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33a9e6d050
<!-- Please describe your changes on the following line: --> Before this PR, every object reflected in CSSOM is in `Arc<RwLock<_>>` to enable safe (synchronized) mutable aliasing. Acquiring all these locks has significant cost during selector matching: * https://bugzilla.mozilla.org/show_bug.cgi?id=1311469 * https://bugzilla.mozilla.org/show_bug.cgi?id=1335941 * https://bugzilla.mozilla.org/show_bug.cgi?id=1339703 This PR introduce a mechanism to protect many objects with the same `RwLock` that only needs to be acquired once. In Stylo, there is one such lock per process (in a `lazy_static`), used for everything. I non-Stylo Servo, I originally intended to have one such lock per document (for author-origin stylesheets, and one per process for user-agent and user sytlesheets since they’re shared across documents, and never mutated anyway). However I failed to have the same document-specific (or pipeline-specific) `Arc` reachable from both `Document` nodes and `LayoutThread`. Recursively following callers lead me to include this `Arc` in `UnprivilegedPipelineContent`, but that needs to be serializable. So there is a second process-wide lock. This was previously #15998, closed accidentally. --- <!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: --> - [x] `./mach build -d` does not report any errors - [x] `./mach test-tidy` does not report any errors - [ ] These changes fix #__ (github issue number if applicable). <!-- Either: --> - [ ] There are tests for these changes OR - [ ] These changes do not require tests because _____ <!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. --> Source-Repo: https://github.com/servo/servo Source-Revision: bb54f0a429de0e8b8861f8071b6cf82f73622664 --HG-- extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear extra : subtree_revision : 851230e57ac8775707df5f0f103be5feac81fc41
1059 lines
38 KiB
Rust
1059 lines
38 KiB
Rust
/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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//! Style sheets and their CSS rules.
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#![deny(missing_docs)]
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use {Atom, Prefix, Namespace};
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use cssparser::{AtRuleParser, Parser, QualifiedRuleParser};
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use cssparser::{AtRuleType, RuleListParser, SourcePosition, Token, parse_one_rule};
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use cssparser::ToCss as ParserToCss;
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use error_reporting::ParseErrorReporter;
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use font_face::{FontFaceRule, parse_font_face_block};
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use keyframes::{Keyframe, parse_keyframe_list};
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use media_queries::{Device, MediaList, parse_media_query_list};
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use parking_lot::RwLock;
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use parser::{ParserContext, ParserContextExtraData, log_css_error};
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use properties::{PropertyDeclarationBlock, parse_property_declaration_list};
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use selector_parser::{SelectorImpl, SelectorParser};
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use selectors::parser::SelectorList;
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use servo_config::prefs::PREFS;
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use servo_url::ServoUrl;
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use shared_lock::{SharedRwLock, Locked, ToCssWithGuard, SharedRwLockReadGuard};
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use std::cell::Cell;
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use std::fmt;
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use std::sync::Arc;
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use std::sync::atomic::{AtomicBool, Ordering};
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use style_traits::ToCss;
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use stylist::FnvHashMap;
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use supports::SupportsCondition;
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use values::specified::url::SpecifiedUrl;
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use viewport::ViewportRule;
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/// Each style rule has an origin, which determines where it enters the cascade.
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///
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/// http://dev.w3.org/csswg/css-cascade/#cascading-origins
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#[derive(Clone, PartialEq, Eq, Copy, Debug)]
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#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
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pub enum Origin {
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/// http://dev.w3.org/csswg/css-cascade/#cascade-origin-ua
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UserAgent,
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/// http://dev.w3.org/csswg/css-cascade/#cascade-origin-author
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Author,
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/// http://dev.w3.org/csswg/css-cascade/#cascade-origin-user
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User,
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}
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/// A set of namespaces applying to a given stylesheet.
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#[derive(Default, Debug)]
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#[allow(missing_docs)]
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pub struct Namespaces {
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pub default: Option<Namespace>,
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pub prefixes: FnvHashMap<Prefix , Namespace>,
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}
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/// A list of CSS rules.
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#[derive(Debug)]
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pub struct CssRules(pub Vec<CssRule>);
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impl CssRules {
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/// Whether this CSS rules is empty.
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pub fn is_empty(&self) -> bool {
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self.0.is_empty()
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}
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}
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#[allow(missing_docs)]
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pub enum RulesMutateError {
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Syntax,
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IndexSize,
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HierarchyRequest,
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InvalidState,
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}
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impl From<SingleRuleParseError> for RulesMutateError {
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fn from(other: SingleRuleParseError) -> Self {
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match other {
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SingleRuleParseError::Syntax => RulesMutateError::Syntax,
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SingleRuleParseError::Hierarchy => RulesMutateError::HierarchyRequest,
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}
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}
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}
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impl CssRules {
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#[allow(missing_docs)]
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pub fn new(rules: Vec<CssRule>, shared_lock: &SharedRwLock) -> Arc<Locked<CssRules>> {
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Arc::new(shared_lock.wrap(CssRules(rules)))
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}
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fn only_ns_or_import(&self) -> bool {
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self.0.iter().all(|r| {
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match *r {
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CssRule::Namespace(..) |
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CssRule::Import(..) => true,
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_ => false
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}
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})
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}
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/// https://drafts.csswg.org/cssom/#insert-a-css-rule
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pub fn insert_rule(&mut self, rule: &str, parent_stylesheet: &Stylesheet, index: usize, nested: bool)
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-> Result<CssRule, RulesMutateError> {
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// Step 1, 2
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if index > self.0.len() {
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return Err(RulesMutateError::IndexSize);
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}
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// Computes the parser state at the given index
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let state = if nested {
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None
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} else if index == 0 {
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Some(State::Start)
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} else {
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self.0.get(index - 1).map(CssRule::rule_state)
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};
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// Step 3, 4
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// XXXManishearth should we also store the namespace map?
