diff options
Diffstat (limited to 'layout/style/StyleSheet.cpp')
| -rw-r--r-- | layout/style/StyleSheet.cpp | 1484 |
1 files changed, 1484 insertions, 0 deletions
diff --git a/layout/style/StyleSheet.cpp b/layout/style/StyleSheet.cpp new file mode 100644 index 0000000000..494618d879 --- /dev/null +++ b/layout/style/StyleSheet.cpp @@ -0,0 +1,1484 @@ +/* -*- 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/FetchPriority.h" +#include "mozilla/dom/MediaList.h" +#include "mozilla/dom/Promise.h" +#include "mozilla/dom/ReferrerInfo.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), + 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), + 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()); + auto referrerInfo = MakeRefPtr<ReferrerInfo>(*constructorDocument); + sheet->SetReferrerInfo(referrerInfo); + sheet->mConstructorDocument = constructorDocument; + + // 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; +} + +void StyleSheet::UpdateRelevantGlobal() { + if (mRelevantGlobal || !IsComplete()) { + return; + } + if (Document* doc = GetAssociatedDocument()) { + mRelevantGlobal = doc->GetScopeObject(); + } +} + +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_WRAPPERCACHE_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 + +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; + + UpdateRelevantGlobal(); + + if (!Disabled()) { + ApplicableStateChanged(true); + } + MaybeResolveReplacePromise(); +} + +void StyleSheet::ApplicableStateChanged(bool aApplicable) { + MOZ_ASSERT(aApplicable == IsApplicable()); + Document* docToPostEvent = nullptr; + auto Notify = [&](DocumentOrShadowRoot& target) { + nsINode& node = target.AsNode(); + if (ShadowRoot* shadow = ShadowRoot::FromNode(node)) { + shadow->StyleSheetApplicableStateChanged(*this); + MOZ_ASSERT(!docToPostEvent || !shadow->IsInComposedDoc() || + docToPostEvent == shadow->GetComposedDoc()); + if (!docToPostEvent) { + docToPostEvent = shadow->GetComposedDoc(); + } + } else { + Document* doc = node.AsDocument(); + MOZ_ASSERT(!docToPostEvent || docToPostEvent == doc); + doc->StyleSheetApplicableStateChanged(*this); + docToPostEvent = doc; + } + }; + + const StyleSheet& sheet = OutermostSheet(); + if (sheet.mDocumentOrShadowRoot) { + Notify(*sheet.mDocumentOrShadowRoot); + } + + if (sheet.mConstructorDocument) { + Notify(*sheet.mConstructorDocument); + } + + for (DocumentOrShadowRoot* adopter : sheet.mAdopters) { + MOZ_ASSERT(adopter, "adopters should never be null"); + if (adopter != sheet.mConstructorDocument) { + Notify(*adopter); + } + } + + if (docToPostEvent) { + docToPostEvent->PostStyleSheetApplicableStateChangeEvent(*this); + } +} + +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()) { + 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), + 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(nsACString& aSourceMapURL) { + if (!mInner->mSourceMapURL.IsEmpty()) { + aSourceMapURL = mInner->mSourceMapURL; + return; + } + Servo_StyleSheet_GetSourceMapURL(mInner->mContents, &aSourceMapURL); +} + +void StyleSheet::SetSourceMapURL(nsCString&& aSourceMapURL) { + mInner->mSourceMapURL = std::move(aSourceMapURL); +} + +void StyleSheet::GetSourceURL(nsACString& aSourceURL) { + Servo_StyleSheet_GetSourceURL(mInner->mContents, &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://drafts.csswg.org/cssom/#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, /* aURI = */ nullptr, this, css::SyncLoad::No, + css::Loader::UseSystemPrincipal::No, css::StylePreloadKind::None, + /* aPreloadEncoding */ nullptr, /* aObserver */ nullptr, + mConstructorDocument->NodePrincipal(), GetReferrerInfo(), + /* aNonce */ u""_ns, FetchPriority::Auto); + + // 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. + nsISerialEventTarget* target = GetMainThreadSerialEventTarget(); + 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 StyleStylesheetContents> rawContent = + Servo_StyleSheet_FromUTF8Bytes( + loader, this, + /* load_data = */ nullptr, &aText, mParsingMode, URLData(), + mConstructorDocument->GetCompatibilityMode(), + /* reusable_sheets = */ nullptr, + mConstructorDocument->GetStyleUseCounters(), + StyleAllowImportRules::No, StyleSanitizationKind::None, + /* sanitized_output = */ nullptr) + .Consume(); + + // 5. Set sheet's rules to the new rules. + Inner().mContents = std::move(rawContent); + FixUpRuleListAfterContentsChangeIfNeeded(); + 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; + UpdateRelevantGlobal(); +} + +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::FixUpRuleListAfterContentsChangeIfNeeded(bool aFromClone) { + if (!mRuleList) { + return; + } + + RefPtr<StyleLockedCssRules> rules = + Servo_StyleSheet_GetRules(Inner().mContents.get()).Consume(); + mRuleList->SetRawContents(std::move(rules), aFromClone); +} + +void StyleSheet::FixUpAfterInnerClone() { + MOZ_ASSERT(Inner().mSheets.Length() == 1, "Should've just