configitems: register the 'web.push_ssl' config

mercurial/configitems.py

@@ -1,770 +1,773 b''
 # configitems.py - centralized declaration of configuration option
 #
 #  Copyright 2017 Pierre-Yves David <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
 
 import functools
 
 from . import (
     encoding,
     error,
 )
 
 def loadconfigtable(ui, extname, configtable):
     """update config item known to the ui with the extension ones"""
     for section, items in configtable.items():
         knownitems = ui._knownconfig.setdefault(section, {})
         knownkeys = set(knownitems)
         newkeys = set(items)
         for key in sorted(knownkeys & newkeys):
             msg = "extension '%s' overwrite config item '%s.%s'"
             msg %= (extname, section, key)
             ui.develwarn(msg, config='warn-config')
 
         knownitems.update(items)
 
 class configitem(object):
     """represent a known config item
 
     :section: the official config section where to find this item,
        :name: the official name within the section,
     :default: default value for this item,
     :alias: optional list of tuples as alternatives.
     """
 
     def __init__(self, section, name, default=None, alias=()):
         self.section = section
         self.name = name
         self.default = default
         self.alias = list(alias)
 
 coreitems = {}
 
 def _register(configtable, *args, **kwargs):
     item = configitem(*args, **kwargs)
     section = configtable.setdefault(item.section, {})
     if item.name in section:
         msg = "duplicated config item registration for '%s.%s'"
         raise error.ProgrammingError(msg % (item.section, item.name))
     section[item.name] = item
 
 # special value for case where the default is derived from other values
 dynamicdefault = object()
 
 # Registering actual config items
 
 def getitemregister(configtable):
     return functools.partial(_register, configtable)
 
 coreconfigitem = getitemregister(coreitems)
 