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let (new_rule, new_state) =
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try!(CssRule::parse(&rule, parent_stylesheet,
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ParserContextExtraData::default(), state));
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// Step 5
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// Computes the maximum allowed parser state at a given index.
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let rev_state = self.0.get(index).map_or(State::Body, CssRule::rule_state);
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if new_state > rev_state {
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// We inserted a rule too early, e.g. inserting
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// a regular style rule before @namespace rules
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return Err(RulesMutateError::HierarchyRequest);
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}
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// Step 6
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if let CssRule::Namespace(..) = new_rule {
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if !self.only_ns_or_import() {
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return Err(RulesMutateError::InvalidState);
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}
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}
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self.0.insert(index, new_rule.clone());
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Ok(new_rule)
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}
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/// https://drafts.csswg.org/cssom/#remove-a-css-rule
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pub fn remove_rule(&mut self, index: usize) -> Result<(), RulesMutateError> {
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// Step 1, 2
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if index >= self.0.len() {
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return Err(RulesMutateError::IndexSize);
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}
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{
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// Step 3
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let ref rule = self.0[index];
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// Step 4
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if let CssRule::Namespace(..) = *rule {
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if !self.only_ns_or_import() {
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return Err(RulesMutateError::InvalidState);
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}
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}
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}
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// Step 5, 6
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self.0.remove(index);
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Ok(())
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}
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}
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/// The structure servo uses to represent a stylesheet.
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#[derive(Debug)]
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pub struct Stylesheet {
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/// List of rules in the order they were found (important for
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/// cascading order)
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pub rules: Arc<Locked<CssRules>>,
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/// List of media associated with the Stylesheet.
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pub media: Arc<Locked<MediaList>>,
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/// The origin of this stylesheet.
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pub origin: Origin,
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/// The base url this stylesheet should use.
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pub base_url: ServoUrl,
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/// The lock used for objects inside this stylesheet
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pub shared_lock: SharedRwLock,
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/// The namespaces that apply to this stylesheet.
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pub namespaces: RwLock<Namespaces>,
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/// Whether this stylesheet would be dirty when the viewport size changes.
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pub dirty_on_viewport_size_change: AtomicBool,
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/// Whether this stylesheet should be disabled.
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pub disabled: AtomicBool,
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}
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/// This structure holds the user-agent and user stylesheets.
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pub struct UserAgentStylesheets {
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/// The lock used for user-agent stylesheets.
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pub shared_lock: SharedRwLock,
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/// The user or user agent stylesheets.
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pub user_or_user_agent_stylesheets: Vec<Stylesheet>,
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/// The quirks mode stylesheet.
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pub quirks_mode_stylesheet: Stylesheet,
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}
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/// A CSS rule.
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///
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/// TODO(emilio): Lots of spec links should be around.
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#[derive(Debug, Clone)]
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#[allow(missing_docs)]
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pub enum CssRule {
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// No Charset here, CSSCharsetRule has been removed from CSSOM
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// https://drafts.csswg.org/cssom/#changes-from-5-december-2013
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Namespace(Arc<Locked<NamespaceRule>>),
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Import(Arc<Locked<ImportRule>>),
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Style(Arc<Locked<StyleRule>>),
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Media(Arc<Locked<MediaRule>>),
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FontFace(Arc<Locked<FontFaceRule>>),
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Viewport(Arc<Locked<ViewportRule>>),
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Keyframes(Arc<Locked<KeyframesRule>>),
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Supports(Arc<Locked<SupportsRule>>),
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}
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#[allow(missing_docs)]
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pub enum CssRuleType {
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// https://drafts.csswg.org/cssom/#the-cssrule-interface
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Style = 1,
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Charset = 2,
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Import = 3,
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Media = 4,
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FontFace = 5,
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Page = 6,
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// https://drafts.csswg.org/css-animations-1/#interface-cssrule-idl
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Keyframes = 7,
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Keyframe = 8,
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// https://drafts.csswg.org/cssom/#the-cssrule-interface
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Margin = 9,
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Namespace = 10,
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// https://drafts.csswg.org/css-counter-styles-3/#extentions-to-cssrule-interface
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CounterStyle = 11,
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// https://drafts.csswg.org/css-conditional-3/#extentions-to-cssrule-interface
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Supports = 12,
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// https://drafts.csswg.org/css-fonts-3/#om-fontfeaturevalues
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FontFeatureValues = 14,
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// https://drafts.csswg.org/css-device-adapt/#css-rule-interface
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Viewport = 15,
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}
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/// Error reporter which silently forgets errors
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pub struct MemoryHoleReporter;
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impl ParseErrorReporter for MemoryHoleReporter {
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fn report_error(&self,
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_: &mut Parser,
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_: SourcePosition,
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_: &str,
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_: &ServoUrl) {
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// do nothing
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}
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}
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#[allow(missing_docs)]
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pub enum SingleRuleParseError {
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Syntax,
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Hierarchy,
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}
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impl CssRule {
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#[allow(missing_docs)]
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pub fn rule_type(&self) -> CssRuleType {
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match *self {
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CssRule::Style(_) => CssRuleType::Style,
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CssRule::Import(_) => CssRuleType::Import,
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CssRule::Media(_) => CssRuleType::Media,
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CssRule::FontFace(_) => CssRuleType::FontFace,
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CssRule::Keyframes(_) => CssRuleType::Keyframes,
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CssRule::Namespace(_) => CssRuleType::Namespace,
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CssRule::Viewport(_) => CssRuleType::Viewport,
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CssRule::Supports(_) => CssRuleType::Supports,
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}
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}
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fn rule_state(&self) -> State {
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match *self {
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// CssRule::Charset(..) => State::Start,
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CssRule::Import(..) => State::Imports,
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CssRule::Namespace(..) => State::Namespaces,
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_ => State::Body,
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}
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}
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/// Call `f` with the slice of rules directly contained inside this rule.
