# Copyright (C) 2003-2007, 2009-2011 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 GENERATE range conversion.""" import dns def from_text(text): """Convert the text form of a range in a GENERATE statement to an integer. @param text: the textual range @type text: string @return: The start, stop and step values. @rtype: tuple """ # TODO, figure out the bounds on start, stop and step. step = 1 cur = '' state = 0 # state 0 1 2 3 4 # x - y / z if text and text[0] == '-': raise dns.exception.SyntaxError("Start cannot be a negative number") for c in text: if c == '-' and state == 0: start = int(cur) cur = '' state = 2 elif c == '/': stop = int(cur) cur = '' state = 4 elif c.isdigit(): cur += c else: raise dns.exception.SyntaxError("Could not parse %s" % (c)) if state in (1, 3): raise dns.exception.SyntaxError() if state == 2: stop = int(cur) if state == 4: step = int(cur) assert step >= 1 assert start >= 0 assert start <= stop # TODO, can start == stop? return (start, stop, step)