From 4bbc3ff037026c72f3249f59c1b5af69a6ad6d69 Mon Sep 17 00:00:00 2001 From: Jelmer Vernooij Date: Mon, 29 Mar 2010 16:08:11 +0200 Subject: s4-python: Move dnspython to lib/, like the other Python modules This also avoids it from being installed if it's already present on the system. --- lib/dnspython/dns/flags.py | 106 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 106 insertions(+) create mode 100644 lib/dnspython/dns/flags.py (limited to 'lib/dnspython/dns/flags.py') diff --git a/lib/dnspython/dns/flags.py b/lib/dnspython/dns/flags.py new file mode 100644 index 0000000000..79375ea2ce --- /dev/null +++ b/lib/dnspython/dns/flags.py @@ -0,0 +1,106 @@ +# Copyright (C) 2001-2007, 2009, 2010 Nominum, Inc. +# +# Permission to use, copy, modify, and distribute this software and its +# documentation for any purpose with or without fee is hereby granted, +# provided that the above copyright notice and this permission notice +# appear in all copies. +# +# THE SOFTWARE IS PROVIDED "AS IS" AND NOMINUM DISCLAIMS ALL WARRANTIES +# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL NOMINUM BE LIABLE FOR +# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT +# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + +"""DNS Message Flags.""" + +# Standard DNS flags + +QR = 0x8000 +AA = 0x0400 +TC = 0x0200 +RD = 0x0100 +RA = 0x0080 +AD = 0x0020 +CD = 0x0010 + +# EDNS flags + +DO = 0x8000 + +_by_text = { + 'QR' : QR, + 'AA' : AA, + 'TC' : TC, + 'RD' : RD, + 'RA' : RA, + 'AD' : AD, + 'CD' : CD +} + +_edns_by_text = { + 'DO' : DO +} + + +# We construct the inverse mappings programmatically to ensure that we +# cannot make any mistakes (e.g. omissions, cut-and-paste errors) that +# would cause the mappings not to be true inverses. + +_by_value = dict([(y, x) for x, y in _by_text.iteritems()]) + +_edns_by_value = dict([(y, x) for x, y in _edns_by_text.iteritems()]) + +def _order_flags(table): + order = list(table.iteritems()) + order.sort() + order.reverse() + return order + +_flags_order = _order_flags(_by_value) + +_edns_flags_order = _order_flags(_edns_by_value) + +def _from_text(text, table): + flags = 0 + tokens = text.split() + for t in tokens: + flags = flags | table[t.upper()] + return flags + +def _to_text(flags, table, order): + text_flags = [] + for k, v in order: + if flags & k != 0: + text_flags.append(v) + return ' '.join(text_flags) + +def from_text(text): + """Convert a space-separated list of flag text values into a flags + value. + @rtype: int""" + + return _from_text(text, _by_text) + +def to_text(flags): + """Convert a flags value into a space-separated list of flag text + values. + @rtype: string""" + + return _to_text(flags, _by_value, _flags_order) + + +def edns_from_text(text): + """Convert a space-separated list of EDNS flag text values into a EDNS + flags value. + @rtype: int""" + + return _from_text(text, _edns_by_text) + +def edns_to_text(flags): + """Convert an EDNS flags value into a space-separated list of EDNS flag + text values. + @rtype: string""" + + return _to_text(flags, _edns_by_value, _edns_flags_order) -- cgit