C++ EventableDescriptor::ScheduleClose方法代码示例

void ConnectionDescriptor::CloseConnection (const char *binding, bool after_writing)
{
	// TODO: This is something of a hack, or at least it's a static method of the wrong class.
	EventableDescriptor *ed = dynamic_cast <EventableDescriptor*> (Bindable_t::GetObject (binding));
	if (ed)
		ed->ScheduleClose (after_writing);
}

extern "C" void evma_close_connection (const unsigned long binding, int after_writing)
{
	ensure_eventmachine("evma_close_connection");
	EventableDescriptor *ed = dynamic_cast <EventableDescriptor*> (Bindable_t::GetObject (binding));
	if (ed)
		ed->ScheduleClose (after_writing ? true : false);
}

bool EventMachine_t::_RunEpollOnce()
{
	#ifdef HAVE_EPOLL
	assert (epfd != -1);
	struct epoll_event ev [MaxEpollDescriptors];
	int s = epoll_wait (epfd, ev, MaxEpollDescriptors, 50);
	if (s > 0) {
		for (int i=0; i < s; i++) {
			EventableDescriptor *ed = (EventableDescriptor*) ev[i].data.ptr;

			if (ev[i].events & (EPOLLERR | EPOLLHUP))
				ed->ScheduleClose (false);
			if (ev[i].events & EPOLLIN)
				ed->Read();
			if (ev[i].events & EPOLLOUT) {
				ed->Write();
				epoll_ctl (epfd, EPOLL_CTL_MOD, ed->GetSocket(), ed->GetEpollEvent());
				// Ignoring return value
			}
		}
	}
	else if (s < 0) {
		// epoll_wait can fail on error in a handful of ways.
		// If this happens, then wait for a little while to avoid busy-looping.
		// If the error was EINTR, we probably caught SIGCHLD or something,
		// so keep the wait short.
		timeval tv = {0, ((errno == EINTR) ? 5 : 50) * 1000};
		EmSelect (0, NULL, NULL, NULL, &tv);
	}

	{ // cleanup dying sockets
		// vector::pop_back works in constant time.
		// TODO, rip this out and only delete the descriptors we know have died,
		// rather than traversing the whole list.
		//  Modified 05Jan08 per suggestions by Chris Heath. It's possible that
		//  an EventableDescriptor will have a descriptor value of -1. That will
		//  happen if EventableDescriptor::Close was called on it. In that case,
		//  don't call epoll_ctl to remove the socket's filters from the epoll set.
		//  According to the epoll docs, this happens automatically when the
		//  descriptor is closed anyway. This is different from the case where
		//  the socket has already been closed but the descriptor in the ED object
		//  hasn't yet been set to INVALID_SOCKET.
		int i, j;
		int nSockets = Descriptors.size();
		for (i=0, j=0; i < nSockets; i++) {
			EventableDescriptor *ed = Descriptors[i];
			assert (ed);
			if (ed->ShouldDelete()) {
				if (ed->GetSocket() != INVALID_SOCKET) {
					assert (bEpoll); // wouldn't be in this method otherwise.
					assert (epfd != -1);
					int e = epoll_ctl (epfd, EPOLL_CTL_DEL, ed->GetSocket(), ed->GetEpollEvent());
					// ENOENT or EBADF are not errors because the socket may be already closed when we get here.
					if (e && (errno != ENOENT) && (errno != EBADF)) {
						char buf [200];
						snprintf (buf, sizeof(buf)-1, "unable to delete epoll event: %s", strerror(errno));
						throw std::runtime_error (buf);
					}
				}

				ModifiedDescriptors.erase (ed);
				delete ed;
			}
			else
				Descriptors [j++] = ed;
		}
		while ((size_t)j < Descriptors.size())
			Descriptors.pop_back();

	}

	// TODO, heartbeats.
	// Added 14Sep07, its absence was noted by Brian Candler. But the comment was here, indicated
	// that this got thought about and not done when EPOLL was originally written. Was there a reason
	// not to do it, or was it an oversight? Certainly, running a heartbeat on 50,000 connections every
	// two seconds can get to be a real bear, especially if all we're doing is timing out dead ones.
	// Maybe there's a better way to do this. (Or maybe it's not that expensive after all.)
	//
	{ // dispatch heartbeats
		if (gCurrentLoopTime >= NextHeartbeatTime) {
			NextHeartbeatTime = gCurrentLoopTime + HeartbeatInterval;

			for (int i=0; i < Descriptors.size(); i++) {
				EventableDescriptor *ed = Descriptors[i];
				assert (ed);
				ed->Heartbeat();
			}
		}
	}

	timeval tv = {0,0};
	EmSelect (0, NULL, NULL, NULL, &tv);

	return true;
	#else
	throw std::runtime_error ("epoll is not implemented on this platform");
	#endif
}