concurrent(Args&&... args)
: _worker(std::forward<Args>(args)...)
, _done(false)
, _thd([ = ]{concurrent_helper::Callback call;
while (!_done) { _q.wait_and_pop(call); call();
}}) {
}
void run() const {
concurrent_helper::Callback call;
while (!_done) {
_q.wait_and_pop(call);
call();
}
}
void fire(AsyncCall func, Args&& ... args) const noexcept(false) {
if (empty()) {
throw std::runtime_error("nullptr instantiated worker");
}
// weak compiler support for expanding parameter pack in a lambda. std::function is the
// work-around, With better compiler support it can be changed to:
// auto bgCall = [&, args...]{ return (_worker.*func)(args...); };
auto bgCall = std::bind(func, _worker.get(), std::forward<Args>(args)...);
_q.push(bgCall);
return;
}
/**
* Moves in a unique_ptr<T> to be the background object. Starts up the worker thread
* @param worker to act as the background object
*/
concurrent(std::unique_ptr<T> worker)
: _worker(std::move(worker))
, _done(false)
, _thd([ = ] {
concurrent_helper::Callback call;
while (_worker && !_done) {
_q.wait_and_pop(call);
call();
}
}) {
}
/// return snapshot of size
virtual size_t size() { return _q.size(); }
/**
* Clean shutdown. All pending messages are executed before the shutdown message is received
*/
virtual ~concurrent() {
_q.push([ = ] {_done = true;});
if (_thd.joinable()) {
_thd.join();
}
}
~concurrent() {
_q.push([ = ]{_done = true;});
_thd.join();
}