[libvirt] [PATCH 5/5] Allow for a driver specific private data blob in virDomainObjPtr

[Matthias Bolte]

2009/10/14 Daniel P. Berrange <berrange at redhat.com>:
> The virDomainObjPtr object stores state about a running domain.
> This object is shared across all drivers so it is not appropriate
> to include driver specific state here. This patch adds the ability
> to request a blob of private data per domain object instance. The
> driver must provide a allocator & deallocator for this purpose
>
> THis patch abuses the virCapabilitiesPtr structure for storing the
> allocator/deallocator callbacks, since it is already being abused
> for other internal things relating to parsing. This should be moved
> out into a separate object at some point.
>
> * src/conf/capabilities.h: Add privateDataAllocFunc and
>  privateDataFreeFunc fields
> * src/conf/domain_conf.c: Invoke the driver allocators / deallocators
>  when creating/freeing virDomainObjPtr instances.
> * src/conf/domain_conf.h: Pass virCapsPtr into virDomainAssignDef
>  to allow access to the driver specific allocator function
> * src/lxc/lxc_driver.c, src/opennebula/one_driver.c,
>  src/openvz/openvz_driver.c, src/qemu/qemu_driver.c,
>  src/test/test_driver.c, src/uml/uml_driver.c: Update for
>  change in virDomainAssignDef contract
> ---
>  src/conf/capabilities.h     |    2 ++
>  src/conf/domain_conf.c      |   23 +++++++++++++++++++----
>  src/conf/domain_conf.h      |    4 ++++
>  src/lxc/lxc_driver.c        |    6 ++++--
>  src/opennebula/one_driver.c |    6 ++++--
>  src/openvz/openvz_driver.c  |    6 ++++--
>  src/qemu/qemu_driver.c      |    5 +++++
>  src/test/test_driver.c      |   15 ++++++++++-----
>  src/uml/uml_driver.c        |    2 ++
>  9 files changed, 54 insertions(+), 15 deletions(-)
>
> diff --git a/src/conf/capabilities.h b/src/conf/capabilities.h
> index 2f24605..7234cf4 100644
> --- a/src/conf/capabilities.h
> +++ b/src/conf/capabilities.h
> @@ -115,6 +115,8 @@ struct _virCaps {
>     virCapsGuestPtr *guests;
>     unsigned char macPrefix[VIR_MAC_PREFIX_BUFLEN];
>     unsigned int emulatorRequired : 1;
> +    void *(*privateDataAllocFunc)(void);
> +    void (*privateDataFreeFunc)(void *);
>  };

Maybe add a comment here that this should be moved out into a separate
object at some point.

ACK.

PS: What's the specific use case for this?

Matthias