gecko-dev/layout/style/StyleSheet.cpp
Emilio Cobos Álvarez 60812fc63c Bug 1711437 - Don't EnsureUniqueInner from the cssRules getter. r=layout-reviewers,jfkthame
Instead, fix up the various content data structures when the stylesheet
is mutated. This makes reading a stylesheet not disable style sharing.

Differential Revision: https://phabricator.services.mozilla.com/D115203
2021-07-20 13:17:02 +00:00

1497 lines
47 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/StyleSheet.h"
#include "mozilla/Assertions.h"
#include "mozilla/BasePrincipal.h"
#include "mozilla/ComputedStyleInlines.h"
#include "mozilla/css/ErrorReporter.h"
#include "mozilla/css/GroupRule.h"
#include "mozilla/dom/CSSImportRule.h"
#include "mozilla/dom/CSSRuleList.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/MediaList.h"
#include "mozilla/dom/Promise.h"
#include "mozilla/dom/ShadowRoot.h"
#include "mozilla/dom/ShadowRootBinding.h"
#include "mozilla/NullPrincipal.h"
#include "mozilla/ServoBindings.h"
#include "mozilla/ServoCSSRuleList.h"
#include "mozilla/ServoStyleSet.h"
#include "mozilla/StaticPrefs_layout.h"
#include "mozilla/StyleSheetInlines.h"
#include "mozilla/css/SheetLoadData.h"
#include "mozAutoDocUpdate.h"
#include "SheetLoadData.h"
namespace mozilla {
using namespace dom;
StyleSheet::StyleSheet(css::SheetParsingMode aParsingMode, CORSMode aCORSMode,
const dom::SRIMetadata& aIntegrity)
: mParentSheet(nullptr),
mRelevantGlobal(nullptr),
mConstructorDocument(nullptr),
mDocumentOrShadowRoot(nullptr),
mParsingMode(aParsingMode),
mState(static_cast<State>(0)),
mInner(new StyleSheetInfo(aCORSMode, aIntegrity, aParsingMode)) {
mInner->AddSheet(this);
}
StyleSheet::StyleSheet(const StyleSheet& aCopy, StyleSheet* aParentSheetToUse,
dom::DocumentOrShadowRoot* aDocOrShadowRootToUse,
dom::Document* aConstructorDocToUse)
: mParentSheet(aParentSheetToUse),
mRelevantGlobal(nullptr),
mConstructorDocument(aConstructorDocToUse),
mTitle(aCopy.mTitle),
mDocumentOrShadowRoot(aDocOrShadowRootToUse),
mParsingMode(aCopy.mParsingMode),
mState(aCopy.mState),
// Shallow copy, but concrete subclasses will fix up.
mInner(aCopy.mInner) {
MOZ_ASSERT(!aConstructorDocToUse || aCopy.IsConstructed());
MOZ_ASSERT(!aConstructorDocToUse || !aDocOrShadowRootToUse,
"Should never have both of these together.");
MOZ_ASSERT(mInner, "Should only copy StyleSheets with an mInner.");
mInner->AddSheet(this);
// CSSOM's been there, force full copy now.
if (HasForcedUniqueInner()) {
MOZ_ASSERT(IsComplete(),
"Why have rules been accessed on an incomplete sheet?");
EnsureUniqueInner();
// But CSSOM hasn't been on _this_ stylesheet yet, so no need to clone
// ourselves.
mState &= ~(State::ForcedUniqueInner | State::ModifiedRules |
State::ModifiedRulesForDevtools);
}
if (aCopy.mMedia) {
// XXX This is wrong; we should be keeping @import rules and
// sheets in sync!
mMedia = aCopy.mMedia->Clone();
}
}
/* static */
// https://wicg.github.io/construct-stylesheets/#dom-cssstylesheet-cssstylesheet
already_AddRefed<StyleSheet> StyleSheet::Constructor(
const dom::GlobalObject& aGlobal, const dom::CSSStyleSheetInit& aOptions,
ErrorResult& aRv) {
nsCOMPtr<nsPIDOMWindowInner> window =
do_QueryInterface(aGlobal.GetAsSupports());
if (!window) {
aRv.ThrowNotSupportedError("Not supported when there is no document");
return nullptr;
}
Document* constructorDocument = window->GetExtantDoc();
if (!constructorDocument) {
aRv.ThrowNotSupportedError("Not supported when there is no document");
return nullptr;
}
// 1. Construct a sheet and set its properties (see spec).
auto sheet =
MakeRefPtr<StyleSheet>(css::SheetParsingMode::eAuthorSheetFeatures,
CORSMode::CORS_NONE, dom::SRIMetadata());
// baseURL not yet in the spec. Implemented based on the following discussion:
// https://github.com/WICG/construct-stylesheets/issues/95#issuecomment-594217180
RefPtr<nsIURI> baseURI;
if (!aOptions.mBaseURL.WasPassed()) {
baseURI = constructorDocument->GetBaseURI();
} else {
nsresult rv = NS_NewURI(getter_AddRefs(baseURI), aOptions.mBaseURL.Value(),
nullptr, constructorDocument->GetBaseURI());
if (NS_FAILED(rv)) {
aRv.ThrowNotAllowedError(
"Constructed style sheets must have a valid base URL");
return nullptr;
}
}
nsIURI* sheetURI = constructorDocument->GetDocumentURI();
nsIURI* originalURI = nullptr;
sheet->SetURIs(sheetURI, originalURI, baseURI);
sheet->SetPrincipal(constructorDocument->NodePrincipal());
sheet->SetReferrerInfo(constructorDocument->GetReferrerInfo());
sheet->mConstructorDocument = constructorDocument;
if (constructorDocument) {
sheet->mRelevantGlobal = constructorDocument->GetParentObject();
}
// 2. Set the sheet's media according to aOptions.
if (aOptions.mMedia.IsUTF8String()) {
sheet->SetMedia(MediaList::Create(aOptions.mMedia.GetAsUTF8String()));
} else {
sheet->SetMedia(aOptions.mMedia.GetAsMediaList()->Clone());
}
// 3. Set the sheet's disabled flag according to aOptions.
sheet->SetDisabled(aOptions.mDisabled);
sheet->SetComplete();
// 4. Return sheet.
