kamawanu/readme.md

## readme.md

      
    Raw
  

              readme.md
            
          
    UUIDGEN
解説
Universal IDs (GUID/UUID) — CCPN Plone Site
 
Information
Generation of universal IDs is still a developing field, apparently. A quick google turns up
http://home.arcor.de/jurner/python/#pkg-uuid-0.3.1
http://sourceforge.net/tracker/index.php?func=detail&aid=1368955&group_id=5470&atid=305470
which are new since Peter sent out his summarising mail
For the time being I am using the uuid generator from
https://lists.ubuntu.com/archives/bazaar-ng/2005q2/000285.html
Universally Unique Identifier - Wikipedia, the free encyclopedia
Pure RUBY
UUIDTools
Copyright (c) 2005 Robert Aman # # Permission is hereby granted ...
 
RubyForge: UUIDTools: Project Info
Pure PHP
/trunk/htdocs/system/classes/uuid.php - Habari - Trac
 http://trac.habariproject.org/habari/browser/trunk/htdocs/system/classes/uuid.php?rev=608&format=txt 単純なmt_randの連続実行
PECL :: Package :: uuid
UUID.php
 

## uuidgen.php
<?php # vim:ts=2:sw=2:noet:
/* Copyright (c) 2007, OmniTI Computer Consulting, Inc.
 * All Rights Reserved.
 * For licensing information, see:
 * http://labs.omniti.com/alexandria/trunk/LICENSE
 */

/**
 * A class for working with RFC 4122 UUIDs
 */
class OmniTI_Util_UUID {
	public $binary;

	function __construct($src = null) {
		if ($src !== null) {
			switch (strlen($src)) {
				case 36: /* with -'s */
					$src = str_replace('-', '', $src);
				case 32: /* with -'s stripped */
					$this->binary = pack('H*', $src);
					break;
				case 16: /* binary string */
					$this->binary = $src;
					break;
				case 24: /* base64 encoded binary */
					$this->binary = base64_decode(
						str_replace(
							array('@', '-', '_'),
							array('=', '/', '+'),
							$src));
					break;
				default:
					$this->binary = null;
			}
		} else {
			$this->generate();
		}
	}

	/**
	 * returns a 32-bit integer that identifies this host.
	 * The node identifier needs to be unique among nodes
	 * in a cluster for a given application in order to
	 * avoid collisions between generated identifiers.
	 * You may extend and override this method if you
	 * want to substitute an alternative means of determining
	 * the node identifier */
	protected function getNodeId() {
		if (isset($_SERVER['SERVER_ADDR'])) {
			$node = ip2long($_SERVER['SERVER_ADDR']);
		} else {
			/* running from the CLI most likely;
			 * inspect the environment to see if we can
			 * deduce the hostname, and from there, the
			 * IP address */
			static $names = array('HOSTNAME', 'HOST');
			foreach ($names as $name) {
				if (isset($_ENV[$name])) {
					$host = $_ENV[$name];
				} else {
					$host = getenv($name);
				}
				if (strlen($host)) break;
			}
			if (!strlen($host)) {
				// punt
				$node = ip2long('127.0.0.1');
			} else {
				$ip = gethostbyname($host);
				if (strlen($ip)) {
					$node = ip2long($ip);
				} else {
					// punt
					$node = crc32($host);
				}
			}
		}
		return $node;
	}

	/**
	 * returns a process identifier.
	 * In multi-process servers, this should be the system process ID.
	 * In multi-threaded servers, this should be some unique ID to
	 * prevent two threads from generating precisely the same UUID
	 * at the same time.
	 */
	protected function getLockId() {
		if (function_exists('zend_thread_id')) {
			return zend_thread_id();
		}
		return getmypid();
	}

	/**
	 * generate an RFC 4122 UUID.
	 * This is psuedo-random UUID influenced by the system clock, IP
	 * address and process ID.
	 *
	 * The intended use is to generate an identifier that can uniquely
	 * identify user generated posts, comments etc. made to a website.
	 * This generation process should be sufficient to avoid collisions
	 * between nodes in a cluster, and between apache children on the
	 * same host.
	 *
	 */
	function generate() {
		$node = $this->getNodeId();
		$pid = $this->getLockId();

		list($time_mid, $time_lo) = explode(' ', microtime());
		$time_lo = (int)$time_lo;
		$time_mid = (int)substr($time_mid, 2);

		$time_hi = mt_rand(0, 0xfff);
		/* version 4 UUID */
		$time_hi |= 0x4000;

		$clock_lo = mt_rand(0, 0xff);
		$node_lo = $pid;

		/* type is psuedo-random */
		$clock_hi = mt_rand(0, 0x3f);
		$clock_hi |= 0x80;

		$this->binary = pack('NnnCCnN',
			$time_lo, $time_mid & 0xffff, $time_hi,
			$clock_hi, $clock_lo, $node_lo, $node);
	}

	/**
	 * render the UUID as an RFC4122 standard string representation
	 * of the binary bits.
	 */
	function toRFC4122String() {
		$uuid = unpack('Ntl/ntm/nth/Cch/Ccl/nnl/Nn', $this->binary);
		return sprintf("%08x-%04x-%04x-%02x%02x-%04x%08x",
			$uuid['tl'], $uuid['tm'], $uuid['th'],
			$uuid['ch'], $uuid['cl'], $uuid['nl'], $uuid['n']);
	}

