cache: Support filtering for a specific flowtable

Extend nft_cache_filter to hold a flowtable name so 'list flowtable'
command causes fetching the requested flowtable only.

Dump flowtables just once instead of for each table, merely assign
fetched data to tables inside the loop.

Signed-off-by: Phil Sutter <phil@nwl.cc>

1 files changed, 10 insertions, 4 deletions

diff --git a/src/mnl.c b/src/mnl.c
index 47b3ca61..5413f865 100644
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -1826,11 +1826,13 @@ err_free:
 }
 
 struct nftnl_flowtable_list *
-mnl_nft_flowtable_dump(struct netlink_ctx *ctx, int family, const char *table)
+mnl_nft_flowtable_dump(struct netlink_ctx *ctx, int family,
+		       const char *table, const char *ft)
 {
 	struct nftnl_flowtable_list *nln_list;
 	char buf[MNL_SOCKET_BUFFER_SIZE];
 	struct nftnl_flowtable *n;
+	int flags = NLM_F_DUMP;
 	struct nlmsghdr *nlh;
 	int ret;
 
@@ -1838,10 +1840,14 @@ mnl_nft_flowtable_dump(struct netlink_ctx *ctx, int family, const char *table)
 	if (n == NULL)
 		memory_allocation_error();
 
-	nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETFLOWTABLE, family,
-				    NLM_F_DUMP, ctx->seqnum);
 	if (table != NULL)
 		nftnl_flowtable_set_str(n, NFTNL_FLOWTABLE_TABLE, table);
+	if (ft) {
+		nftnl_flowtable_set_str(n, NFTNL_FLOWTABLE_NAME, ft);
+		flags = NLM_F_ACK;
+	}
+	nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETFLOWTABLE, family,
+				    flags, ctx->seqnum);
 	nftnl_flowtable_nlmsg_build_payload(nlh, n);
 	nftnl_flowtable_free(n);
 
@@ -1850,7 +1856,7 @@ mnl_nft_flowtable_dump(struct netlink_ctx *ctx, int family, const char *table)
 		memory_allocation_error();
 
 	ret = nft_mnl_talk(ctx, nlh, nlh->nlmsg_len, flowtable_cb, nln_list);
-	if (ret < 0)
+	if (ret < 0 && errno != ENOENT)
 		goto err;
 
 	return nln_list;