Struct mozjs::rust::Runtime

pub struct Runtime {
    cx: *mut JSContext,
    engine: JSEngineHandle,
    _parent_child_count: Option<Arc<()>>,
    outstanding_children: Arc<()>,
    thread_safe_handle: Arc<RwLock<Option<*mut JSContext>>>,
}

A wrapper for the JSContext structure in SpiderMonkey.

Fields

cx: *mut JSContext

Raw pointer to the underlying SpiderMonkey context.

engine: JSEngineHandle

The engine that this runtime is associated with.

_parent_child_count: Option<Arc<()>>

If this Runtime was created with a parent, this member exists to ensure that that parent’s count of outstanding children (see [outstanding_children]) remains accurate and will be automatically decreased when this Runtime value is dropped.

outstanding_children: Arc<()>

The strong references to this value represent the number of child runtimes that have been created using this Runtime as a parent. Since Runtime values must be associated with a particular thread, we cannot simply use Arc to represent the resulting ownership graph and risk destroying a Runtime on the wrong thread.

thread_safe_handle: Arc<RwLock<Option<*mut JSContext>>>

An Option that holds the same pointer as cx. This is shared with all ThreadSafeJSContexts, so they can detect when it’s destroyed on the main thread.

Implementations

impl Runtime

pub fn get() -> Option<NonNull<JSContext>>

Get the JSContext for this thread.

pub fn thread_safe_js_context(&self) -> ThreadSafeJSContext

Create a ThreadSafeJSContext that can detect when this Runtime is destroyed.

pub fn new(engine: JSEngineHandle) -> Runtime

Creates a new JSContext.

pub fn prepare_for_new_child(&self) -> ParentRuntime

Signal that a new child runtime will be created in the future, and ensure that this runtime will not allow itself to be destroyed before the new child runtime. Returns a handle that can be passed to create_with_parent in order to create a new runtime on another thread that is associated with this runtime.

pub unsafe fn create_with_parent(parent: ParentRuntime) -> Runtime

Creates a new JSContext with a parent runtime. If the parent does not outlive the new runtime, its destructor will assert.

Unsafety: If panicking does not abort the program, any threads with child runtimes will continue executing after the thread with the parent runtime panics, but they will be in an invalid and undefined state.

unsafe fn create( engine: JSEngineHandle, parent: Option<ParentRuntime>, ) -> Runtime

pub fn rt(&self) -> *mut JSRuntime

Returns the JSRuntime object.

pub fn cx(&self) -> *mut JSContext

Returns the JSContext object.

pub fn evaluate_script( &self, glob: HandleObject<'_>, script: &str, filename: &str, line_num: u32, rval: MutableHandleValue<'_>, ) -> Result<(), ()>

Trait Implementations

impl Drop for Runtime

fn drop(&mut self)

Executes the destructor for this type.

impl Traceable for Runtime

unsafe fn trace(&self, _: *mut JSTracer)

Trace self.