[PATCH nft v2 04/11] src: parser: add syntax to provide size of variable-sized data types

[Florian Westphal <fw@xxxxxxxxx>]

This allows creation of sets with string and integer types by
providing the datatype width using a comma, e.g.

"type string, 64" or "integer, 32".

This is mainly intended as a fallback for the upcoming "typeof"
keyword -- if we can't make sense of the kernel provided type
(or its missing entirely), we can then fallback to this format.

Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
 src/parser_bison.y | 18 ++++++++++++++++++
 src/rule.c         | 24 +++++++++++++++++++-----
 2 files changed, 37 insertions(+), 5 deletions(-)

diff --git a/src/parser_bison.y b/src/parser_bison.y
index 6d17539fa57e..c6cad19f52fb 100644
--- a/src/parser_bison.y
+++ b/src/parser_bison.y
@@ -1891,6 +1891,24 @@ data_type_atom_expr	:	type_identifier
 				$$ = constant_expr_alloc(&@1, &time_type, time_type.byteorder,
 							 time_type.size, NULL);
 			}
+			|	type_identifier	COMMA	NUM
+			{
+				const struct datatype *dtype = datatype_lookup_byname($1);
+				if (dtype == NULL) {
+					erec_queue(error(&@1, "unknown datatype %s", $1),
+						   state->msgs);
+					YYERROR;
+				}
+
+				if (dtype->size) {
+					erec_queue(error(&@1, "Datatype %s has a fixed type", $1),
+						   state->msgs);
+					YYERROR;
+				}
+				$$ = constant_expr_alloc(&@1, dtype, dtype->byteorder,
+							 $3, NULL);
+				xfree($1);
+			}
 			;
 
 data_type_expr		:	data_type_atom_expr
diff --git a/src/rule.c b/src/rule.c
index f8cd4a73054b..a94860865f31 100644
--- a/src/rule.c
+++ b/src/rule.c
@@ -438,6 +438,16 @@ const char *set_policy2str(uint32_t policy)
 	}
 }
 
+static void set_print_key(const struct expr *expr, struct output_ctx *octx)
+{
+	const struct datatype *dtype = expr->dtype;
+
+	if (dtype->size || dtype->type == TYPE_VERDICT)
+		nft_print(octx, "%s", dtype->name);
+	else
+		nft_print(octx, "%s,%d", dtype->name, expr->len);
+}
+
 static void set_print_declaration(const struct set *set,
 				  struct print_fmt_options *opts,
 				  struct output_ctx *octx)
@@ -466,12 +476,16 @@ static void set_print_declaration(const struct set *set,
 	if (nft_output_handle(octx))
 		nft_print(octx, " # handle %" PRIu64, set->handle.handle.id);
 	nft_print(octx, "%s", opts->nl);
-	nft_print(octx, "%s%stype %s",
-		  opts->tab, opts->tab, set->key->dtype->name);
-	if (set_is_datamap(set->flags))
-		nft_print(octx, " : %s", set->data->dtype->name);
-	else if (set_is_objmap(set->flags))
+	nft_print(octx, "%s%stype ",
+		  opts->tab, opts->tab);
+	set_print_key(set->key, octx);
+
+	if (set_is_datamap(set->flags)) {
+		nft_print(octx, " : ");
+		set_print_key(set->data, octx);
+	} else if (set_is_objmap(set->flags)) {
 		nft_print(octx, " : %s", obj_type_name(set->objtype));
+	}
 
 	nft_print(octx, "%s", opts->stmt_separator);
 
-- 
2.23.0