Can quickjs be used in multithreading?

[penneryu]

static JSClassID js_class_id_alloc = JS_CLASS_INIT_COUNT;

/* a new class ID is allocated if *pclass_id != 0 */
JSClassID JS_NewClassID(JSClassID *pclass_id)
{
    JSClassID class_id;
#ifdef CONFIG_ATOMICS
    pthread_mutex_lock(&js_class_id_mutex);
#endif
    class_id = *pclass_id;
    if (class_id == 0) {
        class_id = js_class_id_alloc++;
        *pclass_id = class_id;
    }
#ifdef CONFIG_ATOMICS
    pthread_mutex_unlock(&js_class_id_mutex);
#endif
    return class_id;
}

As shown in the code above, js_class_id_alloc is a global variable, and the same reference is used in all threads.
If different JSRuntimes are instantiated in different threads, and JS_NewClassID is called in each thread to generate a new classId, then the classId will not grow independently in each thread as expected, which should cause management problems for class_array in each JSRuntime.

ps: In addition, I found that calling quickjs API in multiple threads will cause some resource management problems, even in different JSRuntime instances.

[bnoordhuis]

I don't know if Charlie and Fabrice intend to cherry-pick it but we fixed that in quickjs-ng almost a year ago to the day in commit quickjs-ng/quickjs@5ce2957e.

[penneryu]

I don't know if Charlie and Fabrice intend to cherry-pick it but we fixed that in quickjs-ng almost a year ago to the day in commit quickjs-ng/quickjs@5ce2957e.

thanks, I think this modification is good, classid is originally bound to the runtime, so creating a new one should not affect other runtimes.

[chqrlie]

Yes, we shall cherry-pick this patch and many others