peek_buffer
Description:
Parameters:
| this | 
           the pad to get buffer from  | 
      
Returns:
| 
           A reference to the buffer in this or NULL if no buffer was queued. You should unref the buffer after usage.  | 
      
| this | 
           the pad to get buffer from  | 
      
| 
           A reference to the buffer in this or NULL if no buffer was queued. You should unref the buffer after usage.  |