[iproute2-next 2/2] tipc: add link broadcast get

[Hoang Le <hoang.h.le@dektech.com.au>]

The command prints the actually method that multicast
is running in the system.
Also 'ratio' value for AUTOSELECT method.

A sample usage is shown below:
$tipc link get broadcast
BROADCAST

$tipc link get broadcast
AUTOSELECT ratio:30%

$tipc link get broadcast -j -p
[ {
        "method": "AUTOSELECT"
    },{
        "ratio": 30
    } ]

Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
---
 tipc/link.c | 85 ++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 84 insertions(+), 1 deletion(-)

diff --git a/tipc/link.c b/tipc/link.c
index e3b10bb7b3d4..e123c1863575 100644
--- a/tipc/link.c
+++ b/tipc/link.c
@@ -175,10 +175,92 @@ static void cmd_link_get_help(struct cmdl *cmdl)
 		"PROPERTIES\n"
 		" tolerance             - Get link tolerance\n"
 		" priority              - Get link priority\n"
-		" window                - Get link window\n",
+		" window                - Get link window\n"
+		" broadcast             - Get link broadcast\n",
 		cmdl->argv[0]);
 }
 
+static int cmd_link_get_bcast_cb(const struct nlmsghdr *nlh, void *data)
+{
+	int *prop = data;
+	int prop_ratio = TIPC_NLA_PROP_BROADCAST_RATIO;
+	struct genlmsghdr *genl = mnl_nlmsg_get_payload(nlh);
+	struct nlattr *info[TIPC_NLA_MAX + 1] = {};
+	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1] = {};
+	struct nlattr *props[TIPC_NLA_PROP_MAX + 1] = {};
+	int bc_mode;
+
+	mnl_attr_parse(nlh, sizeof(*genl), parse_attrs, info);
+	if (!info[TIPC_NLA_LINK])
+		return MNL_CB_ERROR;
+
+	mnl_attr_parse_nested(info[TIPC_NLA_LINK], parse_attrs, attrs);
+	if (!attrs[TIPC_NLA_LINK_PROP])
+		return MNL_CB_ERROR;
+
+	mnl_attr_parse_nested(attrs[TIPC_NLA_LINK_PROP], parse_attrs, props);
+	if (!props[*prop])
+		return MNL_CB_ERROR;
+
+	bc_mode = mnl_attr_get_u32(props[*prop]);
+
+	new_json_obj(json);
+	open_json_object(NULL);
+	switch (bc_mode) {
+	case 0x1:
+		print_string(PRINT_ANY, "method", "%s\n", "BROADCAST");
+		break;
+	case 0x2:
+		print_string(PRINT_ANY, "method", "%s\n", "REPLICAST");
+		break;
+	case 0x4:
+		print_string(PRINT_ANY, "method", "%s", "AUTOSELECT");
+		close_json_object();
+		open_json_object(NULL);
+		print_uint(PRINT_ANY, "ratio", " ratio:%u%\n",
+			   mnl_attr_get_u32(props[prop_ratio]));
+		break;
+	default:
+		print_string(PRINT_ANY, NULL, "UNKNOWN\n", NULL);
+		break;
+	}
+	close_json_object();
+	delete_json_obj();
+	return MNL_CB_OK;
+}
+
+static void cmd_link_get_bcast_help(struct cmdl *cmdl)
+{
+	fprintf(stderr, "Usage: %s link get PPROPERTY\n\n"
+		"PROPERTIES\n"
+		" broadcast             - Get link broadcast\n",
+		cmdl->argv[0]);
+}
+
+static int cmd_link_get_bcast(struct nlmsghdr *nlh, const struct cmd *cmd,
+			     struct cmdl *cmdl, void *data)
+{
+	int prop = TIPC_NLA_PROP_BROADCAST;
+	char buf[MNL_SOCKET_BUFFER_SIZE];
+	struct nlattr *attrs;
+
+	if (help_flag) {
+		(cmd->help)(cmdl);
+		return -EINVAL;
+	}
+
+	nlh = msg_init(buf, TIPC_NL_LINK_GET);
+	if (!nlh) {
+		fprintf(stderr, "error, message initialisation failed\n");
+		return -1;
+	}
+	attrs = mnl_attr_nest_start(nlh, TIPC_NLA_LINK);
+	/* Direct to broadcast-link setting */
+	mnl_attr_put_strz(nlh, TIPC_NLA_LINK_NAME, tipc_bclink_name);
+	mnl_attr_nest_end(nlh, attrs);
+	return msg_doit(nlh, cmd_link_get_bcast_cb, &prop);
+}
+
 static int cmd_link_get(struct nlmsghdr *nlh, const struct cmd *cmd,
 			struct cmdl *cmdl, void *data)
 {
@@ -186,6 +268,7 @@ static int cmd_link_get(struct nlmsghdr *nlh, const struct cmd *cmd,
 		{ PRIORITY_STR,	cmd_link_get_prop,	cmd_link_get_help },
 		{ TOLERANCE_STR,	cmd_link_get_prop,	cmd_link_get_help },
 		{ WINDOW_STR,	cmd_link_get_prop,	cmd_link_get_help },
+		{ BROADCAST_STR, cmd_link_get_bcast, cmd_link_get_bcast_help },
 		{ NULL }
 	};
 
-- 
2.17.1