return sheet.forget();
}
StyleSheet::~StyleSheet() {
MOZ_ASSERT(!mInner, "Inner should have been dropped in LastRelease");
}
bool StyleSheet::HasRules() const {
return Servo_StyleSheet_HasRules(Inner().mContents);
}
Document* StyleSheet::GetAssociatedDocument() const {
auto* associated = GetAssociatedDocumentOrShadowRoot();
return associated ? associated->AsNode().OwnerDoc() : nullptr;
}
dom::DocumentOrShadowRoot* StyleSheet::GetAssociatedDocumentOrShadowRoot()
const {
const StyleSheet& outer = OutermostSheet();
if (outer.mDocumentOrShadowRoot) {
return outer.mDocumentOrShadowRoot;
}
if (outer.IsConstructed()) {
return outer.mConstructorDocument;
}
return nullptr;
}
Document* StyleSheet::GetKeptAliveByDocument() const {
const StyleSheet& outer = OutermostSheet();
if (outer.mDocumentOrShadowRoot) {
return outer.mDocumentOrShadowRoot->AsNode().GetComposedDoc();
}
if (outer.IsConstructed()) {
for (DocumentOrShadowRoot* adopter : outer.mAdopters) {
MOZ_ASSERT(adopter->AsNode().OwnerDoc() == outer.mConstructorDocument);
if (adopter->AsNode().IsInComposedDoc()) {
return outer.mConstructorDocument.get();
}
}
}
return nullptr;
}
void StyleSheet::LastRelease() {
MOZ_DIAGNOSTIC_ASSERT(mAdopters.IsEmpty(),
"Should have no adopters at time of destruction.");
if (mInner) {
MOZ_ASSERT(mInner->mSheets.Contains(this), "Our mInner should include us.");
mInner->RemoveSheet(this);
mInner = nullptr;
}
DropMedia();
DropRuleList();
}
void StyleSheet::UnlinkInner() {
if (!mInner) {
return;
}
// We can only have a cycle through our inner if we have a unique inner,
// because otherwise there are no JS wrappers for anything in the inner.
if (mInner->mSheets.Length() != 1) {
mInner->RemoveSheet(this);
mInner = nullptr;
return;
}
for (StyleSheet* child : ChildSheets()) {
MOZ_ASSERT(child->mParentSheet == this, "We have a unique inner!");
child->mParentSheet = nullptr;
}
Inner().mChildren.Clear();
}
void StyleSheet::TraverseInner(nsCycleCollectionTraversalCallback& cb) {
if (!mInner) {
return;
}
for (StyleSheet* child : ChildSheets()) {
if (child->mParentSheet == this) {
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "child sheet");
cb.NoteXPCOMChild(child);
}
}
}
// QueryInterface implementation for StyleSheet
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(StyleSheet)
NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
NS_INTERFACE_MAP_ENTRY(nsICSSLoaderObserver)
NS_INTERFACE_MAP_ENTRY(nsISupports)
NS_INTERFACE_MAP_END
NS_IMPL_CYCLE_COLLECTING_ADDREF(StyleSheet)
// We want to disconnect from our inner as soon as our refcount drops to zero,
// without waiting for async deletion by the cycle collector. Otherwise we
// might end up cloning the inner if someone mutates another sheet that shares
// it with us, even though there is only one such sheet and we're about to go
// away. This situation arises easily with sheet preloading.
NS_IMPL_CYCLE_COLLECTING_RELEASE_WITH_LAST_RELEASE(StyleSheet, LastRelease())
NS_IMPL_CYCLE_COLLECTION_CLASS(StyleSheet)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(StyleSheet)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mMedia)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mRuleList)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mRelevantGlobal)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mConstructorDocument)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mReplacePromise)
tmp->TraverseInner(cb);
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(StyleSheet)
tmp->DropMedia();
tmp->UnlinkInner();
tmp->DropRuleList();
NS_IMPL_CYCLE_COLLECTION_UNLINK(mRelevantGlobal)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mConstructorDocument)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mReplacePromise)
NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRACE_WRAPPERCACHE(StyleSheet)
dom::CSSStyleSheetParsingMode StyleSheet::ParsingModeDOM() {
#define CHECK_MODE(X, Y) \
static_assert( \
static_cast<int>(X) == static_cast<int>(Y), \
"mozilla::dom::CSSStyleSheetParsingMode and " \
"mozilla::css::SheetParsingMode should have identical values");
CHECK_MODE(dom::CSSStyleSheetParsingMode::Agent, css::eAgentSheetFeatures);
CHECK_MODE(dom::CSSStyleSheetParsingMode::User, css::eUserSheetFeatures);
CHECK_MODE(dom::CSSStyleSheetParsingMode::Author, css::eAuthorSheetFeatures);
#undef CHECK_MODE
return static_cast<dom::CSSStyleSheetParsingMode>(mParsingMode);
}
void StyleSheet::SetComplete() {
// HasForcedUniqueInner() is okay if the sheet is constructed, because
// constructed sheets are always unique and they may be set to complete
// multiple times if their rules are replaced via Replace()
MOZ_ASSERT(IsConstructed() || !HasForcedUniqueInner(),
"Can't complete a sheet that's already been forced unique.");
MOZ_ASSERT(!IsComplete(), "Already complete?");
mState |= State::Complete;
if (!Disabled()) {
ApplicableStateChanged(true);
}
MaybeResolveReplacePromise();
}
void StyleSheet::ApplicableStateChanged(bool aApplicable) {
MOZ_ASSERT(aApplicable == IsApplicable());
auto Notify = [this](DocumentOrShadowRoot& target) {
nsINode& node = target.AsNode();
if (ShadowRoot* shadow = ShadowRoot::FromNode(node)) {
shadow->StyleSheetApplicableStateChanged(*this);
} else {
node.AsDocument()->StyleSheetApplicableStateChanged(*this);
}
};
const StyleSheet& sheet = OutermostSheet();
if (sheet.mDocumentOrShadowRoot) {
Notify(*sheet.mDocumentOrShadowRoot);
}
for (DocumentOrShadowRoot* adopter : sheet.mAdopters) {
MOZ_ASSERT(adopter, "adopters should never be null");
Notify(*adopter);
}
}
void StyleSheet::SetDisabled(bool aDisabled) {
if (IsReadOnly()) {
return;
}
if (aDisabled == Disabled()) {
return;
}
if (aDisabled) {
mState |= State::Disabled;
} else {
mState &= ~State::Disabled;
}
if (IsComplete()) {
ApplicableStateChanged(!aDisabled);
}
}
void StyleSheet::SetURLExtraData() {
Inner().mURLData =
new URLExtraData(GetBaseURI(), GetReferrerInfo(), Principal());
}
nsISupports* StyleSheet::GetRelevantGlobal() const {
const StyleSheet& outer = OutermostSheet();
return outer.mRelevantGlobal;
}
StyleSheetInfo::StyleSheetInfo(CORSMode aCORSMode,
const SRIMetadata& aIntegrity,
css::SheetParsingMode aParsingMode)
: mPrincipal(NullPrincipal::CreateWithoutOriginAttributes()),
mCORSMode(aCORSMode),
mReferrerInfo(new ReferrerInfo(nullptr)),
mIntegrity(aIntegrity),
mContents(Servo_StyleSheet_Empty(aParsingMode).Consume()),
mURLData(URLExtraData::Dummy())
#ifdef DEBUG
,
mPrincipalSet(false)
#endif
{
if (!mPrincipal) {
MOZ_CRASH("NullPrincipal::Init failed");
}
MOZ_COUNT_CTOR(StyleSheetInfo);
}
StyleSheetInfo::StyleSheetInfo(StyleSheetInfo& aCopy, StyleSheet* aPrimarySheet)
: mSheetURI(aCopy.mSheetURI),
mOriginalSheetURI(aCopy.mOriginalSheetURI),
mBaseURI(aCopy.mBaseURI),
mPrincipal(aCopy.mPrincipal),
mCORSMode(aCopy.mCORSMode),
mReferrerInfo(aCopy.mReferrerInfo),
mIntegrity(aCopy.mIntegrity),
// We don't rebuild the child because we're making a copy without
// children.
