"""Configuration file parser.

A configuration file consists of sections, lead by a "[section]" header,
and followed by "name: value" entries, with continuations and such in
the style of RFC 822.

Intrinsic defaults can be specified by passing them into the
ConfigParser constructor as a dictionary.

class:

ConfigParser -- responsible for parsing a list of
 configuration files, and managing the parsed database.

 methods:

 __init__(defaults=None, dict_type=_default_dict, allow_no_value=False,
 delimiters=('=', ':'), comment_prefixes=('#', ';'),
 inline_comment_prefixes=None, strict=True,
 empty_lines_in_values=True, default_section='DEFAULT',
 interpolation=<unset>, converters=<unset>):
 Create the parser. When `defaults' is given, it is initialized into the
 dictionary or intrinsic defaults. The keys must be strings, the values
 must be appropriate for %()s string interpolation.

 When `dict_type' is given, it will be used to create the dictionary
 objects for the list of sections, for the options within a section, and
 for the default values.

 When `delimiters' is given, it will be used as the set of substrings
 that divide keys from values.

 When `comment_prefixes' is given, it will be used as the set of
 substrings that prefix comments in empty lines. Comments can be
 indented.

 When `inline_comment_prefixes' is given, it will be used as the set of
 substrings that prefix comments in non-empty lines.

 When `strict` is True, the parser won't allow for any section or option
 duplicates while reading from a single source (file, string or
 dictionary). Default is True.

 When `empty_lines_in_values' is False (default: True), each empty line
 marks the end of an option. Otherwise, internal empty lines of
 a multiline option are kept as part of the value.

 When `allow_no_value' is True (default: False), options without
 values are accepted; the value presented for these is None.

 When `default_section' is given, the name of the special section is
 named accordingly. By default it is called ``"DEFAULT"`` but this can
 be customized to point to any other valid section name. Its current
 value can be retrieved using the ``parser_instance.default_section``
 attribute and may be modified at runtime.

 When `interpolation` is given, it should be an Interpolation subclass
 instance. It will be used as the handler for option value
 pre-processing when using getters. RawConfigParser objects don't do
 any sort of interpolation, whereas ConfigParser uses an instance of
 BasicInterpolation. The library also provides a ``zc.buildbot``
 inspired ExtendedInterpolation implementation.

 When `converters` is given, it should be a dictionary where each key
 represents the name of a type converter and each value is a callable
 implementing the conversion from string to the desired datatype. Every
 converter gets its corresponding get*() method on the parser object and
 section proxies.

 sections()
 Return all the configuration section names, sans DEFAULT.

 has_section(section)
 Return whether the given section exists.

 has_option(section, option)
 Return whether the given option exists in the given section.

 options(section)
 Return list of configuration options for the named section.

 read(filenames, encoding=None)
 Read and parse the iterable of named configuration files, given by
 name. A single filename is also allowed. Non-existing files
 are ignored. Return list of successfully read files.

 read_file(f, filename=None)
 Read and parse one configuration file, given as a file object.
 The filename defaults to f.name; it is only used in error
 messages (if f has no `name' attribute, the string `<???>' is used).

 read_string(string)
 Read configuration from a given string.

 read_dict(dictionary)
 Read configuration from a dictionary. Keys are section names,
 values are dictionaries with keys and values that should be present
 in the section. If the used dictionary type preserves order, sections
 and their keys will be added in order. Values are automatically
 converted to strings.

 get(section, option, raw=False, vars=None, fallback=_UNSET)
 Return a string value for the named option. All % interpolations are
 expanded in the return values, based on the defaults passed into the
 constructor and the DEFAULT section. Additional substitutions may be
 provided using the `vars' argument, which must be a dictionary whose
 contents override any pre-existing defaults. If `option' is a key in
 `vars', the value from `vars' is used.

 getint(section, options, raw=False, vars=None, fallback=_UNSET)
 Like get(), but convert value to an integer.

 getfloat(section, options, raw=False, vars=None, fallback=_UNSET)
 Like get(), but convert value to a float.

 getboolean(section, options, raw=False, vars=None, fallback=_UNSET)
 Like get(), but convert value to a boolean (currently case
 insensitively defined as 0, false, no, off for False, and 1, true,
 yes, on for True). Returns False or True.

 items(section=_UNSET, raw=False, vars=None)
 If section is given, return a list of tuples with (name, value) for
 each option in the section. Otherwise, return a list of tuples with
 (section_name, section_proxy) for each section, including DEFAULTSECT.

 remove_section(section)
 Remove the given file section and all its options.

 remove_option(section, option)
 Remove the given option from the given section.

 set(section, option, value)
 Set the given option.

 write(fp, space_around_delimiters=True)
 Write the configuration state in .ini format. If
 `space_around_delimiters' is True (the default), delimiters
 between keys and values are surrounded by spaces.
"""

from collections.abc import MutableMapping
from collections import ChainMap as _ChainMap
import functools
import io
import itertools
import os
import re
import sys
import warnings

__all__ = ["NoSectionError", "DuplicateOptionError", "DuplicateSectionError",
 "NoOptionError", "InterpolationError", "InterpolationDepthError",
 "InterpolationMissingOptionError", "InterpolationSyntaxError",
 "ParsingError", "MissingSectionHeaderError",
 "ConfigParser", "SafeConfigParser", "RawConfigParser",
 "Interpolation", "BasicInterpolation", "ExtendedInterpolation",
 "LegacyInterpolation", "SectionProxy", "ConverterMapping",
 "DEFAULTSECT", "MAX_INTERPOLATION_DEPTH"]

