+# Check for the XSHM server extension header.
+#
+have_xshm=no
+with_xshm_req=unspecified
+AC_ARG_WITH(xshm-ext,
+[ --with-xshm-ext Include support for the XSHM (Shared Memory) server
+ extension, if possible (this is the default).
+ --without-xshm-ext Do not compile in support for this extension.],
+ [with_xshm="$withval"; with_xshm_req="$withval"],[with_xshm=yes])
+
+HANDLE_X_PATH_ARG(with_xshm, --with-xshm-ext, XSHM)
+
+if test "$with_xshm" = yes; then
+
+ # first check for Xshm.h.
+ AC_CHECK_X_HEADER(X11/extensions/XShm.h, [have_xshm=yes])
+
+ # if that succeeded, then check for sys/ipc.h.
+ if test "$have_xshm" = yes; then
+ have_xshm=no
+ AC_CHECK_X_HEADER(sys/ipc.h, [have_xshm=yes])
+ fi
+
+ # if that succeeded, then check for sys/shm.h.
+ if test "$have_xshm" = yes; then
+ have_xshm=no
+ AC_CHECK_X_HEADER(sys/shm.h, [have_xshm=yes])
+ fi
+
+ # AIX is pathological, as usual: apparently it's normal for the Xshm headers
+ # to exist, but the library code to not exist. And even better, the library
+ # code is in its own library: libXextSam.a. So, if we're on AIX, and that
+ # lib doesn't exist, give up.
+ #
+ case "$host" in
+ *-aix*)
+ have_xshm=no
+ AC_CHECK_X_LIB(XextSam, XShmQueryExtension,
+ [have_xshm=yes; SAVER_LIBS="$SAVER_LIBS -lXextSam"],
+ [], -lX11 -lXext -lm)
+ ;;
+ esac
+
+ # if that succeeded, then we've really got it.
+ if test "$have_xshm" = yes; then
+ AC_DEFINE(HAVE_XSHM_EXTENSION)
+ fi
+
+elif test "$with_xshm" != no; then
+ echo "error: must be yes or no: --with-xshm-ext=$with_xshm"
+ exit 1
+fi
+
+
+# Check for the SGI-VIDEO-CONTROL server extension header.
+#
+have_sgivc=no
+with_sgivc_req=unspecified
+AC_ARG_WITH(sgivc-ext,
+[ --with-sgivc-ext Include support for the SGI-VIDEO-CONTROL server
+ extension, if possible (this is the default).
+ --without-sgivc-ext Do not compile in support for this extension.],
+ [with_sgivc="$withval"; with_sgivc_req="$withval"],[with_sgivc=yes])
+
+HANDLE_X_PATH_ARG(with_sgivc, --with-sgivc-ext, SGI-VIDEO-CONTROL)
+
+if test "$with_sgivc" = yes; then
+
+ # first check for XSGIvc.h
+ AC_CHECK_X_HEADER(X11/extensions/XSGIvc.h, [have_sgivc=yes])
+
+ # if that succeeded, then check for the -lXsgivc
+ if test "$have_sgivc" = yes; then
+ have_sgivc=no
+ AC_CHECK_X_LIB(Xsgivc, XSGIvcQueryGammaMap,
+ [have_sgivc=yes; SAVER_LIBS="$SAVER_LIBS -lXsgivc"], [],
+ -lXext -lX11)
+ fi
+
+ # if that succeeded, then we've really got it.
+ if test "$have_sgivc" = yes; then
+ AC_DEFINE(HAVE_SGI_VC_EXTENSION)
+ fi
+
+elif test "$with_sgivc" != no; then
+ echo "error: must be yes or no: --with-sgivc-ext=$with_sgivc"
+ exit 1
+fi
+
+
+# Check for the DPMS server extension header.
+#
+have_dpms=no
+with_dpms_req=unspecified
+AC_ARG_WITH(dpms-ext,
+[ --with-dpms-ext Include support for the DPMS server extension,
+ if possible (this is the default).
+ --without-dpms-ext Do not compile in support for this extension.],
+ [with_dpms="$withval"; with_dpms_req="$withval"],[with_dpms=yes])
+
+HANDLE_X_PATH_ARG(with_dpms, --with-dpms-ext, DPMS)
+
+if test "$with_dpms" = yes; then
+
+ # first check for dpms.h
+ AC_CHECK_X_HEADER(X11/extensions/dpms.h, [have_dpms=yes])
+
+ # if that succeeded, then check for the -lXdpms
+ if test "$have_dpms" = yes; then
+ have_dpms=no
+ AC_CHECK_X_LIB(Xdpms, DPMSInfo,
+ [have_dpms=yes; SAVER_LIBS="$SAVER_LIBS -lXdpms"], [],
+ -lXext -lX11)
+ fi
+
+ # if that succeeded, then we've really got it.
+ if test "$have_dpms" = yes; then
+ AC_DEFINE(HAVE_DPMS_EXTENSION)
+ fi
+
+elif test "$with_dpms" != no; then
+ echo "error: must be yes or no: --with-dpms-ext=$with_dpms"
+ exit 1
+fi
+
+
+