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///
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/// Note that only some types of rules can contain rules. An empty slice is
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/// used for others.
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///
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/// This will not recurse down unsupported @supports rules
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pub fn with_nested_rules_and_mq<F, R>(&self, guard: &SharedRwLockReadGuard, mut f: F) -> R
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where F: FnMut(&[CssRule], Option<&MediaList>) -> R {
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match *self {
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CssRule::Import(ref lock) => {
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let rule = lock.read_with(guard);
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let media = rule.stylesheet.media.read_with(guard);
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let rules = rule.stylesheet.rules.read_with(guard);
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// FIXME(emilio): Include the nested rules if the stylesheet is
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// loaded.
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f(&rules.0, Some(&media))
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}
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CssRule::Namespace(_) |
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CssRule::Style(_) |
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CssRule::FontFace(_) |
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CssRule::Viewport(_) |
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CssRule::Keyframes(_) => {
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f(&[], None)
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}
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CssRule::Media(ref lock) => {
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let media_rule = lock.read_with(guard);
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let mq = media_rule.media_queries.read_with(guard);
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let rules = &media_rule.rules.read_with(guard).0;
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f(rules, Some(&mq))
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}
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CssRule::Supports(ref lock) => {
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let supports_rule = lock.read_with(guard);
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let enabled = supports_rule.enabled;
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if enabled {
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let rules = &supports_rule.rules.read_with(guard).0;
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f(rules, None)
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} else {
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f(&[], None)
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}
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}
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}
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}
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// input state is None for a nested rule
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// Returns a parsed CSS rule and the final state of the parser
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#[allow(missing_docs)]
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pub fn parse(css: &str,
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parent_stylesheet: &Stylesheet,
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extra_data: ParserContextExtraData,
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state: Option<State>)
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-> Result<(Self, State), SingleRuleParseError> {
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let error_reporter = MemoryHoleReporter;
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let mut namespaces = parent_stylesheet.namespaces.write();
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let context = ParserContext::new_with_extra_data(parent_stylesheet.origin,
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&parent_stylesheet.base_url,
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&error_reporter,
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extra_data);
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let mut input = Parser::new(css);
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// nested rules are in the body state
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let state = state.unwrap_or(State::Body);
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let mut rule_parser = TopLevelRuleParser {
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stylesheet_origin: parent_stylesheet.origin,
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context: context,
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shared_lock: &parent_stylesheet.shared_lock,
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loader: None,
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state: Cell::new(state),
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namespaces: &mut namespaces,
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};
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match parse_one_rule(&mut input, &mut rule_parser) {
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Ok(result) => Ok((result, rule_parser.state.get())),
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Err(_) => {
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if let State::Invalid = rule_parser.state.get() {
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Err(SingleRuleParseError::Hierarchy)
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||
} else {
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Err(SingleRuleParseError::Syntax)
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}
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}
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}
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}
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}
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impl ToCssWithGuard for CssRule {
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// https://drafts.csswg.org/cssom/#serialize-a-css-rule
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fn to_css<W>(&self, guard: &SharedRwLockReadGuard, dest: &mut W) -> fmt::Result
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where W: fmt::Write {
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match *self {
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CssRule::Namespace(ref lock) => lock.read_with(guard).to_css(guard, dest),
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CssRule::Import(ref lock) => lock.read_with(guard).to_css(guard, dest),
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CssRule::Style(ref lock) => lock.read_with(guard).to_css(guard, dest),
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CssRule::FontFace(ref lock) => lock.read_with(guard).to_css(guard, dest),
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CssRule::Viewport(ref lock) => lock.read_with(guard).to_css(guard, dest),
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CssRule::Keyframes(ref lock) => lock.read_with(guard).to_css(guard, dest),
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CssRule::Media(ref lock) => lock.read_with(guard).to_css(guard, dest),
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CssRule::Supports(ref lock) => lock.read_with(guard).to_css(guard, dest),
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}
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}
|
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}
|
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|
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#[derive(Debug, PartialEq)]
|
||
#[allow(missing_docs)]
|
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pub struct NamespaceRule {
|
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/// `None` for the default Namespace
|
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pub prefix: Option<Prefix>,
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pub url: Namespace,
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}
|
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|
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impl ToCssWithGuard for NamespaceRule {
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// https://drafts.csswg.org/cssom/#serialize-a-css-rule CSSNamespaceRule
|
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fn to_css<W>(&self, _guard: &SharedRwLockReadGuard, dest: &mut W) -> fmt::Result
|
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where W: fmt::Write {
|
||
try!(dest.write_str("@namespace "));
|
||
if let Some(ref prefix) = self.prefix {
|
||
try!(dest.write_str(&*prefix.to_string()));
|
||
try!(dest.write_str(" "));
|
||
}
|
||
try!(dest.write_str("url(\""));
|
||
try!(dest.write_str(&*self.url.to_string()));
|
||
dest.write_str("\");")
|
||
}
|
||
}
|
||
|
||
|
||
/// The [`@import`][import] at-rule.
