Code Review Request : 7011591 JDWP socket transport should restart interrupted system calls (EINTR)

[David Buck]

Hi!

I would like to request that my fix for 7011591 be reviewed for push 
into JDK8 (and JDK7u if possible).

CR: 7011591 JDWP socket transport should restart interrupted system 
calls (EINTR)

Weblink: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=2205030
(for some reason, the public URL for the parent bug is not working. (I 
believe that SubCR 2205030 will have all needed information.)

Webrev: http://cr.openjdk.java.net/~dbuck/7011591/webrev.00/

Description:
Syscalls that can be interrupted by signal handling should automatically 
retry if they fail with EINTR. Unfortunately, the JDWP socket transport 
implementation does not do this. Since HotSpot does not use signals for 
thread suspension, HotSpot customers have not run into any problem (as 
far as I know). But because JRockit R27 and earlier releases use signals 
to suspend threads, all threads are constantly being interrupted thus 
JRockit customers are much more likely (almost guaranteed under some 
circumstances) to have system calls interrupted by signal handling.

I have added a loop to automatically retry send(), recv(), sendto(), 
recvfrom(), accept(), and poll() calls if the call fails with EINTR. 
Note that I do not believe that the UDP versions of the calls 
(recvfrom() and sendto()) are actualy ever used in the JDK, but I fixed 
them in case they are used in the future.

The implementation for connect() was more complicated because Solaris 
does not let us just call connect() again after EINTR. Once a call to 
connect() fails with EINTR on Solaris, the connection setup continues 
asynchronously and we need to use select() or poll() to determine when 
the socket can be used.

The patch for jdk7u2 is identical to this (jdk8) fix, if possible, I 
would like to receive pre-approval to push to jdk7u-dev repository as well.

This fix has already been done for 1.4.2/5/6 as part of the JRockit 
Simplification Project. This needs to be forward ported into 7 and 8 to 
avoid a regression.

Best Regards,
-Buck