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Edit File: pyversions
#! /usr/bin/python2 import os, re, sys try: SetType = set except NameError: import sets SetType = sets.Set set = sets.Set _defaults = None def read_default(name=None): global _defaults from ConfigParser import SafeConfigParser, NoOptionError if not _defaults: if os.path.exists('/usr/share/python/debian_defaults'): config = SafeConfigParser() try: config.readfp(file('/usr/share/python/debian_defaults')) except IOError, msg: print msg sys.exit(1) _defaults = config if _defaults and name: try: value = _defaults.get('DEFAULT', name) except NoOptionError: raise ValueError return value return None def parse_versions(vstring, add_exact=False): 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) + old_versions(version_only=True)) relop_seen = False for field in vstring.split(','): field = field.strip() if field == 'all': vinfo['all'] = 'all' continue if field in ('current', 'current_ext'): vinfo['current'] = field continue vinfo.setdefault('versions', set()) ve = re.compile('(>=|<=|<<|=)? *(\d\.\d)$') m = ve.match(field) try: if not m: raise ValueError('error parsing Python-Version attribute') op, v = m.group(1), m.group(2) vmaj, vmin = v.split('.') # Don't silently ignore Python 3 versions. if int(vmaj) > 2: raise ValueError('error parsing Python-Version attribute, Python 3 version found') 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(av ,v)] except Exception: raise ValueError, 'error parsing Python-Version attribute' if add_exact: if exact_versions: vinfo['vexact'] = exact_versions if 'versions' in vinfo: if relop_seen: vinfo['versions'] = set(version_range) else: del vinfo['versions'] else: if 'versions' in vinfo: vinfo['versions'] = exact_versions if relop_seen: vinfo['versions'] = exact_versions.union(version_range) return vinfo _old_versions = None 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 _unsupported_versions = None 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 _supported_versions = ["python%s" % ver.strip() for ver in os.environ.get('DEBPYTHON_SUPPORTED', '').split(',') if ver.strip()] def supported_versions(version_only=False): global _supported_versions 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', 'python-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() if depends: depends = [re.sub(r'\s*(\S+)[ (]?.*', r'\1', s) for s in depends] _supported_versions = depends if not _supported_versions: # last resort: python-minimal not installed, apt-cache # not available, hard code the value, #394084 _supported_versions = ['python2.6', 'python2.7'] if version_only: return [v[6:] for v in _supported_versions] else: return _supported_versions _default_version = "python%s" % os.environ.get('DEBPYTHON_DEFAULT', '') if _default_version == 'python': _default_version = None def default_version(version_only=False): global _default_version if not _default_version: try: _default_version = link = os.readlink('/usr/bin/python2') except OSError: _default_version = None try: cmd = ['/usr/bin/python2', '-c', 'import sys; print sys.version[:3]'] import subprocess p = subprocess.Popen(cmd, bufsize=1, shell=False, stdout=subprocess.PIPE) fd = p.stdout except ImportError: fd = os.popen("/usr/bin/python2 -c 'import sys; print sys.version[:3]'") line = fd.readline().strip() fd.close() if re.match(r'\d\.\d$', line): _default_version = 'python' + line # consistency check try: debian_default = read_default('default-version') except ValueError: debian_default = "python2.7" if not _default_version in (debian_default, os.path.join('/usr/bin', debian_default)): raise ValueError, "/usr/bin/python2 does not match the python2 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): versions = None vinfo = parse_versions(vstring, add_exact=True) supported = supported_versions(version_only=True) if len(vinfo) == 1: if 'all' in vinfo: versions = supported elif 'current' in vinfo: versions = [default_version(version_only=True)] elif 'vexact' in vinfo: versions = vinfo['vexact'] else: versions = vinfo['versions'].intersection(supported) elif 'all' in vinfo and 'current' in vinfo: raise ValueError, "both `current' and `all' in version string" elif 'all' in vinfo: if 'versions' in vinfo: versions = vinfo['versions'].intersection(supported) else: versions = set(supported) if 'vexact' in vinfo: versions.update(vinfo['vexact']) elif 'current' in vinfo: current = default_version(version_only=True) if not current in vinfo['versions']: raise ValueError, "`current' version not in supported versions" versions = [current] elif 'versions' in vinfo or 'vexact' in vinfo: versions = set() if 'versions' in vinfo: versions = vinfo['versions'].intersection(supported) if 'vexact' in vinfo: versions.update(vinfo['vexact']) else: raise ValueError, 'No Python versions in version string' if not versions: raise ValueError('computed set of supported versions is empty') if version_only: return versions else: return ['python%s' % v for v in versions] def installed_versions(version_only=False): import glob supported = supported_versions() versions = [os.path.basename(s) for s in glob.glob('/usr/bin/python[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 class ControlFileValueError(ValueError): pass class MissingVersionValueError(ValueError): pass def extract_pyversion_attribute(fn, pkg): """read the debian/control file, extract the X-Python-Version or XS-Python-Version field; check that XB-Python-Version exists for the package.""" version = None sversion = None section = None try: fp = file(fn, 'r') except IOError, msg: print "Cannot open %s: %s" % (fn, msg) sys.exit(2) for line in fp: line = line.strip() if line == '': if section == None: continue if pkg == 'Source': break section = None elif line.startswith('Source:'): section = 'Source' elif line.startswith('Package: ' + pkg): section = pkg elif line.lower().startswith(('xs-python-version:', 'x-python-version:')): if section != 'Source': raise ValueError, \ 'attribute X(S)-Python-Version not in Source section' sversion = line.split(':', 1)[1].strip() elif line.lower().startswith('xb-python-version:'): if section == pkg: version = line.split(':', 1)[1].strip() if section == None: raise ControlFileValueError, 'not a control file' if pkg == 'Source': if sversion == None: raise MissingVersionValueError, \ 'no X(S)-Python-Version in control file' return sversion if version == None: raise MissingVersionValueError, \ 'no XB-Python-Version for package `%s' % pkg return version # compatibility functions to parse debian/pyversions def version_cmp(ver1,ver2): v1=[int(i) for i in ver1.split('.')] v2=[int(i) for i in ver2.split('.')] return cmp(v1,v2) 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 extract_pyversion_attribute_bis(fn): vstring = file(fn).readline().rstrip('\n') return vstring 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 python version', action='store_true', dest='default') parser.add_option('-s', '--supported', help='print the supported python versions', action='store_true', dest='supported') parser.add_option('-r', '--requested', help='print the python versions requested by a build; the argument is either the name of a control file or the value of the X(S)-Python-Version attribute', action='store_true', dest='requested') parser.add_option('-i', '--installed', help='print the installed supported python versions', action='store_true', dest='installed') 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, 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.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: fn = os.path.join(os.path.dirname(fn), 'pyversions') sys.stderr.write("%s: missing X(S)-Python-Version in control file, fall back to %s\n" \ % (program, fn)) try: vstring = extract_pyversion_attribute_bis(fn) vs = requested_versions_bis(vstring, opts.version_only) except IOError: sys.stderr.write("%s: missing debian/pyversions file, fall back to supported versions\n" \ % program) vs = supported_versions(opts.version_only) except ValueError, e: sys.stderr.write("%s: %s\n" % (program, e)) sys.exit(4) else: vs = requested_versions(versions, opts.version_only) print ' '.join(vs) except ValueError, 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()