|
||
///
|
||
/// [import]: https://drafts.csswg.org/css-cascade-3/#at-import
|
||
#[derive(Debug)]
|
||
pub struct ImportRule {
|
||
/// The `<url>` this `@import` rule is loading.
|
||
pub url: SpecifiedUrl,
|
||
|
||
/// The stylesheet is always present.
|
||
///
|
||
/// It contains an empty list of rules and namespace set that is updated
|
||
/// when it loads.
|
||
pub stylesheet: Arc<Stylesheet>,
|
||
}
|
||
|
||
impl ToCssWithGuard for ImportRule {
|
||
fn to_css<W>(&self, guard: &SharedRwLockReadGuard, dest: &mut W) -> fmt::Result
|
||
where W: fmt::Write {
|
||
try!(dest.write_str("@import "));
|
||
try!(self.url.to_css(dest));
|
||
let media = self.stylesheet.media.read_with(guard);
|
||
if !media.is_empty() {
|
||
try!(dest.write_str(" "));
|
||
try!(media.to_css(dest));
|
||
}
|
||
dest.write_str(";")
|
||
}
|
||
}
|
||
|
||
/// A [`@keyframes`][keyframes] rule.
|
||
///
|
||
/// [keyframes]: https://drafts.csswg.org/css-animations/#keyframes
|
||
#[derive(Debug)]
|
||
pub struct KeyframesRule {
|
||
/// The name of the current animation.
|
||
pub name: Atom,
|
||
/// The keyframes specified for this CSS rule.
|
||
pub keyframes: Vec<Arc<Locked<Keyframe>>>,
|
||
}
|
||
|
||
impl ToCssWithGuard for KeyframesRule {
|
||
// Serialization of KeyframesRule is not specced.
|
||
fn to_css<W>(&self, guard: &SharedRwLockReadGuard, dest: &mut W) -> fmt::Result
|
||
where W: fmt::Write {
|
||
try!(dest.write_str("@keyframes "));
|
||
try!(dest.write_str(&*self.name.to_string()));
|
||
try!(dest.write_str(" { "));
|
||
let iter = self.keyframes.iter();
|
||
let mut first = true;
|
||
for lock in iter {
|
||
if !first {
|
||
try!(dest.write_str(" "));
|
||
}
|
||
first = false;
|
||
let keyframe = lock.read_with(&guard);
|
||
try!(keyframe.to_css(guard, dest));
|
||
}
|
||
dest.write_str(" }")
|
||
}
|
||
}
|
||
|
||
#[allow(missing_docs)]
|
||
#[derive(Debug)]
|
||
pub struct MediaRule {
|
||
pub media_queries: Arc<Locked<MediaList>>,
|
||
pub rules: Arc<Locked<CssRules>>,
|
||
}
|
||
|
||
impl ToCssWithGuard for MediaRule {
|
||
// Serialization of MediaRule is not specced.
|
||
// https://drafts.csswg.org/cssom/#serialize-a-css-rule CSSMediaRule
|
||
fn to_css<W>(&self, guard: &SharedRwLockReadGuard, dest: &mut W) -> fmt::Result
|
||
where W: fmt::Write {
|
||
try!(dest.write_str("@media "));
|
||
try!(self.media_queries.read_with(guard).to_css(dest));
|
||
try!(dest.write_str(" {"));
|
||
for rule in self.rules.read_with(guard).0.iter() {
|
||
try!(dest.write_str(" "));
|
||
try!(rule.to_css(guard, dest));
|
||
}
|
||
dest.write_str(" }")
|
||
}
|
||
}
|
||
|
||
|
||
#[derive(Debug)]
|
||
/// An @supports rule
|
||
pub struct SupportsRule {
|
||
/// The parsed condition
|
||
pub condition: SupportsCondition,
|
||
/// Child rules
|
||
pub rules: Arc<Locked<CssRules>>,
|
||
/// The result of evaluating the condition
|
||
pub enabled: bool,
|
||
}
|
||
|
||
impl ToCssWithGuard for SupportsRule {
|
||
fn to_css<W>(&self, guard: &SharedRwLockReadGuard, dest: &mut W) -> fmt::Result
|
||
where W: fmt::Write {
|
||
try!(dest.write_str("@supports "));
|
||
try!(self.condition.to_css(dest));
|
||
try!(dest.write_str(" {"));
|
||
for rule in self.rules.read_with(guard).0.iter() {
|
||
try!(dest.write_str(" "));
|
||
try!(rule.to_css(guard, dest));
|
||
}
|
||
dest.write_str(" }")
|
||
}
|
||
}
|
||
|
||
#[allow(missing_docs)]
|
||
#[derive(Debug)]
|
||
pub struct StyleRule {
|
||
pub selectors: SelectorList<SelectorImpl>,
|
||
pub block: Arc<Locked<PropertyDeclarationBlock>>,
|
||
}
|
||
|
||
impl ToCssWithGuard for StyleRule {
|
||
// https://drafts.csswg.org/cssom/#serialize-a-css-rule CSSStyleRule
|
||
fn to_css<W>(&self, guard: &SharedRwLockReadGuard, dest: &mut W) -> fmt::Result
|
||
where W: fmt::Write {
|
||
// Step 1
|
||
try!(self.selectors.to_css(dest));
|
||
// Step 2
|
||
try!(dest.write_str(" { "));
|
||
// Step 3
|
||
let declaration_block = self.block.read_with(guard);
|
||
try!(declaration_block.to_css(dest));
|
||
// Step 4
|
||
if declaration_block.declarations().len() > 0 {
|
||
try!(write!(dest, " "));
|
||
}
|
||
// Step 5
|
||
try!(dest.write_str("}"));
|
||
Ok(())
|
||
}
|
||
}
|
||
|
||
impl Stylesheet {
|
||
/// Updates an empty stylesheet from a given string of text.
