The Tor Browser: config/configobj.py@97036ab72558 (annotated)

config/configobj.py@97036ab72558 (annotated)

config/configobj.py

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 # configobj.py
 # A config file reader/writer that supports nested sections in config files.
 # Copyright (C) 2005-2006 Michael Foord, Nicola Larosa
 # E-mail: fuzzyman AT voidspace DOT org DOT uk
 #         nico AT tekNico DOT net
 # ConfigObj 4
 # http://www.voidspace.org.uk/python/configobj.html
 # Released subject to the BSD License
 # Please see http://www.voidspace.org.uk/python/license.shtml
 # Scripts maintained at http://www.voidspace.org.uk/python/index.shtml
 # For information about bugfixes, updates and support, please join the
 # ConfigObj mailing list:
 # http://lists.sourceforge.net/lists/listinfo/configobj-develop
 # Comments, suggestions and bug reports welcome.
 from __future__ import generators
 import sys
 INTP_VER = sys.version_info[:2]
 if INTP_VER < (2, 2):
     raise RuntimeError("Python v.2.2 or later needed")
 import os, re
 compiler = None
 try:
     import compiler
 except ImportError:
     # for IronPython
     pass
 from types import StringTypes
 from warnings import warn
 try:
     from codecs import BOM_UTF8, BOM_UTF16, BOM_UTF16_BE, BOM_UTF16_LE
 except ImportError:
     # Python 2.2 does not have these
     # UTF-8
     BOM_UTF8 = '\xef\xbb\xbf'
     # UTF-16, little endian
     BOM_UTF16_LE = '\xff\xfe'
     # UTF-16, big endian
     BOM_UTF16_BE = '\xfe\xff'
     if sys.byteorder == 'little':
         # UTF-16, native endianness
         BOM_UTF16 = BOM_UTF16_LE
     else:
         # UTF-16, native endianness
         BOM_UTF16 = BOM_UTF16_BE
 # A dictionary mapping BOM to
 # the encoding to decode with, and what to set the
 # encoding attribute to.
 BOMS = {
     BOM_UTF8: ('utf_8', None),
     BOM_UTF16_BE: ('utf16_be', 'utf_16'),
     BOM_UTF16_LE: ('utf16_le', 'utf_16'),
     BOM_UTF16: ('utf_16', 'utf_16'),
     }
 # All legal variants of the BOM codecs.
 # TODO: the list of aliases is not meant to be exhaustive, is there a
 #   better way ?
 BOM_LIST = {
     'utf_16': 'utf_16',
     'u16': 'utf_16',
     'utf16': 'utf_16',
     'utf-16': 'utf_16',
     'utf16_be': 'utf16_be',
     'utf_16_be': 'utf16_be',
     'utf-16be': 'utf16_be',
     'utf16_le': 'utf16_le',
     'utf_16_le': 'utf16_le',
     'utf-16le': 'utf16_le',
     'utf_8': 'utf_8',
     'u8': 'utf_8',
     'utf': 'utf_8',
     'utf8': 'utf_8',
     'utf-8': 'utf_8',
     }
 # Map of encodings to the BOM to write.
 BOM_SET = {
     'utf_8': BOM_UTF8,
     'utf_16': BOM_UTF16,
     'utf16_be': BOM_UTF16_BE,
     'utf16_le': BOM_UTF16_LE,
     None: BOM_UTF8
     }
 try:
     from validate import VdtMissingValue
 except ImportError:
     VdtMissingValue = None
 try:
     enumerate
 except NameError:
     def enumerate(obj):
         """enumerate for Python 2.2."""
         i = -1
         for item in obj:
             i += 1
             yield i, item
 try:
     True, False
 except NameError:
     True, False = 1, 0
 __version__ = '4.4.0'
 __revision__ = '$Id: configobj.py,v 3.5 2007/07/02 18:20:24 benjamin%smedbergs.us Exp $'
 __docformat__ = "restructuredtext en"
 __all__ = (
     '__version__',
     'DEFAULT_INDENT_TYPE',
     'DEFAULT_INTERPOLATION',
     'ConfigObjError',
     'NestingError',
     'ParseError',
     'DuplicateError',
     'ConfigspecError',
     'ConfigObj',
     'SimpleVal',
     'InterpolationError',
     'InterpolationLoopError',
     'MissingInterpolationOption',
     'RepeatSectionError',
     'UnreprError',
     'UnknownType',
     '__docformat__',
     'flatten_errors',
 )
 DEFAULT_INTERPOLATION = 'configparser'
 DEFAULT_INDENT_TYPE = '    '
 MAX_INTERPOL_DEPTH = 10
 OPTION_DEFAULTS = {
     'interpolation': True,
     'raise_errors': False,
     'list_values': True,
     'create_empty': False,
     'file_error': False,
     'configspec': None,
     'stringify': True,
     # option may be set to one of ('', ' ', '\t')
     'indent_type': None,
     'encoding': None,
     'default_encoding': None,
     'unrepr': False,
     'write_empty_values': False,
 }
 def getObj(s):
     s = "a=" + s
     if compiler is None:
         raise ImportError('compiler module not available')
     p = compiler.parse(s)
     return p.getChildren()[1].getChildren()[0].getChildren()[1]
 class UnknownType(Exception):
     pass
 class Builder:
     def build(self, o):
         m = getattr(self, 'build_' + o.__class__.__name__, None)
         if m is None:
             raise UnknownType(o.__class__.__name__)
         return m(o)
     def build_List(self, o):
         return map(self.build, o.getChildren())
     def build_Const(self, o):
         return o.value
     def build_Dict(self, o):
         d = {}
         i = iter(map(self.build, o.getChildren()))
         for el in i:
             d[el] = i.next()
         return d
     def build_Tuple(self, o):
         return tuple(self.build_List(o))
     def build_Name(self, o):
         if o.name == 'None':
             return None
         if o.name == 'True':
             return True
         if o.name == 'False':
             return False
         # An undefinted Name
         raise UnknownType('Undefined Name')
     def build_Add(self, o):
         real, imag = map(self.build_Const, o.getChildren())
         try:
             real = float(real)
         except TypeError:
             raise UnknownType('Add')
         if not isinstance(imag, complex) or imag.real != 0.0:
             raise UnknownType('Add')
         return real+imag
     def build_Getattr(self, o):
         parent = self.build(o.expr)
         return getattr(parent, o.attrname)
     def build_UnarySub(self, o):
         return -self.build_Const(o.getChildren()[0])
     def build_UnaryAdd(self, o):
         return self.build_Const(o.getChildren()[0])
 def unrepr(s):
     if not s:
         return s
     return Builder().build(getObj(s))
 def _splitlines(instring):
     """Split a string on lines, without losing line endings or truncating."""
 class ConfigObjError(SyntaxError):
     """
     This is the base class for all errors that ConfigObj raises.
     It is a subclass of SyntaxError.
     """
     def __init__(self, message='', line_number=None, line=''):
         self.line = line
         self.line_number = line_number
         self.message = message
         SyntaxError.__init__(self, message)
 class NestingError(ConfigObjError):
     """
     This error indicates a level of nesting that doesn't match.
     """
 class ParseError(ConfigObjError):
     """
     This error indicates that a line is badly written.
     It is neither a valid ``key = value`` line,
     nor a valid section marker line.
     """
 class DuplicateError(ConfigObjError):
     """
     The keyword or section specified already exists.
     """
 class ConfigspecError(ConfigObjError):
     """
     An error occurred whilst parsing a configspec.
     """
 class InterpolationError(ConfigObjError):
     """Base class for the two interpolation errors."""
 class InterpolationLoopError(InterpolationError):
     """Maximum interpolation depth exceeded in string interpolation."""
     def __init__(self, option):
         InterpolationError.__init__(
             self,
             'interpolation loop detected in value "%s".' % option)
 class RepeatSectionError(ConfigObjError):
     """
     This error indicates additional sections in a section with a
     ``__many__`` (repeated) section.
     """
 class MissingInterpolationOption(InterpolationError):
     """A value specified for interpolation was missing."""
     def __init__(self, option):
         InterpolationError.__init__(
             self,
             'missing option "%s" in interpolation.' % option)
 class UnreprError(ConfigObjError):
     """An error parsing in unrepr mode."""
 class InterpolationEngine(object):
     """
     A helper class to help perform string interpolation.
     This class is an abstract base class; its descendants perform
     the actual work.
