Use pdiff()

git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@2209 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache_vrt_esi.c

@@ -319,8 +319,8 @@ esi_addinclude(struct esi_work *ew, txt t)
 
 			u = WS_Reserve(ws, 0);
 			v = snprintf(ws->f, u - 1, "%.*s%.*s",
-			    tag.e - tag.b, tag.b,
-			    val.e - val.b, val.b);
+			    pdiff(tag.b, tag.e), tag.b,
+			    pdiff(val.b, val.e), val.b);
 			v++;
 			xxxassert(v < u);
 			eb->include.b = ws->f;