_default_dict = dict
DEFAULTSECT = "DEFAULT"

MAX_INTERPOLATION_DEPTH = 10



# exception classes
class Error(Exception):
 """Base class for ConfigParser exceptions."""

 def __init__(self, msg=''):
 self.message = msg
 Exception.__init__(self, msg)

 def __repr__(self):
 return self.message

 __str__ = __repr__


class NoSectionError(Error):
 """Raised when no section matches a requested option."""

 def __init__(self, section):
 Error.__init__(self, 'No section: %r' % (section,))
 self.section = section
 self.args = (section, )


class DuplicateSectionError(Error):
 """Raised when a section is repeated in an input source.

 Possible repetitions that raise this exception are: multiple creation
 using the API or in strict parsers when a section is found more than once
 in a single input file, string or dictionary.
 """

 def __init__(self, section, source=None, lineno=None):
 msg = [repr(section), " already exists"]
 if source is not None:
 message = ["While reading from ", repr(source)]
 if lineno is not None:
 message.append(" [line {0:2d}]".format(lineno))
 message.append(": section ")
 message.extend(msg)
 msg = message
 else:
 msg.insert(0, "Section ")
 Error.__init__(self, "".join(msg))
 self.section = section
 self.source = source
 self.lineno = lineno
 self.args = (section, source, lineno)


class DuplicateOptionError(Error):
 """Raised by strict parsers when an option is repeated in an input source.

 Current implementation raises this exception only when an option is found
 more than once in a single file, string or dictionary.
 """

 def __init__(self, section, option, source=None, lineno=None):
 msg = [repr(option), " in section ", repr(section),
 " already exists"]
 if source is not None:
 message = ["While reading from ", repr(source)]
 if lineno is not None:
 message.append(" [line {0:2d}]".format(lineno))
 message.append(": option ")
 message.extend(msg)
 msg = message
 else:
 msg.insert(0, "Option ")
 Error.__init__(self, "".join(msg))
 self.section = section
 self.option = option
 self.source = source
 self.lineno = lineno
 self.args = (section, option, source, lineno)


class NoOptionError(Error):
 """A requested option was not found."""

 def __init__(self, option, section):
 Error.__init__(self, "No option %r in section: %r" %
 (option, section))
 self.option = option
 self.section = section
 self.args = (option, section)


class InterpolationError(Error):
 """Base class for interpolation-related exceptions."""

 def __init__(self, option, section, msg):
 Error.__init__(self, msg)
 self.option = option
 self.section = section
 self.args = (option, section, msg)


class InterpolationMissingOptionError(InterpolationError):
 """A string substitution required a setting which was not available."""

 def __init__(self, option, section, rawval, reference):
 msg = ("Bad value substitution: option {!r} in section {!r} contains "
 "an interpolation key {!r} which is not a valid option name. "
 "Raw value: {!r}".format(option, section, reference, rawval))
 InterpolationError.__init__(self, option, section, msg)
 self.reference = reference
 self.args = (option, section, rawval, reference)


class InterpolationSyntaxError(InterpolationError):
 """Raised when the source text contains invalid syntax.

 Current implementation raises this exception when the source text into
 which substitutions are made does not conform to the required syntax.
 """


class InterpolationDepthError(InterpolationError):
 """Raised when substitutions are nested too deeply."""

 def __init__(self, option, section, rawval):
 msg = ("Recursion limit exceeded in value substitution: option {!r} "
 "in section {!r} contains an interpolation key which "
 "cannot be substituted in {} steps. Raw value: {!r}"
 "".format(option, section, MAX_INTERPOLATION_DEPTH,
 rawval))
 InterpolationError.__init__(self, option, section, msg)
 self.args = (option, section, rawval)


class ParsingError(Error):
 """Raised when a configuration file does not follow legal syntax."""

 def __init__(self, source=None, filename=None):
 # Exactly one of `source'/`filename' arguments has to be given.
 # `filename' kept for compatibility.
 if filename and source:
 raise ValueError("Cannot specify both `filename' and `source'. "
 "Use `source'.")
 elif not filename and not source:
 raise ValueError("Required argument `source' not given.")
 elif filename:
 source = filename
 Error.__init__(self, 'Source contains parsing errors: %r' % source)
 self.source = source
 self.errors = []
 self.args = (source, )

 @property
 def filename(self):
 """Deprecated, use `source'."""
 warnings.warn(
 "The 'filename' attribute will be removed in future versions. "
 "Use 'source' instead.",
 DeprecationWarning, stacklevel=2
 )
 return self.source

 @filename.setter
 def filename(self, value):
 """Deprecated, user `source'."""
 warnings.warn(
 "The 'filename' attribute will be removed in future versions. "
 "Use 'source' instead.",
 DeprecationWarning, stacklevel=2
 )
 self.source = value

 def append(self, lineno, line):
 self.errors.append((lineno, line))
 self.message += '\n\t[line %2d]: %s' % (lineno, line)


class MissingSectionHeaderError(ParsingError):
 """Raised when a key-value pair is found before any section header."""

