tree ea65de7e24d804c25d423abe5e511aadfffec864
parent 2c1f4d33eb125bd8aed06d40915124c810d3c57d
author Manojkiran Eda <manojkiran.eda@gmail.com> 1783327951 +0530
committer ManojKiran Eda <manojkiran.eda@gmail.com> 1788416501 +0000

bios: On DBus failure fall back to persisted value

When building the BIOS attribute/value tables at startup,
buildAndStoreAttrTables() reads the BaseBIOSTable property from
bios-settings-manager and passes the stored currentValue to each
attribute's constructEntry() as optAttributeValue.

For attributes backed by a D-Bus property (dBusMap is set), the live
D-Bus value is the ground truth and should be preferred.  However, if
the D-Bus read fails (e.g. the object has not yet appeared on the bus),
the correct fallback is the last known persisted value from
BaseBIOSTable.

Fix all three attribute types (integer, string, enum) by adding an
optional persisted value into the getAttrValue() / getAttrValueIndex()
helpers.  The priority order is now:

  1. Live D-Bus value   (when dBusMap is set and the read succeeds)
  2. Persisted value    (optAttributeValue from BaseBIOSTable)
  3. JSON default       (last resort)

Non-D-Bus attributes (no dBusMap) follow the same priority 2 & 3 path
they always did.

Change-Id: I4c1f52bbd47712846b59e0b25619369b4e0f4a6d
Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>