libnftables: Store top_scope in struct nft_ctx

Allow for interactive sessions to make use of defines. Since parser is
initialized for each line, top scope defines didn't persist although
they are actually useful for stuff like:

| # nft -i
| define goodports = { 22, 23, 80, 443 }
| add rule inet t c tcp dport $goodports accept
| add rule inet t c tcp sport $goodports accept

While being at it, introduce scope_alloc() and scope_free().

Signed-off-by: Phil Sutter <phil@nwl.cc>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/nftables.h b/include/nftables.h
index 21553c6b..90d33196 100644
--- a/include/nftables.h
+++ b/include/nftables.h
@@ -104,6 +104,7 @@ struct nft_cache {
 
 struct mnl_socket;
 struct parser_state;
+struct scope;
 
 #define MAX_INCLUDE_DEPTH	16
 
@@ -119,6 +120,7 @@ struct nft_ctx {
 	uint32_t		flags;
 	struct parser_state	*state;
 	void			*scanner;
+	struct scope		*top_scope;
 	void			*json_root;
 	FILE			*f[MAX_INCLUDE_DEPTH];
 };