	/**
	 * render the UUID using a modified base64 representation
	 * of the binary bits.  This string is shorter than the standard
	 * representation, but is not part of any standard specification.
	 */
	function toShortString() {
		return str_replace(
				array('=', '/', '+'),
				array('@', '-', '_'),
				base64_encode($this->binary));
	}
}

?>

## uuidgen.rb
#--
# Copyright (c) 2005 Robert Aman
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#++

UUID_TOOLS_VERSION = "1.0.0"

$:.unshift(File.dirname(__FILE__))

require 'uri'
require 'time'
require 'thread'
require 'digest/sha1'
require 'digest/md5'

#  Because it's impossible to hype a UUID generator on its genuine merits,
#  I give you... Really bad ASCII art in the comments:
#
#
#                \
#                /
#               +
#              ]
#              ]
#              |
#             /
#           Mp___
#              `~0NNp,
#               __ggM'
#             g0M~"`
#            ]0M*-
#
#                    ___
#                _g000M00g,
#              j0M~      ~M&
#            j0M"          ~N,
#           j0P              M&
#          jM                  1
#         j0                   ]1
#        .0P                    0,
#        00'                    M&
#        0M                     ]0L
#       ]0f         ___          M0
#        M0NN0M00MMM~"'M          0&
#          `~          ~0         ]0,
#                       ]M        ]0&
#                        M&        M0,
#               ____gp_   M&        M0_
#            __p0MPM8MM&_  M/        ^0&_
#           gN"`       M0N_j0,         MM&__
#         _gF           `~M0P`   __      M00g
#        g0'                    gM0&,     ~M0&
#      _pM`                     0, ]M1     "00&
#     _00                    /g1MMgj01      ]0MI
#    _0F                     t"M,7MMM        00I
#   g0'                  _   N&j&            40'
#  g0'                _p0Mq_   '             N0QQNM#g,
#  0'              _g0000000g__              ~M@MMM000g
#  f             _jM00@`  ~M0000Mgppg,             "P00&
# |             g000~       `~M000000&_               ~0&
# ]M          _M00F              "00MM`                ~#&
# `0L        m000F                #E                    "0f
#   9r     j000M`                 40,                    00
#    ]0g_ j00M`                   ^M0MNggp#gqpg          M0&
#     ~MPM0f                         ~M000000000g_ ,_ygg&M00f
#                                        `~~~M00000000000000
#                                              `M0000000000f
#                                                  ~@@@MF~`
#
#

#= uuidtools.rb
#
# UUIDTools was designed to be a simple library for generating any
# of the various types of UUIDs.  It conforms to RFC 4122 whenever
# possible.
#
#== Example
#  UUID.md5_create(UUID_DNS_NAMESPACE, "www.widgets.com")
#  => #<UUID:0x287576 UUID:3d813cbb-47fb-32ba-91df-831e1593ac29>
#  UUID.sha1_create(UUID_DNS_NAMESPACE, "www.widgets.com")
#  => #<UUID:0x2a0116 UUID:21f7f8de-8051-5b89-8680-0195ef798b6a>
#  UUID.timestamp_create
#  => #<UUID:0x2adfdc UUID:64a5189c-25b3-11da-a97b-00c04fd430c8>
#  UUID.random_create
#  => #<UUID:0x19013a UUID:984265dc-4200-4f02-ae70-fe4f48964159>
class UUID
  @@mac_address = nil
  @@last_timestamp = nil
  @@last_node_id = nil
  @@last_clock_sequence = nil
  @@state_file = nil
  @@mutex = Mutex.new

  def initialize(time_low, time_mid, time_hi_and_version,
      clock_seq_hi_and_reserved, clock_seq_low, nodes)
    unless time_low >= 0 && time_low < 4294967296
      raise ArgumentError,
        "Expected unsigned 32-bit number for time_low, got #{time_low}."
    end
    unless time_mid >= 0 && time_mid < 65536
      raise ArgumentError,
        "Expected unsigned 16-bit number for time_mid, got #{time_mid}."
    end
    unless time_hi_and_version >= 0 && time_hi_and_version < 65536
      raise ArgumentError,
        "Expected unsigned 16-bit number for time_hi_and_version, " +
        "got #{time_hi_and_version}."
    end
    unless clock_seq_hi_and_reserved >= 0 && clock_seq_hi_and_reserved < 256
      raise ArgumentError,
        "Expected unsigned 8-bit number for clock_seq_hi_and_reserved, " +
        "got #{clock_seq_hi_and_reserved}."
    end
    unless clock_seq_low >= 0 && clock_seq_low < 256
      raise ArgumentError,
        "Expected unsigned 8-bit number for clock_seq_low, " +
        "got #{clock_seq_low}."
    end
    unless nodes.respond_to? :size
      raise ArgumentError,
        "Expected nodes to respond to :size."
    end
    unless nodes.size == 6
      raise ArgumentError,
        "Expected nodes to have size of 6."
    end
    for node in nodes
      unless node >= 0 && node < 256
        raise ArgumentError,
          "Expected unsigned 8-bit number for each node, " +
          "got #{node}."
      end
    end
    @time_low = time_low
    @time_mid = time_mid
    @time_hi_and_version = time_hi_and_version
    @clock_seq_hi_and_reserved = clock_seq_hi_and_reserved
    @clock_seq_low = clock_seq_low
    @nodes = nodes
  end

  attr_accessor :time_low
  attr_accessor :time_mid
  attr_accessor :time_hi_and_version
  attr_accessor :clock_seq_hi_and_reserved
  attr_accessor :clock_seq_low
  attr_accessor :nodes