     """
     # compiled regexp to use in self.interpolate()
     _KEYCRE = re.compile(r"%\(([^)]*)\)s")
     def __init__(self, section):
         # the Section instance that "owns" this engine
         self.section = section
     def interpolate(self, key, value):
         def recursive_interpolate(key, value, section, backtrail):
             """The function that does the actual work.
             ``value``: the string we're trying to interpolate.
             ``section``: the section in which that string was found
             ``backtrail``: a dict to keep track of where we've been,
             to detect and prevent infinite recursion loops
             This is similar to a depth-first-search algorithm.
             """
             # Have we been here already?
             if backtrail.has_key((key, section.name)):
                 # Yes - infinite loop detected
                 raise InterpolationLoopError(key)
             # Place a marker on our backtrail so we won't come back here again
             backtrail[(key, section.name)] = 1
             # Now start the actual work
             match = self._KEYCRE.search(value)
             while match:
                 # The actual parsing of the match is implementation-dependent,
                 # so delegate to our helper function
                 k, v, s = self._parse_match(match)
                 if k is None:
                     # That's the signal that no further interpolation is needed
                     replacement = v
                 else:
                     # Further interpolation may be needed to obtain final value
                     replacement = recursive_interpolate(k, v, s, backtrail)
                 # Replace the matched string with its final value
                 start, end = match.span()
                 value = ''.join((value[:start], replacement, value[end:]))
                 new_search_start = start + len(replacement)
                 # Pick up the next interpolation key, if any, for next time
                 # through the while loop
                 match = self._KEYCRE.search(value, new_search_start)
             # Now safe to come back here again; remove marker from backtrail
             del backtrail[(key, section.name)]
             return value
         # Back in interpolate(), all we have to do is kick off the recursive
         # function with appropriate starting values
         value = recursive_interpolate(key, value, self.section, {})
         return value
     def _fetch(self, key):
         """Helper function to fetch values from owning section.
         Returns a 2-tuple: the value, and the section where it was found.
         """
         # switch off interpolation before we try and fetch anything !
         save_interp = self.section.main.interpolation
         self.section.main.interpolation = False
         # Start at section that "owns" this InterpolationEngine
         current_section = self.section
         while True:
             # try the current section first
             val = current_section.get(key)
             if val is not None:
                 break
             # try "DEFAULT" next
             val = current_section.get('DEFAULT', {}).get(key)
             if val is not None:
                 break
             # move up to parent and try again
             # top-level's parent is itself
             if current_section.parent is current_section:
                 # reached top level, time to give up
                 break
             current_section = current_section.parent
         # restore interpolation to previous value before returning
         self.section.main.interpolation = save_interp
         if val is None:
             raise MissingInterpolationOption(key)
         return val, current_section
     def _parse_match(self, match):
         """Implementation-dependent helper function.
         Will be passed a match object corresponding to the interpolation
         key we just found (e.g., "%(foo)s" or "$foo"). Should look up that
         key in the appropriate config file section (using the ``_fetch()``
         helper function) and return a 3-tuple: (key, value, section)
         ``key`` is the name of the key we're looking for
         ``value`` is the value found for that key
         ``section`` is a reference to the section where it was found
         ``key`` and ``section`` should be None if no further
         interpolation should be performed on the resulting value
         (e.g., if we interpolated "$$" and returned "$").
         """
         raise NotImplementedError
 class ConfigParserInterpolation(InterpolationEngine):
     """Behaves like ConfigParser."""
     _KEYCRE = re.compile(r"%\(([^)]*)\)s")
     def _parse_match(self, match):
         key = match.group(1)
         value, section = self._fetch(key)
         return key, value, section
 class TemplateInterpolation(InterpolationEngine):
     """Behaves like string.Template."""
     _delimiter = '$'
     _KEYCRE = re.compile(r"""
         \$(?:
           (?P<escaped>\$)              |   # Two $ signs
           (?P<named>[_a-z][_a-z0-9]*)  |   # $name format
           {(?P<braced>[^}]*)}              # ${name} format
         )
         """, re.IGNORECASE | re.VERBOSE)
     def _parse_match(self, match):
         # Valid name (in or out of braces): fetch value from section
         key = match.group('named') or match.group('braced')
         if key is not None:
             value, section = self._fetch(key)
             return key, value, section
         # Escaped delimiter (e.g., $$): return single delimiter
         if match.group('escaped') is not None:
             # Return None for key and section to indicate it's time to stop
             return None, self._delimiter, None
         # Anything else: ignore completely, just return it unchanged
         return None, match.group(), None
 interpolation_engines = {
     'configparser': ConfigParserInterpolation,
     'template': TemplateInterpolation,
 }
 class Section(dict):
     """
     A dictionary-like object that represents a section in a config file.
     It does string interpolation if the 'interpolation' attribute
     of the 'main' object is set to True.
     Interpolation is tried first from this object, then from the 'DEFAULT'
     section of this object, next from the parent and its 'DEFAULT' section,
     and so on until the main object is reached.
     A Section will behave like an ordered dictionary - following the
     order of the ``scalars`` and ``sections`` attributes.
     You can use this to change the order of members.
     Iteration follows the order: scalars, then sections.
     """
     def __init__(self, parent, depth, main, indict=None, name=None):
         """
         * parent is the section above
         * depth is the depth level of this section
         * main is the main ConfigObj
         * indict is a dictionary to initialise the section with
         """
         if indict is None:
             indict = {}
         dict.__init__(self)
         # used for nesting level *and* interpolation
         self.parent = parent
         # used for the interpolation attribute
         self.main = main
         # level of nesting depth of this Section
         self.depth = depth
         # the sequence of scalar values in this Section
         self.scalars = []
         # the sequence of sections in this Section
         self.sections = []
         # purely for information
         self.name = name
         # for comments :-)
         self.comments = {}
         self.inline_comments = {}
         # for the configspec
         self.configspec = {}
         self._order = []
         self._configspec_comments = {}
         self._configspec_inline_comments = {}
         self._cs_section_comments = {}
         self._cs_section_inline_comments = {}
         # for defaults
         self.defaults = []
         #
         # we do this explicitly so that __setitem__ is used properly
         # (rather than just passing to ``dict.__init__``)
         for entry in indict:
             self[entry] = indict[entry]
     def _interpolate(self, key, value):
         try:
             # do we already have an interpolation engine?
             engine = self._interpolation_engine
         except AttributeError:
             # not yet: first time running _interpolate(), so pick the engine
             name = self.main.interpolation
             if name == True:  # note that "if name:" would be incorrect here
                 # backwards-compatibility: interpolation=True means use default
                 name = DEFAULT_INTERPOLATION
             name = name.lower()  # so that "Template", "template", etc. all work
             class_ = interpolation_engines.get(name, None)
             if class_ is None:
                 # invalid value for self.main.interpolation
                 self.main.interpolation = False
                 return value
             else:
                 # save reference to engine so we don't have to do this again
                 engine = self._interpolation_engine = class_(self)
         # let the engine do the actual work
         return engine.interpolate(key, value)
     def __getitem__(self, key):
         """Fetch the item and do string interpolation."""
         val = dict.__getitem__(self, key)
         if self.main.interpolation and isinstance(val, StringTypes):
             return self._interpolate(key, val)
         return val
     def __setitem__(self, key, value, unrepr=False):
         """
         Correctly set a value.
         Making dictionary values Section instances.
         (We have to special case 'Section' instances - which are also dicts)
         Keys must be strings.
         Values need only be strings (or lists of strings) if
         ``main.stringify`` is set.
         `unrepr`` must be set when setting a value to a dictionary, without
         creating a new sub-section.
         """
         if not isinstance(key, StringTypes):
             raise ValueError, 'The key "%s" is not a string.' % key
         # add the comment
         if not self.comments.has_key(key):
             self.comments[key] = []
             self.inline_comments[key] = ''
         # remove the entry from defaults
         if key in self.defaults:
             self.defaults.remove(key)
         #
         if isinstance(value, Section):
             if not self.has_key(key):
                 self.sections.append(key)
             dict.__setitem__(self, key, value)
         elif isinstance(value, dict) and not unrepr:
             # First create the new depth level,
             # then create the section
             if not self.has_key(key):
                 self.sections.append(key)
             new_depth = self.depth + 1
             dict.__setitem__(
                 self,
                 key,
                 Section(
                     self,
                     new_depth,
                     self.main,
                     indict=value,
                     name=key))
         else:
             if not self.has_key(key):
                 self.scalars.append(key)
             if not self.main.stringify:
                 if isinstance(value, StringTypes):
                     pass
                 elif isinstance(value, (list, tuple)):
                     for entry in value:
                         if not isinstance(entry, StringTypes):
                             raise TypeError, (
                                 'Value is not a string "%s".' % entry)
                 else:
                     raise TypeError, 'Value is not a string "%s".' % value
             dict.__setitem__(self, key, value)
     def __delitem__(self, key):
         """Remove items from the sequence when deleting."""
         dict. __delitem__(self, key)
         if key in self.scalars:
             self.scalars.remove(key)
         else:
             self.sections.remove(key)
         del self.comments[key]
         del self.inline_comments[key]
     def get(self, key, default=None):
         """A version of ``get`` that doesn't bypass string interpolation."""
         try:
             return self[key]
         except KeyError:
             return default
     def update(self, indict):
         """
         A version of update that uses our ``__setitem__``.