|
||
pub fn update_from_str(existing: &Stylesheet,
|
||
css: &str,
|
||
stylesheet_loader: Option<&StylesheetLoader>,
|
||
error_reporter: &ParseErrorReporter,
|
||
extra_data: ParserContextExtraData) {
|
||
let mut namespaces = Namespaces::default();
|
||
let (rules, dirty_on_viewport_size_change) = Stylesheet::parse_rules(
|
||
css, &existing.base_url, existing.origin, &mut namespaces, &existing.shared_lock,
|
||
stylesheet_loader, error_reporter, extra_data,
|
||
);
|
||
|
||
*existing.namespaces.write() = namespaces;
|
||
existing.dirty_on_viewport_size_change
|
||
.store(dirty_on_viewport_size_change, Ordering::Release);
|
||
|
||
// Acquire the lock *after* parsing, to minimize the exclusive section.
|
||
let mut guard = existing.shared_lock.write();
|
||
*existing.rules.write_with(&mut guard) = CssRules(rules);
|
||
}
|
||
|
||
fn parse_rules(css: &str,
|
||
base_url: &ServoUrl,
|
||
origin: Origin,
|
||
namespaces: &mut Namespaces,
|
||
shared_lock: &SharedRwLock,
|
||
stylesheet_loader: Option<&StylesheetLoader>,
|
||
error_reporter: &ParseErrorReporter,
|
||
extra_data: ParserContextExtraData)
|
||
-> (Vec<CssRule>, bool) {
|
||
let mut rules = Vec::new();
|
||
let mut input = Parser::new(css);
|
||
let rule_parser = TopLevelRuleParser {
|
||
stylesheet_origin: origin,
|
||
namespaces: namespaces,
|
||
shared_lock: shared_lock,
|
||
loader: stylesheet_loader,
|
||
context: ParserContext::new_with_extra_data(origin,
|
||
base_url,
|
||
error_reporter,
|
||
extra_data),
|
||
state: Cell::new(State::Start),
|
||
};
|
||
|
||
input.look_for_viewport_percentages();
|
||
|
||
{
|
||
let mut iter = RuleListParser::new_for_stylesheet(&mut input, rule_parser);
|
||
while let Some(result) = iter.next() {
|
||
match result {
|
||
Ok(rule) => rules.push(rule),
|
||
Err(range) => {
|
||
let pos = range.start;
|
||
let message = format!("Invalid rule: '{}'", iter.input.slice(range));
|
||
log_css_error(iter.input, pos, &*message, &iter.parser.context);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
(rules, input.seen_viewport_percentages())
|
||
}
|
||
|
||
/// Creates an empty stylesheet and parses it with a given base url, origin
|
||
/// and media.
|
||
///
|
||
/// Effectively creates a new stylesheet and forwards the hard work to
|
||
/// `Stylesheet::update_from_str`.
|
||
pub fn from_str(css: &str,
|
||
base_url: ServoUrl,
|
||
origin: Origin,
|
||
media: MediaList,
|
||
shared_lock: SharedRwLock,
|
||
stylesheet_loader: Option<&StylesheetLoader>,
|
||
error_reporter: &ParseErrorReporter,
|
||
extra_data: ParserContextExtraData) -> Stylesheet {
|
||
let mut namespaces = Namespaces::default();
|
||
let (rules, dirty_on_viewport_size_change) = Stylesheet::parse_rules(
|
||
css, &base_url, origin, &mut namespaces, &shared_lock,
|
||
stylesheet_loader, error_reporter, extra_data,
|
||
);
|
||
Stylesheet {
|
||
origin: origin,
|
||
base_url: base_url,
|
||
namespaces: RwLock::new(namespaces),
|
||
rules: CssRules::new(rules, &shared_lock),
|
||
media: Arc::new(shared_lock.wrap(media)),
|
||
shared_lock: shared_lock,
|
||
dirty_on_viewport_size_change: AtomicBool::new(dirty_on_viewport_size_change),
|
||
disabled: AtomicBool::new(false),
|
||
}
|
||
}
|
||
|
||
/// Whether this stylesheet can be dirty on viewport size change.
|
||
pub fn dirty_on_viewport_size_change(&self) -> bool {
|
||
self.dirty_on_viewport_size_change.load(Ordering::SeqCst)
|
||
}
|
||
|
||
/// When CSSOM inserts a rule or declaration into this stylesheet, it needs to call this method
|
||
/// with the return value of `cssparser::Parser::seen_viewport_percentages`.
|
||
///
|
||
/// FIXME: actually make these calls
|
||
///
|
||
/// Note: when *removing* a rule or declaration that contains a viewport percentage,
|
||
/// to keep the flag accurate we’d need to iterator through the rest of the stylesheet to
|
||
/// check for *other* such values.
|
||
///
|
||
/// Instead, we conservatively assume there might be some.
|
||
/// Restyling will some some more work than necessary, but give correct results.
|
||
pub fn inserted_has_viewport_percentages(&self, has_viewport_percentages: bool) {
|
||
self.dirty_on_viewport_size_change.fetch_or(has_viewport_percentages, Ordering::SeqCst);
|
||
}
|
||
|
||
/// Returns whether the style-sheet applies for the current device depending
|
||
/// on the associated MediaList.
|
||
///
|
||
/// Always true if no associated MediaList exists.
|
||
pub fn is_effective_for_device(&self, device: &Device, guard: &SharedRwLockReadGuard) -> bool {
|
||
self.media.read_with(guard).evaluate(device)
|
||
}
|
||
|
||
/// Return an iterator over the effective rules within the style-sheet, as
|
||
/// according to the supplied `Device`.
