Subject: [PATCH iproute2-next 3/4] bridge: add json support for link command

From: Stephen Hemminger <[email-masked]>
Date: Sun, 18 Feb 2018 19:18:17 -0800

Add json output for bridge link show command.
This also changes the output format slightly for the non JSON case so
that it has same format as the ip link show command.

Signed-off-by: Stephen Hemminger <[email-masked]>
---
 bridge/link.c | 304 ++++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 188 insertions(+), 116 deletions(-)

diff --git a/bridge/link.c b/bridge/link.c
index 870ebe050477..12cc995e05e3 100644
--- a/bridge/link.c
+++ b/bridge/link.c
@@ -12,6 +12,7 @@
 #include <string.h>
 #include <stdbool.h>
 
+#include "json_print.h"
 #include "libnetlink.h"
 #include "utils.h"
 #include "br_common.h"
@@ -26,15 +27,27 @@ static const char *port_states[] = {
 	[BR_STATE_BLOCKING] = "blocking",
 };
 
-static void print_link_flags(FILE *fp, unsigned int flags)
+
+static const char *oper_states[] = {
+	"UNKNOWN", "NOTPRESENT", "DOWN", "LOWERLAYERDOWN",
+	"TESTING", "DORMANT",	 "UP"
+};
+
+static const char *hw_mode[] = {
+	"VEB", "VEPA"
+};
+
+static void print_link_flags(FILE *fp, unsigned int flags, unsigned int mdown)
 {
-	fprintf(fp, "<");
+	open_json_array(PRINT_ANY, is_json_context() ? "flags" : "<");
 	if (flags & IFF_UP && !(flags & IFF_RUNNING))
-		fprintf(fp, "NO-CARRIER%s", flags ? "," : "");
+		print_string(PRINT_ANY, NULL,
+			     flags ? "%s," : "%s", "NO-CARRIER");
 	flags &= ~IFF_RUNNING;
-#define _PF(f) if (flags&IFF_##f) { \
-		  flags &= ~IFF_##f ; \
-		  fprintf(fp, #f "%s", flags ? "," : ""); }
+
+#define _PF(f) if (flags&IFF_##f) {					\
+		flags &= ~IFF_##f ;					\
+		print_string(PRINT_ANY, NULL, flags ? "%s," : "%s", #f); }
 	_PF(LOOPBACK);
 	_PF(BROADCAST);
 	_PF(POINTOPOINT);
@@ -55,44 +68,136 @@ static void print_link_flags(FILE *fp, unsigned int flags)
 	_PF(ECHO);
 #undef _PF
 	if (flags)
-		fprintf(fp, "%x", flags);
-	fprintf(fp, "> ");
+		print_hex(PRINT_ANY, NULL, "%x", flags);
+	if (mdown)
+		print_string(PRINT_ANY, NULL, ",%s", "M-DOWN");
+	close_json_array(PRINT_ANY, "> ");
 }
 
-static const char *oper_states[] = {
-	"UNKNOWN", "NOTPRESENT", "DOWN", "LOWERLAYERDOWN",
-	"TESTING", "DORMANT",	 "UP"
-};
-
-static const char *hw_mode[] = {"VEB", "VEPA"};
-
 static void print_operstate(FILE *f, __u8 state)
 {
-	if (state >= ARRAY_SIZE(oper_states))
-		fprintf(f, "state %#x ", state);
-	else
-		fprintf(f, "state %s ", oper_states[state]);
+	if (state >= ARRAY_SIZE(oper_states)) {
+		print_0xhex(PRINT_ANY, "operstate", "operstat %#x", state);
+	} else {
+		if (is_json_context())
+			print_string(PRINT_JSON,
+				     "operstate",
+				     NULL, oper_states[state]);
+		else {
+			fprintf(f, "state ");
+			color_fprintf(f, oper_state_color(state),
+				      "%s ", oper_states[state]);
+		}
+	}
 }
 
-static void print_portstate(FILE *f, __u8 state)
+static void print_portstate(__u8 state)
 {
 	if (state <= BR_STATE_BLOCKING)
-		fprintf(f, "state %s ", port_states[state]);
+		print_string(PRINT_ANY, "state",
+			     "state %s ", port_states[state]);
 	else
-		fprintf(f, "state (%d) ", state);
+		print_uint(PRINT_ANY, "state",
+			     "state (%d) ", state);
 }
 