         """
         for entry in indict:
             self[entry] = indict[entry]
     def pop(self, key, *args):
         """ """
         val = dict.pop(self, key, *args)
         if key in self.scalars:
             del self.comments[key]
             del self.inline_comments[key]
             self.scalars.remove(key)
         elif key in self.sections:
             del self.comments[key]
             del self.inline_comments[key]
             self.sections.remove(key)
         if self.main.interpolation and isinstance(val, StringTypes):
             return self._interpolate(key, val)
         return val
     def popitem(self):
         """Pops the first (key,val)"""
         sequence = (self.scalars + self.sections)
         if not sequence:
             raise KeyError, ": 'popitem(): dictionary is empty'"
         key = sequence[0]
         val =  self[key]
         del self[key]
         return key, val
     def clear(self):
         """
         A version of clear that also affects scalars/sections
         Also clears comments and configspec.
         Leaves other attributes alone :
             depth/main/parent are not affected
         """
         dict.clear(self)
         self.scalars = []
         self.sections = []
         self.comments = {}
         self.inline_comments = {}
         self.configspec = {}
     def setdefault(self, key, default=None):
         """A version of setdefault that sets sequence if appropriate."""
         try:
             return self[key]
         except KeyError:
             self[key] = default
             return self[key]
     def items(self):
         """ """
         return zip((self.scalars + self.sections), self.values())
     def keys(self):
         """ """
         return (self.scalars + self.sections)
     def values(self):
         """ """
         return [self[key] for key in (self.scalars + self.sections)]
     def iteritems(self):
         """ """
         return iter(self.items())
     def iterkeys(self):
         """ """
         return iter((self.scalars + self.sections))
     __iter__ = iterkeys
     def itervalues(self):
         """ """
         return iter(self.values())
     def __repr__(self):
         return '{%s}' % ', '.join([('%s: %s' % (repr(key), repr(self[key])))
             for key in (self.scalars + self.sections)])
     __str__ = __repr__
     # Extra methods - not in a normal dictionary
     def dict(self):
         """
         Return a deepcopy of self as a dictionary.
         All members that are ``Section`` instances are recursively turned to
         ordinary dictionaries - by calling their ``dict`` method.
         >>> n = a.dict()
         >>> n == a
 
         >>> n is a
 
         """
         newdict = {}
         for entry in self:
             this_entry = self[entry]
             if isinstance(this_entry, Section):
                 this_entry = this_entry.dict()
             elif isinstance(this_entry, list):
                 # create a copy rather than a reference
                 this_entry = list(this_entry)
             elif isinstance(this_entry, tuple):
                 # create a copy rather than a reference
                 this_entry = tuple(this_entry)
             newdict[entry] = this_entry
         return newdict
     def merge(self, indict):
         """
         A recursive update - useful for merging config files.
         >>> a = '''[section1]
         ...     option1 = True
         ...     [[subsection]]
         ...     more_options = False
         ...     # end of file'''.splitlines()
         >>> b = '''# File is user.ini
         ...     [section1]
         ...     option1 = False
         ...     # end of file'''.splitlines()
         >>> c1 = ConfigObj(b)
         >>> c2 = ConfigObj(a)
         >>> c2.merge(c1)
         >>> c2
         {'section1': {'option1': 'False', 'subsection': {'more_options': 'False'}}}
         """
         for key, val in indict.items():
             if (key in self and isinstance(self[key], dict) and
                                 isinstance(val, dict)):
                 self[key].merge(val)
             else:
                 self[key] = val
     def rename(self, oldkey, newkey):
         """
         Change a keyname to another, without changing position in sequence.
         Implemented so that transformations can be made on keys,
         as well as on values. (used by encode and decode)
         Also renames comments.
         """
         if oldkey in self.scalars:
             the_list = self.scalars
         elif oldkey in self.sections:
             the_list = self.sections
         else:
             raise KeyError, 'Key "%s" not found.' % oldkey
         pos = the_list.index(oldkey)
         #
         val = self[oldkey]
         dict.__delitem__(self, oldkey)
         dict.__setitem__(self, newkey, val)
         the_list.remove(oldkey)
         the_list.insert(pos, newkey)
         comm = self.comments[oldkey]
         inline_comment = self.inline_comments[oldkey]
         del self.comments[oldkey]
         del self.inline_comments[oldkey]
         self.comments[newkey] = comm
         self.inline_comments[newkey] = inline_comment
     def walk(self, function, raise_errors=True,
             call_on_sections=False, **keywargs):
         """
         Walk every member and call a function on the keyword and value.
         Return a dictionary of the return values
         If the function raises an exception, raise the errror
         unless ``raise_errors=False``, in which case set the return value to
         ``False``.
         Any unrecognised keyword arguments you pass to walk, will be pased on
         to the function you pass in.
         Note: if ``call_on_sections`` is ``True`` then - on encountering a
         subsection, *first* the function is called for the *whole* subsection,
         and then recurses into its members. This means your function must be
         able to handle strings, dictionaries and lists. This allows you
         to change the key of subsections as well as for ordinary members. The
         return value when called on the whole subsection has to be discarded.
         See  the encode and decode methods for examples, including functions.
         .. caution::
             You can use ``walk`` to transform the names of members of a section
             but you mustn't add or delete members.
         >>> config = '''[XXXXsection]
         ... XXXXkey = XXXXvalue'''.splitlines()
         >>> cfg = ConfigObj(config)
         >>> cfg
         {'XXXXsection': {'XXXXkey': 'XXXXvalue'}}
         >>> def transform(section, key):
         ...     val = section[key]
         ...     newkey = key.replace('XXXX', 'CLIENT1')
         ...     section.rename(key, newkey)
         ...     if isinstance(val, (tuple, list, dict)):
         ...         pass
         ...     else:
         ...         val = val.replace('XXXX', 'CLIENT1')
         ...         section[newkey] = val
         >>> cfg.walk(transform, call_on_sections=True)
         {'CLIENT1section': {'CLIENT1key': None}}
         >>> cfg
         {'CLIENT1section': {'CLIENT1key': 'CLIENT1value'}}
         """
         out = {}
         # scalars first
         for i in range(len(self.scalars)):
             entry = self.scalars[i]
             try:
                 val = function(self, entry, **keywargs)
                 # bound again in case name has changed
                 entry = self.scalars[i]
                 out[entry] = val
             except Exception:
                 if raise_errors:
                     raise
                 else:
                     entry = self.scalars[i]
                     out[entry] = False
         # then sections
         for i in range(len(self.sections)):
             entry = self.sections[i]
             if call_on_sections:
                 try:
                     function(self, entry, **keywargs)
                 except Exception:
                     if raise_errors:
                         raise
                     else:
                         entry = self.sections[i]
                         out[entry] = False
                 # bound again in case name has changed
                 entry = self.sections[i]
             # previous result is discarded
             out[entry] = self[entry].walk(
                 function,
                 raise_errors=raise_errors,
                 call_on_sections=call_on_sections,
                 **keywargs)
         return out
     def decode(self, encoding):
         """
         Decode all strings and values to unicode, using the specified encoding.
         Works with subsections and list values.
         Uses the ``walk`` method.
         Testing ``encode`` and ``decode``.
         >>> m = ConfigObj(a)
         >>> m.decode('ascii')
         >>> def testuni(val):
         ...     for entry in val:
         ...         if not isinstance(entry, unicode):
         ...             print >> sys.stderr, type(entry)
         ...             raise AssertionError, 'decode failed.'
         ...         if isinstance(val[entry], dict):
         ...             testuni(val[entry])
         ...         elif not isinstance(val[entry], unicode):
         ...             raise AssertionError, 'decode failed.'
