You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@commons.apache.org by "Sebb (JIRA)" <ji...@apache.org> on 2012/10/05 20:02:03 UTC
[jira] [Resolved] (NET-466) Regression:
TelnetInputStream#available() blocks
[ https://issues.apache.org/jira/browse/NET-466?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Sebb resolved NET-466.
----------------------
Resolution: Fixed
> Regression: TelnetInputStream#available() blocks
> ------------------------------------------------
>
> Key: NET-466
> URL: https://issues.apache.org/jira/browse/NET-466
> Project: Commons Net
> Issue Type: Bug
> Components: Telnet
> Affects Versions: 3.1
> Reporter: Martin Oberhuber
> Priority: Critical
> Fix For: 3.2
>
>
> When testing with Commons Net 3.1 for Eclipse https://bugs.eclipse.org/bugs/show_bug.cgi?id=194473 , I found that our telnet client blocks when the ReaderThread is running and waiting for new data. Investigation shows that our code blocks on TelnetInputStream#available().
> This regression is due to the code introduced for NET-437 "TelnetInputStream doesn't support non-blocking IO when reader thread is not enabled":
> TelnetInputStream#available() now calls super.available() which is declared as "synchronized" on BufferedInputStream in JDK 1.6.0_21 at least. But at the same time, the telnet ReaderThread has already the Monitor on BufferedInputStream and doesn't give it up while sitting in read0().
> This seems to be exactly the situation that the comment before TelnetInputStream#close() warns about:
> // Cannot be synchronized. Will cause deadlock if run() is blocked
> // in read because BufferedInputStream read() is synchronized.
> This is a severe issue since it violates the specification and use of available().
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira