Refactor window-system configuration

This change streamlines the window system selection code in
configure.in and moves many common function declarations from
window-specific headers to frame.h.  It introduces a new TERM_HEADER
macro in config.h: we set this macro to the right header to use for
the window system for which we're compiling Emacs and have source
files include it indirectly.  This way, we don't have to teach every
file about every window system.

1 files changed, 3 insertions, 11 deletions

diff --git a/src/font.c b/src/font.c
index 5b9e4f1cfcf..cf9964f08f3 100644
--- a/src/font.c
+++ b/src/font.c
@@ -38,17 +38,9 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 #include "fontset.h"
 #include "font.h"
 
-#ifdef HAVE_X_WINDOWS
-#include "xterm.h"
-#endif /* HAVE_X_WINDOWS */
-
-#ifdef HAVE_NTGUI
-#include "w32term.h"
-#endif /* HAVE_NTGUI */
-
-#ifdef HAVE_NS
-#include "nsterm.h"
-#endif /* HAVE_NS */
+#ifdef HAVE_WINDOW_SYSTEM
+#include TERM_HEADER
+#endif /* HAVE_WINDOW_SYSTEM */
 
 Lisp_Object Qopentype;