In the future we'll want to use this flag to signify if the release is an
upgrade, downgrade, below the version-lowest, or if it is locked in some way.
The libxmlb library is much faster to query, and does not require the daemon
to parse the XML metadata at startup. It's a zero-copy mmap design that is more
modern and less clunky.
RSS has reduced from 3Mb (peak 3.61Mb) to 1Mb (peak 1.07Mb) and the startup
time has gone from 280ms to 250ms.
When using failed to open firmware.cab we pass in a device ID of '*' which
tells the daemon to update anything that matches. The current implementation
will fail in two ways:
* If duplicate hardware is installed (for instance two Unifying receivers) then
only the first matching device will be updated.
* If the firmware archive contains two different images then we only try and
upgrade the first device that matches. This means we're unable to update
composite devices using one firmware file.
To fix both issues, carefully build a list of tasks that can be processed using
the given firmware and installed devices, request authentication using all the
different action IDs, then upgrade all the devices one-at-a-time.
Based on a patch by Mario Limonciello <mario.limonciello@dell.com>, many thanks.
