[Bug libgcj/20509] New: inline function _Jv_Select could return error code instead of throwing exception

["thebohemian at gmx dot net" <gcc-bugzilla@gcc.gnu.org>]

The function _Jv_Select from posix.cc contains the following fragment:

// Here we know we got EINTR.
      if (java::lang::Thread::interrupted ())
	throw new java::io::InterruptedIOException (JvNewStringLatin1 ("select
interrupted"));

A typical use of _Jv_Select is in natSelectorImplPosix.cc where the method
gnu::java::nio::VMSelector::select tests whether the InterruptedIOException has
been thrown like this:

// Actually do the select
   try
    {
      result = _Jv_select (max_fd + 1, &read_fds, &write_fds,
                           &except_fds, time_data);
    }
  catch (::java::io::InterruptedIOException *e)
    {
      ::java::lang::Thread::currentThread ()->interrupt ();
    }

However this could be implemented in a more efficient way by using a special
return code in _Jv_Select:
      if (java::lang::Thread::interrupted ())
	return SPECIAL;

and for gnu::java::nio::VMSelector::select:
      result = _Jv_select (max_fd + 1, &read_fds, &write_fds,
                           &except_fds, time_data);
      if(result == SPECIAL) {
      ::java::lang::Thread::currentThread ()->interrupt ();
      ...
      }
(the exception has to be swallowed for this method anyway!)

Other methods that use _Jv_Select may decide to throw the exception instead.

SPECIAL might be set to EINTR.

-- 
           Summary: inline function _Jv_Select could return error code
                    instead of throwing exception
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P2
         Component: libgcj
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: thebohemian at gmx dot net
                CC: gcc-bugs at gcc dot gnu dot org,java-prs at gcc dot gnu
                    dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20509