Define ddxBeforeReset stubs in platform-neutral DDXs

XWin uses ddxBeforeReset, which is called in DIX.  Other DDXs need to
define these in order to avoid an undefined symbol error at link time
when building alongside XWin.  Xnest and Xvfb already provide empty stubs;
this does the same for Xdmx and the platform-neutral KDrive servers.

Also add a prototype to avoid a warning in all DDXs.

Signed-off-by: Yaakov Selkowitz <yselkowitz@users.sourceforge.net>
Signed-off-by: Keith Packard <keithp@keithp.com>

hw/dmx/dmxinit.c

@@ -846,6 +846,12 @@ void AbortDDX(void)
     }
 }
 
+#ifdef DDXBEFORERESET
+void ddxBeforeReset(void)
+{
+}
+#endif
+
 /** This function is called in Xserver/dix/main.c from \a main() when
  * dispatchException & DE_TERMINATE (which is the only way to exit the
  * main loop without an interruption. */

hw/kdrive/ephyr/ephyrinit.c

@@ -93,6 +93,13 @@ InitInput (int argc, char **argv)
   KdInitInput();
 }
 
+#ifdef DDXBEFORERESET
+void
+ddxBeforeReset (void)
+{
+}
+#endif
+
 void
 ddxUseMsg (void)
 {

hw/kdrive/fake/fakeinit.c

@@ -60,6 +60,13 @@ InitInput (int argc, char **argv)
     KdInitInput ();
 }
 
+#ifdef DDXBEFORERESET
+void
+ddxBeforeReset (void)
+{
+}
+#endif
+
 void
 ddxUseMsg (void)
 {

hw/kdrive/sdl/sdl.c

@@ -240,6 +240,12 @@ void InitInput(int argc, char **argv)
         KdInitInput();
 }
 
+#ifdef DDXBEFORERESET
+void ddxBeforeReset(void)
+{
+}
+#endif
+
 void ddxUseMsg(void)
 {
 	KdUseMsg();

include/os.h

@@ -83,6 +83,10 @@ typedef struct _NewClientRec *NewClientPtr;
 #include <stdio.h>
 #include <stdarg.h>
 
+#ifdef DDXBEFORERESET
+extern void ddxBeforeReset (void);
+#endif
+
 #ifdef DDXOSVERRORF
 extern _X_EXPORT void (*OsVendorVErrorFProc)(const char *, va_list args);
 #endif