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87f2bd3c0c
Currently named as hypervObjecUnified to keep code
compilable/functional until all bits are in place.
This struct is a result of unserializing WMI request response.
Therefore, it needs to be able to deal with different "versions" of the
same WMI class. To accomplish this, the "data" member was turned in to
a union which:
* has a "common" member that contains only WMI class fields that are
safe to access and are present in all "versions". This is ensured by
the code generator that takes care of proper struct memory alignment
between "common", "v1", "v2" etc members. This memeber is to be used
by the driver code wherever the API implementation can be shared for
all supported hyper-v versions.
* the "v1" and "v2" member can be used by the driver code to handle
version specific cases.
Example:
Msvm_ComputerSystem *vm = NULL;
...
hypervGetVirtualMachineList(priv, wqlQuery, *vm);
...
/* safe for "v1" and "v2" */
char *vmName = vm->data.common->Name;
/* or if one really needs special handling for "v2" */
if (priv->wmiVersion == HYPERV_WMI_VERSION_V2) {
char *foo = vm->data.v2->SomeV2OnlyField;
}
In other words, driver should not concern itself with existence of "v1"
or "v2" of WMI class unless absolutely necessary.
LibVirt : simple API for virtualization
Libvirt is a C toolkit to interact with the virtualization capabilities
of recent versions of Linux (and other OSes). It is free software
available under the GNU Lesser General Public License. Virtualization of
the Linux Operating System means the ability to run multiple instances of
Operating Systems concurrently on a single hardware system where the basic
resources are driven by a Linux instance. The library aim at providing
long term stable C API initially for the Xen paravirtualization but
should be able to integrate other virtualization mechanisms if needed.
Daniel Veillard <veillard@redhat.com>