Files
ladybird/Libraries/LibWeb/CSS/CSSStyleSheet.h
Andreas Kling caad205467 LibWeb: Share singleton constructed stylesheet rule caches
Share the style cache for shadow roots whose only active author sheet is
the same constructed stylesheet. Matching already carries the effective
shadow root separately, so the cache can be reused while selectors such
as :host and ::slotted() still evaluate against each consuming shadow
root.

Keep the optimization conservative by falling back to the existing
per-scope cache whenever the shadow root has multiple active sheets, a
non-constructed sheet, or a page user stylesheet. Drop the shared cache
when the stylesheet rules or media query match state change.

Add coverage for two shadow roots adopting the same constructed sheet,
including :host, ::slotted(), and replaceSync() invalidation.
2026-04-28 13:07:52 +02:00

172 lines
6.7 KiB
C++

/*
* Copyright (c) 2019-2021, Andreas Kling <andreas@ladybird.org>
* Copyright (c) 2024, Tim Ledbetter <timledbetter@gmail.com>
* Copyright (c) 2026, Sam Atkins <sam@ladybird.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Function.h>
#include <AK/NonnullRefPtr.h>
#include <AK/RefPtr.h>
#include <LibWeb/CSS/CSSNamespaceRule.h>
#include <LibWeb/CSS/CSSRule.h>
#include <LibWeb/CSS/CSSRuleList.h>
#include <LibWeb/CSS/CSSStyleRule.h>
#include <LibWeb/CSS/StyleSheet.h>
#include <LibWeb/CSS/StyleValues/ImageStyleValue.h>
#include <LibWeb/DOM/StyleInvalidationReason.h>
#include <LibWeb/Export.h>
#include <LibWeb/WebIDL/Types.h>
namespace Web::CSS {
class CSSImportRule;
class StyleScope;
struct ShadowRootStylesheetEffects;
struct StyleCache;
struct CSSStyleSheetInit {
Optional<String> base_url {};
Variant<GC::Root<MediaList>, String> media { String {} };
bool disabled { false };
};
// https://drafts.csswg.org/cssom-1/#cssstylesheet
class WEB_API CSSStyleSheet final : public StyleSheet {
WEB_PLATFORM_OBJECT(CSSStyleSheet, StyleSheet);
GC_DECLARE_ALLOCATOR(CSSStyleSheet);
public:
enum class LoadingState : u8 {
Unloaded,
Loading,
Loaded,
Error,
};
static StringView loading_state_name(LoadingState);
class Subresource {
public:
virtual ~Subresource() = default;
virtual GC::Ptr<CSSStyleSheet> parent_style_sheet_for_subresource() = 0;
LoadingState loading_state() const { return m_loading_state; }
virtual void visit_edges(Cell::Visitor&) = 0;
void set_loading_state(LoadingState);
private:
LoadingState m_loading_state { LoadingState::Unloaded };
};
[[nodiscard]] static GC::Ref<CSSStyleSheet> create(JS::Realm&, CSSRuleList&, MediaList&, Optional<::URL::URL> location);
static WebIDL::ExceptionOr<GC::Ref<CSSStyleSheet>> construct_impl(JS::Realm&, Optional<CSSStyleSheetInit> const& options = {});
virtual ~CSSStyleSheet() override;
GC::Ptr<CSSRule const> owner_rule() const { return m_owner_css_rule; }
GC::Ptr<CSSRule> owner_rule() { return m_owner_css_rule; }
void set_owner_css_rule(CSSRule* rule) { m_owner_css_rule = rule; }
virtual String type() const override { return "text/css"_string; }
CSSRuleList const& rules() const { return *m_rules; }
CSSRuleList& rules() { return *m_rules; }
CSSRuleList* css_rules() { return m_rules; }
CSSRuleList const* css_rules() const { return m_rules; }
WebIDL::ExceptionOr<unsigned> insert_rule(StringView rule, unsigned index);
WebIDL::ExceptionOr<WebIDL::Long> add_rule(Optional<String> selector, Optional<String> style, Optional<WebIDL::UnsignedLong> index);
WebIDL::ExceptionOr<void> remove_rule(Optional<WebIDL::UnsignedLong> index);
WebIDL::ExceptionOr<void> delete_rule(unsigned index);
GC::Ref<WebIDL::Promise> replace(String text);
WebIDL::ExceptionOr<void> replace_sync(StringView text);