         >>> testuni(m)
         >>> m.encode('ascii')
         >>> a == m
 
         """
         warn('use of ``decode`` is deprecated.', DeprecationWarning)
         def decode(section, key, encoding=encoding, warn=True):
             """ """
             val = section[key]
             if isinstance(val, (list, tuple)):
                 newval = []
                 for entry in val:
                     newval.append(entry.decode(encoding))
             elif isinstance(val, dict):
                 newval = val
             else:
                 newval = val.decode(encoding)
             newkey = key.decode(encoding)
             section.rename(key, newkey)
             section[newkey] = newval
         # using ``call_on_sections`` allows us to modify section names
         self.walk(decode, call_on_sections=True)
     def encode(self, encoding):
         """
         Encode all strings and values from unicode,
         using the specified encoding.
         Works with subsections and list values.
         Uses the ``walk`` method.
         """
         warn('use of ``encode`` is deprecated.', DeprecationWarning)
         def encode(section, key, encoding=encoding):
             """ """
             val = section[key]
             if isinstance(val, (list, tuple)):
                 newval = []
                 for entry in val:
                     newval.append(entry.encode(encoding))
             elif isinstance(val, dict):
                 newval = val
             else:
                 newval = val.encode(encoding)
             newkey = key.encode(encoding)
             section.rename(key, newkey)
             section[newkey] = newval
         self.walk(encode, call_on_sections=True)
     def istrue(self, key):
         """A deprecated version of ``as_bool``."""
         warn('use of ``istrue`` is deprecated. Use ``as_bool`` method '
                 'instead.', DeprecationWarning)
         return self.as_bool(key)
     def as_bool(self, key):
         """
         Accepts a key as input. The corresponding value must be a string or
         the objects (``True`` or 1) or (``False`` or 0). We allow 0 and 1 to
         retain compatibility with Python 2.2.
         If the string is one of  ``True``, ``On``, ``Yes``, or ``1`` it returns
         ``True``.
         If the string is one of  ``False``, ``Off``, ``No``, or ``0`` it returns
         ``False``.
         ``as_bool`` is not case sensitive.
         Any other input will raise a ``ValueError``.
         >>> a = ConfigObj()
         >>> a['a'] = 'fish'
         >>> a.as_bool('a')
         Traceback (most recent call last):
         ValueError: Value "fish" is neither True nor False
         >>> a['b'] = 'True'
         >>> a.as_bool('b')
 
         >>> a['b'] = 'off'
         >>> a.as_bool('b')
 
         """
         val = self[key]
         if val == True:
             return True
         elif val == False:
             return False
         else:
             try:
                 if not isinstance(val, StringTypes):
                     raise KeyError
                 else:
                     return self.main._bools[val.lower()]
             except KeyError:
                 raise ValueError('Value "%s" is neither True nor False' % val)
     def as_int(self, key):
         """
         A convenience method which coerces the specified value to an integer.
         If the value is an invalid literal for ``int``, a ``ValueError`` will
         be raised.
         >>> a = ConfigObj()
         >>> a['a'] = 'fish'
         >>> a.as_int('a')
         Traceback (most recent call last):
         ValueError: invalid literal for int(): fish
         >>> a['b'] = '1'
         >>> a.as_int('b')
 
         >>> a['b'] = '3.2'
         >>> a.as_int('b')
         Traceback (most recent call last):
         ValueError: invalid literal for int(): 3.2
         """
         return int(self[key])
     def as_float(self, key):
         """
         A convenience method which coerces the specified value to a float.
         If the value is an invalid literal for ``float``, a ``ValueError`` will
         be raised.
         >>> a = ConfigObj()
         >>> a['a'] = 'fish'
         >>> a.as_float('a')
         Traceback (most recent call last):
         ValueError: invalid literal for float(): fish
         >>> a['b'] = '1'
         >>> a.as_float('b')
 .0
         >>> a['b'] = '3.2'
         >>> a.as_float('b')
 .2000000000000002
         """
         return float(self[key])
 class ConfigObj(Section):
     """An object to read, create, and write config files."""
     _keyword = re.compile(r'''^ # line start
         (\s*)                   # indentation
         (                       # keyword
             (?:".*?")|          # double quotes
             (?:'.*?')|          # single quotes
             (?:[^'"=].*?)       # no quotes
         )
         \s*=\s*                 # divider
         (.*)                    # value (including list values and comments)
         $   # line end
         ''',
         re.VERBOSE)
     _sectionmarker = re.compile(r'''^
         (\s*)                     # 1: indentation
         ((?:\[\s*)+)              # 2: section marker open
         (                         # 3: section name open
             (?:"\s*\S.*?\s*")|    # at least one non-space with double quotes
             (?:'\s*\S.*?\s*')|    # at least one non-space with single quotes
             (?:[^'"\s].*?)        # at least one non-space unquoted
         )                         # section name close
         ((?:\s*\])+)              # 4: section marker close
         \s*(\#.*)?                # 5: optional comment
         $''',
         re.VERBOSE)
     # this regexp pulls list values out as a single string
     # or single values and comments
     # FIXME: this regex adds a '' to the end of comma terminated lists
     #   workaround in ``_handle_value``
     _valueexp = re.compile(r'''^
         (?:
             (?:
                 (
                     (?:
                         (?:
                             (?:".*?")|              # double quotes
                             (?:'.*?')|              # single quotes
                             (?:[^'",\#][^,\#]*?)    # unquoted
                         )
                         \s*,\s*                     # comma
                     )*      # match all list items ending in a comma (if any)
                 )
                 (
                     (?:".*?")|                      # double quotes
                     (?:'.*?')|                      # single quotes
                     (?:[^'",\#\s][^,]*?)|           # unquoted
                     (?:(?<!,))                      # Empty value
                 )?          # last item in a list - or string value
             )|
             (,)             # alternatively a single comma - empty list
         )
         \s*(\#.*)?          # optional comment
         $''',
         re.VERBOSE)
     # use findall to get the members of a list value
     _listvalueexp = re.compile(r'''
         (
             (?:".*?")|          # double quotes
             (?:'.*?')|          # single quotes
             (?:[^'",\#].*?)       # unquoted
         )
         \s*,\s*                 # comma
         ''',
         re.VERBOSE)
     # this regexp is used for the value
     # when lists are switched off
     _nolistvalue = re.compile(r'''^
         (
             (?:".*?")|          # double quotes
             (?:'.*?')|          # single quotes
             (?:[^'"\#].*?)|     # unquoted
             (?:)                # Empty value
         )
         \s*(\#.*)?              # optional comment
         $''',
         re.VERBOSE)
     # regexes for finding triple quoted values on one line
     _single_line_single = re.compile(r"^'''(.*?)'''\s*(#.*)?$")
     _single_line_double = re.compile(r'^"""(.*?)"""\s*(#.*)?$')
     _multi_line_single = re.compile(r"^(.*?)'''\s*(#.*)?$")
     _multi_line_double = re.compile(r'^(.*?)"""\s*(#.*)?$')
     _triple_quote = {
         "'''": (_single_line_single, _multi_line_single),
         '"""': (_single_line_double, _multi_line_double),
     }
     # Used by the ``istrue`` Section method
     _bools = {
         'yes': True, 'no': False,
         'on': True, 'off': False,
         '1': True, '0': False,
         'true': True, 'false': False,
         }
     def __init__(self, infile=None, options=None, **kwargs):
         """
         Parse or create a config file object.
         ``ConfigObj(infile=None, options=None, **kwargs)``
         """
         if infile is None:
             infile = []
         if options is None:
             options = {}
         else:
             options = dict(options)
         # keyword arguments take precedence over an options dictionary
         options.update(kwargs)
         # init the superclass
         Section.__init__(self, self, 0, self)
         #
         defaults = OPTION_DEFAULTS.copy()
         for entry in options.keys():
             if entry not in defaults.keys():
                 raise TypeError, 'Unrecognised option "%s".' % entry
         # TODO: check the values too.
         #
         # Add any explicit options to the defaults
         defaults.update(options)
         #
         # initialise a few variables
         self.filename = None
         self._errors = []
         self.raise_errors = defaults['raise_errors']
         self.interpolation = defaults['interpolation']
         self.list_values = defaults['list_values']
         self.create_empty = defaults['create_empty']
         self.file_error = defaults['file_error']
         self.stringify = defaults['stringify']
         self.indent_type = defaults['indent_type']
         self.encoding = defaults['encoding']
         self.default_encoding = defaults['default_encoding']
         self.BOM = False
         self.newlines = None
         self.write_empty_values = defaults['write_empty_values']
         self.unrepr = defaults['unrepr']
         #
         self.initial_comment = []
         self.final_comment = []
         #
         self._terminated = False
         #
         if isinstance(infile, StringTypes):
             self.filename = infile
             if os.path.isfile(infile):
                 infile = open(infile).read() or []
             elif self.file_error:
                 # raise an error if the file doesn't exist
                 raise IOError, 'Config file not found: "%s".' % self.filename
             else:
                 # file doesn't already exist
                 if self.create_empty:
                     # this is a good test that the filename specified
                     # isn't impossible - like on a non existent device
                     h = open(infile, 'w')
                     h.write('')
                     h.close()
                 infile = []
         elif isinstance(infile, (list, tuple)):
             infile = list(infile)
         elif isinstance(infile, dict):
             # initialise self
             # the Section class handles creating subsections
             if isinstance(infile, ConfigObj):
                 # get a copy of our ConfigObj
                 infile = infile.dict()
             for entry in infile:
                 self[entry] = infile[entry]
             del self._errors
             if defaults['configspec'] is not None:
                 self._handle_configspec(defaults['configspec'])
             else:
                 self.configspec = None
             return
         elif hasattr(infile, 'read'):
             # This supports file like objects
             infile = infile.read() or []
             # needs splitting into lines - but needs doing *after* decoding
             # in case it's not an 8 bit encoding
         else:
             raise TypeError, ('infile must be a filename,'
                 ' file like object, or list of lines.')