mSourceMapURL(aCopy.mSourceMapURL),
mSourceMapURLFromComment(aCopy.mSourceMapURLFromComment),
mSourceURL(aCopy.mSourceURL),
mContents(Servo_StyleSheet_Clone(aCopy.mContents.get(), aPrimarySheet)
.Consume()),
mURLData(aCopy.mURLData)
#ifdef DEBUG
,
mPrincipalSet(aCopy.mPrincipalSet)
#endif
{
AddSheet(aPrimarySheet);
// Our child list is fixed up by our parent.
MOZ_COUNT_CTOR(StyleSheetInfo);
}
StyleSheetInfo::~StyleSheetInfo() { MOZ_COUNT_DTOR(StyleSheetInfo); }
StyleSheetInfo* StyleSheetInfo::CloneFor(StyleSheet* aPrimarySheet) {
return new StyleSheetInfo(*this, aPrimarySheet);
}
MOZ_DEFINE_MALLOC_SIZE_OF(ServoStyleSheetMallocSizeOf)
MOZ_DEFINE_MALLOC_ENCLOSING_SIZE_OF(ServoStyleSheetMallocEnclosingSizeOf)
size_t StyleSheetInfo::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
size_t n = aMallocSizeOf(this);
n += Servo_StyleSheet_SizeOfIncludingThis(
ServoStyleSheetMallocSizeOf, ServoStyleSheetMallocEnclosingSizeOf,
mContents);
return n;
}
void StyleSheetInfo::AddSheet(StyleSheet* aSheet) {
mSheets.AppendElement(aSheet);
}
void StyleSheetInfo::RemoveSheet(StyleSheet* aSheet) {
// Fix up the parent pointer in children lists.
StyleSheet* newParent =
aSheet == mSheets[0] ? mSheets.SafeElementAt(1) : mSheets[0];
for (StyleSheet* child : mChildren) {
MOZ_ASSERT(child->mParentSheet);
MOZ_ASSERT(child->mParentSheet->mInner == this);
if (child->mParentSheet == aSheet) {
child->mParentSheet = newParent;
}
}
if (1 == mSheets.Length()) {
NS_ASSERTION(aSheet == mSheets.ElementAt(0), "bad parent");
delete this;
return;
}
mSheets.RemoveElement(aSheet);
}
void StyleSheet::GetType(nsAString& aType) { aType.AssignLiteral("text/css"); }
void StyleSheet::GetHref(nsAString& aHref, ErrorResult& aRv) {
if (nsIURI* sheetURI = Inner().mOriginalSheetURI) {
nsAutoCString str;
nsresult rv = sheetURI->GetSpec(str);
if (NS_FAILED(rv)) {
aRv.Throw(rv);
return;
}
CopyUTF8toUTF16(str, aHref);
} else {
SetDOMStringToNull(aHref);
}
}
void StyleSheet::GetTitle(nsAString& aTitle) {
// From https://drafts.csswg.org/cssom/#dom-stylesheet-title:
//
// The title attribute must return the title or null if title is the empty
// string.
//
if (!mTitle.IsEmpty()) {
aTitle.Assign(mTitle);
} else {
SetDOMStringToNull(aTitle);
}
}
void StyleSheet::WillDirty() {
MOZ_ASSERT(!IsReadOnly());
if (IsComplete()) {
EnsureUniqueInner();
}
}
void StyleSheet::AddStyleSet(ServoStyleSet* aStyleSet) {
MOZ_DIAGNOSTIC_ASSERT(!mStyleSets.Contains(aStyleSet),
"style set already registered");
mStyleSets.AppendElement(aStyleSet);
}
void StyleSheet::DropStyleSet(ServoStyleSet* aStyleSet) {
bool found = mStyleSets.RemoveElement(aStyleSet);
MOZ_DIAGNOSTIC_ASSERT(found, "didn't find style set");
#ifndef MOZ_DIAGNOSTIC_ASSERT_ENABLED
Unused << found;
#endif
}
// NOTE(emilio): Composed doc and containing shadow root are set in child sheets
// too, so no need to do it for each ancestor.
#define NOTIFY(function_, args_) \
do { \
StyleSheet* current = this; \
do { \
for (ServoStyleSet * set : current->mStyleSets) { \
set->function_ args_; \
} \
if (auto* docOrShadow = current->mDocumentOrShadowRoot) { \
if (auto* shadow = ShadowRoot::FromNode(docOrShadow->AsNode())) { \
shadow->function_ args_; \
} else { \
docOrShadow->AsNode().AsDocument()->function_ args_; \
} \
} \
for (auto* adopter : mAdopters) { \
if (auto* shadow = ShadowRoot::FromNode(adopter->AsNode())) { \
shadow->function_ args_; \
} else { \
adopter->AsNode().AsDocument()->function_ args_; \
} \
} \
current = current->mParentSheet; \
} while (current); \
} while (0)
void StyleSheet::EnsureUniqueInner() {
MOZ_ASSERT(mInner->mSheets.Length() != 0, "unexpected number of outers");
if (IsReadOnly()) {
// Sheets that can't be modified don't need a unique inner.
return;
}
mState |= State::ForcedUniqueInner;
if (HasUniqueInner()) {
// already unique
return;
}
StyleSheetInfo* clone = mInner->CloneFor(this);
MOZ_ASSERT(clone);
mInner->RemoveSheet(this);
mInner = clone;
// Fixup the child lists and parent links in the Servo sheet. This is done
// here instead of in StyleSheetInner::CloneFor, because it's just more
// convenient to do so instead.
