void initialize() override {
CAF_LOG_TRACE("");
this->init_broker();
auto bhvr = make_behavior();
CAF_LOG_DEBUG_IF(!bhvr, "make_behavior() did not return a behavior:"
<< CAF_ARG(this->has_behavior()));
if (bhvr) {
// make_behavior() did return a behavior instead of using become()
CAF_LOG_DEBUG("make_behavior() did return a valid behavior");
this->do_become(std::move(bhvr.unbox()), true);
}
}
void event_based_actor::initialize() {
is_initialized(true);
auto bhvr = make_behavior();
CAF_LOG_DEBUG_IF(!bhvr, "make_behavior() did not return a behavior, "
<< "has_behavior() = "
<< std::boolalpha << this->has_behavior());
if (bhvr) {
// make_behavior() did return a behavior instead of using become()
CAF_LOG_DEBUG("make_behavior() did return a valid behavior");
become(std::move(bhvr));
}
}
void initialize() override {
CAF_LOG_TRACE("");
super::initialize();
this->setf(abstract_actor::is_initialized_flag);
auto bhvr = make_behavior();
CAF_LOG_DEBUG_IF(!bhvr, "make_behavior() did not return a behavior:"
<< CAF_ARG2("alive", this->alive()));
if (bhvr) {
// make_behavior() did return a behavior instead of using become()
CAF_LOG_DEBUG("make_behavior() did return a valid behavior");
this->do_become(std::move(bhvr.unbox()), true);
}
}
// go on a raid in quest for a shiny new job
job_ptr raid() {
auto result = m_steal_policy.raid(this);
CAF_LOG_DEBUG_IF(result, "got actor with id " << id_of(result));
return result;
}
/**
* Attempt to steal an element from the exposed job queue.
*/
job_ptr try_steal() override {
auto result = m_queue_policy.try_external_dequeue(this);
CAF_LOG_DEBUG_IF(result, "stole actor with id " << id_of(result));
return result;
}
bool actor_pool::filter(upgrade_lock<detail::shared_spinlock>& guard,
const strong_actor_ptr& sender, message_id mid,
message_view& mv, execution_unit* eu) {
auto& content = mv.content();
CAF_LOG_TRACE(CAF_ARG(mid) << CAF_ARG(content));
if (content.match_elements<exit_msg>()) {
// acquire second mutex as well
std::vector<actor> workers;
auto em = content.get_as<exit_msg>(0).reason;
if (cleanup(std::move(em), eu)) {
auto tmp = mv.move_content_to_message();
// send exit messages *always* to all workers and clear vector afterwards
// but first swap workers_ out of the critical section
upgrade_to_unique_lock<detail::shared_spinlock> unique_guard{guard};
workers_.swap(workers);
unique_guard.unlock();
for (auto& w : workers)
anon_send(w, tmp);
unregister_from_system();
}
return true;
}
if (content.match_elements<down_msg>()) {
// remove failed worker from pool
auto& dm = content.get_as<down_msg>(0);
upgrade_to_unique_lock<detail::shared_spinlock> unique_guard{guard};
auto last = workers_.end();
auto i = std::find(workers_.begin(), workers_.end(), dm.source);
CAF_LOG_DEBUG_IF(i == last, "received down message for an unknown worker");
if (i != last)
workers_.erase(i);
if (workers_.empty()) {
planned_reason_ = exit_reason::out_of_workers;
unique_guard.unlock();
quit(eu);
}
return true;
}
if (content.match_elements<sys_atom, put_atom, actor>()) {
auto& worker = content.get_as<actor>(2);
worker->attach(default_attachable::make_monitor(worker.address(),
address()));
upgrade_to_unique_lock<detail::shared_spinlock> unique_guard{guard};
workers_.push_back(worker);
return true;
}
if (content.match_elements<sys_atom, delete_atom, actor>()) {
upgrade_to_unique_lock<detail::shared_spinlock> unique_guard{guard};
auto& what = content.get_as<actor>(2);
auto last = workers_.end();
auto i = std::find(workers_.begin(), last, what);
if (i != last) {
workers_.erase(i);
}
return true;
}
if (content.match_elements<sys_atom, get_atom>()) {
auto cpy = workers_;
guard.unlock();
sender->enqueue(nullptr, mid.response_id(),
make_message(std::move(cpy)), eu);
return true;
}
if (workers_.empty()) {
guard.unlock();
if (sender && mid.valid()) {
// tell client we have ignored this sync message by sending
// and empty message back
sender->enqueue(nullptr, mid.response_id(), message{}, eu);
}
return true;
}
return false;
}
resumable::resume_result resume(execution_unit* new_host,
size_t max_throughput) override {
CAF_REQUIRE(max_throughput > 0);
auto d = static_cast<Derived*>(this);
CAF_LOG_TRACE("id = " << d->id());
d->host(new_host);
