkAtoms::rev) &&
FindAttrValueIn(kNameSpaceID_None, nsGkAtoms::rel, strings,
eIgnoreCase) != 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();
}
nsresult HTMLLinkElement::BeforeSetAttr(int32_t aNameSpaceID, nsAtom* aName,
const nsAttrValueOrString* aValue,
bool aNotify) {
if (aNameSpaceID == kNameSpaceID_None &&
(aName == nsGkAtoms::href || aName == nsGkAtoms::rel)) {
CancelDNSPrefetch(HTML_LINK_DNS_PREFETCH_DEFERRED,
HTML_LINK_DNS_PREFETCH_REQUESTED);
CancelPrefetchOrPreload();
}
return nsGenericHTMLElement::BeforeSetAttr(aNameSpaceID, aName, aValue,
aNotify);
}
nsresult HTMLLinkElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
const nsAttrValue* aValue,
const nsAttrValue* aOldValue,
nsIPrincipal* aSubjectPrincipal,
bool aNotify) {
// It's safe to call ResetLinkState here because our new attr value has
// already been set or unset. ResetLinkState needs the updated attribute
// value because notifying the document that content states have changed will
// call IntrinsicState, which will try to get updated information about the
// visitedness from Link.
if (aName == nsGkAtoms::href && kNameSpaceID_None == aNameSpaceID) {
bool hasHref = aValue;
Link::ResetLinkState(!!aNotify, hasHref);
if (IsInUncomposedDoc()) {
CreateAndDispatchEvent(OwnerDoc(), u"DOMLinkChanged"_ns);
}
}
if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::href) {
mTriggeringPrincipal = nsContentUtils::GetAttrTriggeringPrincipal(
this, aValue ? aValue->GetStringValue() : EmptyString(),
aSubjectPrincipal);
}
// 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 the link has `rel=localization` and its `href` attribute is changed,
// update the list of localization links.
if (aNameSpaceID == kNameSpaceID_None && aName == nsGkAtoms::href &&
AttrValueIs(kNameSpaceID_None, nsGkAtoms::rel, nsGkAtoms::localization,
eIgnoreCase)) {
if (Document* doc = GetUncomposedDoc()) {
if (aOldValue) {
doc->LocalizationLinkRemoved(this);
}
if (aValue) {
doc->LocalizationLinkAdded(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);
}
void HTMLLinkElement::GetEventTargetParent(EventChainPreVisitor& aVisitor) {
GetEventTargetParentForAnchors(aVisitor);
}
nsresult HTMLLinkElement::PostHandleEvent(EventChainPostVisitor& aVisitor) {
return PostHandleEventForAnchors(aVisitor);
}
bool HTMLLinkElement::IsLink(nsIURI** aURI) const { return IsHTMLLink(aURI); }
void HTMLLinkElement::GetLinkTarget(nsAString& aTarget) {
GetAttr(kNameSpaceID_None, nsGkAtoms::target, aTarget);
if (aTarget.IsEmpty()) {
GetBaseTarget(aTarget);
}
}
static const DOMTokenListSupportedToken sSupportedRelValues[] = {
// Keep this and the one below in sync with ToLinkMask in
// LinkStyle.cpp.
// "preload" must come first because it can be disabled.
"preload", "prefetch", "dns-prefetch", "stylesheet", "next",
"alternate", "preconnect", "icon", "search", nullptr};
static const DOMTokenListSupportedToken sSupportedRelValuesWithManifest[] = {
// Keep this in sync with ToLinkMask in LinkStyle.cpp.
// "preload" and "manifest" must come first because they can be disabled.
