Permalink
Cannot retrieve contributors at this time
Name already in use
A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
bup/lib/bup/options.py /
Go to fileThis commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
275 lines (237 sloc)
9.8 KB
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
# Copyright 2010-2012 Avery Pennarun and options.py contributors. | |
# All rights reserved. | |
# | |
# (This license applies to this file but not necessarily the other files in | |
# this package.) | |
# | |
# Redistribution and use in source and binary forms, with or without | |
# modification, are permitted provided that the following conditions are | |
# met: | |
# | |
# 1. Redistributions of source code must retain the above copyright | |
# notice, this list of conditions and the following disclaimer. | |
# | |
# 2. Redistributions in binary form must reproduce the above copyright | |
# notice, this list of conditions and the following disclaimer in | |
# the documentation and/or other materials provided with the | |
# distribution. | |
# | |
# THIS SOFTWARE IS PROVIDED BY AVERY PENNARUN ``AS IS'' AND ANY | |
# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | |
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> OR | |
# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF | |
# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING | |
# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS | |
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
# | |
"""Command-line options parser. | |
With the help of an options spec string, easily parse command-line options. | |
An options spec is made up of two parts, separated by a line with two dashes. | |
The first part is the synopsis of the command and the second one specifies | |
options, one per line. | |
Each non-empty line in the synopsis gives a set of options that can be used | |
together. | |
Option flags must be at the begining of the line and multiple flags are | |
separated by commas. Usually, options have a short, one character flag, and a | |
longer one, but the short one can be omitted. | |
Long option flags are used as the option's key for the OptDict produced when | |
parsing options. | |
When the flag definition is ended with an equal sign, the option takes | |
one string as an argument, and that string will be converted to an | |
integer when possible. Otherwise, the option does not take an argument | |
and corresponds to a boolean flag that is true when the option is | |
given on the command line. | |
The option's description is found at the right of its flags definition, after | |
one or more spaces. The description ends at the end of the line. If the | |
description contains text enclosed in square brackets, the enclosed text will | |
be used as the option's default value. | |
Options can be put in different groups. Options in the same group must be on | |
consecutive lines. Groups are formed by inserting a line that begins with a | |
space. The text on that line will be output after an empty line. | |
""" | |
import sys, os, textwrap, getopt, re, struct | |
def _invert(v, invert): | |
if invert: | |
return not v | |
return v | |
def _remove_negative_kv(k, v): | |
if k.startswith('no-') or k.startswith('no_'): | |
return k[3:], not v | |
return k,v | |
class OptDict(object): | |
"""Dictionary that exposes keys as attributes. | |
Keys can be set or accessed with a "no-" or "no_" prefix to negate the | |
value. | |
""" | |
def __init__(self, aliases): | |
self._opts = {} | |
self._aliases = aliases | |
def _unalias(self, k): | |
k, reinvert = _remove_negative_kv(k, False) | |
k, invert = self._aliases[k] | |
return k, invert ^ reinvert | |
def __setitem__(self, k, v): | |
k, invert = self._unalias(k) | |
self._opts[k] = _invert(v, invert) | |
def __getitem__(self, k): | |
k, invert = self._unalias(k) | |
return _invert(self._opts[k], invert) | |
def __getattr__(self, k): | |
return self[k] | |
def _default_onabort(msg): | |
sys.exit(97) | |
def _intify(v): | |
try: | |
vv = int(v or '') | |
if str(vv) == v: | |
return vv | |
except ValueError: | |
pass | |
return v | |
def _atoi(v): | |
try: | |
return int(v or 0) | |
except ValueError: | |
return 0 | |
def _tty_width(): | |
s = struct.pack("HHHH", 0, 0, 0, 0) | |
try: | |
import fcntl, termios | |
s = fcntl.ioctl(sys.stderr.fileno(), termios.TIOCGWINSZ, s) | |
except (IOError, ImportError): | |
