[libvirt] [PATCH 1/2 v3] Fix virDomainChrDefParseTargetXML() to parse the target port if available

[Michal Novotny]

[snip]
> We've got other code in domain_conf.c that assigns ports
> to the first available slot; for example, look near line 5628 at how
> virtio-serial ports are assigned using maxport and traversal of all
> previously assigned ports.
>
Is the code correct there?

The code is:

         if (chr->info.type == 
VIR_DOMAIN_DEVICE_ADDRESS_TYPE_VIRTIO_SERIAL &&
             chr->info.addr.vioserial.port == 0) {
             int maxport = 0;
             int j;
             for (j = 0 ; j < i ; j++) {
                 virDomainChrDefPtr thischr = def->channels[j];
                 if (thischr->info.type == 
VIR_DOMAIN_DEVICE_ADDRESS_TYPE_VIRTIO_SERIAL &&
                     thischr->info.addr.vioserial.controller == 
chr->info.addr.vioserial.controller &&
                     thischr->info.addr.vioserial.bus == 
chr->info.addr.vioserial.bus &&
                     (int)thischr->info.addr.vioserial.port > maxport)
                     maxport = thischr->info.addr.vioserial.port;
             }
             chr->info.addr.vioserial.port = maxport + 1;
         }


That is if it's found you're having maxport set to maximum value + 1, 
that's fine but if it's not found it doesn't start from 0 but it starts 
from number 1 since "chr->info.addr.vioserial.port = maxport + 1;" line. 
Maxport is being set to 0 and when nothing is found then the code is 
"chr->info.addr.vioserial.port = 0 + 1" therefore resulting into 
"chr->info.addr.vioserial.port = 1;". Based on this it doesn't start 
zero-based since this position (port = 0) is unassigned but only next 
position (port = 1) is defined.

Is that behavior correct?

Thanks,
Michal

-- 
Michal Novotny<minovotn at redhat.com>, RHCE
Virtualization Team (xen userspace), Red Hat