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"""unwrap_timestamp
The unwrap_timestamp module contains tools to unwrap timestamp values.
"""
# IMPORT
from blue_st_sdk.utils.python_utils import synchronized
# CLASSES
[docs]class UnwrapTimestamp(object):
"""Class that unwraps a timestamp."""
_NEAR_TO_END_TH = (1 << 16) - 100
"""Threshold."""
[docs] def __init__(self):
"""Constructor."""
# Number of times the timestamp has reset.
# The timestamp is reset whenever the received timestamp has a value
# greater than "2^16 - 100" and it is followed by a package with a
# smaller value.
self._reset_times = 0
# Last raw timestamp received.
# It is a number between "0" and "2^16-1".
self._last_timestamp = 0
[docs] @synchronized
def unwrap(self, timestamp):
"""Add a multiple of (1 << 16) to the timestamp to reset it, if needed.
Args:
timestamp (int): Timestamp.
Returns:
int: The unwrapped timestamp.
"""
if self._last_timestamp > self._NEAR_TO_END_TH \
and self._last_timestamp > timestamp:
self._reset_times += 1
self._last_timestamp = timestamp
#return long(self._reset_times) * (1 << 16) + long(timestamp) #Python 2
return int(self._reset_times) * (1 << 16) + int(timestamp) #Python 3