proto: add support for meta templates

The following two patches will add two new meta expression types that are
used as dependencies in the inet table. To reuse the existing dependency
generation code, add a slightly hackish way to specify meta expressions
as payload dependencies.

Signed-off-by: Patrick McHardy <kaber@trash.net>

1 files changed, 5 insertions, 1 deletions

diff --git a/src/payload.c b/src/payload.c
index 0ef3c791..04a3455e 100644
--- a/src/payload.c
+++ b/src/payload.c
@@ -187,7 +187,11 @@ int payload_gen_dependency(struct eval_ctx *ctx, const struct expr *expr,
 				  desc->name, expr->payload.desc->name);
 
 	tmpl = &desc->templates[desc->protocol_key];
-	left = payload_expr_alloc(&expr->location, desc, desc->protocol_key);
+	if (tmpl->meta_key)
+		left = meta_expr_alloc(&expr->location, tmpl->meta_key);
+	else
+		left = payload_expr_alloc(&expr->location, desc, desc->protocol_key);
+
 	right = constant_expr_alloc(&expr->location, tmpl->dtype,
 				    BYTEORDER_HOST_ENDIAN,
 				    tmpl->len, &protocol);