FixUpAfterInnerClone();
// let our containing style sets know that if we call
// nsPresContext::EnsureSafeToHandOutCSSRules we will need to restyle the
// document
NOTIFY(SheetCloned, (*this));
}
// WebIDL CSSStyleSheet API
dom::CSSRuleList* StyleSheet::GetCssRules(nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv) {
if (!AreRulesAvailable(aSubjectPrincipal, aRv)) {
return nullptr;
}
return GetCssRulesInternal();
}
void StyleSheet::GetSourceMapURL(nsAString& aSourceMapURL) {
if (mInner->mSourceMapURL.IsEmpty()) {
aSourceMapURL = mInner->mSourceMapURLFromComment;
} else {
aSourceMapURL = mInner->mSourceMapURL;
}
}
void StyleSheet::SetSourceMapURL(const nsAString& aSourceMapURL) {
mInner->mSourceMapURL = aSourceMapURL;
}
void StyleSheet::SetSourceMapURLFromComment(
const nsAString& aSourceMapURLFromComment) {
mInner->mSourceMapURLFromComment = aSourceMapURLFromComment;
}
void StyleSheet::GetSourceURL(nsAString& aSourceURL) {
aSourceURL = mInner->mSourceURL;
}
void StyleSheet::SetSourceURL(const nsAString& aSourceURL) {
mInner->mSourceURL = aSourceURL;
}
css::Rule* StyleSheet::GetDOMOwnerRule() const { return GetOwnerRule(); }
// https://drafts.csswg.org/cssom/#dom-cssstylesheet-insertrule
// https://wicg.github.io/construct-stylesheets/#dom-cssstylesheet-insertrule
uint32_t StyleSheet::InsertRule(const nsACString& aRule, uint32_t aIndex,
nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv) {
if (IsReadOnly() || !AreRulesAvailable(aSubjectPrincipal, aRv)) {
return 0;
}
if (ModificationDisallowed()) {
aRv.ThrowNotAllowedError(
"This method can only be called on "
"modifiable style sheets");
return 0;
}
return InsertRuleInternal(aRule, aIndex, aRv);
}
// https://drafts.csswg.org/cssom/#dom-cssstylesheet-deleterule
// https://wicg.github.io/construct-stylesheets/#dom-cssstylesheet-deleterule
void StyleSheet::DeleteRule(uint32_t aIndex, nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv) {
if (IsReadOnly() || !AreRulesAvailable(aSubjectPrincipal, aRv)) {
return;
}
if (ModificationDisallowed()) {
return aRv.ThrowNotAllowedError(
"This method can only be called on "
"modifiable style sheets");
}
return DeleteRuleInternal(aIndex, aRv);
}
int32_t StyleSheet::AddRule(const nsACString& aSelector,
const nsACString& aBlock,
const Optional<uint32_t>& aIndex,
nsIPrincipal& aSubjectPrincipal, ErrorResult& aRv) {
if (IsReadOnly() || !AreRulesAvailable(aSubjectPrincipal, aRv)) {
return -1;
}
nsAutoCString rule;
rule.Append(aSelector);
rule.AppendLiteral(" { ");
if (!aBlock.IsEmpty()) {
rule.Append(aBlock);
rule.Append(' ');
}
rule.Append('}');
auto index =
aIndex.WasPassed() ? aIndex.Value() : GetCssRulesInternal()->Length();
InsertRuleInternal(rule, index, aRv);
// Always return -1.
return -1;
}
void StyleSheet::MaybeResolveReplacePromise() {
MOZ_ASSERT(!!mReplacePromise == ModificationDisallowed());
if (!mReplacePromise) {
return;
}
SetModificationDisallowed(false);
mReplacePromise->MaybeResolve(this);
mReplacePromise = nullptr;
}
void StyleSheet::MaybeRejectReplacePromise() {
MOZ_ASSERT(!!mReplacePromise == ModificationDisallowed());
if (!mReplacePromise) {
return;
}
SetModificationDisallowed(false);
mReplacePromise->MaybeRejectWithNetworkError(
"@import style sheet load failed");
mReplacePromise = nullptr;
}
// https://wicg.github.io/construct-stylesheets/#dom-cssstylesheet-replace
already_AddRefed<dom::Promise> StyleSheet::Replace(const nsACString& aText,
ErrorResult& aRv) {
nsIGlobalObject* globalObject = nullptr;
const StyleSheet& outer = OutermostSheet();
if (outer.mRelevantGlobal) {
globalObject = outer.mRelevantGlobal;
} else if (Document* doc = outer.GetAssociatedDocument()) {
globalObject = doc->GetScopeObject();
}
RefPtr<dom::Promise> promise = dom::Promise::Create(globalObject, aRv);
if (!promise) {
return nullptr;
}
// Step 1 and 4 are variable declarations
// 2.1 Check if sheet is constructed, else reject promise.
if (!IsConstructed()) {
promise->MaybeRejectWithNotAllowedError(
"This method can only be called on "
"constructed style sheets");
return promise.forget();
}
// 2.2 Check if sheet is modifiable, else throw.
if (ModificationDisallowed()) {
promise->MaybeRejectWithNotAllowedError(
"This method can only be called on "
"modifiable style sheets");
return promise.forget();
}
// 3. Disallow modifications until finished.
SetModificationDisallowed(true);
// TODO(emilio, 1642227): Should constructable stylesheets notify global
// observers (i.e., set mMustNotify to true)?
auto* loader = mConstructorDocument->CSSLoader();
auto loadData = MakeRefPtr<css::SheetLoadData>(
loader, nullptr, this, /* aSyncLoad */ false,
css::Loader::UseSystemPrincipal::No, css::StylePreloadKind::None,
/* aPreloadEncoding */ nullptr,
/* aObserver */ nullptr, mConstructorDocument->NodePrincipal(),
GetReferrerInfo(),
/* aRequestingNode */ nullptr);
// In parallel
// 5.1 Parse aText into rules.
// 5.2 Load import rules, throw NetworkError if failed.
