RFR: 8189366: SocketInputStream.available() should check for eof

[Daniel Fuchs]

On 12/10/2018 12:01, Chris Hegarty wrote:
> That buys us little more than we had prior to this change,
> since impl.available will still call into native before
> checking the EOF status.
> 
> If we want to keep this, then we need:
> 
>      public int available() throws IOException {
>          if (impl.isClosedOrPending()) {
>              throw new SocketException("Socket closed");
>          }
> 
>          if (eof) {
>              return 0;
>          } else {
>              return impl.available();
>          }
>      }
> 

Hmmm...

I thought impl.available() was going to throw the
exception?

If you don't want to penalize the regular case  where
eof is false, and the impl is supposed to throw the
exception, and you want to avoid to go back to the
native impl when eof has been reached, then maybe you
need:

     public int available() throws IOException {
         if (eof) {
             if (impl.isClosedOrPending()) {
                 throw new SocketException("Socket closed");
             }
             return 0;
         } else {
             return impl.available();
         }
     }

and that's assuming the that the exception that the impl would
throw is exactly new SocketException("Socket closed");

Can't help feeling that

     int available = impl.available();
     return eof ? 0 : available;

addresses the issue of available potentially returning garbage
after EOF while being much less risky...

cheers,

-- daniel