Source code for pytomo.dns.rdtypes.txtbase

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"""TXT-like base class."""

from __future__ import absolute_import

from .. import exception as dns_exception
from .. import rdata as dns_rdata
#from .. import tokenizer as dns_tokenizer

[docs]class TXTBase(dns_rdata.Rdata): """Base class for rdata that is like a TXT record @ivar strings: the text strings @type strings: list of string @see: RFC 1035""" __slots__ = ['strings'] def __init__(self, rdclass, rdtype, strings): super(TXTBase, self).__init__(rdclass, rdtype) if isinstance(strings, str): strings = [ strings ] self.strings = strings[:]
[docs] def to_text(self, origin=None, relativize=True, **kw): txt = '' prefix = '' for s in self.strings: txt += '%s"%s"' % (prefix, dns_rdata._escapify(s)) prefix = ' ' return txt
[docs] def from_text(cls, rdclass, rdtype, tok, origin = None, relativize = True): strings = [] while 1: token = tok.get().unescape() if token.is_eol_or_eof(): break if not (token.is_quoted_string() or token.is_identifier()): raise dns_exception.SyntaxError("expected a string") if len(token.value) > 255: raise dns_exception.SyntaxError("string too long") strings.append(token.value) if len(strings) == 0: raise dns_exception.UnexpectedEnd return cls(rdclass, rdtype, strings)
from_text = classmethod(from_text)
[docs] def to_wire(self, file, compress = None, origin = None): for s in self.strings: l = len(s) assert l < 256 byte = chr(l) file.write(byte) file.write(s)
[docs] def from_wire(cls, rdclass, rdtype, wire, current, rdlen, origin = None): strings = [] while rdlen > 0: l = ord(wire[current]) current += 1 rdlen -= 1 if l > rdlen: raise dns_exception.FormError s = wire[current : current + l] current += l rdlen -= l strings.append(s) return cls(rdclass, rdtype, strings)
from_wire = classmethod(from_wire) def _cmp(self, other): return cmp(self.strings, other.strings)