// 5.3 Set sheet's rules to new rules.
nsCOMPtr<nsISerialEventTarget> target =
mConstructorDocument->EventTargetFor(TaskCategory::Other);
loadData->mIsBeingParsed = true;
MOZ_ASSERT(!mReplacePromise);
mReplacePromise = promise;
ParseSheet(*loader, aText, *loadData)
->Then(
target, __func__,
[loadData] { loadData->SheetFinishedParsingAsync(); },
[] { MOZ_CRASH("This MozPromise should never be rejected."); });
// 6. Return the promise
return promise.forget();
}
// https://wicg.github.io/construct-stylesheets/#dom-cssstylesheet-replacesync
void StyleSheet::ReplaceSync(const nsACString& aText, ErrorResult& aRv) {
// Step 1 is a variable declaration
// 2.1 Check if sheet is constructed, else throw.
if (!IsConstructed()) {
return aRv.ThrowNotAllowedError(
"Can only be called on constructed style sheets");
}
// 2.2 Check if sheet is modifiable, else throw.
if (ModificationDisallowed()) {
return aRv.ThrowNotAllowedError(
"Can only be called on modifiable style sheets");
}
// 3. Parse aText into rules.
// 4. If rules contain @imports, skip them and continue parsing.
auto* loader = mConstructorDocument->CSSLoader();
SetURLExtraData();
RefPtr<const RawServoStyleSheetContents> rawContent =
Servo_StyleSheet_FromUTF8Bytes(
loader, this,
/* load_data = */ nullptr, &aText, mParsingMode, Inner().mURLData,
/* line_number_offset = */ 0,
mConstructorDocument->GetCompatibilityMode(),
/* reusable_sheets = */ nullptr,
mConstructorDocument->GetStyleUseCounters(),
StyleAllowImportRules::No, StyleSanitizationKind::None,
/* sanitized_output = */ nullptr)
.Consume();
// 5. Set sheet's rules to the new rules.
DropRuleList();
Inner().mContents = std::move(rawContent);
FinishParse();
RuleChanged(nullptr, StyleRuleChangeKind::Generic);
}
nsresult StyleSheet::DeleteRuleFromGroup(css::GroupRule* aGroup,
uint32_t aIndex) {
NS_ENSURE_ARG_POINTER(aGroup);
NS_ASSERTION(IsComplete(), "No deleting from an incomplete sheet!");
RefPtr<css::Rule> rule = aGroup->GetStyleRuleAt(aIndex);
NS_ENSURE_TRUE(rule, NS_ERROR_ILLEGAL_VALUE);
// check that the rule actually belongs to this sheet!
if (this != rule->GetStyleSheet()) {
return NS_ERROR_INVALID_ARG;
}
if (IsReadOnly()) {
return NS_OK;
}
WillDirty();
nsresult result = aGroup->DeleteStyleRuleAt(aIndex);
NS_ENSURE_SUCCESS(result, result);
rule->DropReferences();
RuleRemoved(*rule);
return NS_OK;
}
void StyleSheet::RuleAdded(css::Rule& aRule) {
SetModifiedRules();
NOTIFY(RuleAdded, (*this, aRule));
}
void StyleSheet::RuleRemoved(css::Rule& aRule) {
SetModifiedRules();
NOTIFY(RuleRemoved, (*this, aRule));
}
void StyleSheet::RuleChanged(css::Rule* aRule, StyleRuleChangeKind aKind) {
MOZ_ASSERT(!aRule || HasUniqueInner(),
"Shouldn't have mutated a shared sheet");
SetModifiedRules();
NOTIFY(RuleChanged, (*this, aRule, aKind));
}
// nsICSSLoaderObserver implementation
NS_IMETHODIMP
StyleSheet::StyleSheetLoaded(StyleSheet* aSheet, bool aWasDeferred,
nsresult aStatus) {
if (!aSheet->GetParentSheet()) {
return NS_OK; // ignore if sheet has been detached already
}
MOZ_ASSERT(this == aSheet->GetParentSheet(),
"We are being notified of a sheet load for a sheet that is not "
"our child!");
if (NS_FAILED(aStatus)) {
return NS_OK;
}
MOZ_ASSERT(aSheet->GetOwnerRule());
NOTIFY(ImportRuleLoaded, (*aSheet->GetOwnerRule(), *aSheet));
return NS_OK;
}
#undef NOTIFY
nsresult StyleSheet::InsertRuleIntoGroup(const nsACString& aRule,
css::GroupRule* aGroup,
uint32_t aIndex) {
NS_ASSERTION(IsComplete(), "No inserting into an incomplete sheet!");
// check that the group actually belongs to this sheet!
if (this != aGroup->GetStyleSheet()) {
return NS_ERROR_INVALID_ARG;
}
if (IsReadOnly()) {
return NS_OK;
}
if (ModificationDisallowed()) {
return NS_ERROR_DOM_NOT_ALLOWED_ERR;
}
WillDirty();
nsresult result = InsertRuleIntoGroupInternal(aRule, aGroup, aIndex);
NS_ENSURE_SUCCESS(result, result);
RuleAdded(*aGroup->GetStyleRuleAt(aIndex));
return NS_OK;
}
uint64_t StyleSheet::FindOwningWindowInnerID() const {
uint64_t windowID = 0;
if (Document* doc = GetAssociatedDocument()) {
windowID = doc->InnerWindowID();
}
if (windowID == 0 && mOwningNode) {
windowID = mOwningNode->OwnerDoc()->InnerWindowID();
}
RefPtr<css::Rule> ownerRule;
if (windowID == 0 && (ownerRule = GetDOMOwnerRule())) {
RefPtr<StyleSheet> sheet = ownerRule->GetStyleSheet();
if (sheet) {
windowID = sheet->FindOwningWindowInnerID();
}
}
if (windowID == 0 && mParentSheet) {
windowID = mParentSheet->FindOwningWindowInnerID();
}
return windowID;
}
void StyleSheet::RemoveFromParent() {
if (!mParentSheet) {
return;
}
MOZ_ASSERT(mParentSheet->ChildSheets().Contains(this));
mParentSheet->Inner().mChildren.RemoveElement(this);
mParentSheet = nullptr;
}
void StyleSheet::SubjectSubsumesInnerPrincipal(nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv) {
StyleSheetInfo& info = Inner();
if (aSubjectPrincipal.Subsumes(info.mPrincipal)) {
return;
}
// Allow access only if CORS mode is not NONE and the security flag
// is not turned off.
if (GetCORSMode() == CORS_NONE && !nsContentUtils::BypassCSSOMOriginCheck()) {
aRv.ThrowSecurityError("Not allowed to access cross-origin stylesheet");
return;
}
// Now make sure we set the principal of our inner to the subjectPrincipal.
