[PATCH 10/17] meta-isar: deploy-image: Warn if overwriting a non-empty disk

[Jan Kiszka <jan.kiszka@siemens.com>]

From: Jan Kiszka <jan.kiszka@siemens.com>

Check of the first MB of the target device is only containing zero and
warn otherwise before overwriting potentially valuable data. Looking
at the first MB should cover enough partition table and file system
structures to detect a valid disk.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---
 .../deploy-image/files/deploy-image-wic.sh                  | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/meta-isar/recipes-installer/deploy-image/files/deploy-image-wic.sh b/meta-isar/recipes-installer/deploy-image/files/deploy-image-wic.sh
index 09d6cc11..81a006ce 100644
--- a/meta-isar/recipes-installer/deploy-image/files/deploy-image-wic.sh
+++ b/meta-isar/recipes-installer/deploy-image/files/deploy-image-wic.sh
@@ -96,6 +96,12 @@ if ! dialog --yes-label Ok --no-label Cancel \
     exit 0
 fi
 
+if ! cmp /dev/zero "$TARGET_DEVICE" -n 1M && \
+   ! dialog --defaultno \
+            --yesno "WARNING: Target device is not empty! Continue anyway?" 5 60; then
+    exit 0
+fi
+
 bmap_options=""
 if [ -z "$DISK_BMAP" ]; then
     bmap_options="--nobmap"
-- 
2.43.0