Check if ragel is missing but needed and fail

diff --git a/configure.ac b/configure.ac
index c5c8ace5ebe9182b8d8c6085631765e94bee5312..342e2398b71c4bf50db11d6bb6d7f790272cbf56 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -56,7 +56,7 @@ eval full_libdir="\"$libdir\""
 # detect pkg-config explicitly
 PKG_PROG_PKG_CONFIG
 
-AC_CHECK_PROG([RAGEL], [ragel], [ragel])
+PDNS_CHECK_RAGEL
 AC_CHECK_PROG([ASCIIDOC], [asciidoc], [asciidoc])
 
 PDNS_WITH_LUA

diff --git a/m4/pdns_check_ragel.m4 b/m4/pdns_check_ragel.m4
new file mode 100644 (file)
index 0000000..9a49823
--- /dev/null
+++ b/m4/pdns_check_ragel.m4
@@ -0,0 +1,8 @@
+AC_DEFUN([PDNS_CHECK_RAGEL], [
+  AC_CHECK_PROG([RAGEL], [ragel], [ragel])
+  if test "x$RAGEL" = "x"; then
+    if test ! -f "${srcdir}/pdns/dnslabeltext.cc"; then
+      AC_MSG_ERROR([ragel is missing and you don't have ${srcdir}/pdns/dnslabeltext.cc. Install ragel or download sources from www.powerdns.com])
+    fi
+  fi
+])