[PATCH v1 0/4] Add 'version' to other exported types

[Michal Prívozník]

On 4/5/22 13:43, Victor Toso wrote:
> Hi,
> 
> This series is an extension of what Daniel did in e0e0bf6628 "scripts:
> include function versions in API definition".
> 
> The main motivation behind this is to help code generators to consider
> if a given symbol is present in a given version of libvirt that they are
> either running/building against, more specifically:
> 
>     https://gitlab.com/libvirt/libvirt-go-module/-/merge_requests/7
> 
> As headers are already a great source of documentation for developers,
> I'm suggesting to add a specific comment to each of this exported types:
> 
>     /* ... Since <version> */
> 
> For the use case I mentioned above, I'm adding small parsing function in
> apibuild.py to fetch the above metadata and included it on the generated
> XML API.
> 
> To avoid adding too much noise in the githistory, I'm proposing the
> addition of symbols.versions.allowlist file, that apibuild.py can use to
> fetch the first git tag that a given symbol appeared in. I did a small
> script to generate it, but it sums up to calling the bellow command for
> any tag that starts with 'v' and has not '-rc'.
> 
>     git grep $symbol $tag ./include

This gives you the latest tag that a symbol was touched in. You need to
look at the very first commit that introduced the symbol. For instance,
in your allowlist file you have:

  virConnectDomainEventDeregister v0.10.0

but src/libvirt_public.syms lists this symbol in 0.5.0 release:

LIBVIRT_0.5.0 {
    global:
        ...
        virConnectDomainEventDeregister;

> 
> I'm trying the simples approach I could find but I'm happy to improve
> this further based on your suggestions.
> 
> Ah, the diff in the generated XMLs, per patch (sadly, pasteben drops it
> after a single day). The initial reference is current master 67c77744d7
> 'tests: Fixing compiler warning in cputest'
> 
>  0001 (enums) ... https://paste.centos.org/view/e9137ef0
>  0002 (typedefs)  https://paste.centos.org/view/76f0b397
>  0003 (macros) .. https://paste.centos.org/view/b68fb03a
>  0004 (variables) https://paste.centos.org/view/4a20d9bb
> 
> Cheers,
> Victor
> 
> Victor Toso (4):
>   scripts: apibuild: parse 'Since' version for enums
>   scripts: apibuild: parse 'Since' for typedefs
>   scripts: apibuild: parse 'Since' for macros
>   scripts: apibuild: add 'version' to variables
> 
>  scripts/apibuild.py        |   68 +-
>  symbols.versions.allowlist | 2144 ++++++++++++++++++++++++++++++++++++
>  2 files changed, 2199 insertions(+), 13 deletions(-)
>  create mode 100644 symbols.versions.allowlist
> 

I like this. It's not only for Golang bindings, but other bindings might
benefit from this as well. And also developers reading the docs (they
see immediately what version was the symbol they are looking at
introduced in).

Having said that, maybe we should just add 'Since ...' to every symbol
in include/**\.h instead of having it on a side then? If not, then I
think scripts/ or docs/ is better location for the allowlist file.

Moreover, the allowlist file now contains

Michal