 def __init__(self, filename, lineno, line):
 Error.__init__(
 self,
 'File contains no section headers.\nfile: %r, line: %d\n%r' %
 (filename, lineno, line))
 self.source = filename
 self.lineno = lineno
 self.line = line
 self.args = (filename, lineno, line)


# Used in parser getters to indicate the default behaviour when a specific
# option is not found it to raise an exception. Created to enable `None' as
# a valid fallback value.
_UNSET = object()


class Interpolation:
 """Dummy interpolation that passes the value through with no changes."""

 def before_get(self, parser, section, option, value, defaults):
 return value

 def before_set(self, parser, section, option, value):
 return value

 def before_read(self, parser, section, option, value):
 return value

 def before_write(self, parser, section, option, value):
 return value


class BasicInterpolation(Interpolation):
 """Interpolation as implemented in the classic ConfigParser.

 The option values can contain format strings which refer to other values in
 the same section, or values in the special default section.

 For example:

 something: %(dir)s/whatever

 would resolve the "%(dir)s" to the value of dir. All reference
 expansions are done late, on demand. If a user needs to use a bare % in
 a configuration file, she can escape it by writing %%. Other % usage
 is considered a user error and raises `InterpolationSyntaxError'."""

 _KEYCRE = re.compile(r"%\(([^)]+)\)s")

 def before_get(self, parser, section, option, value, defaults):
 L = []
 self._interpolate_some(parser, option, L, value, section, defaults, 1)
 return ''.join(L)

 def before_set(self, parser, section, option, value):
 tmp_value = value.replace('%%', '') # escaped percent signs
 tmp_value = self._KEYCRE.sub('', tmp_value) # valid syntax
 if '%' in tmp_value:
 raise ValueError("invalid interpolation syntax in %r at "
 "position %d" % (value, tmp_value.find('%')))
 return value

 def _interpolate_some(self, parser, option, accum, rest, section, map,
 depth):
 rawval = parser.get(section, option, raw=True, fallback=rest)
 if depth > MAX_INTERPOLATION_DEPTH:
 raise InterpolationDepthError(option, section, rawval)
 while rest:
 p = rest.find("%")
 if p < 0:
 accum.append(rest)
 return
 if p > 0:
 accum.append(rest[:p])
 rest = rest[p:]
 # p is no longer used
 c = rest[1:2]
 if c == "%":
 accum.append("%")
 rest = rest[2:]
 elif c == "(":
 m = self._KEYCRE.match(rest)
 if m is None:
 raise InterpolationSyntaxError(option, section,
 "bad interpolation variable reference %r" % rest)
 var = parser.optionxform(m.group(1))
 rest = rest[m.end():]
 try:
 v = map[var]
 except KeyError:
 raise InterpolationMissingOptionError(
 option, section, rawval, var) from None
 if "%" in v:
 self._interpolate_some(parser, option, accum, v,
 section, map, depth + 1)
 else:
 accum.append(v)
 else:
 raise InterpolationSyntaxError(
 option, section,
 "'%%' must be followed by '%%' or '(', "
 "found: %r" % (rest,))


class ExtendedInterpolation(Interpolation):
 """Advanced variant of interpolation, supports the syntax used by
 `zc.buildout'. Enables interpolation between sections."""

 _KEYCRE = re.compile(r"\$\{([^}]+)\}")

 def before_get(self, parser, section, option, value, defaults):
 L = []
 self._interpolate_some(parser, option, L, value, section, defaults, 1)
 return ''.join(L)

 def before_set(self, parser, section, option, value):
 tmp_value = value.replace('$$', '') # escaped dollar signs
 tmp_value = self._KEYCRE.sub('', tmp_value) # valid syntax
 if '$' in tmp_value:
 raise ValueError("invalid interpolation syntax in %r at "
 "position %d" % (value, tmp_value.find('$')))
 return value

 def _interpolate_some(self, parser, option, accum, rest, section, map,
 depth):
 rawval = parser.get(section, option, raw=True, fallback=rest)
 if depth > MAX_INTERPOLATION_DEPTH:
 raise InterpolationDepthError(option, section, rawval)
 while rest:
 p = rest.find("$")
 if p < 0:
 accum.append(rest)
 return
 if p > 0:
 accum.append(rest[:p])
 rest = rest[p:]
 # p is no longer used
 c = rest[1:2]
 if c == "$":
 accum.append("$")
 rest = rest[2:]
 elif c == "{":
 m = self._KEYCRE.match(rest)
 if m is None:
 raise InterpolationSyntaxError(option, section,
 "bad interpolation variable reference %r" % rest)
 path = m.group(1).split(':')
 rest = rest[m.end():]
 sect = section
 opt = option
 try:
 if len(path) == 1:
 opt = parser.optionxform(path[0])
 v = map[opt]
 elif len(path) == 2:
 sect = path[0]
 opt = parser.optionxform(path[1])
 v = parser.get(sect, opt, raw=True)
 else:
 raise InterpolationSyntaxError(
 option, section,
 "More than one ':' found: %r" % (rest,))
 except (KeyError, NoSectionError, NoOptionError):
 raise InterpolationMissingOptionError(
 option, section, rawval, ":".join(path)) from None
 if "$" in v:
 self._interpolate_some(parser, opt, accum, v, sect,
 dict(parser.items(sect, raw=True)),
 depth + 1)
 else:
 accum.append(v)
 else:
 raise InterpolationSyntaxError(
 option, section,
 "'$' must be followed by '$' or '{', "
 "found: %r" % (rest,))


class LegacyInterpolation(Interpolation):
 """Deprecated interpolation used in old versions of ConfigParser.
 Use BasicInterpolation or ExtendedInterpolation instead."""