 coreconfigitem('auth', 'cookiefile',
     default=None,
 )
 # bookmarks.pushing: internal hack for discovery
 coreconfigitem('bookmarks', 'pushing',
     default=list,
 )
 # bundle.mainreporoot: internal hack for bundlerepo
 coreconfigitem('bundle', 'mainreporoot',
     default='',
 )
 # bundle.reorder: experimental config
 coreconfigitem('bundle', 'reorder',
     default='auto',
 )
 coreconfigitem('censor', 'policy',
     default='abort',
 )
 coreconfigitem('chgserver', 'idletimeout',
     default=3600,
 )
 coreconfigitem('chgserver', 'skiphash',
     default=False,
 )
 coreconfigitem('cmdserver', 'log',
     default=None,
 )
 coreconfigitem('color', 'mode',
     default='auto',
 )
 coreconfigitem('color', 'pagermode',
     default=dynamicdefault,
 )
 coreconfigitem('commands', 'status.relative',
     default=False,
 )
 coreconfigitem('commands', 'status.skipstates',
     default=[],
 )
 coreconfigitem('commands', 'status.verbose',
     default=False,
 )
 coreconfigitem('commands', 'update.requiredest',
     default=False,
 )
 coreconfigitem('debug', 'dirstate.delaywrite',
     default=0,
 )
 coreconfigitem('devel', 'all-warnings',
     default=False,
 )
 coreconfigitem('devel', 'bundle2.debug',
     default=False,
 )
 coreconfigitem('devel', 'cache-vfs',
     default=None,
 )
 coreconfigitem('devel', 'check-locks',
     default=False,
 )
 coreconfigitem('devel', 'check-relroot',
     default=False,
 )
 coreconfigitem('devel', 'default-date',
     default=None,
 )
 coreconfigitem('devel', 'deprec-warn',
     default=False,
 )
 coreconfigitem('devel', 'disableloaddefaultcerts',
     default=False,
 )
 coreconfigitem('devel', 'empty-changegroup',
     default=False,
 )
 coreconfigitem('devel', 'legacy.exchange',
     default=list,
 )
 coreconfigitem('devel', 'servercafile',
     default='',
 )
 coreconfigitem('devel', 'serverexactprotocol',
     default='',
 )
 coreconfigitem('devel', 'serverrequirecert',
     default=False,
 )
 coreconfigitem('devel', 'strip-obsmarkers',
     default=True,
 )
 coreconfigitem('devel', 'warn-config',
     default=None,
 )
 coreconfigitem('devel', 'warn-config-default',
     default=None,
 )
 coreconfigitem('devel', 'user.obsmarker',
     default=None,
 )
 coreconfigitem('diff', 'nodates',
     default=None,
 )
 coreconfigitem('diff', 'showfunc',
     default=None,
 )
 coreconfigitem('diff', 'unified',
     default=None,
 )
 coreconfigitem('diff', 'git',
     default=None,
 )
 coreconfigitem('diff', 'ignorews',
     default=None,
 )
 coreconfigitem('diff', 'ignorewsamount',
     default=None,
 )
 coreconfigitem('diff', 'ignoreblanklines',
     default=None,
 )
 coreconfigitem('diff', 'ignorewseol',
     default=None,
 )
 coreconfigitem('diff', 'nobinary',
     default=None,
 )
 coreconfigitem('diff', 'noprefix',
     default=None,
 )
 coreconfigitem('email', 'charsets',
     default=list,
 )
 coreconfigitem('email', 'from',
     default=None,
 )
 coreconfigitem('email', 'method',
     default='smtp',
 )
 coreconfigitem('experimental', 'allowdivergence',
     default=False,
 )
 coreconfigitem('experimental', 'bundle-phases',
     default=False,
 )
 coreconfigitem('experimental', 'bundle2-advertise',
     default=True,
 )
 coreconfigitem('experimental', 'bundle2-output-capture',
     default=False,
 )
 coreconfigitem('experimental', 'bundle2.pushback',
     default=False,
 )
 coreconfigitem('experimental', 'bundle2lazylocking',
     default=False,
 )
 coreconfigitem('experimental', 'bundlecomplevel',
     default=None,
 )
 coreconfigitem('experimental', 'changegroup3',
     default=False,
 )
 coreconfigitem('experimental', 'clientcompressionengines',
     default=list,
 )
 coreconfigitem('experimental', 'copytrace',
     default='on',
 )
 coreconfigitem('experimental', 'copytrace.sourcecommitlimit',
     default=100,
 )
 coreconfigitem('experimental', 'crecordtest',
     default=None,
 )
