script/dom/
abortsignal.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::cell::{Cell, RefCell};
6use std::rc::Rc;
7use std::sync::{Arc, Mutex};
8
9use dom_struct::dom_struct;
10use indexmap::IndexSet;
11use js::context::JSContext;
12use js::jsapi::{ExceptionStackBehavior, Heap};
13use js::jsval::{JSVal, UndefinedValue};
14use js::realm::CurrentRealm;
15use js::rust::wrappers2::JS_SetPendingException;
16use js::rust::{HandleObject, HandleValue, MutableHandleValue};
17use script_bindings::inheritance::Castable;
18use script_bindings::weakref::WeakRef;
19
20use crate::dom::bindings::cell::DomRefCell;
21use crate::dom::bindings::codegen::Bindings::AbortSignalBinding::AbortSignalMethods;
22use crate::dom::bindings::codegen::Bindings::EventListenerBinding::EventListener;
23use crate::dom::bindings::codegen::Bindings::EventTargetBinding::EventListenerOptions;
24use crate::dom::bindings::error::{Error, ErrorToJsval, Fallible};
25use crate::dom::bindings::refcounted::Trusted;
26use crate::dom::bindings::reflector::{DomGlobal, reflect_dom_object_with_proto};
27use crate::dom::bindings::root::{Dom, DomRoot};
28use crate::dom::bindings::str::DOMString;
29use crate::dom::eventtarget::EventTarget;
30use crate::dom::globalscope::GlobalScope;
31use crate::dom::readablestream::PipeTo;
32use crate::fetch::{DeferredFetchRecordId, FetchContext};
33use crate::realms::enter_auto_realm;
34use crate::script_runtime::{CanGc, JSContext as SafeJSContext};
35
36impl js::gc::Rootable for AbortAlgorithm {}
37
38/// <https://dom.spec.whatwg.org/#abortcontroller-api-integration>
39/// TODO: implement algorithms at call point,
40/// in order to integrate the abort signal with its various use cases.
41#[derive(Clone, JSTraceable, MallocSizeOf)]
42#[cfg_attr(crown, crown::unrooted_must_root_lint::must_root)]
43pub(crate) enum AbortAlgorithm {
44    /// <https://dom.spec.whatwg.org/#add-an-event-listener>
45    DomEventListener(RemovableDomEventListener),
46    /// <https://streams.spec.whatwg.org/#readable-stream-pipe-to>
47    StreamPiping(PipeTo),
48    /// <https://fetch.spec.whatwg.org/#dom-global-fetch>
49    Fetch(
50        #[no_trace]
51        #[conditional_malloc_size_of]
52        Arc<Mutex<Option<FetchContext>>>,
53    ),
54    /// <https://fetch.spec.whatwg.org/#dom-window-fetchlater>
55    FetchLater(#[no_trace] DeferredFetchRecordId),
56}
57
58#[derive(Clone, JSTraceable, MallocSizeOf)]
59#[cfg_attr(crown, crown::unrooted_must_root_lint::must_root)]
60pub(crate) struct RemovableDomEventListener {
61    pub(crate) event_target: Dom<EventTarget>,
62    pub(crate) ty: DOMString,
63    #[conditional_malloc_size_of]
64    pub(crate) listener: Option<Rc<EventListener>>,
65    pub(crate) options: EventListenerOptions,
66}
67
68/// <https://dom.spec.whatwg.org/#abortsignal>
69#[dom_struct]
70pub(crate) struct AbortSignal {
71    eventtarget: EventTarget,
72
73    /// <https://dom.spec.whatwg.org/#abortsignal-abort-reason>
74    #[ignore_malloc_size_of = "mozjs"]
75    abort_reason: Heap<JSVal>,
76
77    /// <https://dom.spec.whatwg.org/#abortsignal-abort-algorithms>
78    abort_algorithms: RefCell<Vec<AbortAlgorithm>>,
79
80    /// <https://dom.spec.whatwg.org/#abortsignal-dependent>
81    dependent: Cell<bool>,
82
83    /// <https://dom.spec.whatwg.org/#abortsignal-source-signals>
84    #[no_trace]
85    #[ignore_malloc_size_of = "WeakRef"]
86    source_signals: DomRefCell<IndexSet<WeakRef<AbortSignal>>>,
87
88    /// <https://dom.spec.whatwg.org/#abortsignal-dependent-signals>
89    #[no_trace]
