sanity-meta-virt.bbclass: add class for bbappend files checking

Add a new class, sanity-meta-virt.bbclass, to check for whether necessary
settings are available for bbappend files in this layer to be effective,
and warn users if not.

In addition, a variable SKIP_SANITY_BBAPPEND_CHECK is added to enable users
to explicitly skip the checking to avoid unwanted warnings.

Signed-off-by: Chen Qi <Qi.Chen@windriver.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>

2 files changed, 14 insertions, 0 deletions

diff --git a/classes/sanity-meta-virt.bbclass b/classes/sanity-meta-virt.bbclass
new file mode 100644
index 00000000..bd2b7172
--- /dev/null
+++ b/classes/sanity-meta-virt.bbclass
@@ -0,0 +1,10 @@
+addhandler virt_bbappend_distrocheck
+virt_bbappend_distrocheck[eventmask] = "bb.event.ConfigParsed"
+python virt_bbappend_distrocheck() {
+    skip_check = e.data.getVar('SKIP_SANITY_BBAPPEND_CHECK') == "1"
+    if 'virtualization' not in e.data.getVar('DISTRO_FEATURES').split() and not skip_check:
+        bb.warn("You have included the meta-virtualization layer, but \
+'virtualization' has not been enabled in your DISTRO_FEATURES. Some bbappend files \
+may not take effect. See the meta-virtualization README for details on enabling \
+virtualization support.")
+}
diff --git a/conf/layer.conf b/conf/layer.conf
index be08a985..51ca8ee2 100644
--- a/conf/layer.conf
+++ b/conf/layer.conf
@@ -22,3 +22,7 @@ require conf/distro/include/virt_security_flags.inc
 
 PREFERRED_PROVIDER_virtual/runc ?= "runc-docker"
 PREFERRED_PROVIDER_virtual/containerd ?= "containerd-docker"
+
+# Sanity check for meta-virtualization layer.
+# Setting SKIP_SANITY_BBAPPEND_CHECK to "1" would skip the bbappend files check.
+INHERIT += "sanity-meta-virt"