|
||
///
|
||
/// If a condition does not hold, its associated conditional group rule and
|
||
/// nested rules will be skipped. Use `rules` if all rules need to be
|
||
/// examined.
|
||
#[inline]
|
||
pub fn effective_rules<F>(&self, device: &Device, guard: &SharedRwLockReadGuard, mut f: F)
|
||
where F: FnMut(&CssRule) {
|
||
effective_rules(&self.rules.read_with(guard).0, device, guard, &mut f);
|
||
}
|
||
|
||
/// Returns whether the stylesheet has been explicitly disabled through the
|
||
/// CSSOM.
|
||
pub fn disabled(&self) -> bool {
|
||
self.disabled.load(Ordering::SeqCst)
|
||
}
|
||
|
||
/// Records that the stylesheet has been explicitly disabled through the
|
||
/// CSSOM.
|
||
///
|
||
/// Returns whether the the call resulted in a change in disabled state.
|
||
///
|
||
/// Disabled stylesheets remain in the document, but their rules are not
|
||
/// added to the Stylist.
|
||
pub fn set_disabled(&self, disabled: bool) -> bool {
|
||
self.disabled.swap(disabled, Ordering::SeqCst) != disabled
|
||
}
|
||
}
|
||
|
||
fn effective_rules<F>(rules: &[CssRule], device: &Device, guard: &SharedRwLockReadGuard, f: &mut F)
|
||
where F: FnMut(&CssRule) {
|
||
for rule in rules {
|
||
f(rule);
|
||
rule.with_nested_rules_and_mq(guard, |rules, mq| {
|
||
if let Some(media_queries) = mq {
|
||
if !media_queries.evaluate(device) {
|
||
return
|
||
}
|
||
}
|
||
effective_rules(rules, device, guard, f)
|
||
})
|
||
}
|
||
}
|
||
|
||
macro_rules! rule_filter {
|
||
($( $method: ident($variant:ident => $rule_type: ident), )+) => {
|
||
impl Stylesheet {
|
||
$(
|
||
#[allow(missing_docs)]
|
||
pub fn $method<F>(&self, device: &Device, guard: &SharedRwLockReadGuard, mut f: F)
|
||
where F: FnMut(&$rule_type) {
|
||
self.effective_rules(device, guard, |rule| {
|
||
if let CssRule::$variant(ref lock) = *rule {
|
||
let rule = lock.read_with(guard);
|
||
f(&rule)
|
||
}
|
||
})
|
||
}
|
||
)+
|
||
}
|
||
}
|
||
}
|
||
|
||
rule_filter! {
|
||
effective_style_rules(Style => StyleRule),
|
||
effective_media_rules(Media => MediaRule),
|
||
effective_font_face_rules(FontFace => FontFaceRule),
|
||
effective_viewport_rules(Viewport => ViewportRule),
|
||
effective_keyframes_rules(Keyframes => KeyframesRule),
|
||
effective_supports_rules(Supports => SupportsRule),
|
||
}
|
||
|
||
/// The stylesheet loader is the abstraction used to trigger network requests
|
||
/// for `@import` rules.
|
||
pub trait StylesheetLoader {
|
||
/// Request a stylesheet after parsing a given `@import` rule.
|
||
///
|
||
/// The called code is responsible to update the `stylesheet` rules field
|
||
/// when the sheet is done loading.
|
||
///
|
||
/// The convoluted signature allows impls to look at MediaList and ImportRule
|
||
/// before they’re locked, while keeping the trait object-safe.
|
||
fn request_stylesheet(
|
||
&self,
|
||
media: MediaList,
|
||
make_import: &mut FnMut(MediaList) -> ImportRule,
|
||
make_arc: &mut FnMut(ImportRule) -> Arc<Locked<ImportRule>>,
|
||
) -> Arc<Locked<ImportRule>>;
|
||
}
|
||
|
||
struct NoOpLoader;
|
||
|
||
impl StylesheetLoader for NoOpLoader {
|
||
fn request_stylesheet(
|
||
&self,
|
||
media: MediaList,
|
||
make_import: &mut FnMut(MediaList) -> ImportRule,
|
||
make_arc: &mut FnMut(ImportRule) -> Arc<Locked<ImportRule>>,
|
||
) -> Arc<Locked<ImportRule>> {
|
||
make_arc(make_import(media))
|
||
}
|
||
}
|
||
|
||
|
||
struct TopLevelRuleParser<'a> {
|
||
stylesheet_origin: Origin,
|
||
namespaces: &'a mut Namespaces,
|
||
shared_lock: &'a SharedRwLock,
|
||
loader: Option<&'a StylesheetLoader>,
|
||
context: ParserContext<'a>,
|
||
state: Cell<State>,
|
||
}
|
||
|
||
impl<'b> TopLevelRuleParser<'b> {
|
||
fn nested<'a: 'b>(&'a self) -> NestedRuleParser<'a, 'b> {
|
||
NestedRuleParser {
|
||
stylesheet_origin: self.stylesheet_origin,
|
||
shared_lock: self.shared_lock,
|
||
context: &self.context,
|
||
namespaces: self.namespaces,
|
||
}
|
||
}
|
||
}
|
||
|
||
#[derive(Eq, PartialEq, Ord, PartialOrd, Copy, Clone)]
|
||
#[allow(missing_docs)]
|
||
pub enum State {
|
||
Start = 1,
|
||
Imports = 2,
|
||
Namespaces = 3,
|
||
Body = 4,
|
||
Invalid = 5,
|
||
}
|
||
|
||
|
||
enum AtRulePrelude {
|
||
/// A @font-face rule prelude.
