def clear_time_state(self):
""" clear_time_state
Clears the time state so that the clock can be adjusted manually again.
return: None
"""
adjtimex.adjtimex(
adjtimex.Timex(modes=adjtimex.ADJ_STATUS, status=adjtimex.STA_PLL))
adjtimex.adjtimex(adjtimex.Timex(modes=adjtimex.ADJ_STATUS))
def get_speed(self):
""" get_speed
Gets the current system clock speed. Can be used to provide to set_speed after a reboot.
return: Speed of system clock, close to 1.0.
"""
timeadj = adjtimex.Timex(modes=0)
adjtimex.adjtimex(timeadj)
speed = float(timeadj.tick) / 10000 + float(timeadj.freq) / SEC_TO_FREQ
return speed
def set_offset(self, offset=0.0):
""" set_offset
Passes the offset to the kernel, making the actual time PLL work.
@param offset: Time offset in (actual_time - system_time), as passed to the kernel
return: None
"""
offset_us = int(offset * 1000000)
timeadj = adjtimex.Timex(modes=adjtimex.ADJ_OFFSET
| adjtimex.ADJ_STATUS | adjtimex.ADJ_MICRO
| adjtimex.ADJ_MAXERROR,
offset=offset_us,
maxerror=abs(offset_us),
status=adjtimex.STA_PLL)
adjtimex.adjtimex(timeadj)
def set_speed(self, factor=1.0):
""" set_speed
Sets the system frequency, obtained using get_speed.
@param factor : Speed of system clock, should be close to 1.0
return: None
"""
# Tick is always positive, we can round by adding 0.5
tick = int(factor * 10000 + 0.5)
remainder = factor - (tick / 10000.0)
freq = int(round(remainder * SEC_TO_FREQ))
timeadj = adjtimex.Timex(modes=adjtimex.ADJ_FREQUENCY
| adjtimex.ADJ_TICK | adjtimex.ADJ_STATUS,
freq=freq,
tick=tick,
status=adjtimex.STA_PLL)
adjtimex.adjtimex(timeadj)
def timestep(self, seconds=0.0):
""" timestep
Makes a timestep using the provided seconds. Time will be added
to the system time so a positive value will make the clock go forward.
@param seconds: Number of seconds to adjust the system clock
return: None
"""
microseconds = int(round(seconds * 1000000))
seconds_int = int(microseconds // 1000000)
usec = int(microseconds - (seconds_int * 1000000))
timeval = adjtimex.Timeval(seconds_int, usec)
timeadj = adjtimex.Timex(modes=adjtimex.ADJ_SETOFFSET
| adjtimex.ADJ_MICRO,
time=timeval)
adjtimex.adjtimex(timeadj)