 _KEYCRE = re.compile(r"%\(([^)]*)\)s|.")

 def before_get(self, parser, section, option, value, vars):
 rawval = value
 depth = MAX_INTERPOLATION_DEPTH
 while depth: # Loop through this until it's done
 depth -= 1
 if value and "%(" in value:
 replace = functools.partial(self._interpolation_replace,
 parser=parser)
 value = self._KEYCRE.sub(replace, value)
 try:
 value = value % vars
 except KeyError as e:
 raise InterpolationMissingOptionError(
 option, section, rawval, e.args[0]) from None
 else:
 break
 if value and "%(" in value:
 raise InterpolationDepthError(option, section, rawval)
 return value

 def before_set(self, parser, section, option, value):
 return value

 @staticmethod
 def _interpolation_replace(match, parser):
 s = match.group(1)
 if s is None:
 return match.group()
 else:
 return "%%(%s)s" % parser.optionxform(s)


class RawConfigParser(MutableMapping):
 """ConfigParser that does not do interpolation."""

 # Regular expressions for parsing section headers and options
 _SECT_TMPL = r"""
 \[ # [
 (?P<header>[^]]+) # very permissive!
 \] # ]
 """
 _OPT_TMPL = r"""
 (?P<option>.*?) # very permissive!
 \s*(?P<vi>{delim})\s* # any number of space/tab,
 # followed by any of the
 # allowed delimiters,
 # followed by any space/tab
 (?P<value>.*)$ # everything up to eol
 """
 _OPT_NV_TMPL = r"""
 (?P<option>.*?) # very permissive!
 \s*(?: # any number of space/tab,
 (?P<vi>{delim})\s* # optionally followed by
 # any of the allowed
 # delimiters, followed by any
 # space/tab
 (?P<value>.*))?$ # everything up to eol
 """
 # Interpolation algorithm to be used if the user does not specify another
 _DEFAULT_INTERPOLATION = Interpolation()
 # Compiled regular expression for matching sections
 SECTCRE = re.compile(_SECT_TMPL, re.VERBOSE)
 # Compiled regular expression for matching options with typical separators
 OPTCRE = re.compile(_OPT_TMPL.format(delim="=|:"), re.VERBOSE)
 # Compiled regular expression for matching options with optional values
 # delimited using typical separators
 OPTCRE_NV = re.compile(_OPT_NV_TMPL.format(delim="=|:"), re.VERBOSE)
 # Compiled regular expression for matching leading whitespace in a line
 NONSPACECRE = re.compile(r"\S")
 # Possible boolean values in the configuration.
 BOOLEAN_STATES = {'1': True, 'yes': True, 'true': True, 'on': True,
 '0': False, 'no': False, 'false': False, 'off': False}

 def __init__(self, defaults=None, dict_type=_default_dict,
 allow_no_value=False, *, delimiters=('=', ':'),
 comment_prefixes=('#', ';'), inline_comment_prefixes=None,
 strict=True, empty_lines_in_values=True,
 default_section=DEFAULTSECT,
 interpolation=_UNSET, converters=_UNSET):

 self._dict = dict_type
 self._sections = self._dict()
 self._defaults = self._dict()
 self._converters = ConverterMapping(self)
 self._proxies = self._dict()
 self._proxies[default_section] = SectionProxy(self, default_section)
 self._delimiters = tuple(delimiters)
 if delimiters == ('=', ':'):
 self._optcre = self.OPTCRE_NV if allow_no_value else self.OPTCRE
 else:
 d = "|".join(re.escape(d) for d in delimiters)
 if allow_no_value:
 self._optcre = re.compile(self._OPT_NV_TMPL.format(delim=d),
 re.VERBOSE)
 else:
 self._optcre = re.compile(self._OPT_TMPL.format(delim=d),
 re.VERBOSE)
 self._comment_prefixes = tuple(comment_prefixes or ())
 self._inline_comment_prefixes = tuple(inline_comment_prefixes or ())
 self._strict = strict
 self._allow_no_value = allow_no_value
 self._empty_lines_in_values = empty_lines_in_values
 self.default_section=default_section
 self._interpolation = interpolation
 if self._interpolation is _UNSET:
 self._interpolation = self._DEFAULT_INTERPOLATION
 if self._interpolation is None:
 self._interpolation = Interpolation()
 if converters is not _UNSET:
 self._converters.update(converters)
 if defaults:
 self._read_defaults(defaults)

 def defaults(self):
 return self._defaults

 def sections(self):
 """Return a list of section names, excluding [DEFAULT]"""
 # self._sections will never have [DEFAULT] in it
 return list(self._sections.keys())

 def add_section(self, section):
 """Create a new section in the configuration.

