diff --git a/.jenkins.d/util.sh b/.jenkins.d/util.sh
new file mode 100644
index 0000000..a89bc27
--- /dev/null
+++ b/.jenkins.d/util.sh
@@ -0,0 +1,18 @@
+has() {
+    local saved_xtrace
+    [[ $- == *x* ]] && saved_xtrace=-x || saved_xtrace=+x
+    set +x
+
+    local p=$1
+    shift
+    local i ret=1
+    for i in "$@"; do
+        if [[ "${i}" == "${p}" ]]; then
+            ret=0
+            break
+        fi
+    done
+
+    set ${saved_xtrace}
+    return ${ret}
+}