Re: [PATCH] iproute2: show network device dependency tree

[Jiri Pirko <jiri@resnulli.us>]

Sat, Feb 25, 2017 at 05:59:00PM CET, zaboj.campula@post.cz wrote:
>Add the argument '-tree' to ip-link to show network devices dependency tree.
>
>Example:
>
>$ ip -tree link
>eth0
>    bond0
>eth1
>    bond0
>eth2
>    bond1
>eth3
>    bond1


Hmm, what is this good for? I'm probably missing something...



>
>Signed-off-by: Zaboj Campula <zaboj.campula@post.cz>
>---
> include/utils.h |  1 +
> ip/ip.c         |  5 ++-
> ip/ipaddress.c  | 97 ++++++++++++++++++++++++++++++++++++++++++++++++---------
> 3 files changed, 87 insertions(+), 16 deletions(-)
>
>diff --git a/include/utils.h b/include/utils.h
>index 22369e0..f1acf4d 100644
>--- a/include/utils.h
>+++ b/include/utils.h
>@@ -20,6 +20,7 @@ extern int show_raw;
> extern int resolve_hosts;
> extern int oneline;
> extern int brief;
>+extern int tree;;
> extern int timestamp;
> extern int timestamp_short;
> extern const char * _SL_;
>diff --git a/ip/ip.c b/ip/ip.c
>index 07050b0..29747a5 100644
>--- a/ip/ip.c
>+++ b/ip/ip.c
>@@ -33,6 +33,7 @@ int show_details;
> int resolve_hosts;
> int oneline;
> int brief;
>+int tree;
> int timestamp;
> const char *_SL_;
> int force;
>@@ -57,7 +58,7 @@ static void usage(void)
> "                    -h[uman-readable] | -iec |\n"
> "                    -f[amily] { inet | inet6 | ipx | dnet | mpls | bridge | link } |\n"
> "                    -4 | -6 | -I | -D | -B | -0 |\n"
>-"                    -l[oops] { maximum-addr-flush-attempts } | -br[ief] |\n"
>+"                    -l[oops] { maximum-addr-flush-attempts } | -br[ief] | -tr[ee] |\n"
> "                    -o[neline] | -t[imestamp] | -ts[hort] | -b[atch] [filename] |\n"
> "                    -rc[vbuf] [size] | -n[etns] name | -a[ll] | -c[olor]}\n");
> 	exit(-1);
>@@ -257,6 +258,8 @@ int main(int argc, char **argv)
> 			batch_file = argv[1];
> 		} else if (matches(opt, "-brief") == 0) {
> 			++brief;
>+		} else if (matches(opt, "-tree") == 0) {
>+			++tree;
> 		} else if (matches(opt, "-rcvbuf") == 0) {
> 			unsigned int size;
> 
>diff --git a/ip/ipaddress.c b/ip/ipaddress.c
>index 242c6ea..5ebcb1a 100644
>--- a/ip/ipaddress.c
>+++ b/ip/ipaddress.c
>@@ -1534,6 +1534,69 @@ static int iplink_filter_req(struct nlmsghdr *nlh, int reqlen)
> 	return 0;
> }
> 
>+static int has_master(struct nlmsg_chain *linfo, int index)
>+{
>+	struct nlmsg_list *l;
>+	struct rtattr *tb[IFLA_MAX+1];
>+	int len;
>+	for (l = linfo->head; l; l = l->next) {
>+		struct ifinfomsg *ifi = NLMSG_DATA(&l->h);
>+		len = l->h.nlmsg_len;
>+		len -= NLMSG_LENGTH(sizeof(*ifi));
>+		parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
>+		if (tb[IFLA_MASTER] && *(int *)RTA_DATA(tb[IFLA_MASTER]) == index)
>+			return 1;
>+	}
>+	return 0;
