ipneigh: add support to print brief output of neigh cache in tabular format

Make use of the already available brief flag and print the basic details of
the IPv4 or IPv6 neighbour cache in a tabular format for better readability
when the brief output is expected.

$ ip -br neigh
172.16.12.100                           bridge0          b0:fc:36:2f:07:43
172.16.12.174                           bridge0          8c:16:45:2f:bc:1c
172.16.12.250                           bridge0          04:d9:f5:c1:0c:74
fe80::267b:9f70:745e:d54d               bridge0          b0:fc:36:2f:07:43
fd16:a115:6a62:0:8744:efa1:9933:2c4c    bridge0          8c:16:45:2f:bc:1c
fe80::6d9:f5ff:fec1:c74                 bridge0          04:d9:f5:c1:0c:74

And add "ip neigh show" to the list of ip sub commands mentioned in the man
page that support the brief output in tabular format.

Signed-off-by: Gokul Sivakumar <gokulkumar792@gmail.com>
Signed-off-by: David Ahern <dsahern@kernel.org>

diff --git a/ip/ipneigh.c b/ip/ipneigh.c
index 2d6b7f5873e167dbc8308fc84b6679c310c617dd..95bde520fbfc60d34abb706c823839a5323bff31 100644 (file)
--- a/ip/ipneigh.c
+++ b/ip/ipneigh.c
@@ -251,6 +251,51 @@ static void print_neigh_state(unsigned int nud)
        close_json_array(PRINT_JSON, NULL);
 }
 
+static int print_neigh_brief(FILE *fp, struct ndmsg *r, struct rtattr *tb[])
+{
+       if (tb[NDA_DST]) {
+               const char *dst;
+               int family = r->ndm_family;
+
+               if (family == AF_BRIDGE) {
+                       if (RTA_PAYLOAD(tb[NDA_DST]) == sizeof(struct in6_addr))
+                               family = AF_INET6;
+                       else
+                               family = AF_INET;
+               }
+
+               dst = format_host_rta(family, tb[NDA_DST]);
+               print_color_string(PRINT_ANY, ifa_family_color(family),
+                                  "dst", "%-39s ", dst);
+       }
+
+       if (!filter.index && r->ndm_ifindex) {
+               print_color_string(PRINT_ANY, COLOR_IFNAME,
+                                  "dev", "%-16s ",
+                                  ll_index_to_name(r->ndm_ifindex));
+       }
+
+       if (tb[NDA_LLADDR]) {
+               const char *lladdr;
+
+               SPRINT_BUF(b1);
+
+               lladdr = ll_addr_n2a(RTA_DATA(tb[NDA_LLADDR]),
+                                    RTA_PAYLOAD(tb[NDA_LLADDR]),
+                                    ll_index_to_type(r->ndm_ifindex),
+                                    b1, sizeof(b1));
+
+               print_color_string(PRINT_ANY, COLOR_MAC,
+                                  "lladdr", "%s", lladdr);
+       }
+
+       print_string(PRINT_FP, NULL, "%s", "\n");
+       close_json_object();
+       fflush(fp);
+
+       return 0;
+}
+
 int print_neigh(struct nlmsghdr *n, void *arg)
 {
        FILE *fp = (FILE *)arg;
@@ -337,6 +382,9 @@ int print_neigh(struct nlmsghdr *n, void *arg)
        else if (n->nlmsg_type == RTM_GETNEIGH)
                print_null(PRINT_ANY, "miss", "%s ", "miss");
 
+       if (brief)
+               return print_neigh_brief(fp, r, tb);
+
        if (tb[NDA_DST]) {
                const char *dst;
                int family = r->ndm_family;
@@ -412,7 +460,7 @@ int print_neigh(struct nlmsghdr *n, void *arg)
 
        print_string(PRINT_FP, NULL, "\n", "");
        close_json_object();
-       fflush(stdout);
+       fflush(fp);
 
        return 0;
 }

diff --git a/man/man8/ip.8 b/man/man8/ip.8
index c9f7671e591f070aa94079438fd2984086cb70e2..3f572889386a26acabd9112a1341fc12f7e4e3ca 100644 (file)
--- a/man/man8/ip.8
+++ b/man/man8/ip.8
@@ -227,7 +227,7 @@ print human readable rates in IEC units (e.g. 1Ki = 1024).
 .BR "\-br" , " \-brief"
 Print only basic information in a tabular format for better
 readability. This option is currently only supported by
-.BR "ip addr show " and " ip link show " commands.
+.BR "ip addr show ", " ip link show " & " ip neigh show " commands.
 
 .TP
 .BR "\-j", " \-json"