cloned"); + MOZ_ASSERT(Inner().mSheets[0] == this); + MOZ_ASSERT(Inner().mChildren.IsEmpty()); + + FixUpRuleListAfterContentsChangeIfNeeded(/* aFromClone = */ true); + + RefPtr<StyleLockedCssRules> rules = + Servo_StyleSheet_GetRules(Inner().mContents.get()).Consume(); + uint32_t index = 0; + while (true) { + uint32_t line, column; // Actually unused. + RefPtr<StyleLockedImportRule> 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 the browser is recording CSS errors +// (which parallel parsing can't handle). +static bool AllowParallelParse(css::Loader& aLoader, URLExtraData* aUrlData) { + Document* doc = aLoader.GetDocument(); + if (doc && css::ErrorReporter::ShouldReportErrors(*doc)) { + return false; + } + // Otherwise we can parse in parallel. + 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__); + if (!aLoadData.ShouldDefer()) { + mParsePromise.SetTaskPriority(nsIRunnablePriority::PRIORITY_RENDER_BLOCKING, + __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; + URLExtraData* urlData = URLData(); + const bool shouldRecordCounters = + aLoader.GetDocument() && aLoader.GetDocument()->GetStyleUseCounters() && + !urlData->ChromeRulesEnabled(); + if (!AllowParallelParse(aLoader, urlData)) { + UniquePtr<StyleUseCounters> counters; + if (shouldRecordCounters) { + counters.reset(Servo_UseCounters_Create()); + } + + RefPtr<StyleStylesheetContents> contents = + Servo_StyleSheet_FromUTF8Bytes( + &aLoader, this, &aLoadData, &aBytes, mParsingMode, urlData, + aLoadData.mCompatMode, + /* reusable_sheets = */ nullptr, counters.get(), allowImportRules, + StyleSanitizationKind::None, + /* sanitized_output = */ nullptr) + .Consume(); + FinishAsyncParse(contents.forget(), std::move(counters)); + } else { + auto holder = MakeRefPtr<css::SheetLoadDataHolder>(__func__, &aLoadData); + Servo_StyleSheet_FromUTF8BytesAsync(holder, urlData, &aBytes, mParsingMode, + aLoadData.mCompatMode, + shouldRecordCounters, allowImportRules); + } + + return p; +} + +void StyleSheet::FinishAsyncParse( + already_AddRefed<StyleStylesheetContents> aSheetContents, + UniquePtr<StyleUseCounters> aUseCounters) { + MOZ_ASSERT(NS_IsMainThread()); + MOZ_ASSERT(!mParsePromise.IsEmpty()); + Inner().mContents = aSheetContents; + Inner().mUseCounters = std::move(aUseCounters); + FixUpRuleListAfterContentsChangeIfNeeded(); + mParsePromise.Resolve(true, __func__); +} + +void StyleSheet::ParseSheetSync( + css::Loader* aLoader, const nsACString& aBytes, + css::SheetLoadData* aLoadData, + css::LoaderReusableStyleSheets* aReusableSheets) { + const nsCompatibility compatMode = [&] { + if (aLoadData) { + return aLoadData->mCompatMode; + } + if (aLoader) { + return aLoader->CompatMode(css::StylePreloadKind::None); + } + return eCompatibility_FullStandards; + }(); + + SetURLExtraData(); + + URLExtraData* urlData = URLData(); + const StyleUseCounters* useCounters = + aLoader && aLoader->GetDocument() && !urlData->ChromeRulesEnabled() + ? aLoader->GetDocument()->GetStyleUseCounters() + : nullptr; + + auto allowImportRules = SelfOrAncestorIsConstructed() + ? StyleAllowImportRules::No + : StyleAllowImportRules::Yes; + + Inner().mContents = Servo_StyleSheet_FromUTF8Bytes( + aLoader, this, aLoadData, &aBytes, mParsingMode, + urlData, compatMode, aReusableSheets, useCounters, + allowImportRules, StyleSanitizationKind::None, + /* sanitized_output = */ nullptr) + .Consume(); +} + +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(); + + // 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); + } + + // We need to clear the rule list here (rather than after parsing) because + // ParseSheetSync may reuse child sheets, which would cause us to end up + // with a wrong mChilden array. + ruleList->SetRawContents(nullptr, /* aFromClone = */ false); + } + + ParseSheetSync(loader, aInput, /* aLoadData = */ nullptr, &reusableSheets); + + FixUpRuleListAfterContentsChangeIfNeeded(); + + // 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) { + // TODO(emilio): This should go away, but we need to fix the CC setup for + // @import rules first, see bug 1719963. + EnsureUniqueInner(); + + RefPtr<StyleLockedCssRules> 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()); + + ServoCSSRuleList* rules = aGroup->CssRules(); + MOZ_ASSERT(rules && rules->GetParentRule() == aGroup); + return rules->InsertRule(aRule, aIndex); +} + +StyleOrigin StyleSheet::GetOrigin() const { + return Servo_StyleSheet_GetOrigin(Inner().mContents); +} + +void StyleSheet::SetSharedContents(const StyleLockedCssRules* aSharedRules) { + MOZ_ASSERT(!IsComplete()); + + SetURLExtraData(); + + Inner().mContents = + Servo_StyleSheet_FromSharedData(URLData(), aSharedRules).Consume(); +} + +const StyleLockedCssRules* StyleSheet::ToShared( + StyleSharedMemoryBuilder* 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 StyleLockedCssRules* 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 |