[OE-core] [PATCH v2 1/1] classes/whitelist: add class to allow whitelisting recipes from a layer

[Paul Eggleton]

Allow restricting recipes brought from a layer to a specified list. This
is similar in operation to blacklist.bbclass, but instead specifies a
per-layer whitelist of recipes (matched by PN or BPN) that are able to
be built from the layer - anything else is skipped. This is potentially
useful where you want to bring in a select set of recipes from a larger
layer e.g. meta-oe.

Implements [YOCTO #8150].

Signed-off-by: Paul Eggleton <paul.eggleton at linux.intel.com>
---
 meta/classes/whitelist.bbclass | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)
 create mode 100644 meta/classes/whitelist.bbclass

diff --git a/meta/classes/whitelist.bbclass b/meta/classes/whitelist.bbclass
new file mode 100644
index 0000000..ab6ac73
--- /dev/null
+++ b/meta/classes/whitelist.bbclass
@@ -0,0 +1,34 @@
+# Class that allows you to restrict the recipes brought from a layer to
+# a specified list. This is similar in operation to blacklist.bbclass
+# but note the difference in how PNWHITELIST is set - we don't use varflags
+# here, the recipe name goes in the value and we use an override for the
+# layer name (although this is not strictly required - you can have one
+# PNWHITELIST value shared by all of the layers specified in
+# PNWHITELIST_LAYERS). The layer name used here is actually the name that
+# gets added to BBFILE_COLLECTIONS in the layer's layer.conf, which may
+# differ from how the layer is otherwise known - e.g. meta-oe uses
+# "openembedded-layer".
+#
+# INHERIT += "whitelist"
+# PNWHITELIST_LAYERS = "layername"
+# PNWHITELIST_layername = "recipe1 recipe2"
+#
+# If you would prefer to set a reason message other than the default, you
+# can do so:
+#
+# PNWHITELIST_REASON_layername = "not supported by ${DISTRO}"
+
+python() {
+    layer = bb.utils.get_file_layer(d.getVar('FILE', True), d)
+    if layer:
+        layers = (d.getVar('PNWHITELIST_LAYERS', True) or '').split()
+        if layer in layers:
+            localdata = bb.data.createCopy(d)
+            localdata.setVar('OVERRIDES', layer)
+            whitelist = (localdata.getVar('PNWHITELIST', True) or '').split()
+            if not (d.getVar('PN', True) in whitelist or d.getVar('BPN', True) in whitelist):
+                reason = localdata.getVar('PNWHITELIST_REASON', True)
+                if not reason:
+                    reason = 'not in PNWHITELIST for layer %s' % layer
+                raise bb.parse.SkipRecipe(reason)
+}
-- 
2.1.0