  # Parses a UUID from a string.
  def UUID.parse(uuid_string)
    unless uuid_string.kind_of? String
      raise ArgumentError,
        "Expected String, got #{uuid_string.class.name} instead."
    end
    uuid_components = uuid_string.downcase.scan(
      Regexp.new("^([0-9a-f]{8})-([0-9a-f]{4})-([0-9a-f]{4})-" +
        "([0-9a-f]{2})([0-9a-f]{2})-([0-9a-f]{12})$")).first
    raise ArgumentError, "Invalid UUID format." if uuid_components.nil?
    time_low = uuid_components[0].to_i(16)
    time_mid = uuid_components[1].to_i(16)
    time_hi_and_version = uuid_components[2].to_i(16)
    clock_seq_hi_and_reserved = uuid_components[3].to_i(16)
    clock_seq_low = uuid_components[4].to_i(16)
    nodes = []
    for i in 0..5
      nodes << uuid_components[5][(i * 2)..(i * 2) + 1].to_i(16)
    end
    return UUID.new(time_low, time_mid, time_hi_and_version,
      clock_seq_hi_and_reserved, clock_seq_low, nodes)
  end

  # Parses a UUID from a raw byte string.
  def UUID.parse_raw(raw_string)
    unless raw_string.kind_of? String
      raise ArgumentError,
        "Expected String, got #{raw_string.class.name} instead."
    end
    integer = UUID.convert_byte_string_to_int(raw_string)

    time_low = (integer >> 96) & 0xFFFFFFFF
    time_mid = (integer >> 80) & 0xFFFF
    time_hi_and_version = (integer >> 64) & 0xFFFF
    clock_seq_hi_and_reserved = (integer >> 56) & 0xFF
    clock_seq_low = (integer >> 48) & 0xFF
    nodes = []
    for i in 0..5
      nodes << ((integer >> (40 - (i * 8))) & 0xFF)
    end
    return UUID.new(time_low, time_mid, time_hi_and_version,
      clock_seq_hi_and_reserved, clock_seq_low, nodes)
  end

  # Creates a UUID from a random value.
  def UUID.random_create()
    new_uuid = UUID.parse_raw(UUID.true_random)
    new_uuid.time_hi_and_version &= 0x0FFF
    new_uuid.time_hi_and_version |= (4 << 12)
    new_uuid.clock_seq_hi_and_reserved &= 0x3F
    new_uuid.clock_seq_hi_and_reserved |= 0x80
    return new_uuid
  end

  # Creates a UUID from a timestamp.
  def UUID.timestamp_create(timestamp=nil)
    # We need a lock here to prevent two threads from ever
    # getting the same timestamp.
    @@mutex.synchronize do
      # Always use GMT to generate UUIDs.
      if timestamp.nil?
        gmt_timestamp = Time.now.gmtime
      else
        gmt_timestamp = timestamp.gmtime
      end
      # Convert to 100 nanosecond blocks
      gmt_timestamp_100_nanoseconds = (gmt_timestamp.tv_sec * 10000000) +
        (gmt_timestamp.tv_usec * 10) + 0x01B21DD213814000
      nodes = UUID.get_mac_address.split(":").collect do |octet|
        octet.to_i(16)
      end
      node_id = 0
      for i in 0..5
        node_id += (nodes[i] << (40 - (i * 8)))
      end
      clock_sequence = @@last_clock_sequence
      if clock_sequence.nil?
        clock_sequence = UUID.convert_byte_string_to_int(UUID.true_random)
      end
      if @@last_node_id != nil && @@last_node_id != node_id
        # The node id has changed.  Change the clock id.
        clock_sequence = UUID.convert_byte_string_to_int(UUID.true_random)
      elsif @@last_timestamp != nil &&
          gmt_timestamp_100_nanoseconds <= @@last_timestamp
        clock_sequence = clock_sequence + 1
      end
      @@last_timestamp = gmt_timestamp_100_nanoseconds
      @@last_node_id = node_id
      @@last_clock_sequence = clock_sequence

      time_low = gmt_timestamp_100_nanoseconds & 0xFFFFFFFF
      time_mid = ((gmt_timestamp_100_nanoseconds >> 32) & 0xFFFF)
      time_hi_and_version = ((gmt_timestamp_100_nanoseconds >> 48) & 0x0FFF)
      time_hi_and_version |= (1 << 12)
      clock_seq_low = clock_sequence & 0xFF;
      clock_seq_hi_and_reserved = (clock_sequence & 0x3F00) >> 8
      clock_seq_hi_and_reserved |= 0x80

      return UUID.new(time_low, time_mid, time_hi_and_version,
        clock_seq_hi_and_reserved, clock_seq_low, nodes)
    end
  end

  # Creates a UUID using the MD5 hash.  (Version 3)
  def UUID.md5_create(namespace, name)
    return UUID.create_from_hash(Digest::MD5, namespace, name)
  end

  # Creates a UUID using the SHA1 hash.  (Version 5)
  def UUID.sha1_create(namespace, name)
    return UUID.create_from_hash(Digest::SHA1, namespace, name)
  end

  # This method applies only to version 1 UUIDs.
  # Checks if the node ID was generated from a random number
  # or from an IEEE 802 address (MAC address).
  # Always returns false for UUIDs that aren't version 1.
  # This should not be confused with version 4 UUIDs where
  # more than just the node id is random.
  def random_node_id?
    return false if self.version != 1
    return ((self.nodes.first & 0x01) == 1)
  end