void for_each_effective_rule(TraversalOrder, Function<void(CSSRule const&)> const& callback) const;
void for_each_effective_style_producing_rule(Function<void(CSSRule const&)> const& callback) const;
// Returns whether the match state of any media queries changed after evaluation.
bool evaluate_media_queries(DOM::Document const&);
void for_each_effective_keyframes_at_rule(Function<void(CSSKeyframesRule const&)> const& callback) const;
void for_each_effective_counter_style_at_rule(Function<void(CSSCounterStyleRule const&)> const& callback) const;
HashTable<GC::Ptr<DOM::Node>> const& owning_documents_or_shadow_roots() const { return m_owning_documents_or_shadow_roots; }
void add_owning_document_or_shadow_root(DOM::Node& document_or_shadow_root);
void remove_owning_document_or_shadow_root(DOM::Node& document_or_shadow_root);
void invalidate_owners(DOM::StyleInvalidationReason, ShadowRootStylesheetEffects const* previous_sheet_effects = nullptr);
GC::Ptr<DOM::Document> owning_document() const;
virtual void set_disabled(bool) override;
void for_each_owning_style_scope(Function<void(StyleScope&)> const&) const;
NonnullRefPtr<StyleCache> shared_single_constructed_sheet_style_cache(StyleScope&);
Optional<FlyString> default_namespace() const;
GC::Ptr<CSSNamespaceRule> default_namespace_rule() const { return m_default_namespace_rule; }
HashTable<FlyString> declared_namespaces() const;
Optional<FlyString> namespace_uri(StringView namespace_prefix) const;
Vector<GC::Ref<CSSImportRule>> const& import_rules() const { return m_import_rules; }
Optional<::URL::URL> base_url() const { return m_base_url; }
void set_base_url(Optional<::URL::URL> base_url) { m_base_url = move(base_url); }
void register_pending_image_value(ImageStyleValue& value) { m_pending_image_values.append(value); }
void load_pending_image_resources(DOM::Document&);
bool constructed() const { return m_constructed; }
GC::Ptr<DOM::Document const> constructor_document() const { return m_constructor_document; }
void set_constructor_document(GC::Ptr<DOM::Document const> constructor_document) { m_constructor_document = constructor_document; }
bool disallow_modification() const { return m_disallow_modification; }
void set_source_text(String);
Optional<String> source_text(Badge<DOM::Document>) const;
void add_critical_subresource(Subresource&);
void remove_critical_subresource(Subresource&);
LoadingState loading_state() const;
void check_if_loading_completed();
private:
CSSStyleSheet(JS::Realm&, CSSRuleList&, MediaList&, Optional<::URL::URL> location);
virtual void initialize(JS::Realm&) override;
virtual void visit_edges(Cell::Visitor&) override;
void recalculate_rule_caches();
void invalidate_shared_style_cache();
void set_constructed(bool constructed) { m_constructed = constructed; }
void set_disallow_modification(bool disallow_modification) { m_disallow_modification = disallow_modification; }
Parser::ParsingParams make_parsing_params() const;
Optional<String> m_source_text;
GC::Ptr<CSSRuleList> m_rules;
GC::Ptr<CSSNamespaceRule> m_default_namespace_rule;
HashMap<FlyString, GC::Ptr<CSSNamespaceRule>> m_namespace_rules;
Vector<GC::Ref<CSSImportRule>> m_import_rules;
GC::Ptr<CSSRule> m_owner_css_rule;
Optional<::URL::URL> m_base_url;
GC::Ptr<DOM::Document const> m_constructor_document;
HashTable<GC::Ptr<DOM::Node>> m_owning_documents_or_shadow_roots;
bool m_constructed { false };
bool m_disallow_modification { false };
Optional<bool> m_did_match;
RefPtr<StyleCache> m_shared_single_constructed_sheet_style_cache;
Vector<Subresource&> m_critical_subresources;
IGNORE_GC Vector<WeakPtr<ImageStyleValue>> m_pending_image_values;
};
}