-static void print_onoff(FILE *f, char *flag, __u8 val)
+static void print_onoff(FILE *fp, const char *flag, __u8 val)
 {
-	fprintf(f, "%s %s ", flag, val ? "on" : "off");
+	if (is_json_context())
+		print_bool(PRINT_JSON, flag, NULL, val);
+	else
+		fprintf(fp, "%s %s ", flag, val ? "on" : "off");
 }
 
-static void print_hwmode(FILE *f, __u16 mode)
+static void print_hwmode(__u16 mode)
 {
 	if (mode >= ARRAY_SIZE(hw_mode))
-		fprintf(f, "hwmode %#hx ", mode);
+		print_0xhex(PRINT_ANY, "hwmode",
+			    "hwmode %#hx ", mode);
 	else
-		fprintf(f, "hwmode %s ", hw_mode[mode]);
+		print_string(PRINT_ANY, "hwmode",
+			     "hwmode %s ", hw_mode[mode]);
+}
+
+static void print_protinfo(FILE *fp, struct rtattr *attr)
+{
+	if (attr->rta_type & NLA_F_NESTED) {
+		struct rtattr *prtb[IFLA_BRPORT_MAX + 1];
+
+		parse_rtattr_nested(prtb, IFLA_BRPORT_MAX, attr);
+
+		if (prtb[IFLA_BRPORT_STATE])
+			print_portstate(rta_getattr_u8(prtb[IFLA_BRPORT_STATE]));
+
+		if (prtb[IFLA_BRPORT_PRIORITY])
+			print_uint(PRINT_ANY, "priority",
+				   "priority %u ",
+				   rta_getattr_u16(prtb[IFLA_BRPORT_PRIORITY]));
+
+		if (prtb[IFLA_BRPORT_COST])
+			print_uint(PRINT_ANY, "cost",
+				   "cost %u ",
+				   rta_getattr_u32(prtb[IFLA_BRPORT_COST]));
+
+		if (!show_details)
+			return;
+
+		if (!is_json_context())
+			fprintf(fp, "%s    ", _SL_);
+
+		if (prtb[IFLA_BRPORT_MODE])
+			print_onoff(fp, "hairpin",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_MODE]));
+		if (prtb[IFLA_BRPORT_GUARD])
+			print_onoff(fp, "guard",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_GUARD]));
+		if (prtb[IFLA_BRPORT_PROTECT])
+			print_onoff(fp, "root_block",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_PROTECT]));
+		if (prtb[IFLA_BRPORT_FAST_LEAVE])
+			print_onoff(fp, "fastleave",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_FAST_LEAVE]));
+		if (prtb[IFLA_BRPORT_LEARNING])
+			print_onoff(fp, "learning",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_LEARNING]));
+		if (prtb[IFLA_BRPORT_LEARNING_SYNC])
+			print_onoff(fp, "learning_sync",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_LEARNING_SYNC]));
+		if (prtb[IFLA_BRPORT_UNICAST_FLOOD])
+			print_onoff(fp, "flood",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_UNICAST_FLOOD]));
+		if (prtb[IFLA_BRPORT_MCAST_FLOOD])
+			print_onoff(fp, "mcast_flood",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_MCAST_FLOOD]));
+		if (prtb[IFLA_BRPORT_NEIGH_SUPPRESS])
+			print_onoff(fp, "neigh_suppress",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_NEIGH_SUPPRESS]));
+		if (prtb[IFLA_BRPORT_VLAN_TUNNEL])
+			print_onoff(fp, "vlan_tunnel",
+				    rta_getattr_u8(prtb[IFLA_BRPORT_VLAN_TUNNEL]));
+	} else
+		print_portstate(rta_getattr_u8(attr));
+}
+
+
+/*
+ * This is reported by HW devices that have some bridging
+ * capabilities.
+ */
+static void print_af_spec(FILE *fp, struct rtattr *attr)
+{
+	struct rtattr *aftb[IFLA_BRIDGE_MAX+1];
+
+	parse_rtattr_nested(aftb, IFLA_BRIDGE_MAX, attr);
+
+	if (aftb[IFLA_BRIDGE_MODE])
+		print_hwmode(rta_getattr_u16(aftb[IFLA_BRIDGE_MODE]));
+
+	if (!show_details)
+		return;
+
+	if (aftb[IFLA_BRIDGE_VLAN_INFO])
+		print_vlan_info(fp, aftb[IFLA_BRIDGE_VLAN_INFO]);
 }
 