auto done_cb = [&]() -> bool {
CAF_LOG_TRACE("");
d->bhvr_stack().clear();
d->bhvr_stack().cleanup();
d->on_exit();
if (!d->bhvr_stack().empty()) {
CAF_LOG_DEBUG("on_exit did set a new behavior");
d->planned_exit_reason(exit_reason::not_exited);
return false; // on_exit did set a new behavior
}
auto rsn = d->planned_exit_reason();
if (rsn == exit_reason::not_exited) {
rsn = exit_reason::normal;
d->planned_exit_reason(rsn);
}
d->cleanup(rsn);
return true;
};
auto actor_done = [&]() -> bool {
if (d->bhvr_stack().empty()
|| d->planned_exit_reason() != exit_reason::not_exited) {
return done_cb();
}
return false;
};
// actors without behavior or that have already defined
// an exit reason must not be resumed
CAF_REQUIRE(!d->is_initialized()
|| (!d->bhvr_stack().empty()
&& d->planned_exit_reason() == exit_reason::not_exited));
std::exception_ptr eptr = nullptr;
try {
if (!d->is_initialized()) {
CAF_LOG_DEBUG("initialize actor");
d->is_initialized(true);
auto bhvr = d->make_behavior();
CAF_LOG_DEBUG_IF(!bhvr, "make_behavior() did not return a behavior, "
<< "bhvr_stack().empty() = "
<< std::boolalpha << d->bhvr_stack().empty());
if (bhvr) {
// make_behavior() did return a behavior instead of using become()
CAF_LOG_DEBUG("make_behavior() did return a valid behavior");
d->become(std::move(bhvr));
}
if (actor_done()) {
CAF_LOG_DEBUG("actor_done() returned true right "
<< "after make_behavior()");
return resume_result::done;
}
}
// max_throughput = 0 means infinite
for (size_t i = 0; i < max_throughput; ++i) {
auto ptr = d->next_message();
if (ptr) {
if (d->invoke_message(ptr)) {
if (actor_done()) {
CAF_LOG_DEBUG("actor exited");
return resume_result::done;
}
// continue from cache if current message was
// handled, because the actor might have changed
// its behavior to match 'old' messages now
while (d->invoke_message_from_cache()) {
if (actor_done()) {
CAF_LOG_DEBUG("actor exited");
return resume_result::done;
}
}
}
// add ptr to cache if invoke_message
// did not reset it (i.e. skipped, but not dropped)
if (ptr) {
CAF_LOG_DEBUG("add message to cache");
d->push_to_cache(std::move(ptr));
}
} else {
CAF_LOG_DEBUG("no more element in mailbox; going to block");
if (d->mailbox().try_block()) {
return resumable::awaiting_message;
}
CAF_LOG_DEBUG("try_block() interrupted by new message");
}
}
if (!d->has_next_message() && d->mailbox().try_block()) {
return resumable::awaiting_message;
}
// time's up
return resumable::resume_later;
}
catch (actor_exited& what) {
CAF_LOG_INFO("actor died because of exception: actor_exited, "
"reason = " << what.reason());
if (d->exit_reason() == exit_reason::not_exited) {
d->quit(what.reason());
}
}
catch (std::exception& e) {
CAF_LOG_INFO("actor died because of an exception: "
<< detail::demangle(typeid(e))
<< ", what() = " << e.what());
if (d->exit_reason() == exit_reason::not_exited) {
d->quit(exit_reason::unhandled_exception);
}
eptr = std::current_exception();
}
catch (...) {
CAF_LOG_INFO("actor died because of an unknown exception");
if (d->exit_reason() == exit_reason::not_exited) {
d->quit(exit_reason::unhandled_exception);
}
eptr = std::current_exception();
}
if (eptr) {
auto opt_reason = d->handle(eptr);
if (opt_reason) {
// use exit reason defined by custom handler
d->planned_exit_reason(*opt_reason);
}
}
if (!actor_done()) {
// actor has been "revived", try running it again later
return resumable::resume_later;
}
return resumable::done;
}
handle_message_result handle_message(Actor* self, mailbox_element* node,
Fun& fun, message_id awaited_response) {
bool handle_sync_failure_on_mismatch = true;
if (dptr()->hm_should_skip(node)) {
return hm_skip_msg;
}
switch (this->filter_msg(self, node)) {
case msg_type::normal_exit:
CAF_LOG_DEBUG("dropped normal exit signal");
return hm_drop_msg;
case msg_type::expired_sync_response:
CAF_LOG_DEBUG("dropped expired sync response");
return hm_drop_msg;
case msg_type::expired_timeout:
CAF_LOG_DEBUG("dropped expired timeout message");
return hm_drop_msg;
case msg_type::inactive_timeout:
CAF_LOG_DEBUG("skipped inactive timeout message");
return hm_skip_msg;
case msg_type::non_normal_exit:
CAF_LOG_DEBUG("handled non-normal exit signal");
// this message was handled
// by calling self->quit(...)
