7164570: (fs) WatchService queues CREATE event but not DELETE event for very short lived files [sol11]

[Chris Hegarty]

Looks fine Alan, nice test!

Trivially, typo in test description:
   < "Test that are CREATE and DELETE evenets are paired for very short
      lived files"
   ---
   > "Test that our CREATE and DELETE events are paired for very short
      lived files" *OR* "Tests that CREATE..."

-Chris.

On 01/05/12 08:54, Alan Bateman wrote:
>
> I need a reviewer for a small fix to the WatchService implementation
> that we use on Solaris 11.
>
> If a file is created in a watched directory and is immediately removed
> or renamed out then one should expect to receive either zero or two
> events (two events = ENTRY_CREATE + ENTRY_DELETE, assuming that the
> directory is watched for both events). On Solaris 11 only then it's
> possible to receive an ENTRY_CREATE event without a corresponding
> ENTRY_DELETE event. This arises because the watch service implementation
> on this platform has to scan a directory when it gets a notification
> that the directory has changed. It's possible that the file is detected
> during the scan but the attempt to register it for events fails because
> it is deleted. The bug in the current code is that the ENTRY_CREATE
> event is queued when the file is detected but before we attempt to
> register it. There are two ways to fix this, we either don't post the
> ENTRY_CREATE event for this case, or we special case the ENOENT error
> and queue both an ENTRY_CREATE and ENTRY_DELETE event. I decided to go
> for the latter.
>
> The webrev with the change is here:
>
> http://cr.openjdk.java.net/~alanb/7164570/webrev/
>
> Thanks,
> Alan.