Implement restart in vcl_deliver(), and add test case for it.

Fixes: #411


git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@5644 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache_center.c

@@ -191,8 +191,18 @@ cnt_deliver(struct sess *sp)
 	case VCL_RET_DELIVER:
 		break;
 	case VCL_RET_RESTART:
-		INCOMPL();
-		break;
+		if (sp->restarts >= params->max_restarts)
+			break;
+		(void)HSH_Deref(sp->wrk, NULL, &sp->obj);
+		AZ(sp->obj);
+		sp->restarts++;
+		sp->director = NULL;
+		sp->wrk->bereq = NULL;
+		sp->wrk->beresp = NULL;
+		sp->wrk->beresp1 = NULL;
+		sp->wrk->resp = NULL;
+		sp->step = STP_RECV;
+		return (0);
 	default:
 		WRONG("Illegal action in vcl_deliver{}");
 	}

bin/varnishtest/tests/r00411.vtc

+# $Id$
+
+test "Test restart in vcl_deliver"
+
+server s1 {
+	rxreq
+	expect req.url == "/foo"
+	txresp -status 303 -hdr "Location: /bar"
+
+	rxreq
+	expect req.url == "/bar"
+	txresp -status 200 -body "1"
+} -start
+
+varnish v1 -vcl+backend { 
+	sub vcl_hit {
+		if (obj.http.X-Magic-Redirect == "1") {
+			set req.url = obj.http.Location;
+			return (restart);
+		}
+	}
+	sub vcl_fetch {
+		if (beresp.status == 303) {
+			set beresp.cacheable = true;
+			set beresp.http.X-Magic-Redirect = "1";
+		}
+	}
+	sub vcl_deliver {
+		if (resp.http.X-Magic-Redirect == "1") {
+			return (restart);
+		}
+		set resp.http.X-Restarts = req.restarts;
+	}
+} -start
+
+client c1 {
+	txreq -url "/foo"
+	rxresp
+	expect resp.status == 200
+	expect resp.bodylen == 1
+	expect resp.http.X-Restarts == "2"
+
+	txreq -url "/foo"
+	rxresp
+	expect resp.status == 200
+	expect resp.bodylen == 1
+	expect resp.http.X-Restarts == "1"
+} -run