 Raise DuplicateSectionError if a section by the specified name
 already exists. Raise ValueError if name is DEFAULT.
 """
 if section == self.default_section:
 raise ValueError('Invalid section name: %r' % section)

 if section in self._sections:
 raise DuplicateSectionError(section)
 self._sections[section] = self._dict()
 self._proxies[section] = SectionProxy(self, section)

 def has_section(self, section):
 """Indicate whether the named section is present in the configuration.

 The DEFAULT section is not acknowledged.
 """
 return section in self._sections

 def options(self, section):
 """Return a list of option names for the given section name."""
 try:
 opts = self._sections[section].copy()
 except KeyError:
 raise NoSectionError(section) from None
 opts.update(self._defaults)
 return list(opts.keys())

 def read(self, filenames, encoding=None):
 """Read and parse a filename or an iterable of filenames.

 Files that cannot be opened are silently ignored; this is
 designed so that you can specify an iterable of potential
 configuration file locations (e.g. current directory, user's
 home directory, systemwide directory), and all existing
 configuration files in the iterable will be read. A single
 filename may also be given.

 Return list of successfully read files.
 """
 if isinstance(filenames, (str, bytes, os.PathLike)):
 filenames = [filenames]
 read_ok = []
 for filename in filenames:
 try:
 with open(filename, encoding=encoding) as fp:
 self._read(fp, filename)
 except OSError:
 continue
 if isinstance(filename, os.PathLike):
 filename = os.fspath(filename)
 read_ok.append(filename)
 return read_ok

 def read_file(self, f, source=None):
 """Like read() but the argument must be a file-like object.

 The `f' argument must be iterable, returning one line at a time.
 Optional second argument is the `source' specifying the name of the
 file being read. If not given, it is taken from f.name. If `f' has no
 `name' attribute, `<???>' is used.
 """
 if source is None:
 try:
 source = f.name
 except AttributeError:
 source = '<???>'
 self._read(f, source)

 def read_string(self, string, source='<string>'):
 """Read configuration from a given string."""
 sfile = io.StringIO(string)
 self.read_file(sfile, source)

 def read_dict(self, dictionary, source='<dict>'):
 """Read configuration from a dictionary.

 Keys are section names, values are dictionaries with keys and values
 that should be present in the section. If the used dictionary type
 preserves order, sections and their keys will be added in order.

 All types held in the dictionary are converted to strings during
 reading, including section names, option names and keys.

 Optional second argument is the `source' specifying the name of the
 dictionary being read.
 """
 elements_added = set()
 for section, keys in dictionary.items():
 section = str(section)
 try:
 self.add_section(section)
 except (DuplicateSectionError, ValueError):
 if self._strict and section in elements_added:
 raise
 elements_added.add(section)
 for key, value in keys.items():
 key = self.optionxform(str(key))
 if value is not None:
 value = str(value)
 if self._strict and (section, key) in elements_added:
 raise DuplicateOptionError(section, key, source)
 elements_added.add((section, key))
 self.set(section, key, value)

 def readfp(self, fp, filename=None):
 """Deprecated, use read_file instead."""
 warnings.warn(
 "This method will be removed in future versions. "
 "Use 'parser.read_file()' instead.",
 DeprecationWarning, stacklevel=2
 )
 self.read_file(fp, source=filename)

 def get(self, section, option, *, raw=False, vars=None, fallback=_UNSET):
 """Get an option value for a given section.

 If `vars' is provided, it must be a dictionary. The option is looked up
 in `vars' (if provided), `section', and in `DEFAULTSECT' in that order.
 If the key is not found and `fallback' is provided, it is used as
 a fallback value. `None' can be provided as a `fallback' value.

 If interpolation is enabled and the optional argument `raw' is False,
 all interpolations are expanded in the return values.

 Arguments `raw', `vars', and `fallback' are keyword only.

 The section DEFAULT is special.
 """
 try:
 d = self._unify_values(section, vars)
 except NoSectionError:
 if fallback is _UNSET:
 raise
 else:
 return fallback
 option = self.optionxform(option)
 try:
 value = d[option]
 except KeyError:
 if fallback is _UNSET:
 raise NoOptionError(option, section)
 else:
 return fallback

 if raw or value is None:
 return value
 else:
 return self._interpolation.before_get(self, section, option, value,
 d)

 def _get(self, section, conv, option, **kwargs):
 return conv(self.get(section, option, **kwargs))

 def _get_conv(self, section, option, conv, *, raw=False, vars=None,
 fallback=_UNSET, **kwargs):
 try:
 return self._get(section, conv, option, raw=raw, vars=vars,
 **kwargs)
 except (NoSectionError, NoOptionError):
 if fallback is _UNSET:
 raise
 return fallback

 # getint, getfloat and getboolean provided directly for backwards compat
 def getint(self, section, option, *, raw=False, vars=None,
 fallback=_UNSET, **kwargs):
 return self._get_conv(section, option, int, raw=raw, vars=vars,
 fallback=fallback, **kwargs)

 def getfloat(self, section, option, *, raw=False, vars=None,
 fallback=_UNSET, **kwargs):
 return self._get_conv(section, option, float, raw=raw, vars=vars,
 fallback=fallback, **kwargs)

 def getboolean(self, section, option, *, raw=False, vars=None,
 fallback=_UNSET, **kwargs):
 return self._get_conv(section, option, self._convert_to_boolean,
 raw=raw, vars=vars, fallback=fallback, **kwargs)

 def items(self, section=_UNSET, raw=False, vars=None):
 """Return a list of (name, value) tuples for each option in a section.