90    #[ignore_malloc_size_of = "WeakRef"]
91    dependent_signals: DomRefCell<IndexSet<WeakRef<AbortSignal>>>,
92}
93
94impl AbortSignal {
95    fn new_inherited() -> AbortSignal {
96        AbortSignal {
97            eventtarget: EventTarget::new_inherited(),
98            abort_reason: Default::default(),
99            abort_algorithms: Default::default(),
100            dependent: Default::default(),
101            source_signals: Default::default(),
102            dependent_signals: Default::default(),
103        }
104    }
105
106    pub(crate) fn new_with_proto(
107        global: &GlobalScope,
108        proto: Option<HandleObject>,
109        can_gc: CanGc,
110    ) -> DomRoot<AbortSignal> {
111        reflect_dom_object_with_proto(
112            Box::new(AbortSignal::new_inherited()),
113            global,
114            proto,
115            can_gc,
116        )
117    }
118
119    /// <https://dom.spec.whatwg.org/#abortsignal-signal-abort>
120    pub(crate) fn signal_abort(&self, cx: &mut CurrentRealm, reason: HandleValue) {
121        let global = self.global();
122
123        // Step 1. If signal is aborted, then return.
124        if self.Aborted() {
125            return;
126        }
127
128        // Step 2. Set signal’s abort reason to reason if it is given;
129        // otherwise to a new "AbortError" DOMException.
130        let abort_reason = reason.get();
131        if !abort_reason.is_undefined() {
132            self.abort_reason.set(abort_reason);
133        } else {
134            rooted!(&in(cx) let mut rooted_error = UndefinedValue());
135            Error::Abort(None).to_jsval(
136                cx.into(),
137                &global,
138                rooted_error.handle_mut(),
139                CanGc::from_cx(cx),
140            );
141            self.abort_reason.set(rooted_error.get())
142        }
143
144        // Step 3. Let dependentSignalsToAbort be a new list.
145        let mut dependent_signals_to_abort = vec![];
146
147        // Step 4. For each dependentSignal of signal’s dependent signals:
148        for weak in self.dependent_signals.borrow().iter() {
149            if let Some(dependent_signal) = weak.root() {
150                // Step 4.1. If dependentSignal is not aborted:
151                if !dependent_signal.aborted() {
152                    // Step 4.1.1. Set dependentSignal’s abort reason to signal’s abort reason.
153                    dependent_signal.abort_reason.set(self.abort_reason.get());
154                    // Step 4.1.2. Append dependentSignal to dependentSignalsToAbort.
155                    dependent_signals_to_abort.push(dependent_signal);
156                }
157            }
158        }
159
160        // Step 5. Run the abort steps for signal.
161        self.run_the_abort_steps(cx, &global);
162
163        // Step 6. For each dependentSignal of dependentSignalsToAbort, run the abort steps for dependentSignal.
164        for dependent_signal in dependent_signals_to_abort.iter() {
165            dependent_signal.run_the_abort_steps(cx, &global);
166        }
167    }
168
169    /// <https://dom.spec.whatwg.org/#abortsignal-add>
170    pub(crate) fn add(&self, algorithm: &AbortAlgorithm) {
171        // Step 1. If signal is aborted, then return.
172        if self.aborted() {
173            return;
174        }
175
176        // Step 2. Append algorithm to signal’s abort algorithms.
177        self.abort_algorithms.borrow_mut().push(algorithm.clone());
178
179        // if this is a dependent signal, it may now need to be kept alive.
