#! /usr/bin/python3
import os
import re
import sys
_defaults = None
_old_versions = None
_unsupported_versions = None
_supported_versions = ["python%s" % ver.strip() for ver in
os.environ.get('DEBPYTHON3_SUPPORTED', '').split(',')
if ver.strip()]
#_default_version = "python%s" % os.environ.get('DEBPYTHON3_DEFAULT', '')
#if _default_version == 'python':
# _default_version = None
_default_version = None
def read_default(name=None):
global _defaults
from configparser import ConfigParser, NoOptionError
if not _defaults:
if os.path.exists('/usr/share/python3/debian_defaults'):
config = ConfigParser()
defaultsfile = open('/usr/share/python3/debian_defaults')
config.read_file(defaultsfile)
defaultsfile.close()
_defaults = config
if _defaults and name:
try:
value = _defaults.get('DEFAULT', name)
except NoOptionError:
raise ValueError
return value
return None
def version_to_tuple(version):
return tuple(int(part) for part in version.split('.'))
def parse_versions(vstring):
if len(vstring.split(',')) > 2:
raise ValueError('too many arguments provided for X-Python3-Version: min and max only.')
import operator
operators = {None: operator.eq, '=': operator.eq,
'>=': operator.ge, '<=': operator.le,
'<<': operator.lt}
vinfo = {}
exact_versions = set()
version_range = set(supported_versions(version_only=True))
relop_seen = False
for field in vstring.split(','):
field = field.strip()
if field == 'all':
continue
if field in ('current', 'current_ext'):
continue
vinfo.setdefault('versions', set())
ve = re.compile(r'(>=|<=|<<|=)? *(\d\.\d+)$')
m = ve.match(field)
try:
if not m:
raise ValueError('error parsing Python3-Version attribute')
op, v = m.group(1), m.group(2)
vmaj, vmin = v.split('.')
if int(vmaj) < 3:
continue
if op in (None, '='):
exact_versions.add(v)
else:
relop_seen = True
filtop = operators[op]
version_range = [av for av in version_range if filtop(
version_to_tuple(av), version_to_tuple(v))]
except Exception:
raise ValueError('error parsing Python3-Version attribute')
if 'versions' in vinfo:
vinfo['versions'] = exact_versions
if relop_seen:
vinfo['versions'] = exact_versions.union(version_range)
return vinfo
def old_versions(version_only=False):
global _old_versions
if not _old_versions:
try:
value = read_default('old-versions')
_old_versions = [s.strip() for s in value.split(',')]
except ValueError:
_old_versions = []
if version_only:
return [v[6:] for v in _old_versions]
else:
return _old_versions
def unsupported_versions(version_only=False):
global _unsupported_versions
if not _unsupported_versions:
try:
value = read_default('unsupported-versions')
_unsupported_versions = [s.strip() for s in value.split(',')]
except ValueError:
_unsupported_versions = []
if version_only:
return [v[6:] for v in _unsupported_versions]
else:
return _unsupported_versions
def supported_versions(version_only=False):
global _supported_versions,_default_version
default_version()
if not _supported_versions:
try:
value = read_default('supported-versions')
_supported_versions = [s.strip() for s in value.split(',')]
except ValueError:
cmd = ['/usr/bin/apt-cache', '--no-all-versions',
'show', 'python3-all']
try:
import subprocess
p = subprocess.Popen(cmd, bufsize=1,
shell=False, stdout=subprocess.PIPE)
fd = p.stdout
except ImportError:
fd = os.popen(' '.join(cmd))
depends = None
for line in fd:
if line.startswith('Depends:'):
depends = line.split(':', 1)[1].strip().split(',')
fd.close()
depends = [re.sub(r'\s*(\S+)[ (]?.*', r'\1', s) for s in depends]
_supported_versions = depends
default = _supported_versions.pop(_supported_versions.index(_default_version))
_supported_versions.sort()
_supported_versions.append(default)
if version_only:
return [v[6:] for v in _supported_versions]
else:
return _supported_versions
def default_version(version_only=False):
global _default_version
if not _default_version:
_default_version = os.readlink('/usr/bin/python3')
# consistency check
debian_default = read_default('default-version')
if not _default_version in (debian_default, os.path.join('/usr/bin', debian_default)):
raise ValueError("the symlink /usr/bin/python3 does not point to the "
"python3 default version. It must be reset "
"to point to %s" % debian_default)
_default_version = debian_default
if version_only:
return _default_version[6:]
else:
return _default_version
def requested_versions(vstring, version_only=False):
global _default_version
default_version()
versions = None
vinfo = parse_versions(vstring)
supported = supported_versions(version_only=True)
if len(vinfo) == 1:
versions = vinfo['versions'].intersection(supported)
vl = []
for version in versions: vl.append(version)
try:
default = vl.pop(vl.index(_default_version[6:]))
except:
default = ''
vl.sort()
if default:
vl.append(default)
else:
raise ValueError('No supported python3 versions in version string')
if not versions:
raise ValueError('empty set of versions')
if version_only:
return vl
else:
return ['python%s' % v for v in vl]
def installed_versions(version_only=False):
import glob
supported = supported_versions()
versions = [os.path.basename(s)
for s in glob.glob('/usr/bin/python3.[0-9]') + glob.glob('/usr/bin/python3.[0-9][0-9]')
if os.path.basename(s) in supported]
versions.sort()
if version_only:
return [v[6:] for v in versions]
else:
return versions
def minmax_supported_version(minmax, version_only=False):
supported_versions_list = supported_versions(True)
version = minmax(version_to_tuple(ver) for ver in supported_versions_list)
version_str = '%d.%d' % version
if version_only:
return version_str
else:
return 'python' + version_str
class ControlFileValueError(ValueError):
pass
class MissingVersionValueError(ValueError):
pass
def extract_pyversion_attribute(fn, pkg):
"""read the debian/control file, extract the X-Python3-Version
field."""
