Re: [PATCH v3] base.bbclass: Add support to EXTRA_DISTRO_FEATURES

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Wed, 2013-07-31 at 12:13 -0300, Otavio Salvador wrote:
> This allow the addition and removal of distro features easily. To add
> a feature, use:
> 
>  EXTRA_DISTRO_FEATURES += "wayland"
> 
> and to remove, use '~' prefix, as:
> 
>  EXTRA_DISTRO_FEATURES += "~x11"
> 
> This code has been mostly copied from Mentor Graphics public layer but
> changed the variable name for a more descriptive name. The original
> code can be seen at user_feature.bbclass at:
> 
>  http://git.yoctoproject.org/cgit/cgit.cgi/meta-mentor
> 
> Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
> ---
> Changes for v3:
> - Drop _prepend/_append flags from DISTRO_FEATURES to avoid the re-add
> 
>  meta/classes/base.bbclass |  4 ++++
>  meta/lib/oe/utils.py      | 25 +++++++++++++++++++++++++
>  2 files changed, 29 insertions(+)
> 
> diff --git a/meta/classes/base.bbclass b/meta/classes/base.bbclass
> index 9c92e0b..83f6458 100644
> --- a/meta/classes/base.bbclass
> +++ b/meta/classes/base.bbclass
> @@ -298,6 +298,9 @@ def buildcfg_neededvars(d):
>      if pesteruser:
>          bb.fatal('The following variable(s) were not set: %s\nPlease set them directly, or choose a MACHINE or DISTRO that sets them.' % ', '.join(pesteruser))
>  
> +EXTRA_DISTRO_FEATURES ?= ""
> +EXTRA_DISTRO_FEATURES[type] = "list"
> +
>  addhandler base_eventhandler
>  base_eventhandler[eventmask] = "bb.event.ConfigParsed bb.event.BuildStarted"
>  python base_eventhandler() {
> @@ -307,6 +310,7 @@ python base_eventhandler() {
>          preferred_ml_updates(e.data)
>          oe.utils.features_backfill("DISTRO_FEATURES", e.data)
>          oe.utils.features_backfill("MACHINE_FEATURES", e.data)
> +        oe.utils.extra_distro_features(e.data)
>  
>      if isinstance(e, bb.event.BuildStarted):
>          localdata = bb.data.createCopy(e.data)
> diff --git a/meta/lib/oe/utils.py b/meta/lib/oe/utils.py
> index 82987e8..db468cb 100644
> --- a/meta/lib/oe/utils.py
> +++ b/meta/lib/oe/utils.py
> @@ -117,6 +117,31 @@ def features_backfill(var,d):
>      if addfeatures:
>          d.appendVar(var, " " + " ".join(addfeatures))
>  
> +def extra_distro_features(d):
> +    import oe.data
> +
> +    l = d.createCopy()
> +    l.finalize()
> +
> +    extra_features = oe.data.typed_value('EXTRA_DISTRO_FEATURES', l)
> +    if not extra_features:
> +        return
> +
> +    distro_features = l.getVar('DISTRO_FEATURES', True).split()
> +    for feature in extra_features:
> +        if feature.startswith('~'):
> +            feature = feature[1:]
> +            if feature in distro_features:
> +                distro_features.remove(feature)
> +        else:
> +            if feature not in distro_features:
> +                distro_features.append(feature)
> +
> +    # Avoid readding the removed features later
> +    d.delVarFlag("DISTRO_FEATURES", "_append")
> +    d.delVarFlag("DISTRO_FEATURES", "_prepend")

I quite clearly said this was a hack to allow you to see what the
problem was with the code and that it was *not* an acceptable change to
go into the core. I don't see any mention of that now and that is a
little frustrating to see this being proposed as a patch.

Cheers,

Richard