add test b00027.vtc

src/tests/b00027.vtc

+varnishtest "test backend transmission corner cases"
+
+server s1 {
+	rxreq
+	txresp
+	rxreq
+	txresp -proto HTTP/1.0 -hdr "Connection: keep-alive"
+	rxreq
+	send "HTTP/1.1 200 OK\n"
+	send "Transfer-encoding: foobar\n"
+	send "\n"
+} -start
+
+varnish v1 -vcl {
+	import backend_dyn from "${vmod_topbuild}/src/.libs/libvmod_backend_dyn.so";
+
+	backend dummy { .host="${bad_ip}"; }
+
+	sub vcl_init {
+		if (!backend_dyn.create(name="be", host="${s1_addr}",
+		   		        port="${s1_port}",
+					first_byte_timeout = 2s)) {
+			return(fail);
+		}
+	}
+
+	sub vcl_recv {
+		set req.backend_hint = backend_dyn.by_name("be");
+	}
+
+	sub vcl_backend_response {
+		set beresp.do_stream = false;
+	}
+} -start
+
+client c1 {
+	txreq -url /foo
+	rxresp
+	expect resp.status == 200
+	expect resp.bodylen == 0
+	txreq -url /bar
+	rxresp
+	expect resp.status == 200
+	expect resp.bodylen == 0
+	txreq -url /barf
+	rxresp
+	expect resp.status == 503
+} -run