version = None
sversion = None
section = None
with open(fn, encoding='utf-8') as controlfile:
lines = [line.strip() for line in controlfile]
for line in lines:
if line == '' and section != None:
if pkg == 'Source':
break
section = None
elif line.startswith('Source:'):
section = 'Source'
elif line.startswith('Package: ' + pkg):
section = pkg
elif line.lower().startswith('x-python3-version:'):
if section != 'Source':
raise ValueError('attribute X-Python3-Version not in Source section')
sversion = line.split(':', 1)[1].strip()
if section is None:
raise ControlFileValueError('not a control file')
if pkg == 'Source':
if sversion is None:
raise MissingVersionValueError('no X-Python3-Version in control file')
return sversion
return version
'''
def requested_versions_bis(vstring, version_only=False):
versions = []
py_supported_short = supported_versions(version_only=True)
for item in vstring.split(','):
v=item.split('-')
if len(v)>1:
if not v[0]:
v[0] = py_supported_short[0]
if not v[1]:
v[1] = py_supported_short[-1]
for ver in py_supported_short:
try:
if version_cmp(ver,v[0]) >= 0 \
and version_cmp(ver,v[1]) <= 0:
versions.append(ver)
except ValueError:
pass
else:
if v[0] in py_supported_short:
versions.append(v[0])
versions.sort(version_cmp)
if not versions:
raise ValueError('empty set of versions')
if not version_only:
versions=['python'+i for i in versions]
return versions
'''
def main():
from optparse import OptionParser
usage = '[-v] [-h] [-d|--default] [-s|--supported] [-i|--installed] '
'[-r|--requested <version string>|<control file>]'
parser = OptionParser(usage=usage)
parser.add_option('-d', '--default',
help='print the default python3 version',
action='store_true', dest='default')
parser.add_option('-s', '--supported',
help='print the supported python3 versions',
action='store_true', dest='supported')
parser.add_option('-r', '--requested',
help='print the python3 versions requested by a build; '
'the argument is either the name of a control file '
'or the value of the X-Python3-Version attribute',
action='store_true', dest='requested')
parser.add_option('-i', '--installed',
help='print the installed supported python3 versions',
action='store_true', dest='installed')
parser.add_option('--min-supported',
help='print the minimum supported python3 version',
action='store_true', dest='minsupported')
parser.add_option('--max-supported',
help='print the maximum supported python3 version',
action='store_true', dest='maxsupported')
parser.add_option('-v', '--version',
help='print just the version number(s)',
default=False, action='store_true', dest='version_only')
opts, args = parser.parse_args()
program = os.path.basename(sys.argv[0])
if opts.default and len(args) == 0:
try:
print(default_version(opts.version_only))
except ValueError as msg:
print("%s:" % program, msg)
sys.exit(1)
elif opts.supported and len(args) == 0:
print(' '.join(supported_versions(opts.version_only)))
elif opts.installed and len(args) == 0:
print(' '.join(installed_versions(opts.version_only)))
elif opts.minsupported and len(args) == 0:
print(minmax_supported_version(min, opts.version_only))
elif opts.maxsupported and len(args) == 0:
print(minmax_supported_version(max, opts.version_only))
elif opts.requested and len(args) <= 1:
if len(args) == 0:
versions = 'debian/control'
else:
versions = args[0]
try:
if os.path.isfile(versions):
fn = versions
try:
vstring = extract_pyversion_attribute(fn, 'Source')
vs = requested_versions(vstring, opts.version_only)
except ControlFileValueError:
sys.stderr.write("%s: not a control file: %s, "
% (program, fn))
sys.exit(1)
except MissingVersionValueError:
sys.stderr.write("%s: no X-Python3-Version in control "
"file, using supported versions\n" %
program)
vs = supported_versions(opts.version_only)
else:
vs = requested_versions(versions, opts.version_only)
print(' '.join(vs))
except ValueError as msg:
sys.stderr.write("%s: %s\n" % (program, msg))
sys.exit(1)
else:
sys.stderr.write("usage: %s %s\n" % (program, usage))
sys.exit(1)
if __name__ == '__main__':
main()
Mini Shell