>+}
>+
>+static struct nlmsg_list *get_master(struct nlmsg_chain *linfo, struct rtattr **tb)
>+{
>+	struct nlmsg_list *l;
>+	if (tb[IFLA_MASTER]) {
>+		int master = *(int *)RTA_DATA(tb[IFLA_MASTER]);
>+		for (l = linfo->head; l; l = l->next) {
>+			struct ifinfomsg *ifi = NLMSG_DATA(&l->h);
>+			if (ifi->ifi_index == master)
>+				return l;
>+		}
>+	}
>+	return NULL;
>+}
>+
>+static void print_dev_tree_item(struct nlmsg_chain *linfo, struct nlmsg_list *l, int indent) {
>+	char *name;
>+	int len;
>+	struct ifinfomsg *ifi = NLMSG_DATA(&l->h);
>+	struct rtattr *tb[IFLA_MAX+1];
>+	len = l->h.nlmsg_len;
>+	len -= NLMSG_LENGTH(sizeof(*ifi));
>+	parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
>+	name = (char *)(tb[IFLA_IFNAME] ? rta_getattr_str(tb[IFLA_IFNAME]) : "<nil>");
>+
>+	printf("%*s%s\n", indent * 4, "", name);
>+
>+	struct nlmsg_list *master = get_master(linfo, tb);
>+	if (master) {
>+		if (indent > 8) {
>+			printf("%*s...\n", (indent + 1) * 4, "");
>+		} else {
>+			print_dev_tree_item(linfo, master, indent + 1);
>+		}
>+	}
>+}
>+
>+static void print_devtree(struct nlmsg_chain *linfo)
>+{
>+	struct nlmsg_list *l;
>+	for (l = linfo->head; l; l = l->next) {
>+		struct ifinfomsg *ifi = NLMSG_DATA(&l->h);
>+		if (!has_master(linfo, ifi->ifi_index)) {
>+			print_dev_tree_item(linfo, l, 0);
>+		}
>+	}
>+}
>+
> static int ipaddr_list_flush_or_save(int argc, char **argv, int action)
> {
> 	struct nlmsg_chain linfo = { NULL, NULL};
>@@ -1742,23 +1805,27 @@ static int ipaddr_list_flush_or_save(int argc, char **argv, int action)
> 		ipaddr_filter(&linfo, &ainfo);
> 	}
> 
>-	for (l = linfo.head; l; l = l->next) {
>-		int res = 0;
>-		struct ifinfomsg *ifi = NLMSG_DATA(&l->h);
>-
>-		if (brief) {
>-			if (print_linkinfo_brief(NULL, &l->h, stdout) == 0)
>+	if (tree) {
>+		print_devtree(&linfo);
>+	} else {
>+		for (l = linfo.head; l; l = l->next) {
>+			int res = 0;
>+			struct ifinfomsg *ifi = NLMSG_DATA(&l->h);
>+
>+			 if (brief) {
>+				if (print_linkinfo_brief(NULL, &l->h, stdout) == 0)
>+					if (filter.family != AF_PACKET)
>+						print_selected_addrinfo(ifi,
>+									ainfo.head,
>+									stdout);
>+			} else if (no_link ||
>+				 (res = print_linkinfo(NULL, &l->h, stdout)) >= 0) {
> 				if (filter.family != AF_PACKET)
> 					print_selected_addrinfo(ifi,
>-								ainfo.head,
>-								stdout);
>-		} else if (no_link ||
>-			 (res = print_linkinfo(NULL, &l->h, stdout)) >= 0) {
>-			if (filter.family != AF_PACKET)
>-				print_selected_addrinfo(ifi,
>-							ainfo.head, stdout);
>-			if (res > 0 && !do_link && show_stats)
>-				print_link_stats(stdout, &l->h);
>+								ainfo.head, stdout);
>+				if (res > 0 && !do_link && show_stats)
>+					print_link_stats(stdout, &l->h);
>+			}
> 		}
> 	}
> 	fflush(stdout);
>-- 
>2.9.3
>