handle NULL input

src/vmod_frozen.c

@@ -231,6 +231,10 @@ vmod_parser_parse(VRT_CTX, struct vmod_frozen_parser *vfpaa,
 	INIT_FROZEN_ARGS(args);
 	args->limit = vfpa->limit;
 
+	if (s == NULL) {
+		return (0);
+	}
+
 	if (vfpa->n_expect == 0)
 		return (!! json_walk_args(s, strlen(s), args));
 

src/vtc/vmod_frozen.vtc

@@ -28,6 +28,7 @@ varnish v1 -vcl+backend {
 	return (synth(200));
     }
     sub vcl_synth {
+	set resp.http.fail = p_test.parse(req.http.not);
 	set resp.http.parse =
 	  p_test.parse({"{ a: 1, b: "hi there", c: true, d: false, "} +
 	{" e : null, f: [ 1, -2, 3], g: { "1": [], h: [ 7 ] } } "});
@@ -70,6 +71,8 @@ client c1 {
 	txreq
 	rxresp
 	expect resp.status == 200
+	expect resp.http.fail == false
+	expect resp.http.parse == true
 	expect resp.http.a == 1
 	expect resp.http.a-type == NUMBER
 	expect resp.http.b == "hi there"