 All % interpolations are expanded in the return values, based on the
 defaults passed into the constructor, unless the optional argument
 `raw' is true. Additional substitutions may be provided using the
 `vars' argument, which must be a dictionary whose contents overrides
 any pre-existing defaults.

 The section DEFAULT is special.
 """
 if section is _UNSET:
 return super().items()
 d = self._defaults.copy()
 try:
 d.update(self._sections[section])
 except KeyError:
 if section != self.default_section:
 raise NoSectionError(section)
 orig_keys = list(d.keys())
 # Update with the entry specific variables
 if vars:
 for key, value in vars.items():
 d[self.optionxform(key)] = value
 value_getter = lambda option: self._interpolation.before_get(self,
 section, option, d[option], d)
 if raw:
 value_getter = lambda option: d[option]
 return [(option, value_getter(option)) for option in orig_keys]

 def popitem(self):
 """Remove a section from the parser and return it as
 a (section_name, section_proxy) tuple. If no section is present, raise
 KeyError.

 The section DEFAULT is never returned because it cannot be removed.
 """
 for key in self.sections():
 value = self[key]
 del self[key]
 return key, value
 raise KeyError

 def optionxform(self, optionstr):
 return optionstr.lower()

 def has_option(self, section, option):
 """Check for the existence of a given option in a given section.
 If the specified `section' is None or an empty string, DEFAULT is
 assumed. If the specified `section' does not exist, returns False."""
 if not section or section == self.default_section:
 option = self.optionxform(option)
 return option in self._defaults
 elif section not in self._sections:
 return False
 else:
 option = self.optionxform(option)
 return (option in self._sections[section]
 or option in self._defaults)

 def set(self, section, option, value=None):
 """Set an option."""
 if value:
 value = self._interpolation.before_set(self, section, option,
 value)
 if not section or section == self.default_section:
 sectdict = self._defaults
 else:
 try:
 sectdict = self._sections[section]
 except KeyError:
 raise NoSectionError(section) from None
 sectdict[self.optionxform(option)] = value

 def write(self, fp, space_around_delimiters=True):
 """Write an .ini-format representation of the configuration state.

 If `space_around_delimiters' is True (the default), delimiters
 between keys and values are surrounded by spaces.
 """
 if space_around_delimiters:
 d = " {} ".format(self._delimiters[0])
 else:
 d = self._delimiters[0]
 if self._defaults:
 self._write_section(fp, self.default_section,
 self._defaults.items(), d)
 for section in self._sections:
 self._write_section(fp, section,
 self._sections[section].items(), d)

 def _write_section(self, fp, section_name, section_items, delimiter):
 """Write a single section to the specified `fp'."""
 fp.write("[{}]\n".format(section_name))
 for key, value in section_items:
 value = self._interpolation.before_write(self, section_name, key,
 value)
 if value is not None or not self._allow_no_value:
 value = delimiter + str(value).replace('\n', '\n\t')
 else:
 value = ""
 fp.write("{}{}\n".format(key, value))
 fp.write("\n")

 def remove_option(self, section, option):
 """Remove an option."""
 if not section or section == self.default_section:
 sectdict = self._defaults
 else:
 try:
 sectdict = self._sections[section]
 except KeyError:
 raise NoSectionError(section) from None
 option = self.optionxform(option)
 existed = option in sectdict
 if existed:
 del sectdict[option]
 return existed

 def remove_section(self, section):
 """Remove a file section."""
 existed = section in self._sections
 if existed:
 del self._sections[section]
 del self._proxies[section]
 return existed

 def __getitem__(self, key):
 if key != self.default_section and not self.has_section(key):
 raise KeyError(key)
 return self._proxies[key]

 def __setitem__(self, key, value):
 # To conform with the mapping protocol, overwrites existing values in
 # the section.
 if key in self and self[key] is value:
 return
 # XXX this is not atomic if read_dict fails at any point. Then again,
 # no update method in configparser is atomic in this implementation.
 if key == self.default_section:
 self._defaults.clear()
 elif key in self._sections:
 self._sections[key].clear()
 self.read_dict({key: value})

 def __delitem__(self, key):
 if key == self.default_section:
 raise ValueError("Cannot remove the default section.")
 if not self.has_section(key):
 raise KeyError(key)
 self.remove_section(key)

 def __contains__(self, key):
 return key == self.default_section or self.has_section(key)

 def __len__(self):
 return len(self._sections) + 1 # the default section

 def __iter__(self):
 # XXX does it break when underlying container state changed?
 return itertools.chain((self.default_section,), self._sections.keys())

 def _read(self, fp, fpname):
 """Parse a sectioned configuration file.

 Each section in a configuration file contains a header, indicated by
 a name in square brackets (`[]'), plus key/value options, indicated by
 `name' and `value' delimited with a specific substring (`=' or `:' by
 default).

 Values can span multiple lines, as long as they are indented deeper
 than the first line of the value. Depending on the parser's mode, blank
 lines may be treated as parts of multiline values or ignored.

