* Add support for batteries outputting Time to empty on linux
The battery in the pinebook pro does not output the remaining charge
in Wh or mAh, so i3 cannot calculate the time remaining. However, it
does directly output the number of minutes remaining on in
POWER_SUPPLY_TIME_TO_EMPTY. This adds support for reading this field
and converting it to seconds_remaining.
* Add testcase for POWER_SUPPLY_TIME_TO_EMTY_NOW
Added a function to print file contents to status bar without newlines.
Added tests for print file contents function
Added manpage entry for file contents
`print_battery_info` computes `batt_info.percentage_remaining` by
dividing batt_info.remaining by `full`. If `full` is `0` then the
battery remaining will be reported as "inf".
Before this, it tries to set `full` to either the design capacity or to
the last known good charge. It determines if these values are available
by checking whether their fields in `batt_info` are non-negative. As it
initialized `batt_info` with values of `-1`, a non-negative value
implies that something has provided a value.
`slurp_all_batteries` and `add_battery_info` however initialize these
fields to zero, so if these functions are called then
`batt_info.full_design` will always be used.
This means that on systems that don't provide a value for design
capacity the percentage remaining will be reported as "inf", unless the
user has set `last_full_capacity` to `true` in their `i3status.conf`.
This patch changes `print_battery_info` to expect values for the battery
capacity to be strictly greater than zero. This seems reasonable as a
battery with a capacity of zero isn't useful.
An alternative solution would be to change `slurp_all_batteries` and
`add_battery_info` to initialize `batt_info` with `-1`, as
`print_battery_info` does. This is less appealing as `add_battery_info`
is accumulating the values, so using `-1` would introduce off-by-one
errors without additional code to avoid them.
This change addresses the issue #199 asking for multiple CPU support. It
takes an arbitrary CPU number and outputs its usage using the same
arithmetics as for CPU aggregation. It currently doesn't support
FreeBSD.