static message_id apply(message_id x) {
CAF_IGNORE_UNUSED(x);
auto result = make_message_id(message_id::upstream_message_category
<< message_id::category_offset);
CAF_ASSERT(x.is_async() || x == result);
return result;
}
bool monitorable_actor::cleanup(error&& reason, execution_unit* host) {
CAF_LOG_TRACE(CAF_ARG(reason));
attachable_ptr head;
bool set_fail_state = exclusive_critical_section([&]() -> bool {
if (!getf(is_cleaned_up_flag)) {
// local actors pass fail_state_ as first argument
if (&fail_state_ != &reason)
fail_state_ = std::move(reason);
attachables_head_.swap(head);
flags(flags() | is_terminated_flag | is_cleaned_up_flag);
on_cleanup();
return true;
}
return false;
});
if (!set_fail_state)
return false;
CAF_LOG_DEBUG("cleanup" << CAF_ARG(id())
<< CAF_ARG(node()) << CAF_ARG(reason));
// send exit messages
for (attachable* i = head.get(); i != nullptr; i = i->next.get())
i->actor_exited(reason, host);
// tell printer to purge its state for us if we ever used aout()
if (getf(abstract_actor::has_used_aout_flag)) {
auto pr = home_system().scheduler().printer();
pr->enqueue(make_mailbox_element(nullptr, make_message_id(), {},
delete_atom::value, id()),
nullptr);
}
return true;
}
void monitorable_actor::add_link(abstract_actor* x) {
// Add backlink on `x` first and add the local attachable only on success.
CAF_LOG_TRACE(CAF_ARG(x));
CAF_ASSERT(x != nullptr);
error fail_state;
bool send_exit_immediately = false;
auto tmp = default_attachable::make_link(address(), x->address());
joined_exclusive_critical_section(this, x, [&] {
if (getf(is_terminated_flag)) {
fail_state = fail_state_;
send_exit_immediately = true;
} else if (x->add_backlink(this)) {
attach_impl(tmp);
}
});
if (send_exit_immediately)
x->enqueue(nullptr, make_message_id(),
make_message(exit_msg{address(), fail_state}), nullptr);
}
bool monitorable_actor::add_backlink(abstract_actor* x) {
// Called in an exclusive critical section.
CAF_LOG_TRACE(CAF_ARG(x));
CAF_ASSERT(x);
error fail_state;
bool send_exit_immediately = false;
default_attachable::observe_token tk{x->address(),
default_attachable::link};
auto tmp = default_attachable::make_link(address(), x->address());
auto success = false;
if (getf(is_terminated_flag)) {
fail_state = fail_state_;
send_exit_immediately = true;
} else if (detach_impl(tk, true, true) == 0) {
attach_impl(tmp);
success = true;
}
if (send_exit_immediately)
x->enqueue(nullptr, make_message_id(),
make_message(exit_msg{address(), fail_state}), nullptr);
return success;
}
