lib: add printfrr to json string helpers

... these should probably have been added ages ago.
`json_object_string_addf(json, "key", "%pFX", prefix)` is super useful.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/lib/json.c b/lib/json.c
index cfba6ea3b6..854a3d59d1 100644
--- a/lib/json.c
+++ b/lib/json.c
@@ -39,17 +39,41 @@ bool use_json(const int argc, struct cmd_token *argv[])
 	return false;
 }
 
+struct json_object *json_object_new_stringv(const char *fmt, va_list args)
+{
+	struct json_object *ret;
+	char *text, buf[256];
+
+	text = vasnprintfrr(MTYPE_TMP, buf, sizeof(buf), fmt, args);
+	ret = json_object_new_string(text);
+
+	if (text != buf)
+		XFREE(MTYPE_TMP, text);
+	return ret;
+}
+
 void json_array_string_add(json_object *json, const char *str)
 {
 	json_object_array_add(json, json_object_new_string(str));
 }
 
+void json_array_string_addv(json_object *json, const char *fmt, va_list args)
+{
+	json_object_array_add(json, json_object_new_stringv(fmt, args));
+}
+
 void json_object_string_add(struct json_object *obj, const char *key,
 			    const char *s)
 {
 	json_object_object_add(obj, key, json_object_new_string(s));
 }
 
+void json_object_string_addv(struct json_object *obj, const char *key,
+			     const char *fmt, va_list args)
+{
+	json_object_object_add(obj, key, json_object_new_stringv(fmt, args));
+}
+
 void json_object_int_add(struct json_object *obj, const char *key, int64_t i)
 {
 	json_object_object_add(obj, key, json_object_new_int64(i));