[PATCH xserver] configure: Xephyr, xfake and xfbdev require kdrive

[Olivier Fourdan]

Raise an error at configure time if one of the DDX that require kdrive
is enabled but kdrive itself is not.

That avoids the build to silently ignore Xephyr, Xfake and Xfbdev if
--enable-kdrive is not set as well.

Signed-off-by: Olivier Fourdan <ofourdan at redhat.com>
---
 configure.ac | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/configure.ac b/configure.ac
index e291b34..d6b8416 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2457,6 +2457,17 @@ if test "$KDRIVE" = yes; then
 
     AC_SUBST([XEPHYR_LIBS])
     AC_SUBST([XEPHYR_INCS])
+else
+    dnl Make sure none of the kdrive dependent servers are enabled if kdrive is not
+    if test "$XEPHYR" = yes; then
+        AC_MSG_ERROR([Xephyr requires kdrive.])
+    fi
+    if test "$XFAKE" = yes; then
+        AC_MSG_ERROR([fake server requires kdrive.])
+    fi
+    if test "$XFBDEV" = yes; then
+        AC_MSG_ERROR([framebuffer device server requires kdrive.])
+    fi
 fi
 AC_SUBST([KDRIVE_INCS])
 AC_SUBST([KDRIVE_PURE_INCS])
-- 
2.9.3