 coreconfigitem('experimental', 'editortmpinhg',
     default=False,
 )
 coreconfigitem('experimental', 'maxdeltachainspan',
     default=-1,
 )
 coreconfigitem('experimental', 'mmapindexthreshold',
     default=None,
 )
 coreconfigitem('experimental', 'nonnormalparanoidcheck',
     default=False,
 )
 coreconfigitem('experimental', 'stabilization',
     default=list,
     alias=[('experimental', 'evolution')],
 )
 coreconfigitem('experimental', 'stabilization.bundle-obsmarker',
     default=False,
     alias=[('experimental', 'evolution.bundle-obsmarker')],
 )
 coreconfigitem('experimental', 'stabilization.track-operation',
     default=True,
     alias=[('experimental', 'evolution.track-operation')]
 )
 coreconfigitem('experimental', 'exportableenviron',
     default=list,
 )
 coreconfigitem('experimental', 'extendedheader.index',
     default=None,
 )
 coreconfigitem('experimental', 'extendedheader.similarity',
     default=False,
 )
 coreconfigitem('experimental', 'format.compression',
     default='zlib',
 )
 coreconfigitem('experimental', 'graphshorten',
     default=False,
 )
 coreconfigitem('experimental', 'graphstyle.parent',
     default=dynamicdefault,
 )
 coreconfigitem('experimental', 'graphstyle.missing',
     default=dynamicdefault,
 )
 coreconfigitem('experimental', 'graphstyle.grandparent',
     default=dynamicdefault,
 )
 coreconfigitem('experimental', 'hook-track-tags',
     default=False,
 )
 coreconfigitem('experimental', 'httppostargs',
     default=False,
 )
 coreconfigitem('experimental', 'manifestv2',
     default=False,
 )
 coreconfigitem('experimental', 'mergedriver',
     default=None,
 )
 coreconfigitem('experimental', 'obsmarkers-exchange-debug',
     default=False,
 )
 coreconfigitem('experimental', 'rebase.multidest',
     default=False,
 )
 coreconfigitem('experimental', 'revertalternateinteractivemode',
     default=True,
 )
 coreconfigitem('experimental', 'revlogv2',
     default=None,
 )
 coreconfigitem('experimental', 'spacemovesdown',
     default=False,
 )
 coreconfigitem('experimental', 'treemanifest',
     default=False,
 )
 coreconfigitem('experimental', 'updatecheck',
     default=None,
 )
 coreconfigitem('format', 'aggressivemergedeltas',
     default=False,
 )
 coreconfigitem('format', 'chunkcachesize',
     default=None,
 )
 coreconfigitem('format', 'dotencode',
     default=True,
 )
 coreconfigitem('format', 'generaldelta',
     default=False,
 )
 coreconfigitem('format', 'manifestcachesize',
     default=None,
 )
 coreconfigitem('format', 'maxchainlen',
     default=None,
 )
 coreconfigitem('format', 'obsstore-version',
     default=None,
 )
 coreconfigitem('format', 'usefncache',
     default=True,
 )
 coreconfigitem('format', 'usegeneraldelta',
     default=True,
 )
 coreconfigitem('format', 'usestore',
     default=True,
 )
 coreconfigitem('hostsecurity', 'ciphers',
     default=None,
 )
 coreconfigitem('hostsecurity', 'disabletls10warning',
     default=False,
 )
 coreconfigitem('http_proxy', 'always',
     default=False,
 )
 coreconfigitem('http_proxy', 'host',
     default=None,
 )
 coreconfigitem('http_proxy', 'no',
     default=list,
 )
 coreconfigitem('http_proxy', 'passwd',
     default=None,
 )
 coreconfigitem('http_proxy', 'user',
     default=None,
 )
 coreconfigitem('merge', 'checkunknown',
     default='abort',
 )
 coreconfigitem('merge', 'checkignored',
     default='abort',
 )
 coreconfigitem('merge', 'followcopies',
     default=True,
 )
 coreconfigitem('merge', 'preferancestor',
         default=lambda: ['*'],
 )
 coreconfigitem('pager', 'ignore',
     default=list,
 )
 coreconfigitem('patch', 'eol',
     default='strict',
 )
 coreconfigitem('patch', 'fuzz',
     default=2,
 )
 coreconfigitem('paths', 'default',
     default=None,
 )
 coreconfigitem('paths', 'default-push',
     default=None,
 )
 coreconfigitem('phases', 'checksubrepos',
     default='follow',
 )
