[ovs-dev] [cleanups 03/12] Add functions to determine how port should be opened based on type.

[Ben Pfaff]

On Fri, Nov 16, 2012 at 12:02:56AM -0800, Justin Pettit wrote:
> Depending on the port and type of datapath, a port may need to be opened
> as a different type of device than it's configured.  For example, an
> "internal" port on a "dummy" datapath should opened as a "dummy" port.
> This commit adds the ability for a dpif to provide this information to a
> caller.  It will be used in a future commit.
> 
> Signed-off-by: Justin Pettit <jpettit at nicira.com>

This looks good, with a few nits.

I think that the comments on the various incarnations of
"port_open_type" are likely to be very confusing to anyone new to the
code.  I recommend adding a little bit of background on why the type
might need to be translated and to give an example.

Also, the comment:
> +     * The caller must not free the returned string. */
is slightly confusing, because these functions are likely to return
their own arguments.  It might be better to say something like:

        Returns either 'type' itself or a string literal.

Or, possibly, that might be even more confusing.  Not sure.