Since we have already begun reworking the VCL type definitions, move

the goal-posts a serious distance while we're at it:

We can use the thread workspace for small temporary allocations during
VCL execution, use this to allocate a compound type for the HEADER
type, to get us closer to typedef-ability for VCL mapped types.

bin/varnishd/cache/cache_vrt.c

@@ -51,6 +51,22 @@
 
 const void * const vrt_magic_string_end = &vrt_magic_string_end;
 
+/*--------------------------------------------------------------------*/
+
+const struct gethdr_s *
+VRT_MkGethdr(struct req *req, enum gethdr_e where, const char *what)
+{
+	struct gethdr_s *retval;
+
+	CHECK_OBJ_NOTNULL(req, REQ_MAGIC);
+	retval = (void*)WS_Alloc(req->wrk->aws, sizeof *retval);
+	AN(retval);
+	retval->where = where;
+	retval->what = what;
+	return (retval);
+}
+
+
 /*--------------------------------------------------------------------*/
 
 void

include/vrt.h

@@ -38,6 +38,13 @@ struct director;
 struct VCL_conf;
 struct sockaddr_storage;
 
+enum gethdr_e { HDR_REQ, HDR_RESP, HDR_OBJ, HDR_BEREQ, HDR_BERESP };
+
+struct gethdr_s {
+	enum gethdr_e	where;
+	const char	*what;
+};
+
 /*
  * A backend probe specification
  */
@@ -158,7 +165,7 @@ int VRT_rewrite(const char *, const char *);
 void VRT_error(struct req *, unsigned, const char *);
 int VRT_switch_config(const char *);
 
-enum gethdr_e { HDR_REQ, HDR_RESP, HDR_OBJ, HDR_BEREQ, HDR_BERESP };
+const struct gethdr_s *VRT_MkGethdr(struct req *,enum gethdr_e, const char *);
 char *VRT_GetHdr(const struct req *, enum gethdr_e where, const char *);
 void VRT_SetHdr(struct req *, enum gethdr_e where, const char *,
     const char *, ...);

lib/libvcl/vcc_expr.c

@@ -605,7 +605,8 @@ vcc_Eval_Func(struct vcc *tl, struct expr **e, const struct symbol *sym)
 				vcc_ErrWhere(tl, tl->t);
 				return;
 			}
-			e1 = vcc_mk_expr(VOID, "%s, \"%s\"", v->http, v->hdr);
+			e1 = vcc_mk_expr(VOID, "VRT_MkGethdr(req, %s, \"%s\")",
+			    v->http, v->hdr);
 			if (*p != '\0')
 				SkipToken(tl, ',');
 		} else {

lib/libvcl/vmodtool.py

@@ -56,7 +56,7 @@ ctypes = {
 	'REAL':		"double",
 	'DURATION':	"double",
 	'INT':		"long",
-	'HEADER':	"enum gethdr_e, const char *",
+	'HEADER':	"const struct gethdr_s *",
 	'PRIV_VCL':	"struct vmod_priv *",
 	'PRIV_CALL':	"struct vmod_priv *",
 	'VOID':		"void",

lib/libvmod_std/vmod_std.c

@@ -169,12 +169,12 @@ vmod_syslog(struct req *req, long fac, const char *fmt, ...)
 }
 
 void __match_proto__(td_std_collect)
-vmod_collect(struct req *req, enum gethdr_e e, const char *h)
+vmod_collect(struct req *req, const struct gethdr_s *hdr)
 {
 
 	CHECK_OBJ_NOTNULL(req, REQ_MAGIC);
-	if (e == HDR_REQ)
-		http_CollectHdr(req->http, h);
-	else if (e == HDR_BERESP && req->busyobj != NULL)
-		http_CollectHdr(req->busyobj->beresp, h);
+	if (hdr->where == HDR_REQ)
+		http_CollectHdr(req->http, hdr->what);
+	else if (hdr->where == HDR_BERESP && req->busyobj != NULL)
+		http_CollectHdr(req->busyobj->beresp, hdr->what);
 }