Re: [libvirt] [PATCH v4] virsh: add [--domain DOMAIN] option to domxml-to-native DOMAIN COMMAND

On 06/02/2017 11:04 AM, Daniel Liu wrote: > The option allows someone to run domain-to-native on already existing > domain without the need of supplying their XML. It is basically > wrapper around 'virsh dumpxml | virsh domxml-to-native /dev/stdin'. > > Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=835476 > Signed-off-by: Daniel Liu <srwx4096(a)gmail.com&gt; > --- > tools/virsh-domain.c | 51 ++++++++++++++++++++++++++++++++++++++------------- > tools/virsh.pod | 7 ++++--- > 2 files changed, 42 insertions(+), 16 deletions(-) > > diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c > index ccb514ef9..3496359c5 100644 > --- a/tools/virsh-domain.c > +++ b/tools/virsh-domain.c > @@ -9848,9 +9848,13 @@ static const vshCmdOptDef opts_domxmltonative[] = { > .flags = VSH_OFLAG_REQ, > .help = N_("target config data type format") > }, > + {.name = "domain", > + .type = VSH_OT_DATA, > + .flags = VSH_OFLAG_REQ_OPT, > + .help = N_("domain name, id or uuid") > + }, > {.name = "xml", > .type = VSH_OT_DATA, > - .flags = VSH_OFLAG_REQ, > .help = N_("xml data file to export from") > }, > {.name = NULL} > @@ -9859,30 +9863,51 @@ static const vshCmdOptDef opts_domxmltonative[] = { > static bool > cmdDomXMLToNative(vshControl *ctl, const vshCmd *cmd) > { > - bool ret = true; > + bool ret = false; > const char *format = NULL; > - const char *xmlFile = NULL; > - char *configData; > - char *xmlData; > + const char *xml = NULL; nit: no need to change from xmlFile to xml... The less differences the better ;-) > + char *xmlData = NULL; > + char *configData = NULL; nit: no need to change order from original, just add ' = NULL' is fine. > unsigned int flags = 0; > virshControlPtr priv = ctl->privData; > + virDomainPtr dom = NULL; > > if (vshCommandOptStringReq(ctl, cmd, "format", &format) < 0 || > - vshCommandOptStringReq(ctl, cmd, "xml", &xmlFile) < 0) > + vshCommandOptStringReq(ctl, cmd, "xml", &xml) < 0) > return false; > > - if (virFileReadAll(xmlFile, VSH_MAX_XML_FILE, &xmlData) < 0) > - return false; > + VSH_EXCLUSIVE_OPTIONS("domain", "xml"); > > - configData = virConnectDomainXMLToNative(priv->conn, format, xmlData, flags); > - if (configData != NULL) { > - vshPrint(ctl, "%s", configData); > - VIR_FREE(configData); > + if (vshCommandOptBool(cmd, "domain") && > + (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))) > + return false; > + > + if (dom) { > + xmlData = virDomainGetXMLDesc(dom, flags); > + } else if (xml) { > + if (virFileReadAll(xml, VSH_MAX_XML_FILE, &xmlData) < 0) > + goto cleanup; > } else { > - ret = false; > + vshError(ctl, "%s", _("need either domain or domain XML")); > + goto cleanup; > + } > + > + if (!xmlData) { > + vshError(ctl, "%s", _("failed to retrieve XML")); > + goto cleanup; > } > > + if (!(configData = virConnectDomainXMLToNative(priv->conn, format, xmlData, flags))) { > + goto cleanup; > + } else { > + vshPrint(ctl, "%s", configData); > + ret = true; > + } > + > + cleanup: > + virshDomainFree(dom); > VIR_FREE(xmlData); > + VIR_FREE(configData); > return ret; > } > > diff --git a/tools/virsh.pod b/tools/virsh.pod > index aee964689..049c2f3c7 100644 > --- a/tools/virsh.pod > +++ b/tools/virsh.pod > @@ -1433,10 +1433,11 @@ the I<format> argument must be B<qemu-argv>. For Xen hypervisor, the > I<format> argument may be B<xen-xm>, B<xen-xl>, or B<xen-sxpr>. For > LXC hypervisor, the I<format> argument must be B<lxc-tools>. > > -=item B<domxml-to-native> I<format> I<xml> > +=item B<domxml-to-native> I<format> > +{ I<--domain> I<domain-name-or-id-or-uuid> | [I<--xml>] I<xml> } This looks really odd, I think this should be { [I<xml> | [I<--domain> I<domain-name-or-id-uuid>] } I believe that's the way to describe mutually exclusive options where one would be required; otherwise, we have the funky [[ ... ]] which indicates mutually exclusive optional arguments. Search on "{ [" in virsh.pod for some examples. This seems to be the first case where a previously required positional argument can be both a positional and optional as long as the alternative means of describing is provided. Keeping the I<xml> first at least indicates that it can be used *without* the --xml, but is also the "default" when used positionally on the command line. If not used positionally, then the --xml would be required, e.g. if someone used "virsh domxml-to-native --xml @file --format @format". Having the [--domain] indicates that in order to use it, it must have that --domain argument because "virsh domxml-to-native qemu-argv $domainname" would be invalid since the unqualified 2nd argument is expected to be an <xml> file. Whether any of this is written down anywhere - I'm not sure - it's what I've surmised over the few years. > > -Convert the file I<xml> in domain XML format to the native guest > -configuration format named by I<format>. For QEMU/KVM hypervisor, > +Convert the file I<xml> in domain XML format or existing domain to the > +native guest configuration format named by I<format>. For QEMU/KVM hypervisor, > the I<format> argument must be B<qemu-argv>. For Xen hypervisor, the > I<format> argument may be B<xen-xm>, B<xen-xl>, or B<xen-sxpr>. For > LXC hypervisor, the I<format> argument must be B<lxc-tools>. > Convert the file I<xml> into domain XML format or convert an existing I<--domain> to the native guest configuration format named by I<format>. The I<xml> and I<--domain> arguments are mutually exclusive. John