[PATCH 2/4] buildstats: Fix bbclass to work with ISAR

[Uladzimir Bely <ubely@ilbers.de>]

1. rootfs may be empty that causes exception.
2. sudo required to calculate rootfs disk usage.
3. sys.path modification to make meta/lib available.

Signed-off-by: Uladzimir Bely <ubely@ilbers.de>
---
 meta/classes/buildstats.bbclass | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/meta/classes/buildstats.bbclass b/meta/classes/buildstats.bbclass
index 0de6052..e2db8f6 100644
--- a/meta/classes/buildstats.bbclass
+++ b/meta/classes/buildstats.bbclass
@@ -242,9 +242,9 @@ python run_buildstats () {
             bs = os.path.join(bsdir, "build_stats")
             with open(bs, "a") as f:
                 rootfs = d.getVar('IMAGE_ROOTFS')
-                if os.path.isdir(rootfs):
+                if rootfs and os.path.isdir(rootfs):
                     try:
-                        rootfs_size = subprocess.check_output(["du", "-sh", rootfs],
+                        rootfs_size = subprocess.check_output(["sudo", "du", "-sh", rootfs],
                                 stderr=subprocess.STDOUT).decode('utf-8')
                         f.write("Uncompressed Rootfs size: %s" % rootfs_size)
                     except subprocess.CalledProcessError as err:
@@ -270,6 +270,9 @@ addhandler run_buildstats
 run_buildstats[eventmask] = "bb.event.BuildStarted bb.event.BuildCompleted bb.event.HeartbeatEvent bb.build.TaskStarted bb.build.TaskSucceeded bb.build.TaskFailed"
 
 python runqueue_stats () {
+    import sys
+    oe_lib_path = os.path.join(d.getVar('LAYERDIR_core'), 'lib')
+    sys.path.insert(0, oe_lib_path)
     import buildstats
     from bb import event, runqueue
     # We should not record any samples before the first task has started,
-- 
2.20.1