Squashed 'yocto-poky/' content from commit ea562de

git-subtree-dir: yocto-poky
git-subtree-split: ea562de57590c966cd5a75fda8defecd397e6436
diff --git a/meta/classes/distro_features_check.bbclass b/meta/classes/distro_features_check.bbclass
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+# Allow checking of required and conflicting DISTRO_FEATURES
+#
+# ANY_OF_DISTRO_FEATURES:   ensure at least one item on this list is included
+#                           in DISTRO_FEATURES.
+# REQUIRED_DISTRO_FEATURES: ensure every item on this list is included
+#                           in DISTRO_FEATURES.
+# CONFLICT_DISTRO_FEATURES: ensure no item in this list is included in
+#                           DISTRO_FEATURES.
+#
+# Copyright 2013 (C) O.S. Systems Software LTDA.
+
+python () {
+    # Assume at least one var is set.
+    distro_features = (d.getVar('DISTRO_FEATURES', True) or "").split()
+
+    any_of_distro_features = d.getVar('ANY_OF_DISTRO_FEATURES', True)
+    if any_of_distro_features:
+        any_of_distro_features = any_of_distro_features.split()
+        if set.isdisjoint(set(any_of_distro_features),set(distro_features)):
+            raise bb.parse.SkipPackage("one of '%s' needs to be in DISTRO_FEATURES" % any_of_distro_features)
+
+    required_distro_features = d.getVar('REQUIRED_DISTRO_FEATURES', True)
+    if required_distro_features:
+        required_distro_features = required_distro_features.split()
+        for f in required_distro_features:
+            if f in distro_features:
+                continue
+            else:
+                raise bb.parse.SkipPackage("missing required distro feature '%s' (not in DISTRO_FEATURES)" % f)
+
+    conflict_distro_features = d.getVar('CONFLICT_DISTRO_FEATURES', True)
+    if conflict_distro_features:
+        conflict_distro_features = conflict_distro_features.split()
+        for f in conflict_distro_features:
+            if f in distro_features:
+                raise bb.parse.SkipPackage("conflicting distro feature '%s' (in DISTRO_FEATURES)" % f)
+}