         #
         if infile:
             # don't do it for the empty ConfigObj
             infile = self._handle_bom(infile)
             # infile is now *always* a list
             #
             # Set the newlines attribute (first line ending it finds)
             # and strip trailing '\n' or '\r' from lines
             for line in infile:
                 if (not line) or (line[-1] not in ('\r', '\n', '\r\n')):
                     continue
                 for end in ('\r\n', '\n', '\r'):
                     if line.endswith(end):
                         self.newlines = end
                         break
                 break
             if infile[-1] and infile[-1] in ('\r', '\n', '\r\n'):
                 self._terminated = True
             infile = [line.rstrip('\r\n') for line in infile]
         #
         self._parse(infile)
         # if we had any errors, now is the time to raise them
         if self._errors:
             info = "at line %s." % self._errors[0].line_number
             if len(self._errors) > 1:
                 msg = ("Parsing failed with several errors.\nFirst error %s" %
                     info)
                 error = ConfigObjError(msg)
             else:
                 error = self._errors[0]
             # set the errors attribute; it's a list of tuples:
             # (error_type, message, line_number)
             error.errors = self._errors
             # set the config attribute
             error.config = self
             raise error
         # delete private attributes
         del self._errors
         #
         if defaults['configspec'] is None:
             self.configspec = None
         else:
             self._handle_configspec(defaults['configspec'])
     def __repr__(self):
         return 'ConfigObj({%s})' % ', '.join(
             [('%s: %s' % (repr(key), repr(self[key]))) for key in
             (self.scalars + self.sections)])
     def _handle_bom(self, infile):
         """
         Handle any BOM, and decode if necessary.
         If an encoding is specified, that *must* be used - but the BOM should
         still be removed (and the BOM attribute set).
         (If the encoding is wrongly specified, then a BOM for an alternative
         encoding won't be discovered or removed.)
         If an encoding is not specified, UTF8 or UTF16 BOM will be detected and
         removed. The BOM attribute will be set. UTF16 will be decoded to
         unicode.
         NOTE: This method must not be called with an empty ``infile``.
         Specifying the *wrong* encoding is likely to cause a
         ``UnicodeDecodeError``.
         ``infile`` must always be returned as a list of lines, but may be
         passed in as a single string.
         """
         if ((self.encoding is not None) and
             (self.encoding.lower() not in BOM_LIST)):
             # No need to check for a BOM
             # the encoding specified doesn't have one
             # just decode
             return self._decode(infile, self.encoding)
         #
         if isinstance(infile, (list, tuple)):
             line = infile[0]
         else:
             line = infile
         if self.encoding is not None:
             # encoding explicitly supplied
             # And it could have an associated BOM
             # TODO: if encoding is just UTF16 - we ought to check for both
             # TODO: big endian and little endian versions.
             enc = BOM_LIST[self.encoding.lower()]
             if enc == 'utf_16':
                 # For UTF16 we try big endian and little endian
                 for BOM, (encoding, final_encoding) in BOMS.items():
                     if not final_encoding:
                         # skip UTF8
                         continue
                     if infile.startswith(BOM):
                         ### BOM discovered
                         ##self.BOM = True
                         # Don't need to remove BOM
                         return self._decode(infile, encoding)
                 #
                 # If we get this far, will *probably* raise a DecodeError
                 # As it doesn't appear to start with a BOM
                 return self._decode(infile, self.encoding)
             #
             # Must be UTF8
             BOM = BOM_SET[enc]
             if not line.startswith(BOM):
                 return self._decode(infile, self.encoding)
             #
             newline = line[len(BOM):]
             #
             # BOM removed
             if isinstance(infile, (list, tuple)):
                 infile[0] = newline
             else:
                 infile = newline
             self.BOM = True
             return self._decode(infile, self.encoding)
         #
         # No encoding specified - so we need to check for UTF8/UTF16
         for BOM, (encoding, final_encoding) in BOMS.items():
             if not line.startswith(BOM):
                 continue
             else:
                 # BOM discovered
                 self.encoding = final_encoding
                 if not final_encoding:
                     self.BOM = True
                     # UTF8
                     # remove BOM
                     newline = line[len(BOM):]
                     if isinstance(infile, (list, tuple)):
                         infile[0] = newline
                     else:
                         infile = newline
                     # UTF8 - don't decode
                     if isinstance(infile, StringTypes):
                         return infile.splitlines(True)
                     else:
                         return infile
                 # UTF16 - have to decode
                 return self._decode(infile, encoding)
         #
         # No BOM discovered and no encoding specified, just return
         if isinstance(infile, StringTypes):
             # infile read from a file will be a single string
             return infile.splitlines(True)
         else:
             return infile
     def _a_to_u(self, aString):
         """Decode ASCII strings to unicode if a self.encoding is specified."""
         if self.encoding:
             return aString.decode('ascii')
         else:
             return aString
     def _decode(self, infile, encoding):
         """
         Decode infile to unicode. Using the specified encoding.
         if is a string, it also needs converting to a list.
         """
         if isinstance(infile, StringTypes):
             # can't be unicode
             # NOTE: Could raise a ``UnicodeDecodeError``
             return infile.decode(encoding).splitlines(True)
         for i, line in enumerate(infile):
             if not isinstance(line, unicode):
                 # NOTE: The isinstance test here handles mixed lists of unicode/string
                 # NOTE: But the decode will break on any non-string values
                 # NOTE: Or could raise a ``UnicodeDecodeError``
                 infile[i] = line.decode(encoding)
         return infile
     def _decode_element(self, line):
         """Decode element to unicode if necessary."""
         if not self.encoding:
             return line
         if isinstance(line, str) and self.default_encoding:
             return line.decode(self.default_encoding)
         return line
     def _str(self, value):
         """
         Used by ``stringify`` within validate, to turn non-string values
         into strings.
         """
         if not isinstance(value, StringTypes):
             return str(value)
         else:
             return value
     def _parse(self, infile):
         """Actually parse the config file."""
         temp_list_values = self.list_values
         if self.unrepr:
             self.list_values = False
         comment_list = []
         done_start = False
         this_section = self
         maxline = len(infile) - 1
         cur_index = -1
         reset_comment = False
         while cur_index < maxline:
             if reset_comment:
                 comment_list = []
             cur_index += 1
             line = infile[cur_index]
             sline = line.strip()