 Configuration files may include comments, prefixed by specific
 characters (`#' and `;' by default). Comments may appear on their own
 in an otherwise empty line or may be entered in lines holding values or
 section names.
 """
 elements_added = set()
 cursect = None # None, or a dictionary
 sectname = None
 optname = None
 lineno = 0
 indent_level = 0
 e = None # None, or an exception
 for lineno, line in enumerate(fp, start=1):
 comment_start = sys.maxsize
 # strip inline comments
 inline_prefixes = {p: -1 for p in self._inline_comment_prefixes}
 while comment_start == sys.maxsize and inline_prefixes:
 next_prefixes = {}
 for prefix, index in inline_prefixes.items():
 index = line.find(prefix, index+1)
 if index == -1:
 continue
 next_prefixes[prefix] = index
 if index == 0 or (index > 0 and line[index-1].isspace()):
 comment_start = min(comment_start, index)
 inline_prefixes = next_prefixes
 # strip full line comments
 for prefix in self._comment_prefixes:
 if line.strip().startswith(prefix):
 comment_start = 0
 break
 if comment_start == sys.maxsize:
 comment_start = None
 value = line[:comment_start].strip()
 if not value:
 if self._empty_lines_in_values:
 # add empty line to the value, but only if there was no
 # comment on the line
 if (comment_start is None and
 cursect is not None and
 optname and
 cursect[optname] is not None):
 cursect[optname].append('') # newlines added at join
 else:
 # empty line marks end of value
 indent_level = sys.maxsize
 continue
 # continuation line?
 first_nonspace = self.NONSPACECRE.search(line)
 cur_indent_level = first_nonspace.start() if first_nonspace else 0
 if (cursect is not None and optname and
 cur_indent_level > indent_level):
 cursect[optname].append(value)
 # a section header or option header?
 else:
 indent_level = cur_indent_level
 # is it a section header?
 mo = self.SECTCRE.match(value)
 if mo:
 sectname = mo.group('header')
 if sectname in self._sections:
 if self._strict and sectname in elements_added:
 raise DuplicateSectionError(sectname, fpname,
 lineno)
 cursect = self._sections[sectname]
 elements_added.add(sectname)
 elif sectname == self.default_section:
 cursect = self._defaults
 else:
 cursect = self._dict()
 self._sections[sectname] = cursect
 self._proxies[sectname] = SectionProxy(self, sectname)
 elements_added.add(sectname)
 # So sections can't start with a continuation line
 optname = None
 # no section header in the file?
 elif cursect is None:
 raise MissingSectionHeaderError(fpname, lineno, line)
 # an option line?
 else:
 mo = self._optcre.match(value)
 if mo:
 optname, vi, optval = mo.group('option', 'vi', 'value')
 if not optname:
 e = self._handle_error(e, fpname, lineno, line)
 optname = self.optionxform(optname.rstrip())
 if (self._strict and
 (sectname, optname) in elements_added):
 raise DuplicateOptionError(sectname, optname,
 fpname, lineno)
 elements_added.add((sectname, optname))
 # This check is fine because the OPTCRE cannot
 # match if it would set optval to None
 if optval is not None:
 optval = optval.strip()
 cursect[optname] = [optval]
 else:
 # valueless option handling
 cursect[optname] = None
 else:
 # a non-fatal parsing error occurred. set up the
 # exception but keep going. the exception will be
 # raised at the end of the file and will contain a
 # list of all bogus lines
 e = self._handle_error(e, fpname, lineno, line)
 self._join_multiline_values()
 # if any parsing errors occurred, raise an exception
 if e:
 raise e

 def _join_multiline_values(self):
 defaults = self.default_section, self._defaults
 all_sections = itertools.chain((defaults,),
 self._sections.items())
 for section, options in all_sections:
 for name, val in options.items():
 if isinstance(val, list):
 val = '\n'.join(val).rstrip()
 options[name] = self._interpolation.before_read(self,
 section,
 name, val)

 def _read_defaults(self, defaults):
 """Read the defaults passed in the initializer.
 Note: values can be non-string."""
 for key, value in defaults.items():
 self._defaults[self.optionxform(key)] = value

 def _handle_error(self, exc, fpname, lineno, line):
 if not exc:
 exc = ParsingError(fpname)
 exc.append(lineno, repr(line))
 return exc

 def _unify_values(self, section, vars):
 """Create a sequence of lookups with 'vars' taking priority over
 the 'section' which takes priority over the DEFAULTSECT.

 """
 sectiondict = {}
 try:
 sectiondict = self._sections[section]
 except KeyError:
 if section != self.default_section:
 raise NoSectionError(section) from None
 # Update with the entry specific variables
 vardict = {}
 if vars:
 for key, value in vars.items():
 if value is not None:
 value = str(value)
 vardict[self.optionxform(key)] = value
 return _ChainMap(vardict, sectiondict, self._defaults)

 def _convert_to_boolean(self, value):
 """Return a boolean value translating from other types if necessary.
 """
 if value.lower() not in self.BOOLEAN_STATES:
 raise ValueError('Not a boolean: %s' % value)
 return self.BOOLEAN_STATES[value.lower()]

 def _validate_value_types(self, *, section="", option="", value=""):
 """Raises a TypeError for non-string values.

