Don't require xdmcp in configure.ac (#22583)

X.Org Bug 22583 <http://bugs.freedesktop.org/show_bug.cgi?id=22583

>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

configure.ac

@@ -54,9 +54,18 @@ AC_SUBST(XPROTO_CFLAGS)
 case "$ac_cv_use_xcb" in
 no)
 	X11_REQUIRES="xau xcmiscproto bigreqsproto"
-	X11_EXTRA_DEPS="xau xdmcp"
-	PKG_CHECK_MODULES(XDMCP, xdmcp)
-	AC_CHECK_LIB(Xdmcp, XdmcpWrap, [xdmauth="yes"], [xdmauth="no"], [$XDMCP_LIBS])
+	X11_EXTRA_DEPS="xau"
+	PKG_CHECK_MODULES(XDMCP, xdmcp,
+		AC_CHECK_LIB(Xdmcp, XdmcpWrap,
+			[
+			AC_CHECK_LIB(Xdmcp, XdmcpWrap, [xdmauth="yes"], [xdmauth="no"], [$XDMCP_LIBS])
+			X11_EXTRA_DEPS="$X11_EXTRA_DEPS xdmcp"
+			],
+			[
+			XDMCP_CFLAGS=
+			XDMCP_LIBS=
+			], [$XDMCP_LIBS]),
+		[AC_MSG_RESULT(no)])
 	AC_DEFINE(USE_XCB, 0, [Use XCB for low-level protocol implementation])
 	;;
 *)

src/ConnDis.c

@@ -39,7 +39,9 @@ in this Software without prior written authorization from The Open Group.
 #include <X11/Xlibint.h>
 #include <X11/Xtrans/Xtrans.h>
 #include <X11/Xauth.h>
+#ifdef HASXDMAUTH
 #include <X11/Xdmcp.h>
+#endif
 #include <stdio.h>
 #include <ctype.h>
 #include <unistd.h>