180        if self.dependent.get() {
181            self.global().register_dependent_abort_signal(self);
182        }
183    }
184
185    /// Run a specific abort algorithm.
186    pub(crate) fn run_abort_algorithm(
187        &self,
188        cx: &mut CurrentRealm,
189        global: &GlobalScope,
190        algorithm: &AbortAlgorithm,
191    ) {
192        match algorithm {
193            AbortAlgorithm::StreamPiping(pipe) => {
194                rooted!(&in(cx) let mut reason = UndefinedValue());
195                reason.set(self.abort_reason.get());
196                pipe.abort_with_reason(cx, global, reason.handle());
197            },
198            AbortAlgorithm::Fetch(fetch_context) => {
199                rooted!(&in(cx) let mut reason = UndefinedValue());
200                reason.set(self.abort_reason.get());
201                if let Some(fetch_context) = &mut *fetch_context.lock().unwrap() {
202                    fetch_context.abort_fetch(reason.handle(), cx);
203                }
204            },
205            AbortAlgorithm::FetchLater(deferred_fetch_record_id) => {
206                global
207                    .deferred_fetch_record_for_id(deferred_fetch_record_id)
208                    .abort();
209            },
210            AbortAlgorithm::DomEventListener(removable_listener) => {
211                removable_listener.event_target.remove_event_listener(
212                    removable_listener.ty.clone(),
213                    &removable_listener.listener,
214                    &removable_listener.options,
215                );
216            },
217        }
218    }
219
220    /// <https://dom.spec.whatwg.org/#run-the-abort-steps>
221    fn run_the_abort_steps(&self, cx: &mut CurrentRealm, global: &GlobalScope) {
222        // Step 1. For each algorithm of signal’s abort algorithms: run algorithm.
223        for algo in self.abort_algorithms.borrow().iter() {
224            self.run_abort_algorithm(cx, global, algo);
225        }
226        // Step 2. Empty signal’s abort algorithms.
227        self.abort_algorithms.borrow_mut().clear();
228
229        // Step 3. Fire an event named abort at signal.
230        self.upcast::<EventTarget>().fire_event(cx, atom!("abort"));
231    }
232
233    /// <https://dom.spec.whatwg.org/#abortsignal-aborted>
234    pub(crate) fn aborted(&self) -> bool {
235        // An AbortSignal object is aborted when its abort reason is not undefined.
236        !self.abort_reason.get().is_undefined()
237    }
238
239    /// <https://dom.spec.whatwg.org/#create-a-dependent-abort-signal>
240    pub(crate) fn create_dependent_abort_signal(
241        signals: Vec<DomRoot<AbortSignal>>,
242        global: &GlobalScope,
243        can_gc: CanGc,
244    ) -> DomRoot<AbortSignal> {
245        // Step 1. Let resultSignal be a new object implementing signalInterface using realm.
246        let result_signal = Self::new_with_proto(global, None, can_gc);
247        // Step 2. For each signal of signals: if signal is aborted,
248        // then set resultSignal’s abort reason to signal’s abort reason and return resultSignal.
249        for signal in signals.iter() {
250            if signal.aborted() {
251                result_signal.abort_reason.set(signal.abort_reason.get());
252                return result_signal;
253            }
254        }
255        // Step 3. Set resultSignal’s dependent to true.
256        result_signal.dependent.set(true);
257        // Step 4. For each signal of signals:
258        for signal in signals.iter() {
259            // Step 4.1. If signal’s dependent is false:
260            if !signal.dependent.get() {
261                // Step 4.1.1. Append signal to resultSignal’s source signals.
262                result_signal
263                    .source_signals
264                    .borrow_mut()
265                    .insert(WeakRef::new(signal));
266                // Step 4.1.2. Append resultSignal to signal’s dependent signals.