             # do we have anything on the line ?
             if not sline or sline.startswith('#') or sline.startswith(';'):
                 reset_comment = False
                 comment_list.append(line)
                 continue
             if not done_start:
                 # preserve initial comment
                 self.initial_comment = comment_list
                 comment_list = []
                 done_start = True
             reset_comment = True
             # first we check if it's a section marker
             mat = self._sectionmarker.match(line)
             if mat is not None:
                 # is a section line
                 (indent, sect_open, sect_name, sect_close, comment) = (
                     mat.groups())
                 if indent and (self.indent_type is None):
                     self.indent_type = indent
                 cur_depth = sect_open.count('[')
                 if cur_depth != sect_close.count(']'):
                     self._handle_error(
                         "Cannot compute the section depth at line %s.",
                         NestingError, infile, cur_index)
                     continue
                 #
                 if cur_depth < this_section.depth:
                     # the new section is dropping back to a previous level
                     try:
                         parent = self._match_depth(
                             this_section,
                             cur_depth).parent
                     except SyntaxError:
                         self._handle_error(
                             "Cannot compute nesting level at line %s.",
                             NestingError, infile, cur_index)
                         continue
                 elif cur_depth == this_section.depth:
                     # the new section is a sibling of the current section
                     parent = this_section.parent
                 elif cur_depth == this_section.depth + 1:
                     # the new section is a child the current section
                     parent = this_section
                 else:
                     self._handle_error(
                         "Section too nested at line %s.",
                         NestingError, infile, cur_index)
                 #
                 sect_name = self._unquote(sect_name)
                 if parent.has_key(sect_name):
                     self._handle_error(
                         'Duplicate section name at line %s.',
                         DuplicateError, infile, cur_index)
                     continue
                 # create the new section
                 this_section = Section(
                     parent,
                     cur_depth,
                     self,
                     name=sect_name)
                 parent[sect_name] = this_section
                 parent.inline_comments[sect_name] = comment
                 parent.comments[sect_name] = comment_list
                 continue
             #
             # it's not a section marker,
             # so it should be a valid ``key = value`` line
             mat = self._keyword.match(line)
             if mat is None:
                 # it neither matched as a keyword
                 # or a section marker
                 self._handle_error(
                     'Invalid line at line "%s".',
                     ParseError, infile, cur_index)
             else:
                 # is a keyword value
                 # value will include any inline comment
                 (indent, key, value) = mat.groups()
                 if indent and (self.indent_type is None):
                     self.indent_type = indent
                 # check for a multiline value
                 if value[:3] in ['"""', "'''"]:
                     try:
                         (value, comment, cur_index) = self._multiline(
                             value, infile, cur_index, maxline)
                     except SyntaxError:
                         self._handle_error(
                             'Parse error in value at line %s.',
                             ParseError, infile, cur_index)
                         continue
                     else:
                         if self.unrepr:
                             comment = ''
                             try:
                                 value = unrepr(value)
                             except Exception, e:
                                 if type(e) == UnknownType:
                                     msg = 'Unknown name or type in value at line %s.'
                                 else:
                                     msg = 'Parse error in value at line %s.'
                                 self._handle_error(msg, UnreprError, infile,
                                     cur_index)
                                 continue
                 else:
                     if self.unrepr:
                         comment = ''
                         try:
                             value = unrepr(value)
                         except Exception, e:
                             if isinstance(e, UnknownType):
                                 msg = 'Unknown name or type in value at line %s.'
                             else:
                                 msg = 'Parse error in value at line %s.'
                             self._handle_error(msg, UnreprError, infile,
                                 cur_index)
                             continue
                     else:
                         # extract comment and lists
                         try:
                             (value, comment) = self._handle_value(value)
                         except SyntaxError:
                             self._handle_error(
                                 'Parse error in value at line %s.',
                                 ParseError, infile, cur_index)
                             continue
                 #
                 key = self._unquote(key)
                 if this_section.has_key(key):
                     self._handle_error(
                         'Duplicate keyword name at line %s.',
                         DuplicateError, infile, cur_index)
                     continue
                 # add the key.
                 # we set unrepr because if we have got this far we will never
                 # be creating a new section
                 this_section.__setitem__(key, value, unrepr=True)
                 this_section.inline_comments[key] = comment
                 this_section.comments[key] = comment_list
                 continue
         #
         if self.indent_type is None:
             # no indentation used, set the type accordingly
             self.indent_type = ''
         #
         if self._terminated:
             comment_list.append('')
         # preserve the final comment
         if not self and not self.initial_comment:
             self.initial_comment = comment_list
         elif not reset_comment:
             self.final_comment = comment_list
         self.list_values = temp_list_values
     def _match_depth(self, sect, depth):
         """
         Given a section and a depth level, walk back through the sections
         parents to see if the depth level matches a previous section.
         Return a reference to the right section,
         or raise a SyntaxError.
         """
         while depth < sect.depth:
             if sect is sect.parent:
                 # we've reached the top level already
                 raise SyntaxError
             sect = sect.parent
         if sect.depth == depth:
             return sect
         # shouldn't get here
         raise SyntaxError
     def _handle_error(self, text, ErrorClass, infile, cur_index):
         """
         Handle an error according to the error settings.
         Either raise the error or store it.
         The error will have occurred at ``cur_index``
         """
         line = infile[cur_index]
         cur_index += 1
         message = text % cur_index
         error = ErrorClass(message, cur_index, line)
         if self.raise_errors:
             # raise the error - parsing stops here
             raise error
         # store the error
         # reraise when parsing has finished
         self._errors.append(error)
     def _unquote(self, value):
         """Return an unquoted version of a value"""
         if (value[0] == value[-1]) and (value[0] in ('"', "'")):
             value = value[1:-1]
         return value
     def _quote(self, value, multiline=True):
         """
         Return a safely quoted version of a value.
         Raise a ConfigObjError if the value cannot be safely quoted.
         If multiline is ``True`` (default) then use triple quotes
         if necessary.
         Don't quote values that don't need it.
         Recursively quote members of a list and return a comma joined list.
         Multiline is ``False`` for lists.
         Obey list syntax for empty and single member lists.
         If ``list_values=False`` then the value is only quoted if it contains
         a ``\n`` (is multiline).
         If ``write_empty_values`` is set, and the value is an empty string, it
         won't be quoted.
         """
         if multiline and self.write_empty_values and value == '':
             # Only if multiline is set, so that it is used for values not
             # keys, and not values that are part of a list
             return ''
         if multiline and isinstance(value, (list, tuple)):
             if not value:
                 return ','
             elif len(value) == 1:
                 return self._quote(value[0], multiline=False) + ','
             return ', '.join([self._quote(val, multiline=False)
                 for val in value])
         if not isinstance(value, StringTypes):
             if self.stringify:
                 value = str(value)
             else:
                 raise TypeError, 'Value "%s" is not a string.' % value
         squot = "'%s'"
         dquot = '"%s"'
         noquot = "%s"
         wspace_plus = ' \r\t\n\v\t\'"'
         tsquot = '"""%s"""'
         tdquot = "'''%s'''"
         if not value:
             return '""'
         if (not self.list_values and '\n' not in value) or not (multiline and
                 ((("'" in value) and ('"' in value)) or ('\n' in value))):
             if not self.list_values:
                 # we don't quote if ``list_values=False``
                 quot = noquot
             # for normal values either single or double quotes will do
             elif '\n' in value:
                 # will only happen if multiline is off - e.g. '\n' in key
                 raise ConfigObjError, ('Value "%s" cannot be safely quoted.' %
                     value)
             elif ((value[0] not in wspace_plus) and
                     (value[-1] not in wspace_plus) and
                     (',' not in value)):
                 quot = noquot
             else:
                 if ("'" in value) and ('"' in value):
                     raise ConfigObjError, (
                         'Value "%s" cannot be safely quoted.' % value)
                 elif '"' in value:
                     quot = squot
                 else:
                     quot = dquot
         else:
             # if value has '\n' or "'" *and* '"', it will need triple quotes
             if (value.find('"""') != -1) and (value.find("'''") != -1):
                 raise ConfigObjError, (
                     'Value "%s" cannot be safely quoted.' % value)
             if value.find('"""') == -1:
                 quot = tdquot
             else:
                 quot = tsquot
         return quot % value
     def _handle_value(self, value):
         """
         Given a value string, unquote, remove comment,
         handle lists. (including empty and single member lists)
         """
         # do we look for lists in values ?
         if not self.list_values:
             mat = self._nolistvalue.match(value)
             if mat is None:
                 raise SyntaxError
             # NOTE: we don't unquote here
             return mat.groups()
         #
         mat = self._valueexp.match(value)
         if mat is None:
             # the value is badly constructed, probably badly quoted,
             # or an invalid list
             raise SyntaxError
         (list_values, single, empty_list, comment) = mat.groups()
         if (list_values == '') and (single is None):
             # change this if you want to accept empty values
             raise SyntaxError
         # NOTE: note there is no error handling from here if the regex
         # is wrong: then incorrect values will slip through
         if empty_list is not None:
             # the single comma - meaning an empty list
             return ([], comment)
         if single is not None:
             # handle empty values
             if list_values and not single:
                 # FIXME: the '' is a workaround because our regex now matches
                 #   '' at the end of a list if it has a trailing comma
                 single = None
             else:
                 single = single or '""'
                 single = self._unquote(single)
         if list_values == '':
             # not a list value
             return (single, comment)
         the_list = self._listvalueexp.findall(list_values)
         the_list = [self._unquote(val) for val in the_list]
         if single is not None:
             the_list += [single]
         return (the_list, comment)
     def _multiline(self, value, infile, cur_index, maxline):
         """Extract the value, where we are in a multiline situation."""
         quot = value[:3]
         newvalue = value[3:]
         single_line = self._triple_quote[quot][0]
         multi_line = self._triple_quote[quot][1]
         mat = single_line.match(value)
         if mat is not None:
             retval = list(mat.groups())
             retval.append(cur_index)
             return retval
         elif newvalue.find(quot) != -1:
             # somehow the triple quote is missing
             raise SyntaxError
         #
         while cur_index < maxline:
             cur_index += 1
             newvalue += '\n'
             line = infile[cur_index]
             if line.find(quot) == -1:
                 newvalue += line
             else:
                 # end of multiline, process it
                 break
         else:
             # we've got to the end of the config, oops...
             raise SyntaxError
         mat = multi_line.match(line)
         if mat is None:
             # a badly formed line
             raise SyntaxError
         (value, comment) = mat.groups()
         return (newvalue + value, comment, cur_index)
     def _handle_configspec(self, configspec):
         """Parse the configspec."""
