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[maksis <maksis@xxxxxxxxxxxxxxxxxxxxxx>]

updateCounts is not thread safe what comes to counting the hubs
correctly.

	if(countType != COUNT_UNCOUNTED) {
		--counts[countType];
		countType = COUNT_UNCOUNTED;
	}

When two threads access that function simultaneously, the second thread
may see the type as uncounted because it has been changed by the first
thread. This means that the second thread won't decrease the hub count
as it should.


	if(!aRemove) {
		if(getMyIdentity().isOp()) {
			countType = COUNT_OP;
		} else if(getMyIdentity().isRegistered()) {
			countType = COUNT_REGISTERED;
		} else {
			countType = COUNT_NORMAL;
		}
		++counts[countType];
	}

The count is still incremented by both threads. When AirDC started to
call this function simultaneously once per minute, it usually took a day
or so before users started to get extra hubs in their tags.

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https://bugs.launchpad.net/bugs/1194299

Title:
  Threading issues in hub management

Status in DC++:
  New

Bug description:
  AdcHub::info is called from various different threads (timer, refresh,
  hub, GUI) but it's not thread safe. lastInfoMap is unprotected while
  it can be modified from different threads simultaneously. This has
  been fixed in AirDC++ by syncing the info calls from other threads to
  the hub thread.

  Client::updateCounts is another function that shouldn't be called from
  different threads because the hub counts may go wrong. This started to
  cause real problems in AirDC++ when the info calls from TimerManager
  were synced to the hub threads, which caused them to get executed
  asynchronously all the time.

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