 The only legal non-string value if we allow valueless
 options is None, so we need to check if the value is a
 string if:
 - we do not allow valueless options, or
 - we allow valueless options but the value is not None

 For compatibility reasons this method is not used in classic set()
 for RawConfigParsers. It is invoked in every case for mapping protocol
 access and in ConfigParser.set().
 """
 if not isinstance(section, str):
 raise TypeError("section names must be strings")
 if not isinstance(option, str):
 raise TypeError("option keys must be strings")
 if not self._allow_no_value or value:
 if not isinstance(value, str):
 raise TypeError("option values must be strings")

 @property
 def converters(self):
 return self._converters


class ConfigParser(RawConfigParser):
 """ConfigParser implementing interpolation."""

 _DEFAULT_INTERPOLATION = BasicInterpolation()

 def set(self, section, option, value=None):
 """Set an option. Extends RawConfigParser.set by validating type and
 interpolation syntax on the value."""
 self._validate_value_types(option=option, value=value)
 super().set(section, option, value)

 def add_section(self, section):
 """Create a new section in the configuration. Extends
 RawConfigParser.add_section by validating if the section name is
 a string."""
 self._validate_value_types(section=section)
 super().add_section(section)

 def _read_defaults(self, defaults):
 """Reads the defaults passed in the initializer, implicitly converting
 values to strings like the rest of the API.

 Does not perform interpolation for backwards compatibility.
 """
 try:
 hold_interpolation = self._interpolation
 self._interpolation = Interpolation()
 self.read_dict({self.default_section: defaults})
 finally:
 self._interpolation = hold_interpolation


class SafeConfigParser(ConfigParser):
 """ConfigParser alias for backwards compatibility purposes."""

 def __init__(self, *args, **kwargs):
 super().__init__(*args, **kwargs)
 warnings.warn(
 "The SafeConfigParser class has been renamed to ConfigParser "
 "in Python 3.2. This alias will be removed in future versions."
 " Use ConfigParser directly instead.",
 DeprecationWarning, stacklevel=2
 )


class SectionProxy(MutableMapping):
 """A proxy for a single section from a parser."""

 def __init__(self, parser, name):
 """Creates a view on a section of the specified `name` in `parser`."""
 self._parser = parser
 self._name = name
 for conv in parser.converters:
 key = 'get' + conv
 getter = functools.partial(self.get, _impl=getattr(parser, key))
 setattr(self, key, getter)

 def __repr__(self):
 return '<Section: {}>'.format(self._name)

 def __getitem__(self, key):
 if not self._parser.has_option(self._name, key):
 raise KeyError(key)
 return self._parser.get(self._name, key)

 def __setitem__(self, key, value):
 self._parser._validate_value_types(option=key, value=value)
 return self._parser.set(self._name, key, value)

 def __delitem__(self, key):
 if not (self._parser.has_option(self._name, key) and
 self._parser.remove_option(self._name, key)):
 raise KeyError(key)

 def __contains__(self, key):
 return self._parser.has_option(self._name, key)

 def __len__(self):
 return len(self._options())

 def __iter__(self):
 return self._options().__iter__()

 def _options(self):
 if self._name != self._parser.default_section:
 return self._parser.options(self._name)
 else:
 return self._parser.defaults()

 @property
 def parser(self):
 # The parser object of the proxy is read-only.
 return self._parser

 @property
 def name(self):
 # The name of the section on a proxy is read-only.
 return self._name

 def get(self, option, fallback=None, *, raw=False, vars=None,
 _impl=None, **kwargs):
 """Get an option value.

 Unless `fallback` is provided, `None` will be returned if the option
 is not found.

 """
 # If `_impl` is provided, it should be a getter method on the parser
 # object that provides the desired type conversion.
 if not _impl:
 _impl = self._parser.get
 return _impl(self._name, option, raw=raw, vars=vars,
 fallback=fallback, **kwargs)


class ConverterMapping(MutableMapping):
 """Enables reuse of get*() methods between the parser and section proxies.

 If a parser class implements a getter directly, the value for the given
 key will be ``None``. The presence of the converter name here enables
 section proxies to find and use the implementation on the parser class.
 """

 GETTERCRE = re.compile(r"^get(?P<name>.+)$")

 def __init__(self, parser):
 self._parser = parser
 self._data = {}
 for getter in dir(self._parser):
 m = self.GETTERCRE.match(getter)
 if not m or not callable(getattr(self._parser, getter)):
 continue
 self._data[m.group('name')] = None # See class docstring.

 def __getitem__(self, key):
 return self._data[key]

 def __setitem__(self, key, value):
 try:
 k = 'get' + key
 except TypeError:
 raise ValueError('Incompatible key: {} (type: {})'
 ''.format(key, type(key)))
 if k == 'get':
 raise ValueError('Incompatible key: cannot use "" as a name')
 self._data[key] = value
 func = functools.partial(self._parser._get_conv, conv=value)
 func.converter = value
 setattr(self._parser, k, func)
 for proxy in self._parser.values():
 getter = functools.partial(proxy.get, _impl=func)
 setattr(proxy, k, getter)

 def __delitem__(self, key):
 try:
 k = 'get' + (key or None)
 except TypeError:
 raise KeyError(key)
 del self._data[key]
 for inst in itertools.chain((self._parser,), self._parser.values()):
 try:
 delattr(inst, k)
 except AttributeError:
 # don't raise since the entry was present in _data, silently
 # clean up
 continue

 def __iter__(self):
 return iter(self._data)

 def __len__(self):
 return len(self._data)