 coreconfigitem('phases', 'new-commit',
     default='draft',
 )
 coreconfigitem('phases', 'publish',
     default=True,
 )
 coreconfigitem('profiling', 'enabled',
     default=False,
 )
 coreconfigitem('profiling', 'format',
     default='text',
 )
 coreconfigitem('profiling', 'freq',
     default=1000,
 )
 coreconfigitem('profiling', 'limit',
     default=30,
 )
 coreconfigitem('profiling', 'nested',
     default=0,
 )
 coreconfigitem('profiling', 'output',
     default=None,
 )
 coreconfigitem('profiling', 'showmax',
     default=0.999,
 )
 coreconfigitem('profiling', 'showmin',
     default=dynamicdefault,
 )
 coreconfigitem('profiling', 'sort',
     default='inlinetime',
 )
 coreconfigitem('profiling', 'statformat',
     default='hotpath',
 )
 coreconfigitem('profiling', 'type',
     default='stat',
 )
 coreconfigitem('progress', 'assume-tty',
     default=False,
 )
 coreconfigitem('progress', 'changedelay',
     default=1,
 )
 coreconfigitem('progress', 'clear-complete',
     default=True,
 )
 coreconfigitem('progress', 'debug',
     default=False,
 )
 coreconfigitem('progress', 'delay',
     default=3,
 )
 coreconfigitem('progress', 'disable',
     default=False,
 )
 coreconfigitem('progress', 'estimateinterval',
     default=60.0,
 )
 coreconfigitem('progress', 'refresh',
     default=0.1,
 )
 coreconfigitem('progress', 'width',
     default=dynamicdefault,
 )
 coreconfigitem('push', 'pushvars.server',
     default=False,
 )
 coreconfigitem('server', 'bundle1',
     default=True,
 )
 coreconfigitem('server', 'bundle1gd',
     default=None,
 )
 coreconfigitem('server', 'compressionengines',
     default=list,
 )
 coreconfigitem('server', 'concurrent-push-mode',
     default='strict',
 )
 coreconfigitem('server', 'disablefullbundle',
     default=False,
 )
 coreconfigitem('server', 'maxhttpheaderlen',
     default=1024,
 )
 coreconfigitem('server', 'preferuncompressed',
     default=False,
 )
 coreconfigitem('server', 'uncompressed',
     default=True,
 )
 coreconfigitem('server', 'uncompressedallowsecret',
     default=False,
 )
 coreconfigitem('server', 'validate',
     default=False,
 )
 coreconfigitem('server', 'zliblevel',
     default=-1,
 )
 coreconfigitem('smtp', 'host',
     default=None,
 )
 coreconfigitem('smtp', 'local_hostname',
     default=None,
 )
 coreconfigitem('smtp', 'password',
     default=None,
 )
 coreconfigitem('smtp', 'port',
     default=dynamicdefault,
 )
 coreconfigitem('smtp', 'tls',
     default='none',
 )
 coreconfigitem('smtp', 'username',
     default=None,
 )
 coreconfigitem('sparse', 'missingwarning',
     default=True,
 )
 coreconfigitem('trusted', 'groups',
     default=list,
 )
 coreconfigitem('trusted', 'users',
     default=list,
 )
 coreconfigitem('ui', '_usedassubrepo',
     default=False,
 )
 coreconfigitem('ui', 'allowemptycommit',
     default=False,
 )
 coreconfigitem('ui', 'archivemeta',
     default=True,
 )
 coreconfigitem('ui', 'askusername',
     default=False,
 )
 coreconfigitem('ui', 'clonebundlefallback',
     default=False,
 )
 coreconfigitem('ui', 'clonebundleprefers',
     default=list,
 )
 coreconfigitem('ui', 'clonebundles',
     default=True,
 )
 coreconfigitem('ui', 'color',
     default='auto',
 )
 coreconfigitem('ui', 'commitsubrepos',
     default=False,
 )
 coreconfigitem('ui', 'debug',
     default=False,
 )
 coreconfigitem('ui', 'debugger',
     default=None,
 )
 coreconfigitem('ui', 'fallbackencoding',
     default=None,
 )
 coreconfigitem('ui', 'forcecwd',
     default=None,
 )
 coreconfigitem('ui', 'forcemerge',
     default=None,
 )
 coreconfigitem('ui', 'formatdebug',
     default=False,
 )
 coreconfigitem('ui', 'formatjson',
     default=False,
 )
 coreconfigitem('ui', 'formatted',
     default=None,
 )
 coreconfigitem('ui', 'graphnodetemplate',
     default=None,
 )
 coreconfigitem('ui', 'http2debuglevel',
     default=None,
 )
 coreconfigitem('ui', 'interactive',
