70 lines
2.3 KiB
Ruby
70 lines
2.3 KiB
Ruby
# $Id: misc.rb 14 2008-03-02 05:42:30Z warchild $
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#
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# Copyright (c) 2008, Jon Hart
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# All rights reserved.
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#
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# Redistribution and use in source and binary forms, with or without
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# modification, are permitted provided that the following conditions are met:
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# * Redistributions of source code must retain the above copyright
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# notice, this list of conditions and the following disclaimer.
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# * Redistributions in binary form must reproduce the above copyright
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# notice, this list of conditions and the following disclaimer in the
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# documentation and/or other materials provided with the distribution.
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# * Neither the name of the <organization> nor the
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# names of its contributors may be used to endorse or promote products
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# derived from this software without specific prior written permission.
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#
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# THIS SOFTWARE IS PROVIDED BY Jon Hart ``AS IS'' AND ANY
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# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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# DISCLAIMED. IN NO EVENT SHALL Jon Hart BE LIABLE FOR ANY
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# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#
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module Racket
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module Misc
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# Return a number that is at most size bits long
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def Misc.randbits(size)
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bits = 0
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srand Time.now.usec
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0.upto(size-1) {
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bits <<= 1
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bits |= rand(2)
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}
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bits
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end
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# Return a byte that is at most size bytes long
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def Misc.randbytes(size)
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bytes = 0
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0.upto(size-1) {
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bytes <<= 8
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bytes |= randbits(8)
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}
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bytes
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end
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# Return a string that is at most size characters long
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def Misc.randstring(size)
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s = ""
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0.upto(size-1) {
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s += sprintf("%c", randbytes(1))
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}
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s
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end
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# given a long representing a MAC address
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# print it out in human readable form
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def Misc.macaddr(long)
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long.to_s(16).rjust(12, '0').unpack("a2a2a2a2a2a2").join(":")
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end
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end
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end
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# vim: set ts=2 et sw=2:
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