On Tue, Aug 09, 2016 at 05:48:45PM +0800, Chen Hanxiao wrote:
At 2016-08-08 23:00:38, "Michal Privoznik" <mprivozn@redhat.com> wrote:
Dear list,
while wiring qemu-ga into libvirt I've noticed that it has ability to spawn commands inside guest. I haven't paid much attention to it then as implementing libvirt <-> qemu-ga communication was more important. But lately couple of requests on the list showed up where ability to spawn various commands inside guests would be much appreciated (e.g. when fetching some stats that HV can't know or has no support for yet - free/df/..).
When it comes to spawning commands we distinguish two modes: sync and async. I think we should stick to this on the public API level too. Yet better, we can have async APIs and the sync API would just be a wrapper around async then.
Cool! We should had a API than using qemu monitor command.
...
virStreamEventAddCallback(st, VIR_STREAM_EVENT_READABLE, domainCommandCallback, ...);
/* ... */
virDomainCommandJoin(dom, cmd);
virStreamEventRemoveCallback(con->st)
virDomainCommandFree(cmd);
Do we had timeout mechanism? Some command may hang for a long time in guest.
Yet another reason to not try to re-invent a mechanism for running shell commands in libvirt API, and just run a shell service over a separate virtio-serial port instead. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|