Re: [libvirt] [PATCH v2 1/2] vbox: change how vbox API is initialized.
On Wed, 2016-11-23 at 11:00 -0500, Dawid Zamirski wrote:
On Wed, 2016-11-23 at 08:55 -0500, John Ferlan wrote:
> [...]
> > +
> > +static vboxDriverPtr
> > +vboxGetDriverConnection(void)
> > +{
> > + virMutexLock(&vbox_driver_lock);
> > +
> > + if (vbox_driver) {
> > + virObjectRef(vbox_driver);
> > + } else {
> > + vbox_driver = vboxDriverObjNew();
> > +
> > + if (!vbox_driver) {
> > + virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> > + _("Failed to create vbox driver
> > object."));
> > + return NULL;
> > + }
> > + }
> > +
> > + if (vboxSdkInitialize() < 0 || vboxExtractVersion() < 0) {
>
> In this path should vboxSdkUninitialize be called (since it
> wouldn't
> be
> called in the destroy path)?
If vboxSdkUnintialize fails, VBoxSVC is not started so it does not
need
to be unintialized - which is in line with the sample code included
SDK
where it returns with EXIT_FAILUE in main if pfnClientInifialize
fails.
However, if vboxExtractVersion fails (unlikely) we might want to call
gVBoxAPI.UPFN.Unintialize(vbox_driver) directly (not via
vboxSdkUninitialize as it checks connectionCount > 0 which on failure
would be 0). I've just tested both cases with
gVBoxAPI.UPFN.Unintialize
in the failure path, and calling it does not do any harm in both
cases,
so I guess it would be a good idea to put it there.
Actually, I was wrong in that it's safe to call
gVBoxAPI.UPFN.Unintialize when vboxSdkInitialize fails - I got segfault
when attempting to connect twice in VBOX_RELEASE(data->vboxObject).
It's safe to do this though:
if (vboxSdkInitialize() < 0) {
virObjectUnref(vbox_driver);
virMutexUnlock(&vbox_driver_lock);
return NULL;
}
if (vboxExtractVersion() < 0) {
gVBoxAPI.UPFN.Uninitialize(vbox_driver);
virObjectUnref(vbox_driver);
virMutexUnlock(&vbox_driver_lock);
return NULL;
}
i.e do not uninitalize on initialize failure, but do unintialize on
vboxExractVersion failure.