script/dom/worklet/
workletglobalscope.rs

1/* This Source Code Form is subject to the terms of the Mozilla Public
2 * License, v. 2.0. If a copy of the MPL was not distributed with this
3 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
4
5use std::borrow::Cow;
6use std::sync::Arc;
7
8use crossbeam_channel::Sender;
9use devtools_traits::ScriptToDevtoolsControlMsg;
10use dom_struct::dom_struct;
11use embedder_traits::{JavaScriptEvaluationError, ScriptToEmbedderChan};
12use js::context::JSContext;
13use net_traits::ResourceThreads;
14use net_traits::image_cache::ImageCache;
15use profile_traits::{mem, time};
16use script_traits::Painter;
17use servo_base::generic_channel::GenericCallback;
18use servo_base::id::PipelineId;
19use servo_constellation_traits::ScriptToConstellationSender;
20use servo_url::{ImmutableOrigin, MutableOrigin, ServoUrl};
21use storage_traits::StorageThreads;
22use stylo_atoms::Atom;
23
24use crate::dom::bindings::inheritance::Castable;
25use crate::dom::bindings::root::DomRoot;
26use crate::dom::bindings::trace::CustomTraceable;
27use crate::dom::bindings::utils::define_all_exposed_interfaces;
28use crate::dom::globalscope::GlobalScope;
29use crate::dom::paintworkletglobalscope::{PaintWorkletGlobalScope, PaintWorkletTask};
30#[cfg(feature = "testbinding")]
31use crate::dom::testworkletglobalscope::{TestWorkletGlobalScope, TestWorkletTask};
32#[cfg(feature = "webgpu")]
33use crate::dom::webgpu::identityhub::IdentityHub;
34use crate::dom::worklet::WorkletExecutor;
35use crate::messaging::MainThreadScriptMsg;
36use crate::realms::enter_auto_realm;
37use crate::script_runtime::IntroductionType;
38
39#[dom_struct]
40/// <https://drafts.css-houdini.org/worklets/#workletglobalscope>
41pub(crate) struct WorkletGlobalScope {
42    /// The global for this worklet.
43    globalscope: GlobalScope,
44    /// The base URL for this worklet.
45    #[no_trace]
46    base_url: ServoUrl,
47    /// Sender back to the script thread
48    to_script_thread_sender: Sender<MainThreadScriptMsg>,
49    /// Worklet task executor
50    executor: WorkletExecutor,
51
52    #[no_trace]
53    /// The pipeline that created this worklet.
54    pipeline_id: PipelineId,
55}
56
57impl WorkletGlobalScope {
58    /// Create a new heap-allocated `WorkletGlobalScope`.
59    pub(crate) fn new(
60        scope_type: WorkletGlobalScopeType,
61        pipeline_id: PipelineId,
62        base_url: ServoUrl,
63        inherited_secure_context: Option<bool>,
64        executor: WorkletExecutor,
65        init: &WorkletGlobalScopeInit,
66        cx: &mut JSContext,
67    ) -> DomRoot<WorkletGlobalScope> {
68        let scope: DomRoot<WorkletGlobalScope> = match scope_type {
69            #[cfg(feature = "testbinding")]
70            WorkletGlobalScopeType::Test => DomRoot::upcast(TestWorkletGlobalScope::new(
71                pipeline_id,
72                base_url,
73                inherited_secure_context,
74                executor,
75                init,
76                cx,
77            )),
78            WorkletGlobalScopeType::Paint => DomRoot::upcast(PaintWorkletGlobalScope::new(
79                pipeline_id,
80                base_url,
81                inherited_secure_context,
82                executor,
83                init,
84                cx,
85            )),
86        };
87
88        let mut realm = enter_auto_realm(cx, &*scope);
89        let mut realm = realm.current_realm();
90        define_all_exposed_interfaces(&mut realm, scope.upcast());
91
92        scope
93    }
94
95    /// Create a new stack-allocated `WorkletGlobalScope`.
96    pub(crate) fn new_inherited(
97        pipeline_id: PipelineId,
98        base_url: ServoUrl,
99        inherited_secure_context: Option<bool>,
100        executor: WorkletExecutor,
101        init: &WorkletGlobalScopeInit,
102    ) -> Self {
103        Self {
104            globalscope: GlobalScope::new_inherited(
105                init.devtools_chan.clone(),
106                init.mem_profiler_chan.clone(),
107                init.time_profiler_chan.clone(),
108                init.script_to_constellation_sender.clone(),
109                init.to_embedder_sender.clone(),
110                init.resource_threads.clone(),
111                init.storage_threads.clone(),
112                MutableOrigin::new(ImmutableOrigin::new_opaque()),
113                base_url.clone(),
114                None,
115                #[cfg(feature = "webgpu")]
116                init.gpu_id_hub.clone(),
117                inherited_secure_context,
118                false,
119                None, // font_context
120            ),
121            base_url,
122            to_script_thread_sender: init.to_script_thread_sender.clone(),
123            executor,
124            pipeline_id,
125        }
126    }
127
128    pub(crate) fn pipeline_id(&self) -> PipelineId {
129        self.pipeline_id
130    }
131
132    /// Evaluate a JS script in this global.
