[sctp-dev] Socket Options Issue

[Alan Bateman]

Bruce Buffam wrote:
>
> Hi Chris,
>
>  
>
> I am currently working on integrating the use of SCTP channels into 
> Netty, an Open Source networking framework and I encountered an odd 
> behaviour in setting/getting SO_RCVBUF or SO_SNDBUF.  Typically, I 
> have some test code that sets one or both of these options and then 
> immediately tries to retrieve the value.  If the retrieved value does 
> not match the value that was set, the test code throws an exception.
>
FWIW, when you set these socket options then you are providing a "hint" 
so you can't assume that the retrieved value will always be exactly the 
value that you set.

>  
>
>  
>
> Here is some example code:
>
>  
>
>       @SuppressWarnings("restriction")
>
>       public void setReceiveBufferSize(int receiveBufferSize) {
>
>             // TODO Auto-generated method stub
>
>            
>
>             try {
>
>                   
> channel.setOption(SctpStandardSocketOption.SO_RCVBUF, receiveBufferSize);
>
>                   int temp = 
> channel.getOption(SctpStandardSocketOption.SO_RCVBUF);
>
>                   if (temp != receiveBufferSize)
>
>                         throw new IOException("SO_RCVBUF not correctly 
> set");
>
>             } catch (IOException e) {
>
>                   // TODO Auto-generated catch block
>
>                   e.printStackTrace();
>
>             }
>
>       }
>
>  
>
> My test case uses odd values like 9753, etc.  What I noticed, is that 
> when I do the get, it consistently retrieves the value I set, 
> multiplied by 2.
>
>
Chris - this sounds like you might be missing the conversion/mapping 
that is done by NET_SetSockOpt/NET_GetSocketOpt.

-Alan.