qubes-installer-qubes-os/anaconda/pyanaconda/anaconda_optparse.py
2013-01-24 01:45:53 +01:00

127 lines
5.0 KiB
Python

#
# anaconda_optparse.py: option parsing for anaconda (CLI and boot args)
#
# Copyright (C) 2012 Red Hat, Inc. All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# Authors:
# Will Woods <wwoods@redhat.com>
from flags import BootArgs
from optparse import OptionParser, OptionConflictError
class AnacondaOptionParser(OptionParser):
"""
Subclass of OptionParser that also examines boot arguments.
If the "bootarg_prefix" keyword argument is set, it's assumed that all
bootargs will start with that prefix.
"require_prefix" is a bool:
False: accept the argument with or without the prefix.
True: ignore the argument without the prefix. (default)
"""
def __init__(self, *args, **kwargs):
self._boot_arg = dict()
self.bootarg_prefix = kwargs.pop("bootarg_prefix","")
self.require_prefix = kwargs.pop("require_prefix",True)
OptionParser.__init__(self, *args, **kwargs)
def add_option(self, *args, **kwargs):
"""
Add a new option - like OptionParser.add_option.
The long options will be added to the list of boot args, unless
the keyword argument 'bootarg' is set to False.
Positional arguments that don't start with '-' are considered extra
boot args to look for.
NOTE: conflict_handler is currently ignored for boot args - they will
always raise OptionConflictError if they conflict.
"""
# TODO: add kwargs to make an option commandline-only or boot-arg-only
flags = [a for a in args if a.startswith('-')]
bootargs = [a for a in args if not a.startswith('-')]
do_bootarg = kwargs.pop("bootarg", True)
option = OptionParser.add_option(self, *flags, **kwargs)
bootargs += [flag[2:] for flag in option._long_opts]
if do_bootarg:
for b in bootargs:
if b in self._boot_arg:
raise OptionConflictError(
"conflicting bootopt string: %s" % b, option)
else:
self._boot_arg[b] = option
return option
def _get_bootarg_option(self, arg):
"""Find the correct Option for a given bootarg (if one exists)"""
if self.bootarg_prefix and arg.startswith(self.bootarg_prefix):
prefixed_option = True
arg = arg[len(self.bootarg_prefix):]
else:
prefixed_option = False
option = self._boot_arg.get(arg)
if self.require_prefix and not prefixed_option:
return None
if option and self.bootarg_prefix and not prefixed_option:
self.deprecated_bootargs.append(arg)
return option
def parse_boot_cmdline(self, cmdline, values=None):
"""
Parse the boot cmdline and set appropriate values according to
the options set by add_option.
cmdline can be given as a string (to be parsed by BootArgs), or a
dict (or any object with .iteritems()) of {bootarg:value} pairs.
If cmdline is None, the cmdline data will be whatever BootArgs reads
by default (/proc/cmdline, /run/initramfs/etc/cmdline, /etc/cmdline).
If an option requires a value but the boot arg doesn't provide one,
we'll quietly not set anything.
"""
if cmdline is None or type(cmdline) is str:
bootargs = BootArgs(cmdline)
else:
bootargs = cmdline
self.deprecated_bootargs = []
for arg, val in bootargs.iteritems():
option = self._get_bootarg_option(arg)
if option is None:
continue
if option.takes_value() and val is None:
continue # TODO: emit a warning or something there?
if option.action == "store_true" and val in ("0", "no", "off"):
# special case: "mpath=0" would otherwise set mpath to True
setattr(values, option.dest, False)
continue
option.process(arg, val, values, self)
return values
def parse_args(self, args=None, values=None, cmdline=None):
"""
Like OptionParser.parse_args(), but also parses the boot cmdline.
(see parse_boot_cmdline for details on that process.)
Commandline arguments will override boot arguments.
"""
if values is None:
values = self.get_default_values()
v = self.parse_boot_cmdline(cmdline, values)
return OptionParser.parse_args(self, args, v)