configure.ac: complain when asciidoc cannot be found

related to #338

diff --git a/configure.ac b/configure.ac
index 9657e3f9e3a2ede6e40dd0b3ee44615b755f3806..c96a5bd9adafc53ecc52027b2fed20baa90ea532 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -101,7 +101,9 @@ AC_PROG_MAKE_SET
 AC_PROG_RANLIB
 AC_PROG_LN_S
 
-AC_PATH_PROG([PATH_ASCIIDOC], [asciidoc])
+AC_PATH_PROG([PATH_ASCIIDOC], [asciidoc], [no])
+AS_IF([test x"$PATH_ASCIIDOC" = x"no"],
+      [AC_MSG_ERROR([asciidoc is required for generating man pages])])
 AC_PATH_PROG([PATH_XMLTO], [xmlto], [no])
 AS_IF([test x"$PATH_XMLTO" = x"no"],
       [AC_MSG_ERROR([xmlto is required for generating man pages])])