         # FIXME: Should we check that the configspec was created with the
         #   correct settings ? (i.e. ``list_values=False``)
         if not isinstance(configspec, ConfigObj):
             try:
                 configspec = ConfigObj(
                     configspec,
                     raise_errors=True,
                     file_error=True,
                     list_values=False)
             except ConfigObjError, e:
                 # FIXME: Should these errors have a reference
                 # to the already parsed ConfigObj ?
                 raise ConfigspecError('Parsing configspec failed: %s' % e)
             except IOError, e:
                 raise IOError('Reading configspec failed: %s' % e)
         self._set_configspec_value(configspec, self)
     def _set_configspec_value(self, configspec, section):
         """Used to recursively set configspec values."""
         if '__many__' in configspec.sections:
             section.configspec['__many__'] = configspec['__many__']
             if len(configspec.sections) > 1:
                 # FIXME: can we supply any useful information here ?
                 raise RepeatSectionError
         if hasattr(configspec, 'initial_comment'):
             section._configspec_initial_comment = configspec.initial_comment
             section._configspec_final_comment = configspec.final_comment
             section._configspec_encoding = configspec.encoding
             section._configspec_BOM = configspec.BOM
             section._configspec_newlines = configspec.newlines
             section._configspec_indent_type = configspec.indent_type
         for entry in configspec.scalars:
             section._configspec_comments[entry] = configspec.comments[entry]
             section._configspec_inline_comments[entry] = (
                 configspec.inline_comments[entry])
             section.configspec[entry] = configspec[entry]
             section._order.append(entry)
         for entry in configspec.sections:
             if entry == '__many__':
                 continue
             section._cs_section_comments[entry] = configspec.comments[entry]
             section._cs_section_inline_comments[entry] = (
                 configspec.inline_comments[entry])
             if not section.has_key(entry):
                 section[entry] = {}
             self._set_configspec_value(configspec[entry], section[entry])
     def _handle_repeat(self, section, configspec):
         """Dynamically assign configspec for repeated section."""
         try:
             section_keys = configspec.sections
             scalar_keys = configspec.scalars
         except AttributeError:
             section_keys = [entry for entry in configspec
                                 if isinstance(configspec[entry], dict)]
             scalar_keys = [entry for entry in configspec
                                 if not isinstance(configspec[entry], dict)]
         if '__many__' in section_keys and len(section_keys) > 1:
             # FIXME: can we supply any useful information here ?
             raise RepeatSectionError
         scalars = {}
         sections = {}
         for entry in scalar_keys:
             val = configspec[entry]
             scalars[entry] = val
         for entry in section_keys:
             val = configspec[entry]
             if entry == '__many__':
                 scalars[entry] = val
                 continue
             sections[entry] = val
         #
         section.configspec = scalars
         for entry in sections:
             if not section.has_key(entry):
                 section[entry] = {}
             self._handle_repeat(section[entry], sections[entry])
     def _write_line(self, indent_string, entry, this_entry, comment):
         """Write an individual line, for the write method"""
         # NOTE: the calls to self._quote here handles non-StringType values.
         if not self.unrepr:
             val = self._decode_element(self._quote(this_entry))
         else:
             val = repr(this_entry)
         return '%s%s%s%s%s' % (
             indent_string,
             self._decode_element(self._quote(entry, multiline=False)),
             self._a_to_u(' = '),
             val,
             self._decode_element(comment))
     def _write_marker(self, indent_string, depth, entry, comment):
         """Write a section marker line"""
         return '%s%s%s%s%s' % (
             indent_string,
             self._a_to_u('[' * depth),
             self._quote(self._decode_element(entry), multiline=False),
             self._a_to_u(']' * depth),
             self._decode_element(comment))
     def _handle_comment(self, comment):
         """Deal with a comment."""
         if not comment:
             return ''
         start = self.indent_type
         if not comment.startswith('#'):
             start += self._a_to_u(' # ')
         return (start + comment)
     # Public methods
     def write(self, outfile=None, section=None):
         """
         Write the current ConfigObj as a file
         tekNico: FIXME: use StringIO instead of real files
         >>> filename = a.filename
         >>> a.filename = 'test.ini'
         >>> a.write()
         >>> a.filename = filename
         >>> a == ConfigObj('test.ini', raise_errors=True)
 
         """
         if self.indent_type is None:
             # this can be true if initialised from a dictionary
             self.indent_type = DEFAULT_INDENT_TYPE
         #
         out = []
         cs = self._a_to_u('#')
         csp = self._a_to_u('# ')
         if section is None:
             int_val = self.interpolation
             self.interpolation = False
             section = self
             for line in self.initial_comment:
                 line = self._decode_element(line)
                 stripped_line = line.strip()
                 if stripped_line and not stripped_line.startswith(cs):
                     line = csp + line
                 out.append(line)
         #
         indent_string = self.indent_type * section.depth
         for entry in (section.scalars + section.sections):
             if entry in section.defaults:
                 # don't write out default values
                 continue
             for comment_line in section.comments[entry]:
                 comment_line = self._decode_element(comment_line.lstrip())
                 if comment_line and not comment_line.startswith(cs):
                     comment_line = csp + comment_line
                 out.append(indent_string + comment_line)
             this_entry = section[entry]
             comment = self._handle_comment(section.inline_comments[entry])
             #
             if isinstance(this_entry, dict):
                 # a section
                 out.append(self._write_marker(
                     indent_string,
                     this_entry.depth,
                     entry,
                     comment))
                 out.extend(self.write(section=this_entry))
             else:
                 out.append(self._write_line(
                     indent_string,
                     entry,
                     this_entry,
                     comment))
         #
         if section is self:
             for line in self.final_comment:
                 line = self._decode_element(line)
                 stripped_line = line.strip()
                 if stripped_line and not stripped_line.startswith(cs):
                     line = csp + line
                 out.append(line)
             self.interpolation = int_val
         #
         if section is not self:
             return out
         #
         if (self.filename is None) and (outfile is None):
             # output a list of lines
             # might need to encode
             # NOTE: This will *screw* UTF16, each line will start with the BOM
             if self.encoding:
                 out = [l.encode(self.encoding) for l in out]
             if (self.BOM and ((self.encoding is None) or
                 (BOM_LIST.get(self.encoding.lower()) == 'utf_8'))):
                 # Add the UTF8 BOM
                 if not out:
                     out.append('')
                 out[0] = BOM_UTF8 + out[0]
             return out
         #
         # Turn the list to a string, joined with correct newlines
         output = (self._a_to_u(self.newlines or os.linesep)
             ).join(out)
         if self.encoding:
             output = output.encode(self.encoding)
         if (self.BOM and ((self.encoding is None) or
             (BOM_LIST.get(self.encoding.lower()) == 'utf_8'))):
             # Add the UTF8 BOM
             output = BOM_UTF8 + output
         if outfile is not None:
             outfile.write(output)
         else:
             h = open(self.filename, 'wb')
             h.write(output)
             h.close()
     def validate(self, validator, preserve_errors=False, copy=False,
         section=None):
         """
         Test the ConfigObj against a configspec.
         It uses the ``validator`` object from *validate.py*.
         To run ``validate`` on the current ConfigObj, call: ::
             test = config.validate(validator)
         (Normally having previously passed in the configspec when the ConfigObj
         was created - you can dynamically assign a dictionary of checks to the
         ``configspec`` attribute of a section though).
