The LWPCookieJar can be saved on 64-bit Ubuntu, but not on 32-bit Ubuntu
when the expiration year is greater than 2038.  This has not been tested
on any other Intel-compatible Linux platform, though it appears related
to the Year 2038 bug.  The MozillaCookieJar does not have a problem
saving on either architecture.

A sample crash is shown below:

  File "/home/user/xblstatus/LiveConnect.py", line 189, in connect
    self.cookiejar.save(self.cookieFile)
  File "/usr/lib/python2.5/_LWPCookieJar.py", line 89, in save
    f.write(self.as_lwp_str(ignore_discard, ignore_expires))
  File "/usr/lib/python2.5/_LWPCookieJar.py", line 75, in as_lwp_str
    r.append("Set-Cookie3: %s" % lwp_cookie_str(cookie))
  File "/usr/lib/python2.5/_LWPCookieJar.py", line 35, in lwp_cookie_str
    time2isoz(float(cookie.expires))))
  File "/usr/lib/python2.5/cookielib.py", line 98, in time2isoz
    year, mon, mday, hour, min, sec = time.gmtime(t)[:6]
ValueError: timestamp out of range for platform time_t

---

The cookie jar and urllib2 integration was done with:

self.cookiejar = cookielib.LWPCookieJar()

self.opener =
urllib2.build_opener(urllib2.HTTPCookieProcessor(self.cookiejar))

urllib2.install_opener(self.opener)

---

The code used to save the cookie after accessing the web page was:

self.cookiejar.save(self.cookieFile)

The cookieFile variable is simply the default location of the cookie
file for saving in the program.

Shouldn't module time be changed to use a cross-platform implementation that uses a 64 bit time_t-like type?  Apparently Perl 6 has made the equivalent change.

Admittedly there seems to be no sign of that actually happening.

> Shouldn't module time be changed to use a cross-platform implementation
> that uses a 64 bit time_t-like type? Apparently Perl 6 has made the
> equivalent change.

The error occurs on time.gmtime(t): even if we use 64 bits time_t type, we have to downcast it to system time_t later, because we would like to call gmtime() function at the end.

To workaround gmtime() limitation: we can simply use datetime instead. Attached patch replaces gmtime() by datetime.utcfromtimestamp(), and use its .strftime() method which has no such limitation.

Oh, my patch is incomplete: time2netscape() has the same issue.

Victor,

I don't see your patch.  Did you remove it?

No, I forgot to upload it...

While it is unlikely that a purely numeric format such as "%Y-%m-%d
%H:%M:%S" will be locale dependent, it is possible that some pre-C99
systems would format dates using exotic digits is some locales.  Given
that format is so simple, I would just use explicit formatting of dt
components instead of datetime.strftime.  Doing so will also eliminate
a call to system strftime which is known to be quirky on popular
platforms even in C locale.

If datetime.strftime() is not reliable, we should maybe fix it instead of using a workaround?

On Fri, Feb 18, 2011 at 11:04 AM, STINNER Victor <report@bugs.python.org> wrote:
..
> If datetime.strftime() is not reliable, we should maybe fix it instead of using a workaround?

The real fix would be to rewrite strftime so that it does not call
system strftime.  See issue3173.

New changeset b15f60f9e256 by Victor Stinner in branch '3.1':
Issue #5537: Fix time2isoz() and time2netscape() functions of httplib.cookiejar
http://hg.python.org/cpython/rev/b15f60f9e256

> While it is unlikely that a purely numeric format such as "%Y-%m-%d
> %H:%M:%S" will be locale dependent, it is possible that some pre-C99
> systems would format dates using exotic digits is some locales.

Ok, I rewrote my patch to avoid strftime(). It should now be fixed.

FYI datetime.fromtimestamp() converts the timestamp to a double, which has a precision of 53 bits (no precision loss for year < 285,422,890 and so it's enough for year 2038).

This bug still exists in Python 2.7.3 32-bit on Linux.

I wonder if this might be because the patch (posted 2011-02-18) used utcfromtimestamp().  datetime.datetime.utcfromtimestamp(2**32) will fail on 32-bit systems.

The bug does NOT exist in Python 2.7.3 32-bit on Windows (64-bit OS).

==========================================
32-BIT PYTHON ON 32-BIT LINUX
------------------------------------------
$ python -c "import sys, cookielib; print sys.version; print cookielib.time2isoz(2322923767)"
2.7.3 (default, Apr 10 2013, 05:46:21) 
[GCC 4.6.3]
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python2.7/cookielib.py", line 99, in time2isoz
    year, mon, mday, hour, min, sec = time.gmtime(t)[:6]
ValueError: timestamp out of range for platform time_t
==========================================


==========================================
64-BIT PYTHON ON 64-BIT LINUX
------------------------------------------
$ python -c "import sys, cookielib; print sys.version; print cookielib.time2isoz(2322923767)"
2.7.3 (default, Aug  3 2012, 17:21:07)
[GCC 4.1.2 20080704 (Red Hat 4.1.2-52)]
2043-08-11 16:36:07Z
==========================================


==========================================
32-BIT PYTHON ON 64-BIT WINDOWS
------------------------------------------
C:\>python -c "import sys, cookielib; print sys.version; print cookielib.time2isoz(2322923767)"
2.7.3 (default, Apr 10 2012, 23:31:26) [MSC v.1500 32 bit (Intel)]
2043-08-11 16:36:07Z
==========================================

For those who are affected by this bug, here's a snippet to monkey-patch cookielib on any Python 2.4 to 2.7.

A more complete version of this was attached to my message a moment ago.

==========================================
import cookielib
try:
    cookielib.time2isoz(2**32)
except ValueError:
    from datetime import datetime, timedelta
    def time2isoz(t=None):
        if t is None:
            dt = datetime.now()
        else:
            dt = datetime.utcfromtimestamp(0) + timedelta(seconds=int(t))
        return "%04d-%02d-%02d %02d:%02d:%02dZ"%\
                (dt.year, dt.month, dt.day, dt.hour, dt.minute, dt.second)
    cookielib.time2isoz = time2isoz
==========================================