To each .c and .h file, add:
/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
'gnu' is the default anyways for Emacs, but indent-tabs-mode is not,
so this sets things up to correspond to the policy of no-tabs.
http://bugzilla.moblin.org/show_bug.cgi?id=6467