  # Returns true if this UUID is the
  # nil UUID (00000000-0000-0000-0000-000000000000).
  def nil_uuid?
    return false if self.time_low != 0
    return false if self.time_mid != 0
    return false if self.time_hi_and_version != 0
    return false if self.clock_seq_hi_and_reserved != 0
    return false if self.clock_seq_low != 0
    self.nodes.each do |node|
      return false if node != 0
    end
    return true
  end

  # Returns the UUID version type.
  # Possible values:
  # 1 - Time-based with unique or random host identifier
  # 2 - DCE Security version (with POSIX UIDs)
  # 3 - Name-based (MD5 hash)
  # 4 - Random
  # 5 - Name-based (SHA-1 hash)
  def version
    return (time_hi_and_version >> 12)
  end

  # Returns the UUID variant.
  # Possible values:
  # 0b000 - Reserved, NCS backward compatibility.
  # 0b100 - The variant specified in this document.
  # 0b110 - Reserved, Microsoft Corporation backward compatibility.
  # 0b111 - Reserved for future definition.
  def variant
    variant_raw = (clock_seq_hi_and_reserved >> 5)
    result = nil
    if (variant_raw >> 2) == 0
      result = 0x000
    elsif (variant_raw >> 1) == 2
      result = 0x100
    else
      result = variant_raw
    end
    return (result >> 6)
  end

  # Returns true if this UUID is valid.
  def valid?
    if [0b000, 0b100, 0b110, 0b111].include?(self.variant) &&
      (1..5).include?(self.version)
      return true
    else
      return false
    end
  end

  # Returns the IEEE 802 address used to generate this UUID or
  # nil if a MAC address was not used.
  def mac_address
    return nil if self.version != 1
    return nil if self.random_node_id?
    return (self.nodes.collect do |node|
      sprintf("%2.2x", node)
    end).join(":")
  end

  # Returns the timestamp used to generate this UUID
  def timestamp
    return nil if self.version != 1
    gmt_timestamp_100_nanoseconds = 0
    gmt_timestamp_100_nanoseconds +=
      ((self.time_hi_and_version  & 0x0FFF) << 48)
    gmt_timestamp_100_nanoseconds += (self.time_mid << 32)
    gmt_timestamp_100_nanoseconds += self.time_low
    return Time.at(
      (gmt_timestamp_100_nanoseconds - 0x01B21DD213814000) / 10000000.0)
  end

  # Compares two UUIDs lexically
  def <=>(other_uuid)
    check = self.time_low <=> other_uuid.time_low
    return check if check != 0
    check = self.time_mid <=> other_uuid.time_mid
    return check if check != 0
    check = self.time_hi_and_version <=> other_uuid.time_hi_and_version
    return check if check != 0
    check = self.clock_seq_hi_and_reserved <=>
      other_uuid.clock_seq_hi_and_reserved
    return check if check != 0
    check = self.clock_seq_low <=> other_uuid.clock_seq_low
    return check if check != 0
    for i in 0..5
      if (self.nodes[i] < other_uuid.nodes[i])
        return -1
      end
      if (self.nodes[i] > other_uuid.nodes[i])
        return 1
      end
    end
    return 0
  end

  # Returns a representation of the object's state
  def inspect
    return "#<UUID:0x#{self.object_id.to_s(16)} UUID:#{self.to_s}>"
  end

  # Returns the hex digest of the UUID object.
  def hexdigest
    return self.to_i.to_s(16)
  end

  # Returns the raw bytes that represent this UUID.
  def raw
    return UUID.convert_int_to_byte_string(self.to_i, 16)
  end

  # Returns a string representation for this UUID.
  def to_s
    result = sprintf("%8.8x-%4.4x-%4.4x-%2.2x%2.2x-", @time_low, @time_mid,
      @time_hi_and_version, @clock_seq_hi_and_reserved, @clock_seq_low);
    for i in 0..5
      result << sprintf("%2.2x", @nodes[i])
    end
    return result
  end

  # Returns an integer representation for this UUID.
  def to_i
    bytes = (time_low << 96) + (time_mid << 80) +
      (time_hi_and_version << 64) + (clock_seq_hi_and_reserved << 56) +
      (clock_seq_low << 48)
    for i in 0..5
      bytes += (nodes[i] << (40 - (i * 8)))
    end
    return bytes
  end

  # Returns a URI for this UUID.
  def to_uri
    return URI.parse(self.to_uri_string)
  end

  # Returns a URI string for this UUID.
  def to_uri_string
    return "urn:uuid:#{self.to_s}"
  end

  def UUID.create_from_hash(hash_class, namespace, name) #:nodoc:
    if hash_class == Digest::MD5
      version = 3
    elsif hash_class == Digest::SHA1
      version = 5
    else
      raise ArgumentError,
        "Expected Digest::SHA1 or Digest::MD5, got #{hash_class.name}."
    end
    hash = hash_class.new
    hash.update(namespace.raw)
    hash.update(name)
    hash_string = hash.to_s[0..31]
    new_uuid = UUID.parse("#{hash_string[0..7]}-#{hash_string[8..11]}-" +
      "#{hash_string[12..15]}-#{hash_string[16..19]}-#{hash_string[20..31]}")

    new_uuid.time_hi_and_version &= 0x0FFF
    new_uuid.time_hi_and_version |= (version << 12)
    new_uuid.clock_seq_hi_and_reserved &= 0x3F
    new_uuid.clock_seq_hi_and_reserved |= 0x80
    return new_uuid
  end

