[PATCH iproute2-next v2 1/1] tc: add json support in csum action

Add json output support for checksum action.

Example output:

~$ $TC actions add action csum udp continue index 7
~$ $TC actions add action csum icmp iph igmp pipe index 200 cookie 112233
~$ $TC -j actions ls action csum

[{
    "total acts":2
}, {
    "actions": [{
        "order":0,
        "csum":"udp",
        "control_action": {
            "type":"continue"
        },
        "index":7,
        "ref":1,
        "bind":0
    }, {
        "order":1,
        "csum":"iph, icmp, igmp",
        "control_action": {
            "type":"pipe"
        },
        "index":200,
        "ref":1,
        "bind":0,
        "cookie":"112233"
    }]
}]

v2:
    Don't initialized char buf[64];
    Add output example
    
Signed-off-by: Keara Leibovitz <redacted>
---
 tc/m_csum.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/tc/m_csum.c b/tc/m_csum.c
index 8391071d73f2..0bdbcf361a28 100644
--- a/tc/m_csum.c
+++ b/tc/m_csum.c

@@ -162,6 +162,7 @@ print_csum(struct action_util *au, FILE *f, struct rtattr *arg)
 	char *uflag_5 = "";
 	char *uflag_6 = "";
 	char *uflag_7 = "";
+	char buf[64];
 
 	int uflag_count = 0;
 

@@ -198,12 +199,15 @@ print_csum(struct action_util *au, FILE *f, struct rtattr *arg)
 		uflag_1 = "?empty";
 	}
 
-	fprintf(f, "csum (%s%s%s%s%s%s%s) ",
-		uflag_1, uflag_2, uflag_3,
-		uflag_4, uflag_5, uflag_6, uflag_7);
+	snprintf(buf, sizeof(buf), "%s%s%s%s%s%s%s",
+		 uflag_1, uflag_2, uflag_3,
+		 uflag_4, uflag_5, uflag_6, uflag_7);
+	print_string(PRINT_ANY, "csum", "csum (%s) ", buf);
+
 	print_action_control(f, "action ", sel->action, "\n");
-	fprintf(f, "\tindex %u ref %d bind %d", sel->index, sel->refcnt,
-		sel->bindcnt);
+	print_uint(PRINT_ANY, "index", "\tindex %u", sel->index);
+	print_int(PRINT_ANY, "ref", " ref %d", sel->refcnt);
+	print_int(PRINT_ANY, "bind", " bind %d", sel->bindcnt);
 
 	if (show_stats) {
 		if (tb[TCA_CSUM_TM]) {

@@ -212,7 +216,7 @@ print_csum(struct action_util *au, FILE *f, struct rtattr *arg)
 			print_tm(f, tm);
 		}
 	}
-	fprintf(f, "\n");
+	print_string(PRINT_FP, NULL, "%s", "\n");
 
 	return 0;
 }

-- 
2.7.4

On Tue,  5 Jun 2018 16:44:19 -0400
Keara Leibovitz [off-list ref] wrote:

Looks good.
In iproute2 the common macro for declaring these kind of buffers is:
	SPRINT_BUF(buf);

Doesn't matter that much, but nice to have consistency.

On 6/5/18 1:44 PM, Keara Leibovitz wrote:

Add json output support for checksum action.

...

changed that line to 'SPRINT_BUF(buf);' per Stephen's comment and
applied to iproute2-next.