import os import pytz import re import warnings from tzlocal import utils _cache_tz = None def _tz_from_env(tzenv): if tzenv[0] == ':': tzenv = tzenv[1:] # TZ specifies a file if os.path.isabs(tzenv) and os.path.exists(tzenv): with open(tzenv, 'rb') as tzfile: return pytz.tzfile.build_tzinfo('local', tzfile) # TZ specifies a zoneinfo zone. try: tz = pytz.timezone(tzenv) # That worked, so we return this: return tz except pytz.UnknownTimeZoneError: raise pytz.UnknownTimeZoneError( "tzlocal() does not support non-zoneinfo timezones like %s. \n" "Please use a timezone in the form of Continent/City") def _try_tz_from_env(): tzenv = os.environ.get('TZ') if tzenv: try: return _tz_from_env(tzenv) except pytz.UnknownTimeZoneError: pass def _get_localzone(_root='/'): """Tries to find the local timezone configuration. This method prefers finding the timezone name and passing that to pytz, over passing in the localtime file, as in the later case the zoneinfo name is unknown. The parameter _root makes the function look for files like /etc/localtime beneath the _root directory. This is primarily used by the tests. In normal usage you call the function without parameters.""" tzenv = _try_tz_from_env() if tzenv: return tzenv # Are we under Termux on Android? if os.path.exists('/system/bin/getprop'): import subprocess androidtz = subprocess.check_output(['getprop', 'persist.sys.timezone']).strip().decode() return pytz.timezone(androidtz) # Now look for distribution specific configuration files # that contain the timezone name. for configfile in ('etc/timezone', 'var/db/zoneinfo'): tzpath = os.path.join(_root, configfile) try: with open(tzpath, 'rb') as tzfile: data = tzfile.read() # Issue #3 was that /etc/timezone was a zoneinfo file. # That's a misconfiguration, but we need to handle it gracefully: if data[:5] == b'TZif2': continue etctz = data.strip().decode() if not etctz: # Empty file, skip continue for etctz in data.decode().splitlines(): # Get rid of host definitions and comments: if ' ' in etctz: etctz, dummy = etctz.split(' ', 1) if '#' in etctz: etctz, dummy = etctz.split('#', 1) if not etctz: continue tz = pytz.timezone(etctz.replace(' ', '_')) if _root == '/': # We are using a file in etc to name the timezone. # Verify that the timezone specified there is actually used: utils.assert_tz_offset(tz) return tz except IOError: # File doesn't exist or is a directory continue # CentOS has a ZONE setting in /etc/sysconfig/clock, # OpenSUSE has a TIMEZONE setting in /etc/sysconfig/clock and # Gentoo has a TIMEZONE setting in /etc/conf.d/clock # We look through these files for a timezone: zone_re = re.compile(r'\s*ZONE\s*=\s*\"') timezone_re = re.compile(r'\s*TIMEZONE\s*=\s*\"') end_re = re.compile('\"') for filename in ('etc/sysconfig/clock', 'etc/conf.d/clock'): tzpath = os.path.join(_root, filename) try: with open(tzpath, 'rt') as tzfile: data = tzfile.readlines() for line in data: # Look for the ZONE= setting. match = zone_re.match(line) if match is None: # No ZONE= setting. Look for the TIMEZONE= setting. match = timezone_re.match(line) if match is not None: # Some setting existed line = line[match.end():] etctz = line[:end_re.search(line).start()] # We found a timezone tz = pytz.timezone(etctz.replace(' ', '_')) if _root == '/': # We are using a file in etc to name the timezone. # Verify that the timezone specified there is actually used: utils.assert_tz_offset(tz) return tz except IOError: # File doesn't exist or is a directory continue # systemd distributions use symlinks that include the zone name, # see manpage of localtime(5) and timedatectl(1) tzpath = os.path.join(_root, 'etc/localtime') if os.path.exists(tzpath) and os.path.islink(tzpath): tzpath = os.path.realpath(tzpath) start = tzpath.find("/")+1 while start != 0: tzpath = tzpath[start:] try: return pytz.timezone(tzpath) except pytz.UnknownTimeZoneError: pass start = tzpath.find("/")+1 # No explicit setting existed. Use localtime for filename in ('etc/localtime', 'usr/local/etc/localtime'): tzpath = os.path.join(_root, filename) if not os.path.exists(tzpath): continue with open(tzpath, 'rb') as tzfile: return pytz.tzfile.build_tzinfo('local', tzfile) warnings.warn('Can not find any timezone configuration, defaulting to UTC.') return pytz.utc def get_localzone(): """Get the computers configured local timezone, if any.""" global _cache_tz if _cache_tz is None: _cache_tz = _get_localzone() return _cache_tz def reload_localzone(): """Reload the cached localzone. You need to call this if the timezone has changed.""" global _cache_tz _cache_tz = _get_localzone() return _cache_tz