configure: improve check for wayland-scanner binary

The plugin doesn't need the wayland-scanner package to be built
or run, it only needs the wayland-scanner program during compile time.

When cross-compiling, build systems might not have the wayland-scanner
package for the target system as it is a developer's tool, while it should
still be possible to use wayland-scanner from the host system.

This patch fixes it by not requiring the wayland-scanner package but
just the binary itself.

Note that the check is done outside of the PKG_CHECK_MODULES
as it doesn't work inside of it.

https://bugzilla.gnome.org/show_bug.cgi?id=752688

diff --git a/configure.ac b/configure.ac
index c50647c..d167bd5 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -2150,14 +2150,20 @@ AG_GST_CHECK_FEATURE(DIRECTFB, [directfb], dfbvideosink , [
 
 dnl **** Wayland ****
 translit(dnm, m, l) AM_CONDITIONAL(USE_WAYLAND, true)
+AC_PATH_PROG([wayland_scanner], [wayland-scanner])
 AG_GST_CHECK_FEATURE(WAYLAND, [wayland sink], wayland , [
-  PKG_CHECK_MODULES(WAYLAND, wayland-client >= 1.4.0 wayland-scanner, [
-    HAVE_WAYLAND="yes" ], [ HAVE_WAYLAND="no"
+  PKG_CHECK_MODULES(WAYLAND, wayland-client >= 1.4.0, [
+    if test "x$wayland_scanner" != "x"; then
+      HAVE_WAYLAND="yes"
+    else
+      AC_MSG_RESULT([wayland-scanner is required to build the wayland plugin])
+      HAVE_WAYLAND="no"
+    fi
+    ],
+    [ HAVE_WAYLAND="no"
   ])
 ])
 
-AC_PATH_PROG([wayland_scanner], [wayland-scanner])
-
 dnl **** WebP ****
 translit(dnm, m, l) AM_CONDITIONAL(USE_WEBP, true)
 AG_GST_CHECK_FEATURE(WEBP, [WebP], webp , [