|
||
FontFace,
|
||
/// A @media rule prelude, with its media queries.
|
||
Media(Arc<Locked<MediaList>>),
|
||
/// An @supports rule, with its conditional
|
||
Supports(SupportsCondition),
|
||
/// A @viewport rule prelude.
|
||
Viewport,
|
||
/// A @keyframes rule, with its animation name.
|
||
Keyframes(Atom),
|
||
}
|
||
|
||
|
||
impl<'a> AtRuleParser for TopLevelRuleParser<'a> {
|
||
type Prelude = AtRulePrelude;
|
||
type AtRule = CssRule;
|
||
|
||
fn parse_prelude(&mut self, name: &str, input: &mut Parser)
|
||
-> Result<AtRuleType<AtRulePrelude, CssRule>, ()> {
|
||
match_ignore_ascii_case! { name,
|
||
"import" => {
|
||
if self.state.get() <= State::Imports {
|
||
self.state.set(State::Imports);
|
||
let url_string = input.expect_url_or_string()?;
|
||
let specified_url = SpecifiedUrl::parse_from_string(url_string, &self.context)?;
|
||
|
||
let media = parse_media_query_list(input);
|
||
|
||
let noop_loader = NoOpLoader;
|
||
let is_valid_url = specified_url.url().is_some();
|
||
let loader = if is_valid_url {
|
||
self.loader.expect("Expected a stylesheet loader for @import")
|
||
} else {
|
||
&noop_loader
|
||
};
|
||
|
||
let mut specified_url = Some(specified_url);
|
||
let arc = loader.request_stylesheet(media, &mut |media| {
|
||
ImportRule {
|
||
url: specified_url.take().unwrap(),
|
||
stylesheet: Arc::new(Stylesheet {
|
||
rules: CssRules::new(Vec::new(), self.shared_lock),
|
||
media: Arc::new(self.shared_lock.wrap(media)),
|
||
shared_lock: self.shared_lock.clone(),
|
||
origin: self.context.stylesheet_origin,
|
||
base_url: self.context.base_url.clone(),
|
||
namespaces: RwLock::new(Namespaces::default()),
|
||
dirty_on_viewport_size_change: AtomicBool::new(false),
|
||
disabled: AtomicBool::new(false),
|
||
})
|
||
}
|
||
}, &mut |import_rule| {
|
||
Arc::new(self.shared_lock.wrap(import_rule))
|
||
});
|
||
return Ok(AtRuleType::WithoutBlock(CssRule::Import(arc)))
|
||
} else {
|
||
self.state.set(State::Invalid);
|
||
return Err(()) // "@import must be before any rule but @charset"
|
||
}
|
||
},
|
||
"namespace" => {
|
||
if self.state.get() <= State::Namespaces {
|
||
self.state.set(State::Namespaces);
|
||
|
||
let prefix_result = input.try(|input| input.expect_ident());
|
||
let url = Namespace::from(try!(input.expect_url_or_string()));
|
||
|
||
let opt_prefix = if let Ok(prefix) = prefix_result {
|
||
let prefix = Prefix::from(prefix);
|
||
self.namespaces.prefixes.insert(prefix.clone(), url.clone());
|
||
Some(prefix)
|
||
} else {
|
||
self.namespaces.default = Some(url.clone());
|
||
None
|
||
};
|
||
|
||
return Ok(AtRuleType::WithoutBlock(CssRule::Namespace(Arc::new(
|
||
self.shared_lock.wrap(NamespaceRule {
|
||
prefix: opt_prefix,
|
||
url: url,
|
||
})
|
||
))))
|
||
} else {
|
||
self.state.set(State::Invalid);
|
||
return Err(()) // "@namespace must be before any rule but @charset and @import"
|
||
}
|
||
},
|
||
// @charset is removed by rust-cssparser if it’s the first rule in the stylesheet
|
||
// anything left is invalid.