  # Returns the MAC address of the current computer's network card.
  # Returns nil if a MAC address could not be found.
  def UUID.get_mac_address #:nodoc:
    if @@mac_address.nil?
      if RUBY_PLATFORM =~ /win/ && !(RUBY_PLATFORM =~ /darwin/)
        begin
          ifconfig_output = `ipconfig /all`
          mac_addresses = ifconfig_output.scan(
            Regexp.new("(#{(["[0-9a-fA-F]{2}"] * 6).join("-")})"))
          if mac_addresses.size > 0
            @@mac_address = mac_addresses.first.first.downcase.gsub(/-/, ":")
          end
        rescue
        end
      else
        begin
          mac_addresses = []
          if File.exists?('/sbin/ifconfig')
            ifconfig_output =
              `/sbin/ifconfig 2>&1`
            mac_addresses = ifconfig_output.scan(
              Regexp.new("ether (#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"))
            if mac_addresses.size == 0
              ifconfig_output =
                `/sbin/ifconfig | grep HWaddr | cut -c39- 2>&1`
              mac_addresses = ifconfig_output.scan(
                Regexp.new("(#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"))
            end
          else
            ifconfig_output =
              `ifconfig 2>&1`
            mac_addresses = ifconfig_output.scan(
              Regexp.new("ether (#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"))
            if mac_addresses.size == 0
              ifconfig_output =
                `ifconfig | grep HWaddr | cut -c39- 2>&1`
              mac_addresses = ifconfig_output.scan(
                Regexp.new("(#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"))
            end
          end
          if mac_addresses.size > 0
            @@mac_address = mac_addresses.first.first
          end
        rescue
        end
      end
    end
    return @@mac_address
  end

  # Returns 128 bits of highly unpredictable data.
  # The random number generator isn't perfect, but it's
  # much, much better than the built-in pseudorandom number generators.
  def UUID.true_random #:nodoc:
    require 'benchmark'
    hash = Digest::SHA1.new
    performance = Benchmark.measure do
      hash.update(rand.to_s)
      hash.update(srand.to_s)
      hash.update(rand.to_s)
      hash.update(srand.to_s)
      hash.update(Time.now.to_s)
      hash.update(rand.to_s)
      hash.update(self.object_id.to_s)
      hash.update(rand.to_s)
      hash.update(hash.object_id.to_s)
      hash.update(self.methods.inspect)
      hash.update($:.to_s)
      begin
        random_device = nil
        if File.exists? "/dev/urandom"
          random_device = File.open "/dev/urandom", "r"
        elsif File.exists? "/dev/random"
          random_device = File.open "/dev/random", "r"
        end
        hash.update(random_device.read(20)) if random_device != nil
      rescue
      end
      begin
        srand(hash.to_s.to_i(16) >> 128)
      rescue
      end
      hash.update(rand.to_s)
      hash.update(UUID.true_random) if (rand(2) == 0)
    end
    hash.update(performance.real.to_s)
    hash.update(performance.inspect)
    return UUID.convert_int_to_byte_string(hash.to_s[4..35].to_i(16), 16)
  end

  def UUID.convert_int_to_byte_string(integer, size) #:nodoc:
    byte_string = ""
    for i in 0..(size - 1)
      byte_string << ((integer >> (((size - 1) - i) * 8)) & 0xFF)
    end
    return byte_string
  end

  def UUID.convert_byte_string_to_int(byte_string) #:nodoc:
    integer = 0
    size = byte_string.size
    for i in 0..(size - 1)
      integer += (byte_string[i] << (((size - 1) - i) * 8))
    end
    return integer
  end
end

UUID_DNS_NAMESPACE = UUID.parse("6ba7b810-9dad-11d1-80b4-00c04fd430c8")
UUID_URL_NAMESPACE = UUID.parse("6ba7b811-9dad-11d1-80b4-00c04fd430c8")
UUID_OID_NAMESPACE = UUID.parse("6ba7b812-9dad-11d1-80b4-00c04fd430c8")
UUID_X500_NAMESPACE = UUID.parse("6ba7b814-9dad-11d1-80b4-00c04fd430c8")
	<?php # vim:ts=2:sw=2:noet:
	/* Copyright (c) 2007, OmniTI Computer Consulting, Inc.
	* All Rights Reserved.
	* For licensing information, see:
	* http://labs.omniti.com/alexandria/trunk/LICENSE
	*/

	/**
	* A class for working with RFC 4122 UUIDs
	*/
	class OmniTI_Util_UUID {
	public $binary;

	function __construct($src = null) {
	if ($src !== null) {
	switch (strlen($src)) {
	case 36: /* with -'s */
	$src = str_replace('-', '', $src);
	case 32: /* with -'s stripped */
	$this->binary = pack('H*', $src);
	break;
	case 16: /* binary string */
	$this->binary = $src;
	break;
	case 24: /* base64 encoded binary */
	$this->binary = base64_decode(
	str_replace(
	array('@', '-', '_'),
	array('=', '/', '+'),
	$src));
	break;
	default:
	$this->binary = null;
	}
	} else {
	$this->generate();
	}
	}

