Merge stale-while-revalidate handling into RFC2616_Ttl

Log the grace period as part of the SLT_TTL VSL tag.

bin/varnishd/cache/cache.h

@@ -1085,7 +1085,6 @@ unsigned RFC2616_Req_Gzip(const struct http *);
 int RFC2616_Do_Cond(const struct req *sp);
 void RFC2616_Weaken_Etag(struct http *hp);
 void RFC2616_Vary_AE(struct http *hp);
-void RFC5861_Stale(const struct busyobj *);
 
 /* stevedore.c */
 int STV_NewObject(struct objcore *, struct worker *,

bin/varnishd/cache/cache_fetch.c

@@ -366,8 +366,6 @@ vbf_stp_startfetch(struct worker *wrk, struct busyobj *bo)
 	EXP_Clr(&bo->fetch_objcore->exp);
 	RFC2616_Ttl(bo, now);
 
-	RFC5861_Stale(bo);
-
 	/* private objects have negative TTL */
 	if (bo->fetch_objcore->flags & OC_F_PRIVATE)
 		bo->fetch_objcore->exp.ttl = -1.;

bin/varnishd/cache/cache_rfc2616.c

@@ -173,10 +173,22 @@ RFC2616_Ttl(struct busyobj *bo, double now)
 
 	}
 
-	/* calculated TTL, Our time, Date, Expires, max-age, age */
+	/*
+	 * RFC5861 outlines a way to control the use of stale responses.
+	 * We use this to initialize the grace period.
+	 */
+	if (expp->ttl >= 0 && http_GetHdrField(hp, H_Cache_Control,
+	    "stale-while-revalidate", &p) && p != NULL) {
+
+		if (*p == '-')
+			expp->grace = 0;
+		else
+			expp->grace = strtoul(p, NULL, 0);
+	}
+
 	VSLb(bo->vsl, SLT_TTL,
 	    "RFC %.0f %.0f %.0f %.0f %.0f %.0f %.0f %u",
-	    expp->ttl, -1., -1., now,
+	    expp->ttl, expp->grace, -1., now,
 	    expp->t_origin, h_date, h_expires, max_age);
 }
 
@@ -275,35 +287,3 @@ RFC2616_Vary_AE(struct http *hp)
 		http_SetHeader(hp, "Vary: Accept-Encoding");
 	}
 }
-
-/*
- * RFC5861 outlines a way to control the use of stale responses.
- * We use this to initialize the grace period.
- */
-
-void
-RFC5861_Stale(const struct busyobj *bo)
-{
-	const char *p;
-	const struct http *hp;
-	struct exp *expp;
-
-	expp = &bo->fetch_objcore->exp;
-
-	/*
-	 * If we are not meant to cache this ignore any potential
-	 * stale-while-revalidate values.
-	 */
-	if (expp->ttl < 0.)
-		return;
-
-	hp = bo->beresp;
-
-	if (http_GetHdrField(hp, H_Cache_Control,
-	    "stale-while-revalidate", &p) && p != NULL) {
-		if (*p == '-')
-			expp->grace = 0;
-		else
-			expp->grace = strtoul(p, NULL, 0);
-	}
-}

include/tbl/vsl_tags.h

@@ -211,7 +211,7 @@ SLTM(TTL, 0, "TTL set on object",
 	"\n"
 	"The last four fields are only present in \"RFC\" headers.\n\n"
 	"Examples::\n\n"
-	"\tRFC 60 -1 -1 1312966109 1312966109 1312966109 0 60\n"
+	"\tRFC 60 10 -1 1312966109 1312966109 1312966109 0 60\n"
 	"\tVCL 120 10 0 1312966111\n"
 	"\n"
 )