CasperSecurity
try:
import _winreg as winreg
except ImportError:
try:
import winreg
except ImportError:
winreg = None
from babel.core import get_global
import pytz
# When building the cldr data on windows this module gets imported.
# Because at that point there is no global.dat yet this call will
# fail. We want to catch it down in that case then and just assume
# the mapping was empty.
try:
tz_names = get_global('windows_zone_mapping')
except RuntimeError:
tz_names = {}
def valuestodict(key):
"""Convert a registry key's values to a dictionary."""
dict = {}
size = winreg.QueryInfoKey(key)[1]
for i in range(size):
data = winreg.EnumValue(key, i)
dict[data[0]] = data[1]
return dict
def get_localzone_name():
# Windows is special. It has unique time zone names (in several
# meanings of the word) available, but unfortunately, they can be
# translated to the language of the operating system, so we need to
# do a backwards lookup, by going through all time zones and see which
# one matches.
handle = winreg.ConnectRegistry(None, winreg.HKEY_LOCAL_MACHINE)
TZLOCALKEYNAME = r'SYSTEM\CurrentControlSet\Control\TimeZoneInformation'
localtz = winreg.OpenKey(handle, TZLOCALKEYNAME)
keyvalues = valuestodict(localtz)
localtz.Close()
if 'TimeZoneKeyName' in keyvalues:
# Windows 7 (and Vista?)
# For some reason this returns a string with loads of NUL bytes at
# least on some systems. I don't know if this is a bug somewhere, I
# just work around it.
tzkeyname = keyvalues['TimeZoneKeyName'].split('\x00', 1)[0]
else:
# Windows 2000 or XP
# This is the localized name:
tzwin = keyvalues['StandardName']
# Open the list of timezones to look up the real name:
TZKEYNAME = r'SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones'
tzkey = winreg.OpenKey(handle, TZKEYNAME)
# Now, match this value to Time Zone information
tzkeyname = None
for i in range(winreg.QueryInfoKey(tzkey)[0]):
subkey = winreg.EnumKey(tzkey, i)
sub = winreg.OpenKey(tzkey, subkey)
data = valuestodict(sub)
sub.Close()
if data.get('Std', None) == tzwin:
tzkeyname = subkey
break
tzkey.Close()
handle.Close()
if tzkeyname is None:
raise LookupError('Can not find Windows timezone configuration')
timezone = tz_names.get(tzkeyname)
if timezone is None:
# Nope, that didn't work. Try adding 'Standard Time',
# it seems to work a lot of times:
timezone = tz_names.get(tzkeyname + ' Standard Time')
# Return what we have.
if timezone is None:
raise pytz.UnknownTimeZoneError('Can not find timezone ' + tzkeyname)
return timezone
def _get_localzone():
if winreg is None:
raise pytz.UnknownTimeZoneError(
'Runtime support not available')
return pytz.timezone(get_localzone_name())