openstack/deb-python-cassandra-driver
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cython: emulate cpython rounding for datetime deserialization

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PYTHON-480
This commit is contained in:
Adam Holmberg
2016-03-23 15:12:57 -05:00
parent ab2a978665
commit ef5edd0ba5
1 changed files with 14 additions and 1 deletions
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15
cassandra/cython_utils.pyx
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@@ -17,6 +17,8 @@ Duplicate module of util.py, with some accelerated functions
used for deserialization.
"""
from libc.math cimport modf, round, fabs
from cpython.datetime cimport (
timedelta_new,
# cdef inline object timedelta_new(int days, int seconds, int useconds)
@@ -44,6 +46,17 @@ cdef datetime_from_timestamp(double timestamp):
cdef int days = <int> (timestamp / DAY_IN_SECONDS)
cdef int64_t days_in_seconds = (<int64_t> days) * DAY_IN_SECONDS
cdef int seconds = <int> (timestamp - days_in_seconds)
cdef int microseconds = <int> ((timestamp - days_in_seconds - seconds) * 1000000)
cdef double tmp
cdef double micros_left = modf(timestamp, &tmp) * 1000000.
micros_left = modf(micros_left, &tmp)
cdef int microseconds = <int> tmp
# rounding to emulate fp math in delta_new
cdef int x_odd
tmp = round(micros_left)
if fabs(tmp - micros_left) == 0.5:
x_odd = microseconds & 1
tmp = 2.0 * round((micros_left + x_odd) * 0.5) - x_odd
microseconds += <int>tmp
return DATETIME_EPOC + timedelta_new(days, seconds, microseconds)