Pull out the common parts of virDomainSnapshotDef that will be reused
for virDomainCheckpointDef into a new base class. Adjust all callers
that use the direct fields (some of it is churn that disappears when
the next patch refactors virDomainSnapshotObj; oh well...).
Someday, I hope to switch this type to be a subclass of virObject, but
that requires a more thorough audit of cleanup paths, and besides
minimal incremental changes are easier to review.
As for the choice of naming:
I promised my teenage daughter Evelyn that I'd give her credit for her
contribution to this commit. I asked her "What would be a good name
for a base class for DomainSnapshot and DomainCheckpoint". After
explaining what a base class was (using the classic OOB Square and
Circle inherit from Shape), she came up with "DomainMoment", which is
way better than my initial thought of "DomainPointInTime" or
"DomainPIT".
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
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>
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>
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>
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>