// We do this because we're in a situation where the caller would not normally
// be able to access the sheet, but the sheet has opted in to being read.
// Unfortunately, that means it's also opted in to being _edited_, and if the
// caller now makes edits to the sheet we want the resulting resource loads,
// if any, to look as if they are coming from the caller's principal, not the
// original sheet principal.
//
// That means we need a unique inner, of course. But we don't want to do that
// if we're not complete yet. Luckily, all the callers of this method throw
// anyway if not complete, so we can just do that here too.
if (!IsComplete()) {
aRv.ThrowInvalidAccessError(
"Not allowed to access still-loading stylesheet");
return;
}
WillDirty();
info.mPrincipal = &aSubjectPrincipal;
}
bool StyleSheet::AreRulesAvailable(nsIPrincipal& aSubjectPrincipal,
ErrorResult& aRv) {
// Rules are not available on incomplete sheets.
if (!IsComplete()) {
aRv.ThrowInvalidAccessError(
"Can't access rules of still-loading style sheet");
return false;
}
//-- Security check: Only scripts whose principal subsumes that of the
// style sheet can access rule collections.
SubjectSubsumesInnerPrincipal(aSubjectPrincipal, aRv);
if (NS_WARN_IF(aRv.Failed())) {
return false;
}
return true;
}
void StyleSheet::SetAssociatedDocumentOrShadowRoot(
DocumentOrShadowRoot* aDocOrShadowRoot) {
MOZ_ASSERT(!IsConstructed());
MOZ_ASSERT(!mParentSheet || !aDocOrShadowRoot,
"Shouldn't be set on child sheets");
// not ref counted
mDocumentOrShadowRoot = aDocOrShadowRoot;
if (Document* doc = GetAssociatedDocument()) {
MOZ_ASSERT(!mRelevantGlobal);
mRelevantGlobal = doc->GetScopeObject();
}
}
void StyleSheet::AppendStyleSheet(StyleSheet& aSheet) {
WillDirty();
AppendStyleSheetSilently(aSheet);
}
void StyleSheet::AppendStyleSheetSilently(StyleSheet& aSheet) {
MOZ_ASSERT(!IsReadOnly());
Inner().mChildren.AppendElement(&aSheet);
// This is not reference counted. Our parent tells us when
// it's going away.
aSheet.mParentSheet = this;
}
size_t StyleSheet::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
size_t n = 0;
n += aMallocSizeOf(this);
// We want to measure the inner with only one of the children, and it makes
// sense for it to be the latest as it is the most likely to be reachable.
if (Inner().mSheets.LastElement() == this) {
n += Inner().SizeOfIncludingThis(aMallocSizeOf);
}
// Measurement of the following members may be added later if DMD finds it
// is worthwhile:
// - mTitle
// - mMedia
// - mStyleSets
// - mRuleList
return n;
}
#if defined(DEBUG) || defined(MOZ_LAYOUT_DEBUGGER)
void StyleSheet::List(FILE* aOut, int32_t aIndent) {
for (StyleSheet* child : ChildSheets()) {
child->List(aOut, aIndent);
}
nsCString line;
for (int i = 0; i < aIndent; ++i) {
line.AppendLiteral(" ");
}
line.AppendLiteral("/* ");
nsCString url;
GetSheetURI()->GetSpec(url);
if (url.IsEmpty()) {
line.AppendLiteral("(no URL)");
} else {
line.Append(url);
}
line.AppendLiteral(" (");
switch (GetOrigin()) {
case StyleOrigin::UserAgent:
line.AppendLiteral("User Agent");
break;
case StyleOrigin::User:
line.AppendLiteral("User");
break;
case StyleOrigin::Author:
line.AppendLiteral("Author");
break;
}
if (mMedia) {
nsAutoCString buffer;
mMedia->GetText(buffer);
if (!buffer.IsEmpty()) {
line.AppendLiteral(", ");
line.Append(buffer);
}
}
line.AppendLiteral(") */");
fprintf_stderr(aOut, "%s\n\n", line.get());
nsCString newlineIndent;
newlineIndent.Append('\n');
for (int i = 0; i < aIndent; ++i) {
newlineIndent.AppendLiteral(" ");
}
ServoCSSRuleList* ruleList = GetCssRulesInternal();
for (uint32_t i = 0, len = ruleList->Length(); i < len; ++i) {
css::Rule* rule = ruleList->GetRule(i);
nsAutoCString cssText;
rule->GetCssText(cssText);
cssText.ReplaceSubstring("\n"_ns, newlineIndent);
fprintf_stderr(aOut, "%s\n", cssText.get());
}
if (ruleList->Length() != 0) {
fprintf_stderr(aOut, "\n");
}
}
#endif
void StyleSheet::SetMedia(already_AddRefed<dom::MediaList> aMedia) {
mMedia = aMedia;
if (mMedia) {
mMedia->SetStyleSheet(this);
}
}
void StyleSheet::DropMedia() {
if (mMedia) {
mMedia->SetStyleSheet(nullptr);
mMedia = nullptr;
}
}
dom::MediaList* StyleSheet::Media() {
if (!mMedia) {
mMedia = dom::MediaList::Create(EmptyCString());
mMedia->SetStyleSheet(this);
}
return mMedia;
}
// nsWrapperCache
JSObject* StyleSheet::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return dom::CSSStyleSheet_Binding::Wrap(aCx, this, aGivenProto);
}
void StyleSheet::FixUpAfterInnerClone() {
MOZ_ASSERT(Inner().mSheets.Length() == 1, "Should've just cloned");
MOZ_ASSERT(Inner().mSheets[0] == this);
MOZ_ASSERT(Inner().mChildren.IsEmpty());
auto* contents = Inner().mContents.get();
RefPtr<ServoCssRules> rules = Servo_StyleSheet_GetRules(contents).Consume();
if (mRuleList) {
mRuleList->SetRawAfterClone(rules);
}
uint32_t index = 0;
while (true) {
uint32_t line, column; // Actually unused.
RefPtr<RawServoImportRule> import =
Servo_CssRules_GetImportRuleAt(rules, index, &line, &column).Consume();
if (!import) {
// Note that only @charset rules come before @import rules, and @charset
// rules are parsed but skipped, so we can stop iterating as soon as we
// find something that isn't an @import rule.
break;
}
auto* sheet = const_cast<StyleSheet*>(Servo_ImportRule_GetSheet(import));
MOZ_ASSERT(sheet);
AppendStyleSheetSilently(*sheet);
index++;
}
}
already_AddRefed<StyleSheet> StyleSheet::CreateEmptyChildSheet(
already_AddRefed<dom::MediaList> aMediaList) const {
RefPtr<StyleSheet> child =
new StyleSheet(ParsingMode(), CORSMode::CORS_NONE, SRIMetadata());
child->mMedia = aMediaList;
return child.forget();
}
// We disable parallel stylesheet parsing if any of the following three
// conditions hold:
//
// (1) The pref is off.
