Trigger worker run

start-worker-run.cc

void Worker::StartThread(const FunctionCallbackInfo<Value>& args) {
  Worker* w;
  ASSIGN_OR_RETURN_UNWRAP(&w, args.This());
  Mutex::ScopedLock lock(w->mutex_);

  // The object now owns the created thread and should not be garbage collected
  // until that finishes.
  w->ClearWeak();

  w->env()->add_sub_worker_context(w);
  w->stopped_ = false;
  w->thread_joined_ = false;

  w->on_thread_finished_.Install(w->env(), w, [](uv_async_t* handle) {
    Worker* w_ = static_cast<Worker*>(handle->data);
    CHECK(w_->is_stopped());
    w_->parent_port_ = nullptr;
    w_->JoinThread();
    delete w_;
  });

  uv_thread_options_t thread_options;
  thread_options.flags = UV_THREAD_HAS_STACK_SIZE;
  thread_options.stack_size = kStackSize;
  CHECK_EQ(uv_thread_create_ex(&w->tid_, &thread_options, [](void* arg) {
    Worker* w = static_cast<Worker*>(arg);
    const uintptr_t stack_top = reinterpret_cast<uintptr_t>(&arg);

    // Leave a few kilobytes just to make sure we're within limits and have
    // some space to do work in C++ land.
    w->stack_base_ = stack_top - (kStackSize - kStackBufferSize);

    w->Run();

    Mutex::ScopedLock lock(w->mutex_);
    w->on_thread_finished_.Stop();
  }, static_cast<void*>(w)), 0);
}