| # Copyright (C) 2001-2010 Python Software Foundation | 
 | # Author: Barry Warsaw | 
 | # Contact: email-sig@python.org | 
 |  | 
 | """Miscellaneous utilities.""" | 
 |  | 
 | __all__ = [ | 
 |     'collapse_rfc2231_value', | 
 |     'decode_params', | 
 |     'decode_rfc2231', | 
 |     'encode_rfc2231', | 
 |     'formataddr', | 
 |     'formatdate', | 
 |     'getaddresses', | 
 |     'make_msgid', | 
 |     'mktime_tz', | 
 |     'parseaddr', | 
 |     'parsedate', | 
 |     'parsedate_tz', | 
 |     'unquote', | 
 |     ] | 
 |  | 
 | import os | 
 | import re | 
 | import time | 
 | import base64 | 
 | import random | 
 | import socket | 
 | import urllib | 
 | import warnings | 
 |  | 
 | from email._parseaddr import quote | 
 | from email._parseaddr import AddressList as _AddressList | 
 | from email._parseaddr import mktime_tz | 
 |  | 
 | # We need wormarounds for bugs in these methods in older Pythons (see below) | 
 | from email._parseaddr import parsedate as _parsedate | 
 | from email._parseaddr import parsedate_tz as _parsedate_tz | 
 |  | 
 | from quopri import decodestring as _qdecode | 
 |  | 
 | # Intrapackage imports | 
 | from email.encoders import _bencode, _qencode | 
 |  | 
 | COMMASPACE = ', ' | 
 | EMPTYSTRING = '' | 
 | UEMPTYSTRING = u'' | 
 | CRLF = '\r\n' | 
 | TICK = "'" | 
 |  | 
 | specialsre = re.compile(r'[][\\()<>@,:;".]') | 
 | escapesre = re.compile(r'[][\\()"]') | 
 |  | 
 |  | 
 |  | 
 | # Helpers | 
 |  | 
 | def _identity(s): | 
 |     return s | 
 |  | 
 |  | 
 | def _bdecode(s): | 
 |     """Decodes a base64 string. | 
 |  | 
 |     This function is equivalent to base64.decodestring and it's retained only | 
 |     for backward compatibility. It used to remove the last \n of the decoded | 
 |     string, if it had any (see issue 7143). | 
 |     """ | 
 |     if not s: | 
 |         return s | 
 |     return base64.decodestring(s) | 
 |  | 
 |  | 
 |  | 
 | def fix_eols(s): | 
 |     """Replace all line-ending characters with \r\n.""" | 
 |     # Fix newlines with no preceding carriage return | 
 |     s = re.sub(r'(?<!\r)\n', CRLF, s) | 
 |     # Fix carriage returns with no following newline | 
 |     s = re.sub(r'\r(?!\n)', CRLF, s) | 
 |     return s | 
 |  | 
 |  | 
 |  | 
 | def formataddr(pair): | 
 |     """The inverse of parseaddr(), this takes a 2-tuple of the form | 
 |     (realname, email_address) and returns the string value suitable | 
 |     for an RFC 2822 From, To or Cc header. | 
 |  | 
 |     If the first element of pair is false, then the second element is | 
 |     returned unmodified. | 
 |     """ | 
 |     name, address = pair | 
 |     if name: | 
 |         quotes = '' | 
 |         if specialsre.search(name): | 
 |             quotes = '"' | 
 |         name = escapesre.sub(r'\\\g<0>', name) | 
 |         return '%s%s%s <%s>' % (quotes, name, quotes, address) | 
 |     return address | 
 |  | 
 |  | 
 |  | 
 | def getaddresses(fieldvalues): | 
 |     """Return a list of (REALNAME, EMAIL) for each fieldvalue.""" | 
 |     all = COMMASPACE.join(fieldvalues) | 
 |     a = _AddressList(all) | 
 |     return a.addresslist | 
 |  | 
 |  | 
 |  | 
 | ecre = re.compile(r''' | 
 |   =\?                   # literal =? | 
 |   (?P<charset>[^?]*?)   # non-greedy up to the next ? is the charset | 
 |   \?                    # literal ? | 
 |   (?P<encoding>[qb])    # either a "q" or a "b", case insensitive | 
 |   \?                    # literal ? | 
 |   (?P<atom>.*?)         # non-greedy up to the next ?= is the atom | 
 |   \?=                   # literal ?= | 
 |   ''', re.VERBOSE | re.IGNORECASE) | 
 |  | 
 |  | 
 |  | 
 | def formatdate(timeval=None, localtime=False, usegmt=False): | 
 |     """Returns a date string as specified by RFC 2822, e.g.: | 
 |  | 
 |     Fri, 09 Nov 2001 01:08:47 -0000 | 
 |  | 
 |     Optional timeval if given is a floating point time value as accepted by | 