return _atoi(os.environ.get('WIDTH')) or 70 | |
(ysize,xsize,ypix,xpix) = struct.unpack('HHHH', s) | |
return xsize or 70 | |
class Options: | |
"""Option parser. | |
When constructed, a string called an option spec must be given. It | |
specifies the synopsis and option flags and their description. For more | |
information about option specs, see the docstring at the top of this file. | |
Two optional arguments specify an alternative parsing function and an | |
alternative behaviour on abort (after having output the usage string). | |
By default, the parser function is getopt.gnu_getopt, and the abort | |
behaviour is to exit the program. | |
""" | |
def __init__(self, optspec, optfunc=getopt.gnu_getopt, | |
onabort=_default_onabort): | |
self.optspec = optspec | |
self._onabort = onabort | |
self.optfunc = optfunc | |
self._aliases = {} | |
self._shortopts = 'h?' | |
self._longopts = ['help', 'usage'] | |
self._hasparms = {} | |
self._defaults = {} | |
self._usagestr = self._gen_usage() # this also parses the optspec | |
def _gen_usage(self): | |
out = [] | |
lines = self.optspec.strip().split('\n') | |
lines.reverse() | |
first_syn = True | |
while lines: | |
l = lines.pop() | |
if l == '--': break | |
out.append('%s: %s\n' % (first_syn and 'usage' or ' or', l)) | |
first_syn = False | |
out.append('\n') | |
last_was_option = False | |
while lines: | |
l = lines.pop() | |
if l.startswith(' '): | |
out.append('%s%s\n' % (last_was_option and '\n' or '', | |
l.lstrip())) | |
last_was_option = False | |
elif l: | |
(flags,extra) = (l + ' ').split(' ', 1) | |
extra = extra.strip() | |
if flags.endswith('='): | |
flags = flags[:-1] | |
has_parm = 1 | |
else: | |
has_parm = 0 | |
g = re.search(r'\[([^\]]*)\]$', extra) | |
if g: | |
defval = _intify(g.group(1)) | |
else: | |
defval = None | |
flagl = flags.split(',') | |
flagl_nice = [] | |
flag_main, invert_main = _remove_negative_kv(flagl[0], False) | |
self._defaults[flag_main] = _invert(defval, invert_main) | |
for _f in flagl: | |
f,invert = _remove_negative_kv(_f, 0) | |
self._aliases[f] = (flag_main, invert_main ^ invert) | |
self._hasparms[f] = has_parm | |
if f == '#': | |
self._shortopts += '0123456789' | |
flagl_nice.append('-#') | |
elif len(f) == 1: | |
self._shortopts += f + (has_parm and ':' or '') | |
flagl_nice.append('-' + f) | |
else: | |
f_nice = re.sub(r'\W', '_', f) | |
self._aliases[f_nice] = (flag_main, | |
invert_main ^ invert) | |
self._longopts.append(f + (has_parm and '=' or '')) | |
self._longopts.append('no-' + f) | |
flagl_nice.append('--' + _f) | |
flags_nice = ', '.join(flagl_nice) | |
if has_parm: | |
flags_nice += ' ...' | |
prefix = ' %-20s ' % flags_nice | |
argtext = '\n'.join(textwrap.wrap(extra, width=_tty_width(), | |
initial_indent=prefix, | |
subsequent_indent=' '*28)) | |
out.append(argtext + '\n') | |
last_was_option = True | |
else: | |
out.append('\n') | |
last_was_option = False | |
return ''.join(out).rstrip() + '\n' | |
def usage(self, msg=""): | |
"""Print usage string to stderr and abort.""" | |
sys.stderr.write(self._usagestr) | |
if msg: | |
sys.stderr.write(msg) | |
e = self._onabort and self._onabort(msg) or None | |
if e: | |
raise e | |
def fatal(self, msg): | |
"""Print an error message to stderr and abort with usage string.""" | |
msg = '\nerror: %s\n' % msg | |
return self.usage(msg) | |
def parse(self, args): | |
"""Parse a list of arguments and return (options, flags, extra). | |
In the returned tuple, "options" is an OptDict with known options, | |
"flags" is a list of option flags that were used on the command-line, | |
and "extra" is a list of positional arguments. | |
""" | |
try: | |
(flags,extra) = self.optfunc(args, self._shortopts, self._longopts) | |
except getopt.GetoptError, e: | |
self.fatal(e) | |
opt = OptDict(aliases=self._aliases) | |
for k,v in self._defaults.iteritems(): | |
opt[k] = v | |
for (k,v) in flags: | |
k = k.lstrip('-') | |
if k in ('h', '?', 'help', 'usage'): | |
self.usage() | |
if (self._aliases.get('#') and | |
k in ('0','1','2','3','4','5','6','7','8','9')): | |
v = int(k) # guaranteed to be exactly one digit | |
k, invert = self._aliases['#'] | |
opt['#'] = v | |
else: | |
k, invert = opt._unalias(k) | |
if not self._hasparms[k]: | |
assert(v == '') | |
v = (opt._opts.get(k) or 0) + 1 | |
else: | |
v = _intify(v) | |
opt[k] = _invert(v, invert) | |
return (opt,flags,extra) |