[PATCH nft 2/3] expr: add expr_ops_by_type()

[Pablo Neira Ayuso <pablo@netfilter.org>]

Fetch expression operation from the expression type.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/expression.h |  1 +
 src/expression.c     | 12 ++++++++++++
 2 files changed, 13 insertions(+)

diff --git a/include/expression.h b/include/expression.h
index 717b67550381..d502fc2a8611 100644
--- a/include/expression.h
+++ b/include/expression.h
@@ -169,6 +169,7 @@ struct expr_ops {
 };
 
 const struct expr_ops *expr_ops(const struct expr *e);
+const struct expr_ops *expr_ops_by_type(enum expr_types etype);
 
 /**
  * enum expr_flags
diff --git a/src/expression.c b/src/expression.c
index 6fa2f1dd9b12..a7bbde7eec1a 100644
--- a/src/expression.c
+++ b/src/expression.c
@@ -1222,3 +1222,15 @@ const struct expr_ops *expr_ops(const struct expr *e)
 
 	BUG("Unknown expression type %d\n", e->etype);
 }
+
+const struct expr_ops *expr_ops_by_type(enum expr_types etype)
+{
+	switch (etype) {
+	case EXPR_PAYLOAD:
+		return &payload_expr_ops;
+	default:
+		break;
+	}
+
+	BUG("Unknown expression type %d\n", etype);
+}
-- 
2.11.0