         It returns ``True`` if everything passes, or a dictionary of
         pass/fails (True/False). If every member of a subsection passes, it
         will just have the value ``True``. (It also returns ``False`` if all
         members fail).
         In addition, it converts the values from strings to their native
         types if their checks pass (and ``stringify`` is set).
         If ``preserve_errors`` is ``True`` (``False`` is default) then instead
         of a marking a fail with a ``False``, it will preserve the actual
         exception object. This can contain info about the reason for failure.
         For example the ``VdtValueTooSmallError`` indeicates that the value
         supplied was too small. If a value (or section) is missing it will
         still be marked as ``False``.
         You must have the validate module to use ``preserve_errors=True``.
         You can then use the ``flatten_errors`` function to turn your nested
         results dictionary into a flattened list of failures - useful for
         displaying meaningful error messages.
         """
         if section is None:
             if self.configspec is None:
                 raise ValueError, 'No configspec supplied.'
             if preserve_errors:
                 if VdtMissingValue is None:
                     raise ImportError('Missing validate module.')
             section = self
         #
         spec_section = section.configspec
         if copy and hasattr(section, '_configspec_initial_comment'):
             section.initial_comment = section._configspec_initial_comment
             section.final_comment = section._configspec_final_comment
             section.encoding = section._configspec_encoding
             section.BOM = section._configspec_BOM
             section.newlines = section._configspec_newlines
             section.indent_type = section._configspec_indent_type
         if '__many__' in section.configspec:
             many = spec_section['__many__']
             # dynamically assign the configspecs
             # for the sections below
             for entry in section.sections:
                 self._handle_repeat(section[entry], many)
         #
         out = {}
         ret_true = True
         ret_false = True
         order = [k for k in section._order if k in spec_section]
         order += [k for k in spec_section if k not in order]
         for entry in order:
             if entry == '__many__':
                 continue
             if (not entry in section.scalars) or (entry in section.defaults):
                 # missing entries
                 # or entries from defaults
                 missing = True
                 val = None
                 if copy and not entry in section.scalars:
                     # copy comments
                     section.comments[entry] = (
                         section._configspec_comments.get(entry, []))
                     section.inline_comments[entry] = (
                         section._configspec_inline_comments.get(entry, ''))
                 #
             else:
                 missing = False
                 val = section[entry]
             try:
                 check = validator.check(spec_section[entry],
                                         val,
                                         missing=missing
                                         )
             except validator.baseErrorClass, e:
                 if not preserve_errors or isinstance(e, VdtMissingValue):
                     out[entry] = False
                 else:
                     # preserve the error
                     out[entry] = e
                     ret_false = False
                 ret_true = False
             else:
                 ret_false = False
                 out[entry] = True
                 if self.stringify or missing:
                     # if we are doing type conversion
                     # or the value is a supplied default
                     if not self.stringify:
                         if isinstance(check, (list, tuple)):
                             # preserve lists
                             check = [self._str(item) for item in check]
                         elif missing and check is None:
                             # convert the None from a default to a ''
                             check = ''
                         else:
                             check = self._str(check)
                     if (check != val) or missing:
                         section[entry] = check
                 if not copy and missing and entry not in section.defaults:
                     section.defaults.append(entry)
         #
         # Missing sections will have been created as empty ones when the
         # configspec was read.
         for entry in section.sections:
             # FIXME: this means DEFAULT is not copied in copy mode
             if section is self and entry == 'DEFAULT':
                 continue
             if copy:
                 section.comments[entry] = section._cs_section_comments[entry]
                 section.inline_comments[entry] = (
                     section._cs_section_inline_comments[entry])
             check = self.validate(validator, preserve_errors=preserve_errors,
                 copy=copy, section=section[entry])
             out[entry] = check
             if check == False:
                 ret_true = False
             elif check == True:
                 ret_false = False
             else:
                 ret_true = False
                 ret_false = False
         #
         if ret_true:
             return True
         elif ret_false:
             return False
         else:
             return out
 class SimpleVal(object):
     """
     A simple validator.
     Can be used to check that all members expected are present.
     To use it, provide a configspec with all your members in (the value given
     will be ignored). Pass an instance of ``SimpleVal`` to the ``validate``
     method of your ``ConfigObj``. ``validate`` will return ``True`` if all
     members are present, or a dictionary with True/False meaning
     present/missing. (Whole missing sections will be replaced with ``False``)
     """
     def __init__(self):
         self.baseErrorClass = ConfigObjError
     def check(self, check, member, missing=False):
         """A dummy check method, always returns the value unchanged."""
         if missing:
             raise self.baseErrorClass
         return member
 # Check / processing functions for options
 def flatten_errors(cfg, res, levels=None, results=None):
     """
     An example function that will turn a nested dictionary of results
     (as returned by ``ConfigObj.validate``) into a flat list.
     ``cfg`` is the ConfigObj instance being checked, ``res`` is the results
     dictionary returned by ``validate``.
     (This is a recursive function, so you shouldn't use the ``levels`` or
     ``results`` arguments - they are used by the function.
     Returns a list of keys that failed. Each member of the list is a tuple :
     ::
         ([list of sections...], key, result)
     If ``validate`` was called with ``preserve_errors=False`` (the default)
     then ``result`` will always be ``False``.
     *list of sections* is a flattened list of sections that the key was found
     in.
     If the section was missing then key will be ``None``.
     If the value (or section) was missing then ``result`` will be ``False``.
     If ``validate`` was called with ``preserve_errors=True`` and a value
     was present, but failed the check, then ``result`` will be the exception
     object returned. You can use this as a string that describes the failure.
     For example *The value "3" is of the wrong type*.
     >>> import validate
     >>> vtor = validate.Validator()
     >>> my_ini = '''
     ...     option1 = True
     ...     [section1]
     ...     option1 = True
     ...     [section2]
     ...     another_option = Probably
     ...     [section3]
     ...     another_option = True
     ...     [[section3b]]
     ...     value = 3
     ...     value2 = a
     ...     value3 = 11
     ...     '''
     >>> my_cfg = '''
     ...     option1 = boolean()
     ...     option2 = boolean()
     ...     option3 = boolean(default=Bad_value)
     ...     [section1]
     ...     option1 = boolean()
     ...     option2 = boolean()
     ...     option3 = boolean(default=Bad_value)
     ...     [section2]
     ...     another_option = boolean()
     ...     [section3]
     ...     another_option = boolean()
     ...     [[section3b]]
     ...     value = integer
     ...     value2 = integer
     ...     value3 = integer(0, 10)
     ...         [[[section3b-sub]]]
     ...         value = string
     ...     [section4]
     ...     another_option = boolean()
     ...     '''
     >>> cs = my_cfg.split('\\n')
     >>> ini = my_ini.split('\\n')
     >>> cfg = ConfigObj(ini, configspec=cs)
     >>> res = cfg.validate(vtor, preserve_errors=True)
     >>> errors = []
     >>> for entry in flatten_errors(cfg, res):
     ...     section_list, key, error = entry
     ...     section_list.insert(0, '[root]')
     ...     if key is not None:
     ...        section_list.append(key)
     ...     else:
     ...         section_list.append('[missing]')
     ...     section_string = ', '.join(section_list)
     ...     errors.append((section_string, ' = ', error))
     >>> errors.sort()
     >>> for entry in errors:
     ...     print entry[0], entry[1], (entry[2] or 0)
     [root], option2  =  0
     [root], option3  =  the value "Bad_value" is of the wrong type.
     [root], section1, option2  =  0
     [root], section1, option3  =  the value "Bad_value" is of the wrong type.
     [root], section2, another_option  =  the value "Probably" is of the wrong type.
     [root], section3, section3b, section3b-sub, [missing]  =  0
     [root], section3, section3b, value2  =  the value "a" is of the wrong type.
     [root], section3, section3b, value3  =  the value "11" is too big.
     [root], section4, [missing]  =  0
     """
     if levels is None:
         # first time called
         levels = []
         results = []
     if res is True:
         return results
     if res is False:
         results.append((levels[:], None, False))
         if levels:
             levels.pop()
         return results
     for (key, val) in res.items():
         if val == True:
             continue
         if isinstance(cfg.get(key), dict):
             # Go down one level
             levels.append(key)
             flatten_errors(cfg[key], val, levels, results)
             continue
         results.append((levels[:], key, val))
     #
     # Go up one level
     if levels:
         levels.pop()
     #
     return results
 """*A programming language is a medium of expression.* - Paul Graham"""

The Tor Browser / annotate

config/configobj.py@97036ab72558 (annotated)

config/configobj.py