	/**
	* returns a 32-bit integer that identifies this host.
	* The node identifier needs to be unique among nodes
	* in a cluster for a given application in order to
	* avoid collisions between generated identifiers.
	* You may extend and override this method if you
	* want to substitute an alternative means of determining
	* the node identifier */
	protected function getNodeId() {
	if (isset($_SERVER['SERVER_ADDR'])) {
	$node = ip2long($_SERVER['SERVER_ADDR']);
	} else {
	/* running from the CLI most likely;
	* inspect the environment to see if we can
	* deduce the hostname, and from there, the
	* IP address */
	static $names = array('HOSTNAME', 'HOST');
	foreach ($names as $name) {
	if (isset($_ENV[$name])) {
	$host = $_ENV[$name];
	} else {
	$host = getenv($name);
	}
	if (strlen($host)) break;
	}
	if (!strlen($host)) {
	// punt
	$node = ip2long('127.0.0.1');
	} else {
	$ip = gethostbyname($host);
	if (strlen($ip)) {
	$node = ip2long($ip);
	} else {
	// punt
	$node = crc32($host);
	}
	}
	}
	return $node;
	}

	/**
	* returns a process identifier.
	* In multi-process servers, this should be the system process ID.
	* In multi-threaded servers, this should be some unique ID to
	* prevent two threads from generating precisely the same UUID
	* at the same time.
	*/
	protected function getLockId() {
	if (function_exists('zend_thread_id')) {
	return zend_thread_id();
	}
	return getmypid();
	}

	/**
	* generate an RFC 4122 UUID.
	* This is psuedo-random UUID influenced by the system clock, IP
	* address and process ID.
	*
	* The intended use is to generate an identifier that can uniquely
	* identify user generated posts, comments etc. made to a website.
	* This generation process should be sufficient to avoid collisions
	* between nodes in a cluster, and between apache children on the
	* same host.
	*
	*/
	function generate() {
	$node = $this->getNodeId();
	$pid = $this->getLockId();

	list($time_mid, $time_lo) = explode(' ', microtime());
	$time_lo = (int)$time_lo;
	$time_mid = (int)substr($time_mid, 2);

	$time_hi = mt_rand(0, 0xfff);
	/* version 4 UUID */
	$time_hi \|= 0x4000;

	$clock_lo = mt_rand(0, 0xff);
	$node_lo = $pid;

	/* type is psuedo-random */
	$clock_hi = mt_rand(0, 0x3f);
	$clock_hi \|= 0x80;

	$this->binary = pack('NnnCCnN',
	$time_lo, $time_mid & 0xffff, $time_hi,
	$clock_hi, $clock_lo, $node_lo, $node);
	}

	/**
	* render the UUID as an RFC4122 standard string representation
	* of the binary bits.
	*/
	function toRFC4122String() {
	$uuid = unpack('Ntl/ntm/nth/Cch/Ccl/nnl/Nn', $this->binary);
	return sprintf("%08x-%04x-%04x-%02x%02x-%04x%08x",
	$uuid['tl'], $uuid['tm'], $uuid['th'],
	$uuid['ch'], $uuid['cl'], $uuid['nl'], $uuid['n']);
	}

	/**
	* render the UUID using a modified base64 representation
	* of the binary bits. This string is shorter than the standard
	* representation, but is not part of any standard specification.
	*/
	function toShortString() {
	return str_replace(
	array('=', '/', '+'),
	array('@', '-', '_'),
	base64_encode($this->binary));
	}
	}

	?>
	#--
	# Copyright (c) 2005 Robert Aman
	#
	# Permission is hereby granted, free of charge, to any person obtaining
	# a copy of this software and associated documentation files (the
	# "Software"), to deal in the Software without restriction, including
	# without limitation the rights to use, copy, modify, merge, publish,
	# distribute, sublicense, and/or sell copies of the Software, and to
	# permit persons to whom the Software is furnished to do so, subject to
	# the following conditions:
	#
	# The above copyright notice and this permission notice shall be
	# included in all copies or substantial portions of the Software.
	#
	# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
	# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
	# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
	# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	#++

	UUID_TOOLS_VERSION = "1.0.0"

	$:.unshift(File.dirname(__FILE__))

	require 'uri'
	require 'time'
	require 'thread'
	require 'digest/sha1'
	require 'digest/md5'

	# Because it's impossible to hype a UUID generator on its genuine merits,
	# I give you... Really bad ASCII art in the comments:
	#
	#
	# \
	# /
	# +
	# ]
	# ]
	# \|
	# /
	# Mp___
	# `~0NNp,
	# __ggM'
	# g0M~"`
	# ]0M*-
	#
	# ___
	# _g000M00g,
	# j0M~ ~M&
	# j0M" ~N,
	# j0P M&
	# jM 1
	# j0 ]1
	# .0P 0,
	# 00' M&
	# 0M ]0L
	# ]0f ___ M0
	# M0NN0M00MMM~"'M 0&
	# `~ ~0 ]0,
	# ]M ]0&
	# M& M0,
	# ____gp_ M& M0_
	# __p0MPM8MM&_ M/ ^0&_
	# gN"` M0N_j0, MM&__
	# _gF `~M0P` __ M00g
	# g0' gM0&, ~M0&
	# _pM` 0, ]M1 "00&
	# _00 /g1MMgj01 ]0MI
	# _0F t"M,7MMM 00I
	# g0' _ N&j& 40'
	# g0' _p0Mq_ ' N0QQNM#g,
	# 0' _g0000000g__ ~M@MMM000g
	# f _jM00@` ~M0000Mgppg, "P00&
	# \| g000~ `~M000000&_ ~0&
	# ]M _M00F "00MM` ~#&
	# `0L m000F #E "0f
	# 9r j000M` 40, 00
	# ]0g_ j00M` ^M0MNggp#gqpg M0&
	# ~MPM0f ~M000000000g_ ,_ygg&M00f
	# `~~~M00000000000000
	# `M0000000000f
	# ~@@@MF~`
	#
	#

