[libvirt] [PATCH] Fix adding ports to OVS bridges without VLAN tags

[Kyle Mestery (kmestery)]

On Aug 30, 2012, at 10:23 PM, Daniel Veillard wrote:
> On Thu, Aug 30, 2012 at 04:38:06PM -0400, Kyle Mestery wrote:
>> The introduction of the new VLAN code, along with the fix
>> from 5e465df6be8bcb00f0b4bff831e91f4042fae272, caused the
>> addition of OVS ports to fail with the following message:
>> 
>> ovs-vsctl: 00002|vsctl|ERR|: missing column name
>> 
>> This fix takes into account the VLAN arguments are optional,
>> and correctly sets up the command line to run the "ovs-vsctl"
>> command to add ports to the OVS bridge.
>> 
>> Signed-off-by: Kyle Mestery <kmestery at cisco.com>
>> CC: Eric Blake <eblake at redhat.com>
>> ---
>> V2:
>>  - Use virBufferUse() to check if a buffer is in use. Found
>>    by Eric Blake.
>> ---
>> src/util/virnetdevopenvswitch.c | 13 +++++++++----
>> 1 file changed, 9 insertions(+), 4 deletions(-)
>> 
>> diff --git a/src/util/virnetdevopenvswitch.c b/src/util/virnetdevopenvswitch.c
>> index 00271a0..764f478 100644
>> --- a/src/util/virnetdevopenvswitch.c
>> +++ b/src/util/virnetdevopenvswitch.c
>> @@ -104,9 +104,15 @@ int virNetDevOpenvswitchAddPort(const char *brname, const char *ifname,
>>     }
>> 
>>     cmd = virCommandNew(OVSVSCTL);
>> +
>> +    virCommandAddArgList(cmd, "--", "--may-exist", "add-port",
>> +                        brname, ifname, NULL);
>> +
>> +    if (virBufferUse(&buf) != 0)
>> +        virCommandAddArgList(cmd, virBufferCurrentContent(&buf), NULL);
>> +
>>     if (ovsport->profileID[0] == '\0') {
>> -        virCommandAddArgList(cmd, "--", "--may-exist", "add-port",
>> -                        brname, ifname, virBufferCurrentContent(&buf),
>> +        virCommandAddArgList(cmd,
>>                         "--", "set", "Interface", ifname, attachedmac_ex_id,
>>                         "--", "set", "Interface", ifname, ifaceid_ex_id,
>>                         "--", "set", "Interface", ifname, vmid_ex_id,
>> @@ -114,8 +120,7 @@ int virNetDevOpenvswitchAddPort(const char *brname, const char *ifname,
>>                         "external-ids:iface-status=active",
>>                         NULL);
>>     } else {
>> -        virCommandAddArgList(cmd, "--", "--may-exist", "add-port",
>> -                        brname, ifname, virBufferCurrentContent(&buf),
>> +        virCommandAddArgList(cmd,
>>                         "--", "set", "Interface", ifname, attachedmac_ex_id,
>>                         "--", "set", "Interface", ifname, ifaceid_ex_id,
>>                         "--", "set", "Interface", ifname, vmid_ex_id,
> 
>  Okay, ACK,
> 
>  pushed, thanks !
> 
> Still there is something which looks wrong, if we don't have a profileID
> why do we end up with "" instead of NULL ? I'm seeing various tests for
> profileID[0] over conf/*.c and util/*.c , and that sounds wrong to me.
> if there is no data, store NULL ! Then test for profileID instead of
> profileID[0]. Then there is no risk of a crash because abscence of data
> led to NULL instead of an empty string, the code is more resilient !
> 
>  I expect a followup patch cleaning this up, but after 0.10.1 ...
>  thanks !
> 
Thanks Daniel, I'll work on the followup patch today.

Kyle

> Daniel