[libvirt] [PATCH v2 00/16] domcaps: use virTristateBool

v1 posting: https://www.redhat.com/archives/libvir-list/2019-February/msg01088.html v2 changes: - Rebase to master - Remove the full.xml test in patch #3 - Add virCapsEnum 'format' and use it - Extend docs to explain optional XML v1 cover letter: Extending domaincapabilities with new XML schema is currently a bit of a maintenance pain. Consider the case of adding a new enum for listing <sound> models. I want to output this info for the qemu driver. Internally in the domaincapabilities plumbing, whether a <device> is supported= is tracked with boolean true/false. If I extend that pattern for <sound> devices and fill in data for the qemu driver, the other domcaps implementations will now automatically output a new XML element: <sound supported='no'> Now, for bhyve I can 'git grep' confirm that it doesn't have any <sound> support, but for xen/libxl it _is_ supported. So if I don't fill in accurate support in the xen driver, I've just made their domcaps report blatantly incorrect info. Ideally I would make these <sound> changes and the other drivers output would _not_ change. xen output would now be incomplete, but not obviously wrong, which is easier on me the developer, and safer for the API consumer. This moves domcaps plumbing in that direction. It switches most internal 'supported' fields to virTristateBool so we can track an ABSENT state and map that to outputting no XML. Explicit supported='no' values are filled in where needed to ensure existing driver XML doesn't change. cpu and sev supported= values are left unconverted, but they require semi-special handling anyways so aren't really affected by the problem I laid out above. In v2, I additionally added a mechanism to make <enum> values optionally formatted. Right now whenever a new <enum> is added, if the parent bit is supported (like <disk supported='yes'/>), the new <enum> is automatically formatted as well. This has the same problem described above with the @supported bit. Now drivers are required to set a virCapsPtr.report = true if they want the <enum> to be formatted. Existing drives have this value filled in to maintain back compat. Again, bhyve changes are untested. If someone can give them a spin that would be appreciated, otherwise I will try to get a freebsd build setup. Cole Robinson (16): tests: domcaps: Add a default 'empty' test tests: domcaps: Remove unused typedef tests: domcaps: Remove 'full' test conf: domcaps: Add single line formatting macro conf: domcaps: use virTristateBool for 'supported' qemu: domcaps: fill in explicit supported BOOL_NO libxl: domcaps: fill in explicit supported BOOL_NO bhyve: domcaps: fill in explicit supported BOOL_NO schemas: domcaps: Make more elements optional conf: domcaps: Don't output XML on tristate ABSENT conf: domcaps: Add virCapsEnum 'report' qemu: fill in virCapsEnum 'report' libxl: fill in virCapsEnum 'report' bhyve: fill in virCapsEnum 'report' conf: domcaps: Don't format XML on report=false docs: formatdomaincaps: Describe optional XML changes docs/formatdomaincaps.html.in | 11 +++ docs/schemas/domaincaps.rng | 20 ++++- src/bhyve/bhyve_capabilities.c | 27 ++++-- src/conf/domain_capabilities.c | 31 ++++--- src/conf/domain_capabilities.h | 21 ++--- src/libxl/libxl_capabilities.c | 31 +++++-- src/qemu/qemu_capabilities.c | 41 ++++++--- tests/domaincapsschemadata/empty.xml | 16 ++++ tests/domaincapsschemadata/full.xml | 123 --------------------------- tests/domaincapstest.c | 79 +---------------- 10 files changed, 155 insertions(+), 245 deletions(-) create mode 100644 tests/domaincapsschemadata/empty.xml delete mode 100644 tests/domaincapsschemadata/full.xml -- 2.20.1