So you should re-open 8041746 and close it as a dup of 6967419.
I am approving 6967419 since it fixes an apparent problem.
There may be additional problems but these are still theoretical ..
-phil.
On 11/17/2015 01:11 AM, Jayathirth D V wrote:
Hi Phil,
Thanks for pointing to JDK-8041746 .
_My observations:_
I think with Andrew's test case we are able to identify the problem
submitter might have faced in JDK-6967419 . By deliberately throwing
exception at count 30000L we are trying to reproduce scenario of
possible IOException where client is closing the socket(probably
because of communication problem between client & server) and IDAT
chunk is being written. If we change count to any other number(like
10L) which relates to writing of data apart from IDAT chunk we don't
see any issue(no exception and cache is closed properly).
This might explain why submitter is seeing 7 out of 20 fail.
Also by using the test case we are able to see flushedPos going past
by 4 bytes to Pos when ios.close() is called as mentioned by submitter
in JDK-6967419. So catching the IOException and updating 'startPos'
value, will not result in IndexOutOfBoundsException and ios.close()
will be performed properly.
Please let us know your inputs.
Thanks,
Jay
*From:*Phil Race
*Sent:* Tuesday, November 17, 2015 3:22 AM
*To:* Jayathirth D V
*Cc:* Prasanta Sadhukhan; [email protected]
*Subject:* Re: Review request for JDK-6967419 :
IndexOutOfBoundsException when drawing PNGs
This one reads like it should be obvious but I find it less so ..
The unsatisfying part is that we do not seem to know what caused
the IOException in the customer case.
Andrew came up with a way to reproduce the symptoms but we really
don't know what caused the exception in the case of the submitter.
It does not seem likely he was 'deliberately' throwing an exception to
mess up his own application.
I just found this : https://bugs.openjdk.java.net/browse/JDK-8041746
The interesting part is that this bug (the one you are working on)
the submitter also wrote that he was using "a ServletOutputStream"
So consequently I wonder if it was something like what is described in
8041746 is going on here. It could explain how he sees 7 out of 20 fail.
Please take a look at that one to have a think about it.
Would your fix help that real world case ?
-phil.
On 11/12/2015 08:11 PM, Jayathirth D V wrote:
Hi Phil,
I have added public evaluation in bug. Please review.
Thanks,
Jay
*From:*Philip Race
*Sent:* Friday, November 13, 2015 12:11 AM
*To:* Jayathirth D V
*Cc:* Prasanta Sadhukhan; [email protected]
<mailto:[email protected]>
*Subject:* Re: Review request for JDK-6967419 :
IndexOutOfBoundsException when drawing PNGs
Please add a *public* evaluation to the bug report. I will look at
it more then ..
-phil.
On 11/6/15, 2:20 AM, Jayathirth D V wrote:
Hi Prasanta,
As discussed, only in case of write_IDAT there is finally
block which calls ios.finish() which internally calls seek()
with improper startPos. In other cases we are not trying to
access improper startPos because there is no call to
ios.finish(). We can verify this behavior by changing logic
where we throw IOException in test case.
And I have modified test to not catch IOBE as per your
suggestion. Please find updated Webrev link:
http://cr.openjdk.java.net/~rchamyal/jay/6967419/webrev.01/
<http://cr.openjdk.java.net/%7Erchamyal/jay/6967419/webrev.01/>
Thanks,
Jay
*From:*prasanta sadhukhan
*Sent:* Friday, November 06, 2015 2:45 PM
*To:* Jayathirth D V; [email protected]
<mailto:[email protected]>
*Cc:* Philip Race
*Subject:* Re: Review request for JDK-6967419 :
IndexOutOfBoundsException when drawing PNGs
Hi Jay,
looks ok but
I guess you need to do the same for finish() method too in
similar way you did for finishChunk() as finish() is called
from write_IHDR, write_CHRM etc and it calls flushBefore().
Also, I guess you should not consume IOB Exception and let it
be thrown to user instead of RuntimeException after catching IOBE.
Regards
Prasanta
On 11/5/2015 5:25 PM, Jayathirth D V wrote:
Hello All,
Please review following fix in jdk9:
Bug : https://bugs.openjdk.java.net/browse/JDK-6967419
Webrev :
http://cr.openjdk.java.net/~rchamyal/jay/6967419/webrev.00/
<http://cr.openjdk.java.net/%7Erchamyal/jay/6967419/webrev.00/>
Bug : IndexOutOfBoundsException when drawing PNGs
Root cause : When user intentionally throws IO Exception
while write is happening.
We call ios.finish() in finally
block of write_IDAT() which internally goes to
finishChunk(). But the startPos of the chunk is still
pointing to present IDAT chunk but flushedPos(streamPos)
is pointing to end of IDAT chunk.
So in finishChunk(), startPos
will be less than flushedPos. This is causing
IndexOutOfBoundException in stream.seek() and cache is not
closed.
Solution : If IOException is thrown by user, catch the
exception while write is happening and update startPos to
streamPos. So that when seek() happens in finishChunk() we
don't see IndexOutOfBoundsException and cache is closed
properly.
Thanks,
Jay
