samba-mirror/lib/dnspython/dns/ipv4.py

# Copyright (C) 2003-2007, 2009-2011 Nominum, Inc.
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# provided that the above copyright notice and this permission notice
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# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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"""IPv4 helper functions."""

import struct

import dns.exception

def inet_ntoa(address):
    if len(address) != 4:
        raise dns.exception.SyntaxError
    return '%u.%u.%u.%u' % (ord(address[0]), ord(address[1]),
                            ord(address[2]), ord(address[3]))

def inet_aton(text):
    parts = text.split('.')
    if len(parts) != 4:
        raise dns.exception.SyntaxError
    for part in parts:
        if not part.isdigit():
            raise dns.exception.SyntaxError
        if len(part) > 1 and part[0] == '0':
            # No leading zeros
            raise dns.exception.SyntaxError
    try:
        bytes = [int(part) for part in parts]
        return struct.pack('BBBB', *bytes)
    except:
        raise dns.exception.SyntaxError