Formatting dates sometimes returns January zeroth

[creideiki]

I had some weird errors processing CSV output from psort, and tracked them down to a couple of lines having date stamps of "01/00/1971" or "01/00/1974", which seems wrong. Outputting JSON from psort instead, I got the timestamps in POSIX format, and tracked the error to dfdatetime.

The original error occurred on an up-to-date Fedora 29, running plaso-20181219-3 out of LiFTeR on Python 2.7.15, but the error is still there when running the current master of dfdatetime (0b23e03).

$ python2
>>> from dfdatetime import posix_time as dfdatetime_posix_time
>>> dfdatetime_posix_time.PosixTime(31511228).CopyToDateTimeString()
u'1971-01-00 17:07:08'
>>> dfdatetime_posix_time.PosixTime(126189827).CopyToDateTimeString()
u'1974-01-00 12:43:47'

The same bug is present in the PosixTimeInMilliseconds() and PosixTimeInMicroseconds() interfaces (which is what psort actually uses).

date says those timestamps were on the 31:st of December the year before, not the zeroth of January:

$ env LC_TIME=en_US TZ=UTC date --date='@31511228'
Thu Dec 31 17:07:08 UTC 1970
$ env LC_TIME=en_US TZ=UTC date --date='@126189827'
Mon Dec 31 12:43:47 UTC 1973

[joachimmetz]

Thx for the report I'll have a look as soon time permits

[joachimmetz]

Issue is that interface._GetDateValues does not correctly handle number of days (in year) of 0.

Pending fixes: #135

With fix:

In [2]: from dfdatetime import posix_time

In [3]: posix_time.PosixTime(31511228).CopyToDateTimeString()
Out[3]: u'1970-12-31 17:07:08'

In [4]: posix_time.PosixTime(126189827).CopyToDateTimeString()
Out[4]: u'1973-12-31 12:43:47'

[joachimmetz]

Changes merged and new pre-release made available.

[creideiki]

Thanks! I just tried the 20190116 release on my real data, and it solves the problem.