As discussed here:
https://www.redhat.com/archives/libvir-list/2011-August/msg00361.htmlhttps://www.redhat.com/archives/libvir-list/2011-August/msg00552.html
Adds snapshot attribute and transient sub-element:
<devices>
<disk type=... snapshot='no|internal|external'>
...
<transient/>
</disk>
</devices>
* docs/schemas/domaincommon.rng (snapshot): New define.
(disk): Add snapshot and persistent attributes.
* docs/formatdomain.html.in: Document them.
* src/conf/domain_conf.h (virDomainDiskSnapshot): New enum.
(_virDomainDiskDef): New fields.
* tests/qemuxml2argvdata/qemuxml2argv-disk-transient.xml: New
test of rng, no args counterpart until qemu support is complete.
* tests/qemuxml2argvdata/qemuxml2argv-disk-snapshot.args: New
file, snapshot attribute does not affect args.
* tests/qemuxml2argvdata/qemuxml2argv-disk-snapshot.xml: Likewise.
* tests/qemuxml2argvtest.c (mymain): Run new test.
This patch will probably cause merge conflicts to those trying
to do backports. The end goal is simple - domaincommon.rng
should be the state of domain.rng pre-patch, with a few lines
tweaked in the header, while domain.rng post-patch is now just
a shell that includes domaincommon.rng and sets the <start>.
* docs/schemas/domain.rng: Move guts...
* docs/schemas/domaincommon.rng: ...to new file.
* docs/schemas/domainsnapshot.rng: Allow new xml.
* docs/schemas/Makefile.am (schema_DATA): Distribute new file.
* tests/domainsnapshotxml2xmlout/full_domain.xml: New test.
* libvirt.spec.in (%files client): Ship new file. Sort lines.
* mingw32-libvirt.spec.in: Likewise.