This matches the expectation. i.e. we return no-match and we do not
return a scanned print as we don't have anything for it. If we did
indeed return a scanned print, then fprintd would try to delete it
during enroll and would then fail.
Note that we do *not* return a DATA_NOT_FOUND error in the storage
device if the print does not exist. This is because not all devices
support reporting this error. It is therefore more sensible to handle it
gracefully and expect test setups to set the error explicitly for
testing purposes.
The error may not be NULL, as such we need a second variable and then
we'll only forward any error from g_usb_device_release_interface if
there was none before.
We only allow suspending while we are in the interrupt transfer stage.
To suspend, we cancel the interrupt transfer and at resume time we
restart it.
This has been tested to work correctly on an X1 Carbon 8th Gen with
suspend mode set to "Windows 10" (i.e. S0ix [s2idle] and not S3 [suspend
to RAM]). With S3 suspend, the USB root hub appears to be turned off or
reset and the device will be unresponsive afterwards (if it returns). To
avoid issues, libfprint disables the "persist" mode in the kernel and
we'll see a new device instead after resume.
The assumption here is that in most cases, we will just cancel any
ongoing operation. However, if the device choses to implement
suspend/resume handling and it returns success, then operations will not
be cancelled.
Note that suspend/resume requests cannot be cancelled.
Closes: #256
Check if a device is too hot. If it is too hot already, refuse
operation. If it becomes too hot while an operation is ongoing, then
cancel the action and force a FP_DEVICE_ERROR_TOO_HOT return value.
Devices that are considered to never run hot will have FEATURE_ALWAYS_ON
set. If set, the UI can safely assume that it is fine to run fingerprint
authentication in the background without other user interaction.
Closes: #346
This will allow libfprint to cancel operations internally in the future.
If the internal cancellation method is used, then the private
current_cancellation_reason variable must be set to the GError. This
error will be returned when set.
This temperature model has three states:
* COLD
* WARM
* HOT
Device drivers can define the time it requires for the device to get HOT
and COLD. The underlying model assumes an exponential warming and
cooling process and enforces a cool-off time after the device has
reached the HOT state. This cool down period is however shorter than the
specified time in the driver.
The timeout is designed to continue commands automatically that are
common (e.g. opening the device). This doesn't really make sense for
scan commands, and removing the timeout enables test setups where user
interaction with the device may happen at arbitrary times.
One exception is device removal/unplug, in which case the timeout will
be added anyway.
Such an empty identify can be run by fprintd intentionally for duplicate
checking at the start of an enroll operation, which currently runs into
an error from the driver.
Avoid this by simply returning success immediately. This is fine, as
synaptics is only checking the explicitly passed list of prints rather
than using all available prints from the storage.