 |     gmtime() and localtime(), otherwise the current time is used. | 
 |  | 
 |     Optional localtime is a flag that when True, interprets timeval, and | 
 |     returns a date relative to the local timezone instead of UTC, properly | 
 |     taking daylight savings time into account. | 
 |  | 
 |     Optional argument usegmt means that the timezone is written out as | 
 |     an ascii string, not numeric one (so "GMT" instead of "+0000"). This | 
 |     is needed for HTTP, and is only used when localtime==False. | 
 |     """ | 
 |     # Note: we cannot use strftime() because that honors the locale and RFC | 
 |     # 2822 requires that day and month names be the English abbreviations. | 
 |     if timeval is None: | 
 |         timeval = time.time() | 
 |     if localtime: | 
 |         now = time.localtime(timeval) | 
 |         # Calculate timezone offset, based on whether the local zone has | 
 |         # daylight savings time, and whether DST is in effect. | 
 |         if time.daylight and now[-1]: | 
 |             offset = time.altzone | 
 |         else: | 
 |             offset = time.timezone | 
 |         hours, minutes = divmod(abs(offset), 3600) | 
 |         # Remember offset is in seconds west of UTC, but the timezone is in | 
 |         # minutes east of UTC, so the signs differ. | 
 |         if offset > 0: | 
 |             sign = '-' | 
 |         else: | 
 |             sign = '+' | 
 |         zone = '%s%02d%02d' % (sign, hours, minutes // 60) | 
 |     else: | 
 |         now = time.gmtime(timeval) | 
 |         # Timezone offset is always -0000 | 
 |         if usegmt: | 
 |             zone = 'GMT' | 
 |         else: | 
 |             zone = '-0000' | 
 |     return '%s, %02d %s %04d %02d:%02d:%02d %s' % ( | 
 |         ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'][now[6]], | 
 |         now[2], | 
 |         ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', | 
 |          'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'][now[1] - 1], | 
 |         now[0], now[3], now[4], now[5], | 
 |         zone) | 
 |  | 
 |  | 
 |  | 
 | def make_msgid(idstring=None): | 
 |     """Returns a string suitable for RFC 2822 compliant Message-ID, e.g: | 
 |  | 
 |     <20020201195627.33539.96671@nightshade.la.mastaler.com> | 
 |  | 
 |     Optional idstring if given is a string used to strengthen the | 
 |     uniqueness of the message id. | 
 |     """ | 
 |     timeval = time.time() | 
 |     utcdate = time.strftime('%Y%m%d%H%M%S', time.gmtime(timeval)) | 
 |     pid = os.getpid() | 
 |     randint = random.randrange(100000) | 
 |     if idstring is None: | 
 |         idstring = '' | 
 |     else: | 
 |         idstring = '.' + idstring | 
 |     idhost = socket.getfqdn() | 
 |     msgid = '<%s.%s.%s%s@%s>' % (utcdate, pid, randint, idstring, idhost) | 
 |     return msgid | 
 |  | 
 |  | 
 |  | 
 | # These functions are in the standalone mimelib version only because they've | 
 | # subsequently been fixed in the latest Python versions.  We use this to worm | 
 | # around broken older Pythons. | 
 | def parsedate(data): | 
 |     if not data: | 
 |         return None | 
 |     return _parsedate(data) | 
 |  | 
 |  | 
 | def parsedate_tz(data): | 
 |     if not data: | 
 |         return None | 
 |     return _parsedate_tz(data) | 
 |  | 
 |  | 
 | def parseaddr(addr): | 
 |     addrs = _AddressList(addr).addresslist | 
 |     if not addrs: | 
 |         return '', '' | 
 |     return addrs[0] | 
 |  | 
 |  | 
 | # rfc822.unquote() doesn't properly de-backslash-ify in Python pre-2.3. | 
 | def unquote(str): | 
 |     """Remove quotes from a string.""" | 
 |     if len(str) > 1: | 
 |         if str.startswith('"') and str.endswith('"'): | 
 |             return str[1:-1].replace('\\\\', '\\').replace('\\"', '"') | 
 |         if str.startswith('<') and str.endswith('>'): | 
 |             return str[1:-1] | 
 |     return str | 
 |  | 
 |  | 
 |  | 