267                signal
268                    .dependent_signals
269                    .borrow_mut()
270                    .insert(WeakRef::new(&*result_signal));
271            } else {
272                // Step 4.2. Otherwise, for each sourceSignal of signal’s source signals:
273                for source_signal_weak in signal.source_signals.borrow().iter() {
274                    if let Some(source_signal) = source_signal_weak.root() {
275                        // Step 4.2.1. Assert: sourceSignal is not aborted and not dependent.
276                        assert!(!source_signal.aborted() && !source_signal.dependent.get());
277                        // Step 4.2.2. Append sourceSignal to resultSignal’s source signals.
278                        result_signal
279                            .source_signals
280                            .borrow_mut()
281                            .insert(WeakRef::new(&*source_signal));
282                        // Step 4.2.3. Append resultSignal to sourceSignal’s dependent signals.
283                        source_signal
284                            .dependent_signals
285                            .borrow_mut()
286                            .insert(WeakRef::new(&*result_signal));
287                    }
288                }
289            }
290        }
291        // Step 5. Return resultSignal.
292        global.register_dependent_abort_signal(&result_signal);
293        result_signal
294    }
295
296    /// Remove weak references whose target has been collected.
297    fn prune_dead_weak_refs(&self) {
298        self.source_signals.borrow_mut().retain(|w| w.is_alive());
299        self.dependent_signals.borrow_mut().retain(|w| w.is_alive());
300    }
301
302    /// Whether this signal still has abort algorithms registered.
303    fn has_abort_algorithms(&self) -> bool {
304        !self.abort_algorithms.borrow().is_empty()
305    }
306
307    /// Whether this signal has any listeners for its "abort" event.
308    fn has_abort_listeners(&self) -> bool {
309        self.upcast::<EventTarget>()
310            .has_listeners_for(&atom!("abort"))
311    }
312
313    /// <https://dom.spec.whatwg.org/#abort-signal-garbage-collection>
314    /// A non-aborted dependent AbortSignal object must not be garbage
315    /// collected while its source signals is non-empty and it has
316    /// registered event listeners for its abort event or its abort
317    /// algorithms is non-empty.
318    pub(crate) fn must_keep_alive_for_gc(&self) -> bool {
319        // Treat dead weak entries as removed.
320        self.prune_dead_weak_refs();
321
322        // Only care about non-aborted signals.
323        if self.aborted() {
324            return false;
325        }
326
327        // If it has no live source signals left, it doesn’t need to be kept.
328        if self.source_signals.borrow().is_empty() {
329            return false;
330        }
331
332        let has_algos = self.has_abort_algorithms();
333        let has_listeners = self.has_abort_listeners();
334
335        has_algos || has_listeners
336    }
337}
338
339impl AbortSignalMethods<crate::DomTypeHolder> for AbortSignal {
340    /// <https://dom.spec.whatwg.org/#dom-abortsignal-aborted>
341    fn Aborted(&self) -> bool {
342        // The aborted getter steps are to return true if this is aborted; otherwise false.
343        self.aborted()
344    }
345
346    /// <https://dom.spec.whatwg.org/#dom-abortsignal-abort>
347    fn Abort(
348        cx: SafeJSContext,
349        global: &GlobalScope,
350        reason: HandleValue,
351        can_gc: CanGc,
352    ) -> DomRoot<AbortSignal> {
353        // Step 1. Let signal be a new AbortSignal object.
354        let signal = AbortSignal::new_with_proto(global, None, can_gc);
355
356        // Step 2. Set signal’s abort reason to reason if it is given;
357        // otherwise to a new "AbortError" DOMException.
358        let abort_reason = reason.get();
359        if !abort_reason.is_undefined() {
360            signal.abort_reason.set(abort_reason);
361        } else {
362            rooted!(in(*cx) let mut rooted_error = UndefinedValue());
363            Error::Abort(None).to_jsval(cx, global, rooted_error.handle_mut(), can_gc);
364            signal.abort_reason.set(rooted_error.get())
365        }
366
367        // Step 3. Return signal.