// (2) The browser is recording CSS errors (which parallel parsing can't
// handle).
// (3) The stylesheet is a chrome stylesheet, since those can use
// -moz-bool-pref, which needs to access the pref service, which is not
// threadsafe.
static bool AllowParallelParse(css::Loader& aLoader, URLExtraData* aUrlData) {
// If the browser is recording CSS errors, we need to use the sequential path
// because the parallel path doesn't support that.
Document* doc = aLoader.GetDocument();
if (doc && css::ErrorReporter::ShouldReportErrors(*doc)) {
return false;
}
// If this is a chrome stylesheet, it might use -moz-bool-pref, which needs to
// access the pref service, which is not thread-safe. We could probably expose
// the relevant booleans as thread-safe var caches if we needed to, but
// parsing chrome stylesheets in parallel is unlikely to be a win anyway.
//
// Note that UA stylesheets can also use -moz-bool-pref, but those are always
// parsed sync.
if (aUrlData->ChromeRulesEnabled()) {
return false;
}
return true;
}
RefPtr<StyleSheetParsePromise> StyleSheet::ParseSheet(
css::Loader& aLoader, const nsACString& aBytes,
css::SheetLoadData& aLoadData) {
MOZ_ASSERT(mParsePromise.IsEmpty());
RefPtr<StyleSheetParsePromise> p = mParsePromise.Ensure(__func__);
SetURLExtraData();
// @import rules are disallowed due to this decision:
// https://github.com/WICG/construct-stylesheets/issues/119#issuecomment-588352418
// We may allow @import rules again in the future.
auto allowImportRules = SelfOrAncestorIsConstructed()
? StyleAllowImportRules::No
: StyleAllowImportRules::Yes;
const bool shouldRecordCounters =
aLoader.GetDocument() && aLoader.GetDocument()->GetStyleUseCounters();
if (!AllowParallelParse(aLoader, Inner().mURLData)) {
UniquePtr<StyleUseCounters> counters =
shouldRecordCounters ? Servo_UseCounters_Create().Consume() : nullptr;
RefPtr<RawServoStyleSheetContents> contents =
Servo_StyleSheet_FromUTF8Bytes(
&aLoader, this, &aLoadData, &aBytes, mParsingMode, Inner().mURLData,
aLoadData.mLineNumber, aLoadData.mCompatMode,
/* reusable_sheets = */ nullptr, counters.get(), allowImportRules,
StyleSanitizationKind::None,
/* sanitized_output = */ nullptr)
.Consume();
aLoadData.mUseCounters = std::move(counters);
FinishAsyncParse(contents.forget());
} else {
auto holder = MakeRefPtr<css::SheetLoadDataHolder>(__func__, &aLoadData);
Servo_StyleSheet_FromUTF8BytesAsync(
holder, Inner().mURLData, &aBytes, mParsingMode, aLoadData.mLineNumber,
aLoadData.mCompatMode, shouldRecordCounters, allowImportRules);
}
return p;
}
void StyleSheet::FinishAsyncParse(
already_AddRefed<RawServoStyleSheetContents> aSheetContents) {
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(!mParsePromise.IsEmpty());
Inner().mContents = aSheetContents;
FinishParse();
mParsePromise.Resolve(true, __func__);
}
void StyleSheet::ParseSheetSync(
css::Loader* aLoader, const nsACString& aBytes,
css::SheetLoadData* aLoadData, uint32_t aLineNumber,
css::LoaderReusableStyleSheets* aReusableSheets) {
const nsCompatibility compatMode = [&] {
if (aLoadData) {
return aLoadData->mCompatMode;
}
if (aLoader) {
return aLoader->CompatMode(css::StylePreloadKind::None);
}
return eCompatibility_FullStandards;
}();
const StyleUseCounters* useCounters =
aLoader && aLoader->GetDocument()
? aLoader->GetDocument()->GetStyleUseCounters()
: nullptr;
auto allowImportRules = SelfOrAncestorIsConstructed()
? StyleAllowImportRules::No
: StyleAllowImportRules::Yes;
SetURLExtraData();
Inner().mContents =
Servo_StyleSheet_FromUTF8Bytes(
aLoader, this, aLoadData, &aBytes, mParsingMode, Inner().mURLData,
aLineNumber, compatMode, aReusableSheets, useCounters,
allowImportRules, StyleSanitizationKind::None,
/* sanitized_output = */ nullptr)
.Consume();
FinishParse();
}
void StyleSheet::FinishParse() {
nsString sourceMapURL;
Servo_StyleSheet_GetSourceMapURL(Inner().mContents, &sourceMapURL);
SetSourceMapURLFromComment(sourceMapURL);
nsString sourceURL;
Servo_StyleSheet_GetSourceURL(Inner().mContents, &sourceURL);
SetSourceURL(sourceURL);
}
void StyleSheet::ReparseSheet(const nsACString& aInput, ErrorResult& aRv) {
if (!IsComplete()) {
return aRv.ThrowInvalidAccessError("Cannot reparse still-loading sheet");
}
// Allowing to modify UA sheets is dangerous (in the sense that C++ code
// relies on rules in those sheets), plus they're probably going to be shared
// across processes in which case this is directly a no-go.
if (IsReadOnly()) {
return;
}
// Hold strong ref to the CSSLoader in case the document update
// kills the document
RefPtr<css::Loader> loader;
if (Document* doc = GetAssociatedDocument()) {
loader = doc->CSSLoader();
NS_ASSERTION(loader, "Document with no CSS loader!");
} else {
loader = new css::Loader;
}
WillDirty();
// cache child sheets to reuse
css::LoaderReusableStyleSheets reusableSheets;
for (StyleSheet* child : ChildSheets()) {
if (child->GetOriginalURI()) {
reusableSheets.AddReusableSheet(child);
}
}
// Clean up child sheets list.
for (StyleSheet* child : ChildSheets()) {
child->mParentSheet = nullptr;
}
Inner().mChildren.Clear();
uint32_t lineNumber = 1;
if (auto* linkStyle = LinkStyle::FromNodeOrNull(mOwningNode)) {
lineNumber = linkStyle->GetLineNumber();
}
// Notify to the stylesets about the old rules going away.