"preload", "manifest", "prefetch", "dns-prefetch", "stylesheet", "next",
"alternate", "preconnect", "icon", "search", nullptr};
nsDOMTokenList* HTMLLinkElement::RelList() {
if (!mRelList) {
auto preload = StaticPrefs::network_preload();
auto manifest = StaticPrefs::dom_manifest_enabled();
if (manifest && preload) {
mRelList = new nsDOMTokenList(this, nsGkAtoms::rel,
sSupportedRelValuesWithManifest);
} else if (manifest && !preload) {
mRelList = new nsDOMTokenList(this, nsGkAtoms::rel,
&sSupportedRelValuesWithManifest[1]);
} else if (!manifest && preload) {
mRelList = new nsDOMTokenList(this, nsGkAtoms::rel, sSupportedRelValues);
} else { // both false...drop preload
mRelList =
new nsDOMTokenList(this, nsGkAtoms::rel, &sSupportedRelValues[1]);
}
}
return mRelList;
}
already_AddRefed<nsIURI> HTMLLinkElement::GetHrefURI() const {
return GetHrefURIForAnchors();
}
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();
}
nsAutoString href;
GetAttr(kNameSpaceID_None, nsGkAtoms::href, href);
if (href.IsEmpty()) {
return Nothing();
}
nsAutoString integrity;
GetAttr(kNameSpaceID_None, nsGkAtoms::integrity, integrity);
nsCOMPtr<nsIURI> uri = Link::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,
});
}
EventStates HTMLLinkElement::IntrinsicState() const {
return Link::LinkState() | nsGenericHTMLElement::IntrinsicState();
}
void HTMLLinkElement::AddSizeOfExcludingThis(nsWindowSizes& aSizes,
size_t* aNodeSize) const {
nsGenericHTMLElement::AddSizeOfExcludingThis(aSizes, aNodeSize);
*aNodeSize += Link::SizeOfExcludingThis(aSizes.mState);
}
JSObject* HTMLLinkElement::WrapNode(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return HTMLLinkElement_Binding::Wrap(aCx, this, aGivenProto);
}
void HTMLLinkElement::GetAs(nsAString& aResult) {
GetEnumAttr(nsGkAtoms::as, EmptyCString().get(), aResult);
}
static const nsAttrValue::EnumTable kAsAttributeTable[] = {
{"", DESTINATION_INVALID}, {"audio", DESTINATION_AUDIO},
{"font", DESTINATION_FONT}, {"image", DESTINATION_IMAGE},
{"script", DESTINATION_SCRIPT}, {"style", DESTINATION_STYLE},
{"track", DESTINATION_TRACK}, {"video", DESTINATION_VIDEO},
{"fetch", DESTINATION_FETCH}, {nullptr, 0}};
/* static */
void HTMLLinkElement::ParseAsValue(const nsAString& aValue,
nsAttrValue& aResult) {
DebugOnly<bool> success =
aResult.ParseEnumValue(aValue, kAsAttributeTable, false,
// default value is a empty string
// if aValue is not a value we
// understand
&kAsAttributeTable[0]);
MOZ_ASSERT(success);
}
/* static */
nsContentPolicyType HTMLLinkElement::AsValueToContentPolicy(
const nsAttrValue& aValue) {
switch (aValue.GetEnumValue()) {
case DESTINATION_INVALID:
return nsIContentPolicy::TYPE_INVALID;
case DESTINATION_AUDIO:
return nsIContentPolicy::TYPE_INTERNAL_AUDIO;
case DESTINATION_TRACK:
return nsIContentPolicy::TYPE_INTERNAL_TRACK;
case DESTINATION_VIDEO:
return nsIContentPolicy::TYPE_INTERNAL_VIDEO;
case DESTINATION_FONT:
return nsIContentPolicy::TYPE_FONT;
case DESTINATION_IMAGE:
return nsIContentPolicy::TYPE_IMAGE;
case DESTINATION_SCRIPT:
return nsIContentPolicy::TYPE_SCRIPT;
case DESTINATION_STYLE:
return nsIContentPolicy::TYPE_STYLESHEET;
case DESTINATION_FETCH:
return nsIContentPolicy::TYPE_INTERNAL_FETCH_PRELOAD;
}
return nsIContentPolicy::TYPE_INVALID;
}
void HTMLLinkElement::GetContentPolicyMimeTypeMedia(
nsAttrValue& aAsAttr, nsContentPolicyType& aPolicyType, nsString& aMimeType,
nsAString& aMedia) {
nsAutoString as;
GetAttr(kNameSpaceID_None, nsGkAtoms::as, as);
ParseAsValue(as, aAsAttr);
aPolicyType = 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 (!ElementHasHref()) {
return;
}
nsAutoString rel;
if (!GetAttr(kNameSpaceID_None, 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) {
nsCOMPtr<nsIURI> uri(GetURI());
if (uri) {
auto referrerInfo = MakeRefPtr<ReferrerInfo>(*this);
prefetchService->PrefetchURI(uri, referrerInfo, this,
linkTypes & ePREFETCH);
return;
}
}
}
if (linkTypes & ePRELOAD) {
nsCOMPtr<nsIURI> uri(GetURI());
if (uri) {
nsContentPolicyType policyType;
nsAttrValue asAttr;
nsAutoString mimeType;
nsAutoString media;
GetContentPolicyMimeTypeMedia(asAttr, policyType, mimeType, media);
if (policyType == nsIContentPolicy::TYPE_INVALID) {
// Ignore preload with a wrong or empty as attribute.
return;
}
if (!CheckPreloadAttrs(asAttr, mimeType, media, OwnerDoc())) {
policyType = nsIContentPolicy::TYPE_INVALID;
}
StartPreload(policyType);
return;
}
}
if (linkTypes & ePRECONNECT) {
if (nsCOMPtr<nsIURI> uri = GetURI()) {
OwnerDoc()->MaybePreconnect(
uri, AttrValueToCORSMode(GetParsedAttr(nsGkAtoms::crossorigin)));
return;
}
}
if (linkTypes & eDNS_PREFETCH) {
if (nsHTMLDNSPrefetch::IsAllowed(OwnerDoc())) {
nsHTMLDNSPrefetch::PrefetchLow(this);
}
}
}
void HTMLLinkElement::UpdatePreload(nsAtom* aName, const nsAttrValue* aValue,
const nsAttrValue* aOldValue) {
MOZ_ASSERT(IsInComposedDoc());
if (!ElementHasHref()) {
return;
}
nsAutoString rel;
if (!GetAttr(kNameSpaceID_None, 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) {
// Ignore preload with a wrong or empty as attribute, but be sure to cancel
// the old one.