|
||
"charset" => return Err(()), // (insert appropriate error message)
|
||
_ => {}
|
||
}
|
||
// Don't allow starting with an invalid state
|
||
if self.state.get() > State::Body {
|
||
self.state.set(State::Invalid);
|
||
return Err(());
|
||
}
|
||
self.state.set(State::Body);
|
||
AtRuleParser::parse_prelude(&mut self.nested(), name, input)
|
||
}
|
||
|
||
#[inline]
|
||
fn parse_block(&mut self, prelude: AtRulePrelude, input: &mut Parser) -> Result<CssRule, ()> {
|
||
AtRuleParser::parse_block(&mut self.nested(), prelude, input)
|
||
}
|
||
}
|
||
|
||
|
||
impl<'a> QualifiedRuleParser for TopLevelRuleParser<'a> {
|
||
type Prelude = SelectorList<SelectorImpl>;
|
||
type QualifiedRule = CssRule;
|
||
|
||
#[inline]
|
||
fn parse_prelude(&mut self, input: &mut Parser) -> Result<SelectorList<SelectorImpl>, ()> {
|
||
self.state.set(State::Body);
|
||
QualifiedRuleParser::parse_prelude(&mut self.nested(), input)
|
||
}
|
||
|
||
#[inline]
|
||
fn parse_block(&mut self, prelude: SelectorList<SelectorImpl>, input: &mut Parser)
|
||
-> Result<CssRule, ()> {
|
||
QualifiedRuleParser::parse_block(&mut self.nested(), prelude, input)
|
||
}
|
||
}
|
||
|
||
#[derive(Clone)] // shallow, relatively cheap .clone
|
||
struct NestedRuleParser<'a, 'b: 'a> {
|
||
stylesheet_origin: Origin,
|
||
shared_lock: &'a SharedRwLock,
|
||
context: &'a ParserContext<'b>,
|
||
namespaces: &'b Namespaces,
|
||
}
|
||
|
||
impl<'a, 'b> NestedRuleParser<'a, 'b> {
|
||
fn parse_nested_rules(&self, input: &mut Parser) -> Arc<Locked<CssRules>> {
|
||
let mut iter = RuleListParser::new_for_nested_rule(input, self.clone());
|
||
let mut rules = Vec::new();
|
||
while let Some(result) = iter.next() {
|
||
match result {
|
||
Ok(rule) => rules.push(rule),
|
||
Err(range) => {
|
||
let pos = range.start;
|
||
let message = format!("Unsupported rule: '{}'", iter.input.slice(range));
|
||
log_css_error(iter.input, pos, &*message, self.context);
|
||
}
|
||
}
|
||
}
|
||
CssRules::new(rules, self.shared_lock)
|
||
}
|
||
}
|
||
|
||
impl<'a, 'b> AtRuleParser for NestedRuleParser<'a, 'b> {
|
||
type Prelude = AtRulePrelude;
|
||
type AtRule = CssRule;
|
||
|
||
fn parse_prelude(&mut self, name: &str, input: &mut Parser)
|
||
-> Result<AtRuleType<AtRulePrelude, CssRule>, ()> {
|
||
match_ignore_ascii_case! { name,
|
||
"media" => {
|
||
let media_queries = parse_media_query_list(input);
|
||
let arc = Arc::new(self.shared_lock.wrap(media_queries));
|
||
Ok(AtRuleType::WithBlock(AtRulePrelude::Media(arc)))
|
||
},
|
||
"supports" => {
|
||
let cond = SupportsCondition::parse(input)?;
|
||
Ok(AtRuleType::WithBlock(AtRulePrelude::Supports(cond)))
|
||
},
|
||
"font-face" => {
|
||
Ok(AtRuleType::WithBlock(AtRulePrelude::FontFace))
|
||
},
|
||
"viewport" => {
|
||
if PREFS.get("layout.viewport.enabled").as_boolean().unwrap_or(false) ||
|
||
cfg!(feature = "gecko") {
|
||
Ok(AtRuleType::WithBlock(AtRulePrelude::Viewport))
|
||
} else {
|
||
Err(())
|
||
}
|
||
},
|
||
"keyframes" => {
|
||
let name = match input.next() {
|
||
Ok(Token::Ident(ref value)) if value != "none" => Atom::from(&**value),
|
||
Ok(Token::QuotedString(value)) => Atom::from(&*value),
|
||
_ => return Err(())
|
||
};
|
||
|
||
Ok(AtRuleType::WithBlock(AtRulePrelude::Keyframes(Atom::from(name))))
|
||
},
|
||
_ => Err(())
|
||
}
|
||
}
|
||
|
||
fn parse_block(&mut self, prelude: AtRulePrelude, input: &mut Parser) -> Result<CssRule, ()> {
|
||
match prelude {
|
||
AtRulePrelude::FontFace => {
|
||
Ok(CssRule::FontFace(Arc::new(self.shared_lock.wrap(
|
||
try!(parse_font_face_block(self.context, input))))))
|
||
}
|
||
AtRulePrelude::Media(media_queries) => {
|
||
Ok(CssRule::Media(Arc::new(self.shared_lock.wrap(MediaRule {
|
||
media_queries: media_queries,
|
||
rules: self.parse_nested_rules(input),
|
||
}))))
|
||
}
|
||
AtRulePrelude::Supports(cond) => {
|
||
let enabled = cond.eval(self.context);
|
||
Ok(CssRule::Supports(Arc::new(self.shared_lock.wrap(SupportsRule {
|
||
condition: cond,
|
||
rules: self.parse_nested_rules(input),
|
||
enabled: enabled,
|
||
}))))
|
||
}
|
||
AtRulePrelude::Viewport => {
|
||
Ok(CssRule::Viewport(Arc::new(self.shared_lock.wrap(
|
||
try!(ViewportRule::parse(input, self.context))))))
|
||
}
|
||
AtRulePrelude::Keyframes(name) => {
|
||
Ok(CssRule::Keyframes(Arc::new(self.shared_lock.wrap(KeyframesRule {
|
||
name: name,
|
||
keyframes: parse_keyframe_list(&self.context, input, self.shared_lock),
|
||
}))))
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
impl<'a, 'b> QualifiedRuleParser for NestedRuleParser<'a, 'b> {
|
||
type Prelude = SelectorList<SelectorImpl>;
|
||
type QualifiedRule = CssRule;
|
||
|
||
fn parse_prelude(&mut self, input: &mut Parser) -> Result<SelectorList<SelectorImpl>, ()> {
|
||
let selector_parser = SelectorParser {
|
||
stylesheet_origin: self.stylesheet_origin,
|
||
namespaces: self.namespaces,
|
||
};
|
||
SelectorList::parse(&selector_parser, input)
|
||
}
|
||
|
||
fn parse_block(&mut self, prelude: SelectorList<SelectorImpl>, input: &mut Parser)
|
||
-> Result<CssRule, ()> {
|
||
let declarations = parse_property_declaration_list(self.context, input);
|
||
Ok(CssRule::Style(Arc::new(self.shared_lock.wrap(StyleRule {
|
||
selectors: prelude,
|
||
block: Arc::new(self.shared_lock.wrap(declarations))
|
||
}))))
|
||
}
|
||
}
|