Function is_dvd_service

test/test.c:5768–5804

* is_dvd_service * * Returns whether or not the service passed in is a DVD. * * Searches for an IOMedia object that represents the entire (whole) media that * the volume is on. If the volume is on partitioned media, the whole media * object will be a parent of the volume's media object. If the media is not * partitioned, the volume's media object will be the whole media object. ***********

 * partitioned, the volume's media object will be the whole media object.
 ****************************************************************************/
static int is_dvd_service( io_service_t service )
{
    kern_return_t  kernResult;
    io_iterator_t  iter;

    // Create an iterator across all parents of the service object passed in.
    kernResult = IORegistryEntryCreateIterator( service,
                                                kIOServicePlane,
                                                kIORegistryIterateRecursively | kIORegistryIterateParents,
                                                &iter );
    if( kernResult != KERN_SUCCESS )
    {
        return 0;
    }
    if( iter == IO_OBJECT_NULL )
    {
        return 0;
    }

    // A reference on the initial service object is released in the do-while
    // loop below, so add a reference to balance.
    IOObjectRetain( service );

    int result = 0;
    do
    {
        if( is_whole_media_service( service ) &&
            IOObjectConformsTo( service, kIODVDMediaClass) )
        {
            result = 1;
        }
        IOObjectRelease( service );
    } while( !result && (service = IOIteratorNext( iter )) );
    IOObjectRelease( iter );

    return result;
}

/****************************************************************************
 * is_whole_media_service