	#= uuidtools.rb
	#
	# UUIDTools was designed to be a simple library for generating any
	# of the various types of UUIDs. It conforms to RFC 4122 whenever
	# possible.
	#
	#== Example
	# UUID.md5_create(UUID_DNS_NAMESPACE, "www.widgets.com")
	# => #<UUID:0x287576 UUID:3d813cbb-47fb-32ba-91df-831e1593ac29>
	# UUID.sha1_create(UUID_DNS_NAMESPACE, "www.widgets.com")
	# => #<UUID:0x2a0116 UUID:21f7f8de-8051-5b89-8680-0195ef798b6a>
	# UUID.timestamp_create
	# => #<UUID:0x2adfdc UUID:64a5189c-25b3-11da-a97b-00c04fd430c8>
	# UUID.random_create
	# => #<UUID:0x19013a UUID:984265dc-4200-4f02-ae70-fe4f48964159>
	class UUID
	@@mac_address = nil
	@@last_timestamp = nil
	@@last_node_id = nil
	@@last_clock_sequence = nil
	@@state_file = nil
	@@mutex = Mutex.new

	def initialize(time_low, time_mid, time_hi_and_version,
	clock_seq_hi_and_reserved, clock_seq_low, nodes)
	unless time_low >= 0 && time_low < 4294967296
	raise ArgumentError,
	"Expected unsigned 32-bit number for time_low, got #{time_low}."
	end
	unless time_mid >= 0 && time_mid < 65536
	raise ArgumentError,
	"Expected unsigned 16-bit number for time_mid, got #{time_mid}."
	end
	unless time_hi_and_version >= 0 && time_hi_and_version < 65536
	raise ArgumentError,
	"Expected unsigned 16-bit number for time_hi_and_version, " +
	"got #{time_hi_and_version}."
	end
	unless clock_seq_hi_and_reserved >= 0 && clock_seq_hi_and_reserved < 256
	raise ArgumentError,
	"Expected unsigned 8-bit number for clock_seq_hi_and_reserved, " +
	"got #{clock_seq_hi_and_reserved}."
	end
	unless clock_seq_low >= 0 && clock_seq_low < 256
	raise ArgumentError,
	"Expected unsigned 8-bit number for clock_seq_low, " +
	"got #{clock_seq_low}."
	end
	unless nodes.respond_to? :size
	raise ArgumentError,
	"Expected nodes to respond to :size."
	end
	unless nodes.size == 6
	raise ArgumentError,
	"Expected nodes to have size of 6."
	end
	for node in nodes
	unless node >= 0 && node < 256
	raise ArgumentError,
	"Expected unsigned 8-bit number for each node, " +
	"got #{node}."
	end
	end
	@time_low = time_low
	@time_mid = time_mid
	@time_hi_and_version = time_hi_and_version
	@clock_seq_hi_and_reserved = clock_seq_hi_and_reserved
	@clock_seq_low = clock_seq_low
	@nodes = nodes
	end

	attr_accessor :time_low
	attr_accessor :time_mid
	attr_accessor :time_hi_and_version
	attr_accessor :clock_seq_hi_and_reserved
	attr_accessor :clock_seq_low
	attr_accessor :nodes

	# Parses a UUID from a string.
	def UUID.parse(uuid_string)
	unless uuid_string.kind_of? String
	raise ArgumentError,
	"Expected String, got #{uuid_string.class.name} instead."
	end
	uuid_components = uuid_string.downcase.scan(
	Regexp.new("^([0-9a-f]{8})-([0-9a-f]{4})-([0-9a-f]{4})-" +
	"([0-9a-f]{2})([0-9a-f]{2})-([0-9a-f]{12})$")).first
	raise ArgumentError, "Invalid UUID format." if uuid_components.nil?
	time_low = uuid_components[0].to_i(16)
	time_mid = uuid_components[1].to_i(16)
	time_hi_and_version = uuid_components[2].to_i(16)
	clock_seq_hi_and_reserved = uuid_components[3].to_i(16)
	clock_seq_low = uuid_components[4].to_i(16)
	nodes = []
	for i in 0..5
	nodes << uuid_components[5][(i * 2)..(i * 2) + 1].to_i(16)
	end
	return UUID.new(time_low, time_mid, time_hi_and_version,
	clock_seq_hi_and_reserved, clock_seq_low, nodes)
	end

	# Parses a UUID from a raw byte string.
	def UUID.parse_raw(raw_string)
	unless raw_string.kind_of? String
	raise ArgumentError,
	"Expected String, got #{raw_string.class.name} instead."
	end
	integer = UUID.convert_byte_string_to_int(raw_string)

	time_low = (integer >> 96) & 0xFFFFFFFF
	time_mid = (integer >> 80) & 0xFFFF
	time_hi_and_version = (integer >> 64) & 0xFFFF
	clock_seq_hi_and_reserved = (integer >> 56) & 0xFF
	clock_seq_low = (integer >> 48) & 0xFF
	nodes = []
	for i in 0..5
	nodes << ((integer >> (40 - (i * 8))) & 0xFF)
	end
	return UUID.new(time_low, time_mid, time_hi_and_version,
	clock_seq_hi_and_reserved, clock_seq_low, nodes)
	end

