Commit Graph

4 Commits

Author SHA1 Message Date
Eric Blake
02c4e24db7 snapshot: Add accessors for updating snapshot list relations
Rather than allowing a leaky abstraction where multiple drivers have
to open-code operations that update the relations in a
virDomainSnapshotObjList, it is better to add accessor functions so
that updates to relations are maintained closer to the internals.
This patch finishes the job started in the previous patch, by getting
rid of all direct access to nchildren, first_child, or sibling outside
of the lowest level functions, making it easier to refactor later on.

The lone new caller to virDomainSnapshotObjListSize() checks for a
return != 0, because it wants to handles errors (-1, only possible if
the hash table wasn't allocated) and existing snapshots (> 0) in the
same manner; we can drop the check for a current snapshot on the
grounds that there shouldn't be one if there are no snapshots.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:18:33 -05:00
Eric Blake
ced0898f86 snapshot: Add accessor for reparenting snapshot children
Rather than allowing a leaky abstraction where multiple drivers have
to open-code operations that update the relations in a
virDomainSnapshotObjList, it is better to add accessor functions so
that updates to relations are maintained closer to the internals.
This patch starts the task with a single new function:
virDomainSnapshotMoveChildren(). The logic might not be immediately
obvious [okay, that's an understatement - the existing code uses black
magic ;-)], so here's an overview: The old code has an implicit for
loop around each call to qemuDomainSnapshotReparentChildren() by using
virDomainSnapshotForEachChild() (you'll need a wider context than
git's default of 3 lines to see that); the new code has a more visible
for loop. Then it helps if you realize that the code is making two
separate changes to each child object: STRDUP of the new parent name
prior to writing XML files (unchanged), and touching up the pointer to
the parent object (refactored); the end result is the same whether a
single pass made both changes (both in driver code), or whether it is
split into two passes making one change each (one in driver code, the
other in the new accessor).

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:18:25 -05:00
Eric Blake
9b75154c07 snapshot: Break out virDomainSnapshotObjList into its own file
snapshot_conf.h was mixing three separate types: the snapshot
definition, the snapshot object, and the snapshot object list.
Separate out the snapshot object list code into its own file, and
update includes for affected clients.

This is just code motion, but done in preparation of sharing a lot of
the object list code with checkpoints.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-03-15 11:43:09 -05:00
Eric Blake
ca20690e9f snapshot: Break out virDomainSnapshotObj into its own file
snapshot_conf.h was mixing three separate types: the snapshot
definition, the snapshot object, and the snapshot object list.
Separate out the snapshot object code into its own file, which
includes moving a typedef to avoid circular inclusions.

Mostly straight code motion, although I fixed a comment along
the way, now that virDomainSnapshotForEachDescendent now
guarantees a topological visit (missed in b647d219).

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-03-15 11:34:32 -05:00