     default=None,
 )
 coreconfigitem('ui', 'interface',
     default=None,
 )
 coreconfigitem('ui', 'logblockedtimes',
     default=False,
 )
 coreconfigitem('ui', 'logtemplate',
     default=None,
 )
 coreconfigitem('ui', 'merge',
     default=None,
 )
 coreconfigitem('ui', 'mergemarkers',
     default='basic',
 )
 coreconfigitem('ui', 'mergemarkertemplate',
     default=('{node|short} '
             '{ifeq(tags, "tip", "", '
             'ifeq(tags, "", "", "{tags} "))}'
             '{if(bookmarks, "{bookmarks} ")}'
             '{ifeq(branch, "default", "", "{branch} ")}'
             '- {author|user}: {desc|firstline}')
 )
 coreconfigitem('ui', 'nontty',
     default=False,
 )
 coreconfigitem('ui', 'origbackuppath',
     default=None,
 )
 coreconfigitem('ui', 'paginate',
     default=True,
 )
 coreconfigitem('ui', 'patch',
     default=None,
 )
 coreconfigitem('ui', 'portablefilenames',
     default='warn',
 )
 coreconfigitem('ui', 'promptecho',
     default=False,
 )
 coreconfigitem('ui', 'quiet',
     default=False,
 )
 coreconfigitem('ui', 'quietbookmarkmove',
     default=False,
 )
 coreconfigitem('ui', 'remotecmd',
     default='hg',
 )
 coreconfigitem('ui', 'report_untrusted',
     default=True,
 )
 coreconfigitem('ui', 'rollback',
     default=True,
 )
 coreconfigitem('ui', 'slash',
     default=False,
 )
 coreconfigitem('ui', 'ssh',
     default='ssh',
 )
 coreconfigitem('ui', 'statuscopies',
     default=False,
 )
 coreconfigitem('ui', 'strict',
     default=False,
 )
 coreconfigitem('ui', 'style',
     default='',
 )
 coreconfigitem('ui', 'supportcontact',
     default=None,
 )
 coreconfigitem('ui', 'textwidth',
     default=78,
 )
 coreconfigitem('ui', 'timeout',
     default='600',
 )
 coreconfigitem('ui', 'traceback',
     default=False,
 )
 coreconfigitem('ui', 'tweakdefaults',
     default=False,
 )
 coreconfigitem('ui', 'usehttp2',
     default=False,
 )
 coreconfigitem('ui', 'username',
     alias=[('ui', 'user')]
 )
 coreconfigitem('ui', 'verbose',
     default=False,
 )
 coreconfigitem('verify', 'skipflags',
     default=None,
 )
 coreconfigitem('web', 'accesslog',
     default='-',
 )
 coreconfigitem('web', 'address',
     default='',
 )
 coreconfigitem('web', 'allow_archive',
     default=list,
 )
 coreconfigitem('web', 'allow_read',
     default=list,
 )
 coreconfigitem('web', 'baseurl',
     default=None,
 )
 coreconfigitem('web', 'cacerts',
     default=None,
 )
 coreconfigitem('web', 'certificate',
     default=None,
 )
 coreconfigitem('web', 'collapse',
     default=False,
 )
 coreconfigitem('web', 'csp',
     default=None,
 )
 coreconfigitem('web', 'deny_read',
     default=list,
 )
 coreconfigitem('web', 'descend',
     default=True,
 )
 coreconfigitem('web', 'description',
     default="",
 )
 coreconfigitem('web', 'encoding',
     default=lambda: encoding.encoding,
 )
 coreconfigitem('web', 'errorlog',
     default='-',
 )
 coreconfigitem('web', 'ipv6',
     default=False,
 )
 coreconfigitem('web', 'port',
     default=8000,
 )
 coreconfigitem('web', 'prefix',
     default='',
 )
+coreconfigitem('web', 'push_ssl',
+    default=True,
+)
 coreconfigitem('web', 'refreshinterval',
     default=20,
 )
 coreconfigitem('web', 'stripes',
     default=1,
 )
 coreconfigitem('web', 'style',
     default='paper',
 )
 coreconfigitem('web', 'templates',
     default=None,
 )
 coreconfigitem('web', 'view',
     default='served',
 )
 coreconfigitem('worker', 'backgroundclose',
     default=dynamicdefault,
 )
 # Windows defaults to a limit of 512 open files. A buffer of 128
 # should give us enough headway.
 coreconfigitem('worker', 'backgroundclosemaxqueue',
     default=384,
 )
 coreconfigitem('worker', 'backgroundcloseminfilecount',
     default=2048,
 )
 coreconfigitem('worker', 'backgroundclosethreadcount',
     default=4,
 )
 coreconfigitem('worker', 'numcpus',
     default=None,
 )