return hm_msg_handled;
case msg_type::timeout: {
CAF_LOG_DEBUG("handle timeout message");
auto& tm = node->msg.get_as<timeout_msg>(0);
self->handle_timeout(fun, tm.timeout_id);
if (awaited_response.valid()) {
self->mark_arrived(awaited_response);
self->remove_handler(awaited_response);
}
return hm_msg_handled;
}
case msg_type::timeout_response:
handle_sync_failure_on_mismatch = false;
CAF_ANNOTATE_FALLTHROUGH;
case msg_type::sync_response:
CAF_LOG_DEBUG("handle as synchronous response: "
<< CAF_TARG(node->msg, to_string) << ", "
<< CAF_MARG(node->mid, integer_value) << ", "
<< CAF_MARG(awaited_response, integer_value));
if (awaited_response.valid() && node->mid == awaited_response) {
auto previous_node = dptr()->hm_begin(self, node);
auto res = invoke_fun(self, node->msg, node->mid, fun);
if (!res && handle_sync_failure_on_mismatch) {
CAF_LOG_WARNING("sync failure occured in actor "
<< "with ID " << self->id());
self->handle_sync_failure();
}
self->mark_arrived(awaited_response);
self->remove_handler(awaited_response);
dptr()->hm_cleanup(self, previous_node);
return hm_msg_handled;
}
return hm_cache_msg;
case msg_type::ordinary:
if (!awaited_response.valid()) {
auto previous_node = dptr()->hm_begin(self, node);
auto res = invoke_fun(self, node->msg, node->mid, fun);
if (res) {
dptr()->hm_cleanup(self, previous_node);
return hm_msg_handled;
}
// no match (restore self members)
dptr()->hm_revert(self, previous_node);
}
CAF_LOG_DEBUG_IF(awaited_response.valid(),
"ignored message; await response: "
<< awaited_response.integer_value());
return hm_cache_msg;
}
// should be unreachable
CAF_CRITICAL("invalid message type");
}
optional<message> invoke_fun(Actor* self, message& msg, message_id& mid,
Fun& fun,
MaybeResponseHdl hdl = MaybeResponseHdl{}) {
# ifdef CAF_LOG_LEVEL
auto msg_str = to_string(msg);
# endif
CAF_LOG_TRACE(CAF_MARG(mid, integer_value) << ", msg = " << msg_str);
auto res = fun(msg); // might change mid
CAF_LOG_DEBUG_IF(res, "actor did consume message: " << msg_str);
CAF_LOG_DEBUG_IF(!res, "actor did ignore message: " << msg_str);
if (!res) {
return none;
}
if (res->empty()) {
// make sure synchronous requests
// always receive a response
if (mid.is_request() && !mid.is_answered()) {
CAF_LOG_WARNING("actor with ID " << self->id()
<< " did not reply to a synchronous request message");
auto fhdl = fetch_response_promise(self, hdl);
if (fhdl) {
fhdl.deliver(make_message(unit));
}
}
} else {
CAF_LOGF_DEBUG("res = " << to_string(*res));
if (res->template has_types<atom_value, uint64_t>()
&& res->template get_as<atom_value>(0) == atom("MESSAGE_ID")) {
CAF_LOG_DEBUG("message handler returned a message id wrapper");
auto id = res->template get_as<uint64_t>(1);
auto msg_id = message_id::from_integer_value(id);
auto ref_opt = self->sync_handler(msg_id);
// calls self->response_promise() if hdl is a dummy
// argument, forwards hdl otherwise to reply to the
// original request message
auto fhdl = fetch_response_promise(self, hdl);
if (ref_opt) {
behavior cpy = *ref_opt;
*ref_opt =
cpy.add_continuation([=](message & intermediate)
->optional<message> {
if (!intermediate.empty()) {
// do no use lamba expresion type to
// avoid recursive template instantiaton
behavior::continuation_fun f2 = [=](
message & m)->optional<message> {
return std::move(m);
};
auto mutable_mid = mid;
// recursively call invoke_fun on the
// result to correctly handle stuff like
// sync_send(...).then(...).then(...)...
return this->invoke_fun(self, intermediate,
mutable_mid, f2, fhdl);
}
return none;
});
}
// reset res to prevent "outer" invoke_fun
// from handling the result again
res->reset();
} else {
// respond by using the result of 'fun'
CAF_LOG_DEBUG("respond via response_promise");
auto fhdl = fetch_response_promise(self, hdl);
if (fhdl) {
fhdl.deliver(std::move(*res));
// inform caller about success
return message{};
}
}
}
return res;
}