133    pub(crate) fn evaluate_js(
134        &self,
135        script: Cow<'_, str>,
136        cx: &mut JSContext,
137    ) -> Result<(), JavaScriptEvaluationError> {
138        let mut realm = enter_auto_realm(cx, self);
139        let cx = &mut realm.current_realm();
140
141        debug!("Evaluating Dom in a worklet.");
142        self.globalscope.evaluate_js_on_global(
143            cx,
144            script,
145            "",
146            Some(IntroductionType::WORKLET),
147            None,
148        )
149    }
150
151    /// Register a paint worklet to the script thread.
152    pub(crate) fn register_paint_worklet(
153        &self,
154        name: Atom,
155        properties: Vec<Atom>,
156        painter: Box<dyn Painter>,
157    ) {
158        self.to_script_thread_sender
159            .send(MainThreadScriptMsg::RegisterPaintWorklet {
160                pipeline_id: self.globalscope.pipeline_id(),
161                name,
162                properties,
163                painter,
164            })
165            .expect("Worklet thread outlived script thread.");
166    }
167
168    /// The base URL of this global.
169    pub(crate) fn base_url(&self) -> ServoUrl {
170        self.base_url.clone()
171    }
172
173    /// The worklet executor.
174    pub(crate) fn executor(&self) -> WorkletExecutor {
175        self.executor.clone()
176    }
177
178    /// Perform a worklet task
179    pub(crate) fn perform_a_worklet_task(&self, cx: &mut JSContext, task: WorkletTask) {
180        match task {
181            #[cfg(feature = "testbinding")]
182            WorkletTask::Test(task) => match self.downcast::<TestWorkletGlobalScope>() {
183                Some(global) => global.perform_a_worklet_task(task),
184                None => warn!("This is not a test worklet."),
185            },
186            WorkletTask::Paint(task) => match self.downcast::<PaintWorkletGlobalScope>() {
187                Some(global) => global.perform_a_worklet_task(cx, task),
188                None => warn!("This is not a paint worklet."),
189            },
190        }
191    }
192}
193
194/// Resources required by workletglobalscopes
195#[derive(Clone)]
196pub(crate) struct WorkletGlobalScopeInit {
197    /// Channel to the main script thread
198    pub(crate) to_script_thread_sender: Sender<MainThreadScriptMsg>,
199    /// Channel to a resource thread
200    pub(crate) resource_threads: ResourceThreads,
201    /// Channels to the [`StorageThreads`].
202    pub(crate) storage_threads: StorageThreads,
203    /// Channel to the memory profiler
204    pub(crate) mem_profiler_chan: mem::ProfilerChan,
205    /// Channel to the time profiler
206    pub(crate) time_profiler_chan: time::ProfilerChan,
207    /// Channel to devtools
208    pub(crate) devtools_chan: Option<GenericCallback<ScriptToDevtoolsControlMsg>>,
209    /// Messages to send to the Embedder
210    pub(crate) to_embedder_sender: ScriptToEmbedderChan,
211    /// The image cache
212    pub(crate) image_cache: Arc<dyn ImageCache>,
213    /// Identity manager for WebGPU resources
214    #[cfg(feature = "webgpu")]
215    pub(crate) gpu_id_hub: Arc<IdentityHub>,
216    pub(crate) script_to_constellation_sender: ScriptToConstellationSender,
217}
218
219/// <https://drafts.css-houdini.org/worklets/#worklet-global-scope-type>
220#[derive(Clone, Copy, Debug, JSTraceable, MallocSizeOf)]
221pub(crate) enum WorkletGlobalScopeType {
222    /// A servo-specific testing worklet
223    #[cfg(feature = "testbinding")]
224    Test,
225    /// A paint worklet
226    Paint,
227}
228
229/// A task which can be performed in the context of a worklet global.
230pub(crate) enum WorkletTask {
231    #[cfg(feature = "testbinding")]
232    Test(TestWorkletTask),
233    Paint(PaintWorkletTask),
234}
script/dom/worklet/workletglobalscope.rs

script/dom/worklet/
workletglobalscope.rs