mercurial/hgweb/common.py

@@ -1,233 +1,233 b''
 # hgweb/common.py - Utility functions needed by hgweb_mod and hgwebdir_mod
 #
 # Copyright 21 May 2005 - (c) 2005 Jake Edge <[e-mail]>
 # Copyright 2005, 2006 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2 or any later version.
 
 from __future__ import absolute_import
 
 import base64
 import errno
 import mimetypes
 import os
 import uuid
 
 from .. import (
     encoding,
     pycompat,
     util,
 )
 
 httpserver = util.httpserver
 
 HTTP_OK = 200
 HTTP_NOT_MODIFIED = 304
 HTTP_BAD_REQUEST = 400
 HTTP_UNAUTHORIZED = 401
 HTTP_FORBIDDEN = 403
 HTTP_NOT_FOUND = 404
 HTTP_METHOD_NOT_ALLOWED = 405
 HTTP_SERVER_ERROR = 500
 
 
 def ismember(ui, username, userlist):
     """Check if username is a member of userlist.
 
     If userlist has a single '*' member, all users are considered members.
     Can be overridden by extensions to provide more complex authorization
     schemes.
     """
     return userlist == ['*'] or username in userlist
 
 def checkauthz(hgweb, req, op):
     '''Check permission for operation based on request data (including
     authentication info). Return if op allowed, else raise an ErrorResponse
     exception.'''
 
     user = req.env.get('REMOTE_USER')
 
     deny_read = hgweb.configlist('web', 'deny_read')
     if deny_read and (not user or ismember(hgweb.repo.ui, user, deny_read)):
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'read not authorized')
 
     allow_read = hgweb.configlist('web', 'allow_read')
     if allow_read and (not ismember(hgweb.repo.ui, user, allow_read)):
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'read not authorized')
 
     if op == 'pull' and not hgweb.allowpull:
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'pull not authorized')
     elif op == 'pull' or op is None: # op is None for interface requests
         return
 
     # enforce that you can only push using POST requests
     if req.env['REQUEST_METHOD'] != 'POST':
         msg = 'push requires POST request'
         raise ErrorResponse(HTTP_METHOD_NOT_ALLOWED, msg)
 
     # require ssl by default for pushing, auth info cannot be sniffed
     # and replayed
     scheme = req.env.get('wsgi.url_scheme')
-    if hgweb.configbool('web', 'push_ssl', True) and scheme != 'https':
+    if hgweb.configbool('web', 'push_ssl') and scheme != 'https':
         raise ErrorResponse(HTTP_FORBIDDEN, 'ssl required')
 
     deny = hgweb.configlist('web', 'deny_push')
     if deny and (not user or ismember(hgweb.repo.ui, user, deny)):
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'push not authorized')
 
     allow = hgweb.configlist('web', 'allow_push')
     if not (allow and ismember(hgweb.repo.ui, user, allow)):
         raise ErrorResponse(HTTP_UNAUTHORIZED, 'push not authorized')
 
 # Hooks for hgweb permission checks; extensions can add hooks here.
 # Each hook is invoked like this: hook(hgweb, request, operation),
 # where operation is either read, pull or push. Hooks should either
 # raise an ErrorResponse exception, or just return.
 #
 # It is possible to do both authentication and authorization through
 # this.
 permhooks = [checkauthz]
 
 
 class ErrorResponse(Exception):
     def __init__(self, code, message=None, headers=None):
         if message is None:
             message = _statusmessage(code)
         Exception.__init__(self, message)
         self.code = code
         if headers is None:
             headers = []
         self.headers = headers
 
 class continuereader(object):
     def __init__(self, f, write):
         self.f = f
         self._write = write
         self.continued = False
 
     def read(self, amt=-1):
         if not self.continued:
             self.continued = True
             self._write('HTTP/1.1 100 Continue\r\n\r\n')
         return self.f.read(amt)
 
