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)