 | # RFC2231-related functions - parameter encoding and decoding | 
 | def decode_rfc2231(s): | 
 |     """Decode string according to RFC 2231""" | 
 |     parts = s.split(TICK, 2) | 
 |     if len(parts) <= 2: | 
 |         return None, None, s | 
 |     return parts | 
 |  | 
 |  | 
 | def encode_rfc2231(s, charset=None, language=None): | 
 |     """Encode string according to RFC 2231. | 
 |  | 
 |     If neither charset nor language is given, then s is returned as-is.  If | 
 |     charset is given but not language, the string is encoded using the empty | 
 |     string for language. | 
 |     """ | 
 |     import urllib | 
 |     s = urllib.quote(s, safe='') | 
 |     if charset is None and language is None: | 
 |         return s | 
 |     if language is None: | 
 |         language = '' | 
 |     return "%s'%s'%s" % (charset, language, s) | 
 |  | 
 |  | 
 | rfc2231_continuation = re.compile(r'^(?P<name>\w+)\*((?P<num>[0-9]+)\*?)?$') | 
 |  | 
 | def decode_params(params): | 
 |     """Decode parameters list according to RFC 2231. | 
 |  | 
 |     params is a sequence of 2-tuples containing (param name, string value). | 
 |     """ | 
 |     # Copy params so we don't mess with the original | 
 |     params = params[:] | 
 |     new_params = [] | 
 |     # Map parameter's name to a list of continuations.  The values are a | 
 |     # 3-tuple of the continuation number, the string value, and a flag | 
 |     # specifying whether a particular segment is %-encoded. | 
 |     rfc2231_params = {} | 
 |     name, value = params.pop(0) | 
 |     new_params.append((name, value)) | 
 |     while params: | 
 |         name, value = params.pop(0) | 
 |         if name.endswith('*'): | 
 |             encoded = True | 
 |         else: | 
 |             encoded = False | 
 |         value = unquote(value) | 
 |         mo = rfc2231_continuation.match(name) | 
 |         if mo: | 
 |             name, num = mo.group('name', 'num') | 
 |             if num is not None: | 
 |                 num = int(num) | 
 |             rfc2231_params.setdefault(name, []).append((num, value, encoded)) | 
 |         else: | 
 |             new_params.append((name, '"%s"' % quote(value))) | 
 |     if rfc2231_params: | 
 |         for name, continuations in rfc2231_params.items(): | 
 |             value = [] | 
 |             extended = False | 
 |             # Sort by number | 
 |             continuations.sort() | 
 |             # And now append all values in numerical order, converting | 
 |             # %-encodings for the encoded segments.  If any of the | 
 |             # continuation names ends in a *, then the entire string, after | 
 |             # decoding segments and concatenating, must have the charset and | 
 |             # language specifiers at the beginning of the string. | 
 |             for num, s, encoded in continuations: | 
 |                 if encoded: | 
 |                     s = urllib.unquote(s) | 
 |                     extended = True | 
 |                 value.append(s) | 
 |             value = quote(EMPTYSTRING.join(value)) | 
 |             if extended: | 
 |                 charset, language, value = decode_rfc2231(value) | 
 |                 new_params.append((name, (charset, language, '"%s"' % value))) | 
 |             else: | 
 |                 new_params.append((name, '"%s"' % value)) | 
 |     return new_params | 
 |  | 
 | def collapse_rfc2231_value(value, errors='replace', | 
 |                            fallback_charset='us-ascii'): | 
 |     if isinstance(value, tuple): | 
 |         rawval = unquote(value[2]) | 
 |         charset = value[0] or 'us-ascii' | 
 |         try: | 
 |             return unicode(rawval, charset, errors) | 
 |         except LookupError: | 
 |             # XXX charset is unknown to Python. | 
 |             return unicode(rawval, fallback_charset, errors) | 
 |     else: | 
 |         return unquote(value) |