[libvirt] [PATCH 0/4] qemu: export disk snapshot capability

Francesco Romani fromani at redhat.com
Fri Jan 17 15:31:47 UTC 2014

This patch series extend the QEMU capabilities XML to report
if the underlying QEMU binary supports, or not, the live
disk snapshotting.

Without this patch series, the only way to know if QEMU
has this support is to actually request a disk snapshot and
to see what happens.

The change is split in four patches:

* patch #1
actually adds the new element in the QEMU capabilities XML.
formatcaps.html.in wasn't very detailed about the actual XML format,
so I've not updated it.
Anyone feel free to point out what should be added, and I'll comply.

The new element has the form
<disksnapshot default='value' toggle='off'>
because I'd like to convey two informations:
- disk snapshot is supposed to be here, and it is (default='on')
- disk snapshot is supposed to be here, and is NOT (default='off')

Put in a different way, I tried to help the client as much as
I'm not particolary fond of this format, and I'm really open to
alternatives here. Perhaps a simpler <disksnapshot/> element can
convey the same meaning? Suggestions welcome.

* patches #2, #3
Are trivial and they provide the ground for the last patch which
add a new unit tests. They are just dependencies for it.
I tried to make them less invasive as possible.

* patch #4
add a new unit test, aiming to test not only this new feature
but also the whole XML capabilities test.
I was under the impression that this kind of test do not really
fit into existing one, so I added a new one.
Suggestions about possible improvements for this test are welcome

Francesco Romani (4):
  qemu: export disk snapshot support in capabilities
  qemu: add function to fill capabilities cache
  qemu: export the virQEMUCapsInitGuest function.
  qemu: add unit tests for the capabilities xml

 .gitignore                                         |   1 +
 docs/schemas/capability.rng                        |   6 +
 src/qemu/qemu_capabilities.c                       |  40 +++-
 src/qemu/qemu_capabilities.h                       |   4 +
 tests/Makefile.am                                  |  10 +-
 tests/qemucaps2xmldata/all_1.6.0-1.caps            | 142 ++++++++++++++
 tests/qemucaps2xmldata/all_1.6.0-1.xml             |  51 +++++
 tests/qemucaps2xmldata/nodisksnapshot_1.6.0-1.caps | 141 +++++++++++++
 tests/qemucaps2xmldata/nodisksnapshot_1.6.0-1.xml  |  51 +++++
 tests/qemucaps2xmltest.c                           | 217 +++++++++++++++++++++
 10 files changed, 655 insertions(+), 8 deletions(-)
 create mode 100644 tests/qemucaps2xmldata/all_1.6.0-1.caps
 create mode 100644 tests/qemucaps2xmldata/all_1.6.0-1.xml
 create mode 100644 tests/qemucaps2xmldata/nodisksnapshot_1.6.0-1.caps
 create mode 100644 tests/qemucaps2xmldata/nodisksnapshot_1.6.0-1.xml
 create mode 100644 tests/qemucaps2xmltest.c


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