Add an option to disable building with XFS support

Right now, if you have the xfs development headers installed,
they will be picked up. Add an option to disable this behaviour.

Fixes #1878

diff --git a/configure.ac b/configure.ac
index 2d4c681..e432975 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -683,10 +683,26 @@ AC_CHECK_HEADERS([ \
   wordexp.h \
 ])
 
-AC_CHECK_HEADERS([xfs/xqm.h], [], [],
-[
-#define _GNU_SOURCE
-])
+# --enable-xfs {{{
+AC_ARG_ENABLE([xfs],
+  [AS_HELP_STRING([--enable-xfs], [xfs support in df plugin @<:@default=yes@:>@])],
+  [],
+  [enable_xfs="auto"]
+)
+
+if test "x$enable_xfs" != "xno"; then
+  AC_CHECK_HEADERS([xfs/xqm.h],
+    [],
+    [
+      if test "x$enable_xfs" = "xyes"; then
+        AC_MSG_ERROR([xfs/xqm.h not found])
+      fi
+    ],
+    [[#define _GNU_SOURCE]]
+  )
+fi
+
+# }}}
 
 # For the dns plugin
 AC_CHECK_HEADERS(arpa/nameser.h)