Fix a bug in setting *.ttl variables from VCL and go over

testcases at the same time.

Spotted by:	UPLEX

bin/varnishd/cache/cache_vrt_var.c

@@ -483,17 +483,23 @@ VRT_r_bereq_retries(const struct vrt_ctx *ctx)
 }
 
 /*--------------------------------------------------------------------
- * NB: TTL is relative to when object was created, whereas grace and
- * keep are relative to ttl.
+ * In exp.*:
+ *	t_origin is absolute
+ *	ttl is relative to t_origin
+ *	grace&keep are relative to ttl
+ * In VCL:
+ *	ttl is relative to now
+ *	grace&keep are relative to ttl
  */
 
-#define VRT_DO_EXP_L(which, sexp, fld)				\
+#define VRT_DO_EXP_L(which, sexp, fld, offset)			\
 								\
 void								\
 VRT_l_##which##_##fld(const struct vrt_ctx *ctx, double a)	\
 {								\
 								\
 	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);			\
+	a += (offset);						\
 	if (a < 0.0)						\
 		a = 0.0;					\
 	sexp.fld = a;						\
@@ -506,23 +512,28 @@ VRT_l_##which##_##fld(const struct vrt_ctx *ctx, double a)	\
 double								\
 VRT_r_##which##_##fld(const struct vrt_ctx *ctx)		\
 {								\
+	double d;						\
 								\
 	CHECK_OBJ_NOTNULL(ctx, VRT_CTX_MAGIC);			\
-	if (sexp.fld > 0.0)					\
-		return(sexp.fld - offset);			\
-	return(0.0);						\
+	d = sexp.fld;						\
+	if (d <= 0.0)						\
+		d = 0.0;					\
+	d -= (offset);						\
+	return(d);						\
 }
 
 VRT_DO_EXP_R(obj, ctx->req->objcore->exp, ttl,
-   (ctx->req->t_req - ctx->req->objcore->exp.t_origin))
+    ctx->now - ctx->req->objcore->exp.t_origin)
 VRT_DO_EXP_R(obj, ctx->req->objcore->exp, grace, 0)
 VRT_DO_EXP_R(obj, ctx->req->objcore->exp, keep, 0)
 
-VRT_DO_EXP_L(beresp, ctx->bo->fetch_objcore->exp, ttl)
-VRT_DO_EXP_R(beresp, ctx->bo->fetch_objcore->exp, ttl, 0)
-VRT_DO_EXP_L(beresp, ctx->bo->fetch_objcore->exp, grace)
+VRT_DO_EXP_L(beresp, ctx->bo->fetch_objcore->exp, ttl,
+    ctx->now - ctx->bo->fetch_objcore->exp.t_origin)
+VRT_DO_EXP_R(beresp, ctx->bo->fetch_objcore->exp, ttl,
+    ctx->now - ctx->bo->fetch_objcore->exp.t_origin)
+VRT_DO_EXP_L(beresp, ctx->bo->fetch_objcore->exp, grace, 0)
 VRT_DO_EXP_R(beresp, ctx->bo->fetch_objcore->exp, grace, 0)
-VRT_DO_EXP_L(beresp, ctx->bo->fetch_objcore->exp, keep)
+VRT_DO_EXP_L(beresp, ctx->bo->fetch_objcore->exp, keep, 0)
 VRT_DO_EXP_R(beresp, ctx->bo->fetch_objcore->exp, keep, 0)
 
 /*--------------------------------------------------------------------

bin/varnishtest/tests/c00060.vtc

@@ -11,6 +11,7 @@ server s1 {
 	txresp -status "304" \
 		-hdr "Last-Modified: Thu, 26 Jun 2008 12:00:01 GMT" \
 		-hdr "Snafu: 2" \
+		-hdr "Grifle: 3" \
 		-nolen
 
 } -start
@@ -40,6 +41,7 @@ client c1 {
 	rxresp
 	expect resp.bodylen == 13
 	expect resp.http.foobar == foo0
+	expect resp.http.grifle == 3
 	expect resp.http.snafu == 2a
 } -run
 

bin/varnishtest/tests/r00956.vtc

@@ -7,6 +7,7 @@ server s1 {
 
 varnish v1 -vcl+backend {
 	sub vcl_backend_response {
+		set beresp.http.fooA = beresp.ttl;
 		set beresp.ttl = 10s;
 		set beresp.http.fooB = beresp.ttl;
 	}
@@ -22,21 +23,22 @@ client c1 {
 	txreq
 	rxresp
 	expect resp.bodylen == 40
+	expect resp.http.fooA == 19.000
 	expect resp.http.fooB == 10.000
 
 	delay 2
 	txreq
 	rxresp
 	expect resp.bodylen == 40
-	# XXX: should be: < 8
+	expect resp.http.fooA == 19.000
 	expect resp.http.fooB == 10.000
-	expect resp.http.foo != 10.000
-	expect resp.http.foo != 9.000
+	expect resp.http.foo <= 8.000
 
 	delay 2
 	txreq
 	rxresp
 	expect resp.bodylen == 40
+	expect resp.http.fooA == 19.000
 	expect resp.http.fooB == 10.000
-	expect resp.http.foo <= 5.000
+	expect resp.http.foo <= 6.000
 } -run

bin/varnishtest/tests/r01578.vtc

@@ -21,7 +21,7 @@ client c1 {
 	txreq
 	rxresp
 	expect resp.bodylen == 40
-	expect resp.http.x-ttl == 23.000
+	expect resp.http.x-ttl == 19.000
 	expect resp.http.Age == 4
 
 
@@ -29,13 +29,13 @@ client c1 {
 	txreq
 	rxresp
 	expect resp.bodylen == 40
-	expect resp.http.x-ttl == 23.000
-	expect resp.http.x-remaining-ttl ~ ^17\.0|^16\.[89]
+	expect resp.http.x-ttl == 19.000
+	expect resp.http.x-remaining-ttl <= 17.000
 
 	delay 2
 	txreq
 	rxresp
 	expect resp.bodylen == 40
-	expect resp.http.x-ttl == 23.000
-	expect resp.http.x-remaining-ttl ~ ^15\.0|^14\.[89]
+	expect resp.http.x-ttl == 19.000
+	expect resp.http.x-remaining-ttl <= 15.000
 } -run