Type Alias mozjs_sys::jsapi::JS::DispatchToEventLoopCallback
source · pub type DispatchToEventLoopCallback = Option<unsafe extern "C" fn(closure: *mut c_void, dispatchable: *mut Dispatchable) -> bool>;Expand description
Callback to dispatch a JS::Dispatchable to a JSContext’s thread’s event loop.
The DispatchToEventLoopCallback set on a particular JSContext must accept
JS::Dispatchable instances and arrange for their run methods to be called
eventually on the JSContext’s thread. This is used for cross-thread dispatch,
so the callback itself must be safe to call from any thread.
If the callback returns true, it must eventually run the given
Dispatchable; otherwise, SpiderMonkey may leak memory or hang.
The callback may return false to indicate that the JSContext’s thread is
shutting down and is no longer accepting runnables. Shutting down is a
one-way transition: once the callback has rejected a runnable, it must reject
all subsequently submitted runnables as well.
To establish a DispatchToEventLoopCallback, the embedding may either call InitDispatchToEventLoop to provide its own, or call js::UseInternalJobQueues to select a default implementation built into SpiderMonkey. This latter depends on the embedding to call js::RunJobs on the JavaScript thread to process queued Dispatchables at appropriate times.
Aliased Type§
enum DispatchToEventLoopCallback {
None,
Some(unsafe extern "C" fn(_: *mut c_void, _: *mut Dispatchable) -> bool),
}