 int print_linkinfo(const struct sockaddr_nl *who,
@@ -102,6 +207,7 @@ int print_linkinfo(const struct sockaddr_nl *who,
 	int len = n->nlmsg_len;
 	struct ifinfomsg *ifi = NLMSG_DATA(n);
 	struct rtattr *tb[IFLA_MAX+1];
+	unsigned int m_flag = 0;
 
 	len -= NLMSG_LENGTH(sizeof(*ifi));
 	if (len < 0) {
@@ -118,113 +224,75 @@ int print_linkinfo(const struct sockaddr_nl *who,
 	parse_rtattr_flags(tb, IFLA_MAX, IFLA_RTA(ifi), len, NLA_F_NESTED);
 
 	if (tb[IFLA_IFNAME] == NULL) {
-		fprintf(stderr, "BUG: nil ifname\n");
+		fprintf(stderr, "BUG: device with ifindex %d has nil ifname\n",
+			ifi->ifi_index);
 		return -1;
 	}
 
+	open_json_object(NULL);
 	if (n->nlmsg_type == RTM_DELLINK)
-		fprintf(fp, "Deleted ");
-
-	fprintf(fp, "%d: %s ", ifi->ifi_index,
-		tb[IFLA_IFNAME] ? rta_getattr_str(tb[IFLA_IFNAME]) : "<nil>");
-
-	if (tb[IFLA_OPERSTATE])
-		print_operstate(fp, rta_getattr_u8(tb[IFLA_OPERSTATE]));
+		print_bool(PRINT_ANY, "deleted", "Deleted ", true);
+
+	print_int(PRINT_ANY, "ifindex", "%d: ", ifi->ifi_index);
+	if (tb[IFLA_IFNAME]) {
+		print_color_string(PRINT_ANY,
+				   COLOR_IFNAME,
+				   "ifname", "%s",
+				   rta_getattr_str(tb[IFLA_IFNAME]));
+	} else {
+		print_null(PRINT_JSON, "ifname", NULL, NULL);
+		print_color_null(PRINT_FP, COLOR_IFNAME,
+				 "ifname", "%s", "<nil>");
+	}
 
 	if (tb[IFLA_LINK]) {
 		int iflink = rta_getattr_u32(tb[IFLA_LINK]);
 
-		fprintf(fp, "@%s: ",
-			iflink ? ll_index_to_name(iflink) : "NONE");
-	} else
-		fprintf(fp, ": ");
+		if (iflink == 0)
+			print_null(PRINT_ANY, "link", "@%s: ", "NONE");
+		else {
+			if (tb[IFLA_LINK_NETNSID])
+				print_int(PRINT_ANY,
+					  "link_index", "@if%d: ", iflink);
+			else {
+				SPRINT_BUF(b1);
+
+				print_string(PRINT_ANY,
+					     "link",
+					     "@%s: ",
+					     ll_idx_n2a(iflink, b1));
+				m_flag = ll_index_to_flags(iflink);
+				m_flag = !(m_flag & IFF_UP);
+			}
+		}
+	} else {
+		print_string(PRINT_FP, NULL, ": ", NULL);
+	}
+	print_link_flags(fp, ifi->ifi_flags, m_flag);
 
-	print_link_flags(fp, ifi->ifi_flags);
+	if (tb[IFLA_OPERSTATE])
+		print_operstate(fp, rta_getattr_u8(tb[IFLA_OPERSTATE]));
 
 	if (tb[IFLA_MTU])
-		fprintf(fp, "mtu %u ", rta_getattr_u32(tb[IFLA_MTU]));
+		print_int(PRINT_ANY,
+			  "mtu", "mtu %u ",
+			  rta_getattr_u32(tb[IFLA_MTU]));
 
 	if (tb[IFLA_MASTER]) {
-		int master = rta_getattr_u32(tb[IFLA_MASTER]);
+		SPRINT_BUF(b1);
 
-		fprintf(fp, "master %s ", ll_index_to_name(master));
+		print_string(PRINT_ANY, "master", "master %s ",
+			     ll_idx_n2a(rta_getattr_u32(tb[IFLA_MASTER]), b1));
 	}
 
