Detailed Description

Useful to write and reproduce tests that depend on specific time factors. This API allows to fake the timespec provided by clock_gettime() by using a small shim osmo_clock_gettime().
Choose the clock you want to override, for instance CLOCK_MONOTONIC.
If the clock override is disabled (default) for a given clock, osmo_clock_gettime() will do the same as regular clock_gettime().
If you want osmo_clock_gettime() to provide a specific time, you must enable time override with osmo_clock_override_enable(), then set a pointer to the timespec storing the fake time for that specific clock (struct timespec *ts = osmo_clock_override_gettimespec()) and set it as desired. Next time osmo_clock_gettime() is called, it will return the values previously set through the ts pointer.
A helper osmo_clock_override_add() is provided to increment a given overriden clock with a specific amount of time.