{
ServoCSSRuleList* ruleList = GetCssRulesInternal();
MOZ_ASSERT(ruleList);
uint32_t ruleCount = ruleList->Length();
for (uint32_t i = 0; i < ruleCount; ++i) {
css::Rule* rule = ruleList->GetRule(i);
MOZ_ASSERT(rule);
RuleRemoved(*rule);
}
}
DropRuleList();
ParseSheetSync(loader, aInput, /* aLoadData = */ nullptr, lineNumber,
&reusableSheets);
// Notify the stylesets about the new rules.
{
// Get the rule list (which will need to be regenerated after ParseSheet).
ServoCSSRuleList* ruleList = GetCssRulesInternal();
MOZ_ASSERT(ruleList);
uint32_t ruleCount = ruleList->Length();
for (uint32_t i = 0; i < ruleCount; ++i) {
css::Rule* rule = ruleList->GetRule(i);
MOZ_ASSERT(rule);
RuleAdded(*rule);
}
}
// Our rules are no longer considered modified for devtools.
mState &= ~State::ModifiedRulesForDevtools;
}
void StyleSheet::DropRuleList() {
if (mRuleList) {
mRuleList->DropReferences();
mRuleList = nullptr;
}
}
already_AddRefed<StyleSheet> StyleSheet::Clone(
StyleSheet* aCloneParent,
dom::DocumentOrShadowRoot* aCloneDocumentOrShadowRoot) const {
MOZ_ASSERT(!IsConstructed(),
"Cannot create a non-constructed sheet from a constructed sheet");
RefPtr<StyleSheet> clone =
new StyleSheet(*this, aCloneParent, aCloneDocumentOrShadowRoot,
/* aConstructorDocToUse */ nullptr);
return clone.forget();
}
already_AddRefed<StyleSheet> StyleSheet::CloneAdoptedSheet(
Document& aConstructorDocument) const {
MOZ_ASSERT(IsConstructed(),
"Cannot create a constructed sheet from a non-constructed sheet");
MOZ_ASSERT(aConstructorDocument.IsStaticDocument(),
"Should never clone adopted sheets for a non-static document");
RefPtr<StyleSheet> clone = new StyleSheet(*this,
/* aParentSheetToUse */ nullptr,
/* aDocOrShadowRootToUse */ nullptr,
&aConstructorDocument);
return clone.forget();
}
ServoCSSRuleList* StyleSheet::GetCssRulesInternal() {
if (!mRuleList) {
RefPtr<ServoCssRules> rawRules =
Servo_StyleSheet_GetRules(Inner().mContents).Consume();
MOZ_ASSERT(rawRules);
mRuleList = new ServoCSSRuleList(rawRules.forget(), this, nullptr);
}
return mRuleList;
}
uint32_t StyleSheet::InsertRuleInternal(const nsACString& aRule,
uint32_t aIndex, ErrorResult& aRv) {
MOZ_ASSERT(!IsReadOnly());
MOZ_ASSERT(!ModificationDisallowed());
// Ensure mRuleList is constructed.
GetCssRulesInternal();
aRv = mRuleList->InsertRule(aRule, aIndex);
if (aRv.Failed()) {
return 0;
}
// XXX We may not want to get the rule when stylesheet change event
// is not enabled.
css::Rule* rule = mRuleList->GetRule(aIndex);
RuleAdded(*rule);
return aIndex;
}
void StyleSheet::DeleteRuleInternal(uint32_t aIndex, ErrorResult& aRv) {
MOZ_ASSERT(!IsReadOnly());
MOZ_ASSERT(!ModificationDisallowed());
// Ensure mRuleList is constructed.
GetCssRulesInternal();
if (aIndex >= mRuleList->Length()) {
aRv.ThrowIndexSizeError(
nsPrintfCString("Cannot delete rule at index %u"
" because the number of rules is only %u",
aIndex, mRuleList->Length()));
return;
}
// Hold a strong ref to the rule so it doesn't die when we remove it
// from the list. XXX We may not want to hold it if stylesheet change
// event is not enabled.
RefPtr<css::Rule> rule = mRuleList->GetRule(aIndex);
aRv = mRuleList->DeleteRule(aIndex);
if (!aRv.Failed()) {
RuleRemoved(*rule);
}
}
nsresult StyleSheet::InsertRuleIntoGroupInternal(const nsACString& aRule,
css::GroupRule* aGroup,
uint32_t aIndex) {
MOZ_ASSERT(!IsReadOnly());
auto rules = static_cast<ServoCSSRuleList*>(aGroup->CssRules());
MOZ_ASSERT(rules->GetParentRule() == aGroup);
return rules->InsertRule(aRule, aIndex);
}
StyleOrigin StyleSheet::GetOrigin() const {
return Servo_StyleSheet_GetOrigin(Inner().mContents);
}
void StyleSheet::SetSharedContents(const ServoCssRules* aSharedRules) {
MOZ_ASSERT(!IsComplete());
SetURLExtraData();
Inner().mContents =
Servo_StyleSheet_FromSharedData(Inner().mURLData, aSharedRules).Consume();
// Don't call FinishParse(), since that tries to set source map URLs,
// which we don't have.
}
const ServoCssRules* StyleSheet::ToShared(RawServoSharedMemoryBuilder* aBuilder,
nsCString& aErrorMessage) {
// Assert some things we assume when creating a StyleSheet using shared
// memory.
MOZ_ASSERT(GetReferrerInfo()->ReferrerPolicy() == ReferrerPolicy::_empty);
MOZ_ASSERT(GetReferrerInfo()->GetSendReferrer());
MOZ_ASSERT(!nsCOMPtr<nsIURI>(GetReferrerInfo()->GetComputedReferrer()));
MOZ_ASSERT(GetCORSMode() == CORS_NONE);
MOZ_ASSERT(Inner().mIntegrity.IsEmpty());
MOZ_ASSERT(Principal()->IsSystemPrincipal());
const ServoCssRules* rules = Servo_SharedMemoryBuilder_AddStylesheet(
aBuilder, Inner().mContents, &aErrorMessage);
#ifdef DEBUG
if (!rules) {
// Print the ToShmem error message so that developers know what to fix.
printf_stderr("%s\n", aErrorMessage.get());
MOZ_CRASH("UA style sheet contents failed shared memory requirements");
}
#endif
return rules;
}
bool StyleSheet::IsReadOnly() const {
return IsComplete() && GetOrigin() == StyleOrigin::UserAgent;
}
} // namespace mozilla