[libvirt] [PATCHv2 1/2] virsh: add virsh snapshot-current --name

[Daniel Veillard]

On Wed, Aug 10, 2011 at 05:02:36PM -0600, Eric Blake wrote:
> Sometimes, full XML is too much; since most snapshot commands
> operate on a snapshot name, there should be an easy way to get
> at the current snapshot's name.
> 
> * tools/virsh.c (cmdSnapshotCurrent): Add an option.
> * tools/virsh.pod (snapshot-current): Document it.
> ---
> 
> v2: use xpath instead of strstr; replaces:
> https://www.redhat.com/archives/libvir-list/2011-August/msg00329.html
> 
>  tools/virsh.c   |   29 ++++++++++++++++++++++++++---
>  tools/virsh.pod |    4 +++-
>  2 files changed, 29 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/virsh.c b/tools/virsh.c
> index bffec1d..fd64020 100644
> --- a/tools/virsh.c
> +++ b/tools/virsh.c
> @@ -12034,6 +12034,7 @@ static const vshCmdInfo info_snapshot_current[] = {
> 
>  static const vshCmdOptDef opts_snapshot_current[] = {
>      {"domain", VSH_OT_DATA, VSH_OFLAG_REQ, N_("domain name, id or uuid")},
> +    {"name", VSH_OT_BOOL, 0, N_("list the name, rather than the full xml")},
>      {NULL, 0, 0, NULL}
>  };
> 
> @@ -12044,6 +12045,7 @@ cmdSnapshotCurrent(vshControl *ctl, const vshCmd *cmd)
>      bool ret = false;
>      int current;
>      virDomainSnapshotPtr snapshot = NULL;
> +    char *xml = NULL;
> 
>      if (!vshConnectionUsability(ctl, ctl->conn))
>          goto cleanup;
> @@ -12056,7 +12058,7 @@ cmdSnapshotCurrent(vshControl *ctl, const vshCmd *cmd)
>      if (current < 0)
>          goto cleanup;
>      else if (current) {
> -        char *xml;
> +        char *name = NULL;
> 
>          if (!(snapshot = virDomainSnapshotCurrent(dom, 0)))
>              goto cleanup;
> @@ -12065,13 +12067,34 @@ cmdSnapshotCurrent(vshControl *ctl, const vshCmd *cmd)
>          if (!xml)
>              goto cleanup;
> 
> -        vshPrint(ctl, "%s", xml);
> -        VIR_FREE(xml);
> +        if (vshCommandOptBool(cmd, "name")) {
> +            xmlDocPtr xmldoc = NULL;
> +            xmlXPathContextPtr ctxt = NULL;
> +
> +            xmldoc = xmlReadDoc((const xmlChar *) xml, "domainsnapshot.xml",
> +                                NULL, XML_PARSE_NOENT | XML_PARSE_NONET |
> +                                XML_PARSE_NOWARNING);
> +            if (!xmldoc)
> +                goto cleanup;
> +            ctxt = xmlXPathNewContext(xmldoc);
> +            if (!ctxt) {
> +                xmlFreeDoc(xmldoc);
> +            }
> +
> +            name = virXPathString("string(/domainsnapshot/name)", ctxt);
> +            xmlXPathFreeContext(ctxt);
> +            xmlFreeDoc(xmldoc);
> +            if (!name)
> +                goto cleanup;
> +        }
> +
> +        vshPrint(ctl, "%s", name ? name : xml);
>      }
> 
>      ret = true;
> 
>  cleanup:
> +    VIR_FREE(xml);
>      if (snapshot)
>          virDomainSnapshotFree(snapshot);
>      if (dom)
> diff --git a/tools/virsh.pod b/tools/virsh.pod
> index ec778bf..53376d6 100644
> --- a/tools/virsh.pod
> +++ b/tools/virsh.pod
> @@ -1569,9 +1569,11 @@ Create a snapshot for domain I<domain> with the given <name> and
>  value.  If I<--print-xml> is specified, then XML appropriate for
>  I<snapshot-create> is output, rather than actually creating a snapshot.
> 
> -=item B<snapshot-current> I<domain>
> +=item B<snapshot-current> I<domain> [I<--name>]
> 
>  Output the snapshot XML for the domain's current snapshot (if any).
> +If I<--name> is specified, just list the snapshot name instead of the
> +full xml.
> 
>  =item B<snapshot-list> I<domain>

  ACK, this is really more convenient in most cases,

Daniel

-- 
Daniel Veillard      | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
daniel at veillard.com  | Rpmfind RPM search engine http://rpmfind.net/
http://veillard.com/ | virtualization library  http://libvirt.org/