368        signal
369    }
370
371    /// <https://dom.spec.whatwg.org/#dom-abortsignal-timeout>
372    fn Timeout(global: &GlobalScope, milliseconds: u64, can_gc: CanGc) -> DomRoot<AbortSignal> {
373        // Step 1. Let signal be a new AbortSignal object.
374        let signal = AbortSignal::new_with_proto(global, None, can_gc);
375
376        // Step 2. Let global be signal’s relevant global object.
377        // We already have `global`.
378
379        let signal_keepalive: Trusted<AbortSignal> = Trusted::new(&signal);
380
381        let ms_i64 = if milliseconds > i64::MAX as u64 {
382            i64::MAX
383        } else {
384            milliseconds as i64
385        };
386
387        // Step 3. Run steps after a timeout given global, "AbortSignal-timeout", milliseconds, and the following step:
388        global.run_steps_after_a_timeout(
389            DOMString::from("AbortSignal-timeout"),
390            ms_i64,
391            move |_cx, global| {
392                let task_source = global.task_manager().timer_task_source().to_sendable();
393
394                // Step 3.1. Queue a global task on the timer task source given global to signal abort given signal and a new "TimeoutError" DOMException.
395                // For the duration of this timeout, if signal has any event listeners registered for its abort event,
396                // there must be a strong reference from global to signal.
397                task_source.queue(task!(abortsignal_timeout: move |cx| {
398                    let signal_for_task = signal_keepalive.root();
399
400                    rooted!(&in(cx) let mut reason = UndefinedValue());
401                    Error::Timeout(None).to_jsval(
402                        cx.into(),
403                        &signal_for_task.global(),
404                        reason.handle_mut(),
405                        CanGc::from_cx(cx),
406                    );
407
408                    let mut realm = enter_auto_realm(cx, &*signal_for_task.global());
409                    let mut realm = realm.current_realm();
410
411                    // “signal abort given signal and a new "TimeoutError" DOMException.”
412                    signal_for_task.signal_abort(
413                        &mut realm,
414                        reason.handle(),
415                    );
416                }));
417            },
418        );
419
420        // Step 4. Return signal.
421        signal
422    }
423
424    /// <https://dom.spec.whatwg.org/#dom-abortsignal-any>
425    fn Any(
426        global: &GlobalScope,
427        signals: Vec<DomRoot<AbortSignal>>,
428        can_gc: CanGc,
429    ) -> DomRoot<AbortSignal> {
430        // The static any(signals) method steps are to return the result
431        // of creating a dependent abort signal from signals using AbortSignal and the current realm.
432        Self::create_dependent_abort_signal(signals, global, can_gc)
433    }
434
435    /// <https://dom.spec.whatwg.org/#dom-abortsignal-reason>
436    fn Reason(&self, _cx: SafeJSContext, mut rval: MutableHandleValue) {
437        // The reason getter steps are to return this’s abort reason.
438        rval.set(self.abort_reason.get());
439    }
440
441    /// <https://dom.spec.whatwg.org/#dom-abortsignal-throwifaborted>
442    #[expect(unsafe_code)]
443    fn ThrowIfAborted(&self, cx: &mut JSContext) -> Fallible<()> {
444        // The throwIfAborted() method steps are to throw this’s abort reason, if this is aborted.
445        if self.aborted() {
446            unsafe {
447                JS_SetPendingException(
448                    cx,
449                    HandleValue::from_raw(self.abort_reason.handle()),
450                    ExceptionStackBehavior::Capture,
451                )
452            };
453            return Err(Error::JSFailed);
454        }
455        Ok(())
456    }
457
458    // <https://dom.spec.whatwg.org/#dom-abortsignal-onabort>
459    event_handler!(abort, GetOnabort, SetOnabort);
460}
script/dom/abortsignal.rs

script/dom/
abortsignal.rs