CancelPrefetchOrPreload();
return;
}
nsContentPolicyType policyType = asPolicyType;
if (!CheckPreloadAttrs(asAttr, mimeType, media, OwnerDoc())) {
policyType = nsIContentPolicy::TYPE_INVALID;
}
if (aName == nsGkAtoms::crossorigin) {
CORSMode corsMode = AttrValueToCORSMode(aValue);
CORSMode oldCorsMode = AttrValueToCORSMode(aOldValue);
if (corsMode != oldCorsMode) {
CancelPrefetchOrPreload();
StartPreload(policyType);
}
return;
}
nsContentPolicyType oldPolicyType;
if (aName == nsGkAtoms::as) {
if (aOldValue) {
oldPolicyType = AsValueToContentPolicy(*aOldValue);
if (!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);
} else {
oldType = EmptyString();
}
nsAutoString oldMimeType;
nsContentUtils::SplitMimeType(oldType, oldMimeType, notUsed);
if (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);
} else {
oldMedia = EmptyString();
}
if (CheckPreloadAttrs(asAttr, mimeType, oldMedia, OwnerDoc())) {
oldPolicyType = asPolicyType;
} else {
oldPolicyType = nsIContentPolicy::TYPE_INVALID;
}
}
if ((policyType != oldPolicyType) &&
(oldPolicyType != nsIContentPolicy::TYPE_INVALID)) {
CancelPrefetchOrPreload();
}
// Trigger a new preload if the policy type has changed.
// Also trigger load if the new policy type is invalid, this will only
// trigger an error event.
if ((policyType != oldPolicyType) ||
(policyType == nsIContentPolicy::TYPE_INVALID)) {
StartPreload(policyType);
}
}
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 policyType) {
MOZ_ASSERT(!mPreload, "Forgot to cancel the running preload");
auto referrerInfo = MakeRefPtr<ReferrerInfo>(*this);
RefPtr<PreloaderBase> preload =
OwnerDoc()->Preloads().PreloadLinkElement(this, policyType, referrerInfo);
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;
}
}
// We will use official mime-types from:
// We do not support old deprecated mime-types for preload feature.
// (We currectly do not support font/collection)
static uint32_t StyleLinkElementFontMimeTypesNum = 5;
static const char* StyleLinkElementFontMimeTypes[] = {
"font/otf", "font/sfnt", "font/ttf", "font/woff", "font/woff2"};
bool IsFontMimeType(const nsAString& aType) {
if (aType.IsEmpty()) {
return true;
}
for (uint32_t i = 0; i < StyleLinkElementFontMimeTypesNum; i++) {
if (aType.EqualsASCII(StyleLinkElementFontMimeTypes[i])) {
return true;
}
}
return false;
}
bool HTMLLinkElement::CheckPreloadAttrs(const nsAttrValue& aAs,
const nsAString& aType,
const nsAString& aMedia,
Document* aDocument) {
nsContentPolicyType policyType = AsValueToContentPolicy(aAs);
if (policyType == nsIContentPolicy::TYPE_INVALID) {
return false;
}
// Check if media attribute is valid.
if (!aMedia.IsEmpty()) {
RefPtr<MediaList> mediaList = MediaList::Create(aMedia);
if (!mediaList->Matches(*aDocument)) {
return false;
}
}
if (aType.IsEmpty()) {
return true;
}
nsString type = nsString(aType);
ToLowerCase(type);
if (policyType == nsIContentPolicy::TYPE_INTERNAL_FETCH_PRELOAD) {
return true;
}
if (policyType == nsIContentPolicy::TYPE_MEDIA) {
if (aAs.GetEnumValue() == DESTINATION_TRACK) {
return type.EqualsASCII("text/vtt");
}
Maybe<MediaContainerType> mimeType = MakeMediaContainerType(aType);
if (!mimeType) {
return false;
}
DecoderDoctorDiagnostics diagnostics;
CanPlayStatus status =
DecoderTraits::CanHandleContainerType(*mimeType, &diagnostics);
// Preload if this return CANPLAY_YES and CANPLAY_MAYBE.
return status != CANPLAY_NO;
}
if (policyType == nsIContentPolicy::TYPE_FONT) {
return IsFontMimeType(type);
}
if (policyType == nsIContentPolicy::TYPE_IMAGE) {
return imgLoader::SupportImageWithMimeType(
NS_ConvertUTF16toUTF8(type).get(),
AcceptedMimeTypes::IMAGES_AND_DOCUMENTS);
}
if (policyType == nsIContentPolicy::TYPE_SCRIPT) {
return nsContentUtils::IsJavascriptMIMEType(type);
}
if (policyType == nsIContentPolicy::TYPE_STYLESHEET) {
return type.EqualsASCII("text/css");
}
return false;
}
bool HTMLLinkElement::IsCSSMimeTypeAttributeForLinkElement(
const Element& aSelf) {
// Processing the type attribute per
// 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 dom
} // namespace mozilla