[ovs-dev] [PATCHv2] ovs-ofctl: Use port description stat to look up ports when necessary.

[Justin Pettit]

On May 8, 2012, at 10:47 AM, Ben Pfaff wrote:

> On Tue, May 08, 2012 at 10:42:11AM -0700, Justin Pettit wrote:
>> Not all ports may fit in a Features Reply, so if that's the case, then
>> use the new port description stat message for looking up ports.
>> 
>> Signed-off-by: Justin Pettit <jpettit at nicira.com>
> 
> All I noticed is that in fetch_port_by_stats() we should check that
> the reply is actually a port_desc stats reply (perhaps with
> ofputil_decode_msg_type()), since right now AFAICT it will try to
> interpret an error reply as a stats reply, which probably will work
> out badly.


Good point.  How about the incremental at the end of the message?

--Justin


--- a/utilities/ovs-ofctl.c
+++ b/utilities/ovs-ofctl.c
@@ -610,8 +610,16 @@ fetch_port_by_stats(const char *vconn_name,
         run(vconn_recv_block(vconn, &reply), "OpenFlow packet receive failed");
         recv_xid = ((struct ofp_header *) reply->data)->xid;
         if (send_xid == recv_xid) {
+            const struct ofputil_msg_type *type;
             struct ofp_stats_msg *osm;
 
+            ofputil_decode_msg_type(reply->data, &type);
+            if (ofputil_msg_type_code(type) != OFPUTIL_OFPST_PORT_DESC_REPLY) {
+                ovs_fatal(0, "received bad reply: %s",
+                          ofp_to_string(reply->data, reply->size,
+                                        verbosity + 1));
+            }
+
             osm = ofpbuf_at(reply, 0, sizeof *osm);
             done = !osm || !(ntohs(osm->flags) & OFPSF_REPLY_MORE);