Subject: [PATCH iproute2-next 1/5] libnetlink: Add filter function to rtnl_neighdump_req

From: David Ahern <[email-masked]>
Date: Wed, 2 Jan 2019 20:38:28 -0800

From: David Ahern <[email-masked]>

Add filter function to rtnl_neighdump_req and a buffer to the
request for the filter functions to append attributes.

Signed-off-by: David Ahern <[email-masked]>
---
 include/libnetlink.h |  3 ++-
 lib/libnetlink.c     | 12 +++++++++++-
 misc/arpd.c          |  2 +-
 3 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/include/libnetlink.h b/include/libnetlink.h
index dc0c9c4eb3f5..148951510d1e 100644
--- a/include/libnetlink.h
+++ b/include/libnetlink.h
@@ -60,7 +60,8 @@ int rtnl_routedump_req(struct rtnl_handle *rth, int family,
 	__attribute__((warn_unused_result));
 int rtnl_ruledump_req(struct rtnl_handle *rth, int family)
 	__attribute__((warn_unused_result));
-int rtnl_neighdump_req(struct rtnl_handle *rth, int family)
+int rtnl_neighdump_req(struct rtnl_handle *rth, int family,
+		       req_filter_fn_t filter_fn)
 	__attribute__((warn_unused_result));
 int rtnl_neightbldump_req(struct rtnl_handle *rth, int family)
 	__attribute__((warn_unused_result));
diff --git a/lib/libnetlink.c b/lib/libnetlink.c
index 4d7d081054fd..19318b445266 100644
--- a/lib/libnetlink.c
+++ b/lib/libnetlink.c
@@ -327,11 +327,13 @@ int rtnl_ruledump_req(struct rtnl_handle *rth, int family)
 	return send(rth->fd, &req, sizeof(req), 0);
 }
 
-int rtnl_neighdump_req(struct rtnl_handle *rth, int family)
+int rtnl_neighdump_req(struct rtnl_handle *rth, int family,
+		       req_filter_fn_t filter_fn)
 {
 	struct {
 		struct nlmsghdr nlh;
 		struct ndmsg ndm;
+		char buf[256];
 	} req = {
 		.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
 		.nlh.nlmsg_type = RTM_GETNEIGH,
@@ -340,6 +342,14 @@ int rtnl_neighdump_req(struct rtnl_handle *rth, int family)
 		.ndm.ndm_family = family,
 	};
 
+	if (filter_fn) {
+		int err;
+
+		err = filter_fn(&req.nlh, sizeof(req));
+		if (err)
+			return err;
+	}
+
 	return send(rth->fd, &req, sizeof(req), 0);
 }
 
diff --git a/misc/arpd.c b/misc/arpd.c
index ce7c09978c2b..504961cb5e3a 100644
--- a/misc/arpd.c
+++ b/misc/arpd.c
@@ -424,7 +424,7 @@ static int do_one_request(struct nlmsghdr *n)
 
 static void load_initial_table(void)
 {
-	if (rtnl_neighdump_req(&rth, AF_INET) < 0) {
+	if (rtnl_neighdump_req(&rth, AF_INET, NULL) < 0) {
 		perror("dump request failed");
 		exit(1);
 	}
-- 
2.11.0