Mark objects with a "gziped" bit if they are.

bin/varnishd/cache.h

@@ -430,7 +430,9 @@ struct object {
 	double			ban_t;
 	unsigned		response;
 
+	/* XXX: make bitmap */
 	unsigned		cacheable;
+	unsigned		gziped;
 
 	ssize_t			len;
 

bin/varnishd/cache_center.c

@@ -179,8 +179,7 @@ cnt_deliver(struct sess *sp)
 		sp->wrk->res_mode |= RES_ESI_CHILD;
 	}
 
-	if (params->http_gzip_support &&
-	    http_HdrIs(sp->obj->http, H_Content_Encoding, "gzip") &&
+	if (params->http_gzip_support && sp->obj->gziped &&
 	    !RFC2616_Req_Gzip(sp)) {
 		/*
 		 * We don't know what it uncompresses to
@@ -662,6 +661,7 @@ cnt_fetch(struct sess *sp)
 	CHECK_OBJ_NOTNULL(sp->obj, OBJECT_MAGIC);
 
 	sp->wrk->storage_hint = NULL;
+	sp->obj->gziped = sp->wrk->is_gzip;
 
 	if (vary != NULL) {
 		sp->obj->vary =

bin/varnishd/cache_esi_fetch.c

@@ -269,6 +269,7 @@ vfp_esi_bytes_gg(struct sess *sp, struct http_conn *htc, size_t bytes)
 		do {
 			VGZ_Obuf(sp->wrk->vgz_rx, ibuf2, sizeof ibuf2);
 			i = VGZ_Gunzip(sp->wrk->vgz_rx, &dp, &dl);
+			/* XXX: check i */
 			vef->bufp = ibuf2;
 			if (dl > 0)
 				VEP_parse(sp, ibuf2, dl);
@@ -373,6 +374,9 @@ vfp_esi_end(struct sess *sp)
 		sp->wrk->vef_priv = NULL;
 		CHECK_OBJ_NOTNULL(vef, VEF_MAGIC);
 		XXXAZ(vef->error);
+		sp->obj->gziped = 1;
+	} else {
+		sp->obj->gziped = 0;
 	}
 	return (0);
 }

bin/varnishd/cache_gzip.c

@@ -383,6 +383,7 @@ vfp_gunzip_end(struct sess *sp)
 	vg = sp->wrk->vgz_rx;
 	CHECK_OBJ_NOTNULL(vg, VGZ_MAGIC);
 	VGZ_Destroy(&vg);
+	sp->obj->gziped = 0;
 	return (0);
 }
 
@@ -458,6 +459,7 @@ vfp_gzip_end(struct sess *sp)
 		sp->obj->len += dl;
 	} while (i != Z_STREAM_END);
 	VGZ_Destroy(&vg);
+	sp->obj->gziped = 1;
 	return (0);
 }