     def __getattr__(self, attr):
         if attr in ('close', 'readline', 'readlines', '__iter__'):
             return getattr(self.f, attr)
         raise AttributeError
 
 def _statusmessage(code):
     responses = httpserver.basehttprequesthandler.responses
     return responses.get(code, ('Error', 'Unknown error'))[0]
 
 def statusmessage(code, message=None):
     return '%d %s' % (code, message or _statusmessage(code))
 
 def get_stat(spath, fn):
     """stat fn if it exists, spath otherwise"""
     cl_path = os.path.join(spath, fn)
     if os.path.exists(cl_path):
         return os.stat(cl_path)
     else:
         return os.stat(spath)
 
 def get_mtime(spath):
     return get_stat(spath, "00changelog.i").st_mtime
 
 def ispathsafe(path):
     """Determine if a path is safe to use for filesystem access."""
     parts = path.split('/')
     for part in parts:
         if (part in ('', os.curdir, os.pardir) or
             pycompat.ossep in part or
             pycompat.osaltsep is not None and pycompat.osaltsep in part):
             return False
 
     return True
 
 def staticfile(directory, fname, req):
     """return a file inside directory with guessed Content-Type header
 
     fname always uses '/' as directory separator and isn't allowed to
     contain unusual path components.
     Content-Type is guessed using the mimetypes module.
     Return an empty string if fname is illegal or file not found.
 
     """
     if not ispathsafe(fname):
         return
 
     fpath = os.path.join(*fname.split('/'))
     if isinstance(directory, str):
         directory = [directory]
     for d in directory:
         path = os.path.join(d, fpath)
         if os.path.exists(path):
             break
     try:
         os.stat(path)
         ct = mimetypes.guess_type(path)[0] or "text/plain"
         with open(path, 'rb') as fh:
             data = fh.read()
 
         req.respond(HTTP_OK, ct, body=data)
     except TypeError:
         raise ErrorResponse(HTTP_SERVER_ERROR, 'illegal filename')
     except OSError as err:
         if err.errno == errno.ENOENT:
             raise ErrorResponse(HTTP_NOT_FOUND)
         else:
             raise ErrorResponse(HTTP_SERVER_ERROR,
                                 encoding.strtolocal(err.strerror))
 
 def paritygen(stripecount, offset=0):
     """count parity of horizontal stripes for easier reading"""
     if stripecount and offset:
         # account for offset, e.g. due to building the list in reverse
         count = (stripecount + offset) % stripecount
         parity = (stripecount + offset) / stripecount & 1
     else:
         count = 0
         parity = 0
     while True:
         yield parity
         count += 1
         if stripecount and count >= stripecount:
             parity = 1 - parity
             count = 0
 
 def get_contact(config):
     """Return repo contact information or empty string.
 
     web.contact is the primary source, but if that is not set, try
     ui.username or $EMAIL as a fallback to display something useful.
     """
     return (config("web", "contact") or
             config("ui", "username") or
             encoding.environ.get("EMAIL") or "")
 
 def caching(web, req):
     tag = r'W/"%d"' % web.mtime
     if req.env.get('HTTP_IF_NONE_MATCH') == tag:
         raise ErrorResponse(HTTP_NOT_MODIFIED)
     req.headers.append(('ETag', tag))
 
 def cspvalues(ui):
     """Obtain the Content-Security-Policy header and nonce value.
 
     Returns a 2-tuple of the CSP header value and the nonce value.
 
     First value is ``None`` if CSP isn't enabled. Second value is ``None``
     if CSP isn't enabled or if the CSP header doesn't need a nonce.
     """
     # Don't allow untrusted CSP setting since it be disable protections
     # from a trusted/global source.
     csp = ui.config('web', 'csp', untrusted=False)
     nonce = None
 
     if csp and '%nonce%' in csp:
         nonce = base64.urlsafe_b64encode(uuid.uuid4().bytes).rstrip('=')
         csp = csp.replace('%nonce%', nonce)
 
     return csp, nonce