config: Don't attempt to use D-Bus when not strictly necessary

If we have D-Bus but have explicitly disabled it, don't build it.

config/Makefile.am

@@ -3,7 +3,7 @@ AM_CFLAGS = @DIX_CFLAGS@
 noinst_LIBRARIES = libconfig.a
 libconfig_a_SOURCES = config.c config-backends.h
 
-if HAVE_DBUS
+if CONFIG_NEED_DBUS
 AM_CFLAGS += @DBUS_CFLAGS@
 libconfig_a_SOURCES += dbus-core.c
 endif

config/config-backends.h

@@ -27,7 +27,7 @@
 #include <dix-config.h>
 #endif
 
-#ifdef HAVE_DBUS
+#ifdef CONFIG_NEED_DBUS
 #include <dbus/dbus.h>
 
 typedef void (*config_dbus_core_connect_hook)(DBusConnection *connection,

configure.ac

@@ -706,7 +706,7 @@ if test "x$CONFIG_DBUS_API" = xyes; then
 	fi
 
 	AC_DEFINE(CONFIG_DBUS_API, 1, [Use the D-Bus input configuration API])
-	NEED_DBUS="yes"
+	CONFIG_NEED_DBUS="yes"
 fi
 AM_CONDITIONAL(CONFIG_DBUS_API, [test "x$CONFIG_DBUS_API" = xyes])
 
@@ -721,13 +721,15 @@ if test "x$CONFIG_HAL" = xyes; then
 
 	AC_DEFINE(CONFIG_HAL, 1, [Use the HAL hotplug API])
         REQUIRED_LIBS="$REQUIRED_LIBS hal"
-	NEED_DBUS="yes"
+	CONFIG_NEED_DBUS="yes"
 fi
 AM_CONDITIONAL(CONFIG_HAL, [test "x$CONFIG_HAL" = xyes])
 
-if test "x$NEED_DBUS" = xyes; then
+if test "x$CONFIG_NEED_DBUS" = xyes; then
 	REQUIRED_LIBS="$REQUIRED_LIBS dbus-1"
+        AC_DEFINE(CONFIG_NEED_DBUS, 1, [Use D-Bus for input hotplug])
 fi
+AM_CONDITIONAL(CONFIG_NEED_DBUS, [test "x$CONFIG_NEED_DBUS" = xyes])
 CONFIG_LIB='$(top_builddir)/config/libconfig.a'
 
 AC_MSG_CHECKING([for glibc...])

include/dix-config.h.in

@@ -468,6 +468,9 @@
 /* Support D-Bus */
 #undef HAVE_DBUS
 
+/* Use D-Bus for input hotplug */
+#undef CONFIG_NEED_DBUS
+
 /* Support the D-Bus hotplug API */
 #undef CONFIG_DBUS_API