On Fri, Sep 06, 2019 at 12:12:23PM +0100, Dr. David Alan Gilbert wrote: > * Daniel P. Berrangé (berra...@redhat.com) wrote: > > On Fri, Sep 06, 2019 at 11:23:28AM +0100, Stefan Hajnoczi wrote: > > > On Thu, Sep 05, 2019 at 06:27:32PM +0100, Dr. David Alan Gilbert wrote: > > > > * Stefan Hajnoczi (stefa...@redhat.com) wrote: > > > > > Introduce a DBus server thread that runs alongside the other virtiofsd > > > > > threads. It processes changes to the /org/qemu/virtiofsd object which > > > > > can be accessed at the org.qemu.virtiofsd location on the bus. > > > > > > > > > > This code does not use locking because we are the only writer to the > > > > > int current_log_level variable. More advanced management commands > > > > > would > > > > > require locking to prevent race conditions with the other threads. > > > > > > > > > > Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com> > > > > > > > > OK, that is less complex than I'd feared. > > > > I guess there's something probably nice to do with name/integer mapping > > > > for warning levels that we could use from one of the libraries. > > > > > > I used a free-form string because it's what systemd's LogLevel property > > > also does. But I can investigate the cleanest approach for limiting it > > > to a set of string constants. > > > > There's no concept of "enums" at the DBus protocol level. Sending enums > > in string form is the normal practice - avoiding integer values means > > you are not vulnerable to enum values changing if someone inserts a new > > constant in the middlle of the enum. This same reason is why QAPI uses > > strings for enums instead of ints. > > Oh, I wasn't talking aobut changing protocol; I just meant there was > probably a neater way of doing the string look up than the opencoded way > it was done.
Oh sure, you can declare the enum in a header, and then run glib-mkenums with that header file and it will spit out the code neccessary to register a GEnum class. This gives you ability to do int/string conversions with a simple api https://developer.gnome.org/gobject/stable/gobject-Enumeration-and-Flag-Types.html https://developer.gnome.org/gobject/stable/glib-mkenums.html It makes sense to use this, since virtiofsd is already using GObject via GDbus. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