-	if (tb[IFLA_PROTINFO]) {
-		if (tb[IFLA_PROTINFO]->rta_type & NLA_F_NESTED) {
-			struct rtattr *prtb[IFLA_BRPORT_MAX+1];
-
-			parse_rtattr_nested(prtb, IFLA_BRPORT_MAX,
-					    tb[IFLA_PROTINFO]);
-
-			if (prtb[IFLA_BRPORT_STATE])
-				print_portstate(fp,
-						rta_getattr_u8(prtb[IFLA_BRPORT_STATE]));
-			if (prtb[IFLA_BRPORT_PRIORITY])
-				fprintf(fp, "priority %hu ",
-					rta_getattr_u16(prtb[IFLA_BRPORT_PRIORITY]));
-			if (prtb[IFLA_BRPORT_COST])
-				fprintf(fp, "cost %u ",
-					rta_getattr_u32(prtb[IFLA_BRPORT_COST]));
-
-			if (show_details) {
-				fprintf(fp, "%s    ", _SL_);
-
-				if (prtb[IFLA_BRPORT_MODE])
-					print_onoff(fp, "hairpin",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_MODE]));
-				if (prtb[IFLA_BRPORT_GUARD])
-					print_onoff(fp, "guard",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_GUARD]));
-				if (prtb[IFLA_BRPORT_PROTECT])
-					print_onoff(fp, "root_block",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_PROTECT]));
-				if (prtb[IFLA_BRPORT_FAST_LEAVE])
-					print_onoff(fp, "fastleave",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_FAST_LEAVE]));
-				if (prtb[IFLA_BRPORT_LEARNING])
-					print_onoff(fp, "learning",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_LEARNING]));
-				if (prtb[IFLA_BRPORT_LEARNING_SYNC])
-					print_onoff(fp, "learning_sync",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_LEARNING_SYNC]));
-				if (prtb[IFLA_BRPORT_UNICAST_FLOOD])
-					print_onoff(fp, "flood",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_UNICAST_FLOOD]));
-				if (prtb[IFLA_BRPORT_MCAST_FLOOD])
-					print_onoff(fp, "mcast_flood",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_MCAST_FLOOD]));
-				if (prtb[IFLA_BRPORT_NEIGH_SUPPRESS])
-					print_onoff(fp, "neigh_suppress",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_NEIGH_SUPPRESS]));
-				if (prtb[IFLA_BRPORT_VLAN_TUNNEL])
-					print_onoff(fp, "vlan_tunnel",
-						    rta_getattr_u8(prtb[IFLA_BRPORT_VLAN_TUNNEL]));
-			}
-		} else
-			print_portstate(fp, rta_getattr_u8(tb[IFLA_PROTINFO]));
-	}
+	if (tb[IFLA_PROTINFO])
+		print_protinfo(fp, tb[IFLA_PROTINFO]);
 
-	if (tb[IFLA_AF_SPEC]) {
-		/* This is reported by HW devices that have some bridging
-		 * capabilities.
-		 */
-		struct rtattr *aftb[IFLA_BRIDGE_MAX+1];
-
-		parse_rtattr_nested(aftb, IFLA_BRIDGE_MAX, tb[IFLA_AF_SPEC]);
-
-		if (aftb[IFLA_BRIDGE_MODE])
-			print_hwmode(fp, rta_getattr_u16(aftb[IFLA_BRIDGE_MODE]));
-		if (show_details) {
-			if (aftb[IFLA_BRIDGE_VLAN_INFO]) {
-				fprintf(fp, "\n");
-				print_vlan_info(fp, tb[IFLA_AF_SPEC],
-						ifi->ifi_index);
-			}
-		}
-	}
+	if (tb[IFLA_AF_SPEC])
+		print_af_spec(fp, tb[IFLA_AF_SPEC]);
 
-	fprintf(fp, "\n");
+	print_string(PRINT_FP, NULL, "%s", "\n");
+	close_json_object();
 	fflush(fp);
 	return 0;
 }
@@ -499,10 +567,14 @@ static int brlink_show(int argc, char **argv)
 		}
 	}
 
+	new_json_obj(json);
 	if (rtnl_dump_filter(&rth, print_linkinfo, stdout) < 0) {
 		fprintf(stderr, "Dump terminated\n");
 		exit(1);
 	}
+
+	delete_json_obj();
+	fflush(stdout);
 	return 0;
 }
 
-- 
2.16.1