Re: [libvirt] [PATCH v7 14/23] backup: Parse and output backup XML

On Wed, Mar 27, 2019 at 07:14:09 -0500, Eric Blake wrote: > On 3/27/19 7:05 AM, Peter Krempa wrote: > > On Wed, Mar 27, 2019 at 05:10:45 -0500, Eric Blake wrote: > >> Accept XML describing a generic block job, and output it again as > >> needed. This may still need a few tweaks to match the documented XML > >> and RNG schema. > >> > >> Signed-off-by: Eric Blake <eblake(a)redhat.com&gt; > >> --- > >> src/conf/backup_conf.h | 96 +++++++ > >> src/conf/virconftypes.h | 3 + > >> src/conf/Makefile.inc.am | 2 + > >> src/conf/backup_conf.c | 544 +++++++++++++++++++++++++++++++++++++++ > >> src/libvirt_private.syms | 8 +- > >> 5 files changed, 652 insertions(+), 1 deletion(-) > >> create mode 100644 src/conf/backup_conf.h > >> create mode 100644 src/conf/backup_conf.c [...] > >> + if ((cur = virXPathNode(push ? "./target" : "./scratch", ctxt)) && > >> + virDomainDiskSourceParse(cur, ctxt, def->store, 0, xmlopt) < 0) > >> + goto cleanup; > >> + > >> + if (internal) { > >> + int detected; > >> + if (virXPathInt("string(./node/@detected)", ctxt, &detected) < 0) > >> + goto cleanup; > >> + def->store->detected = detected; > >> + def->store->nodeformat = virXPathString("string(./node)", ctxt); > > > > This should not be public name. Current design of nodenames does not > > allow you to depend on the name. > > > > In general, nodenames are a qemu-specific thing thus should not be > > expressed nor documented in the public XML. > > Hence the 'internal' flag; this is ONLY supposed to be output for qemu's > internal storage to /var/lib/libvirt/qemu/domain.xml to persist state > across libvirtd restarts. I also think that by the end of my series, I > was trying to avoid this ever landing on disk, and instead teaching > libvirt to re-parse current node names from QMP on the fly before any > operation where the node names are not still in memory from an earlier time. Okay, so it's a case of technical debt since all this private stuff will later need refactoring to private data callbacks.