	# Creates a UUID from a random value.
	def UUID.random_create()
	new_uuid = UUID.parse_raw(UUID.true_random)
	new_uuid.time_hi_and_version &= 0x0FFF
	new_uuid.time_hi_and_version \|= (4 << 12)
	new_uuid.clock_seq_hi_and_reserved &= 0x3F
	new_uuid.clock_seq_hi_and_reserved \|= 0x80
	return new_uuid
	end

	# Creates a UUID from a timestamp.
	def UUID.timestamp_create(timestamp=nil)
	# We need a lock here to prevent two threads from ever
	# getting the same timestamp.
	@@mutex.synchronize do
	# Always use GMT to generate UUIDs.
	if timestamp.nil?
	gmt_timestamp = Time.now.gmtime
	else
	gmt_timestamp = timestamp.gmtime
	end
	# Convert to 100 nanosecond blocks
	gmt_timestamp_100_nanoseconds = (gmt_timestamp.tv_sec * 10000000) +
	(gmt_timestamp.tv_usec * 10) + 0x01B21DD213814000
	nodes = UUID.get_mac_address.split(":").collect do \|octet\|
	octet.to_i(16)
	end
	node_id = 0
	for i in 0..5
	node_id += (nodes[i] << (40 - (i * 8)))
	end
	clock_sequence = @@last_clock_sequence
	if clock_sequence.nil?
	clock_sequence = UUID.convert_byte_string_to_int(UUID.true_random)
	end
	if @@last_node_id != nil && @@last_node_id != node_id
	# The node id has changed. Change the clock id.
	clock_sequence = UUID.convert_byte_string_to_int(UUID.true_random)
	elsif @@last_timestamp != nil &&
	gmt_timestamp_100_nanoseconds <= @@last_timestamp
	clock_sequence = clock_sequence + 1
	end
	@@last_timestamp = gmt_timestamp_100_nanoseconds
	@@last_node_id = node_id
	@@last_clock_sequence = clock_sequence

	time_low = gmt_timestamp_100_nanoseconds & 0xFFFFFFFF
	time_mid = ((gmt_timestamp_100_nanoseconds >> 32) & 0xFFFF)
	time_hi_and_version = ((gmt_timestamp_100_nanoseconds >> 48) & 0x0FFF)
	time_hi_and_version \|= (1 << 12)
	clock_seq_low = clock_sequence & 0xFF;
	clock_seq_hi_and_reserved = (clock_sequence & 0x3F00) >> 8
	clock_seq_hi_and_reserved \|= 0x80

	return UUID.new(time_low, time_mid, time_hi_and_version,
	clock_seq_hi_and_reserved, clock_seq_low, nodes)
	end
	end

	# Creates a UUID using the MD5 hash. (Version 3)
	def UUID.md5_create(namespace, name)
	return UUID.create_from_hash(Digest::MD5, namespace, name)
	end

	# Creates a UUID using the SHA1 hash. (Version 5)
	def UUID.sha1_create(namespace, name)
	return UUID.create_from_hash(Digest::SHA1, namespace, name)
	end

	# This method applies only to version 1 UUIDs.
	# Checks if the node ID was generated from a random number
	# or from an IEEE 802 address (MAC address).
	# Always returns false for UUIDs that aren't version 1.
	# This should not be confused with version 4 UUIDs where
	# more than just the node id is random.
	def random_node_id?
	return false if self.version != 1
	return ((self.nodes.first & 0x01) == 1)
	end

	# Returns true if this UUID is the
	# nil UUID (00000000-0000-0000-0000-000000000000).
	def nil_uuid?
	return false if self.time_low != 0
	return false if self.time_mid != 0
	return false if self.time_hi_and_version != 0
	return false if self.clock_seq_hi_and_reserved != 0
	return false if self.clock_seq_low != 0
	self.nodes.each do \|node\|
	return false if node != 0
	end
	return true
	end

	# Returns the UUID version type.
	# Possible values:
	# 1 - Time-based with unique or random host identifier
	# 2 - DCE Security version (with POSIX UIDs)
	# 3 - Name-based (MD5 hash)
	# 4 - Random
	# 5 - Name-based (SHA-1 hash)
	def version
	return (time_hi_and_version >> 12)
	end

	# Returns the UUID variant.
	# Possible values:
	# 0b000 - Reserved, NCS backward compatibility.
	# 0b100 - The variant specified in this document.
	# 0b110 - Reserved, Microsoft Corporation backward compatibility.
	# 0b111 - Reserved for future definition.
	def variant
	variant_raw = (clock_seq_hi_and_reserved >> 5)
	result = nil
	if (variant_raw >> 2) == 0
	result = 0x000
	elsif (variant_raw >> 1) == 2
	result = 0x100
	else
	result = variant_raw
	end
	return (result >> 6)
	end

	# Returns true if this UUID is valid.
	def valid?
	if [0b000, 0b100, 0b110, 0b111].include?(self.variant) &&
	(1..5).include?(self.version)
	return true
	else
	return false
	end
	end

	# Returns the IEEE 802 address used to generate this UUID or
	# nil if a MAC address was not used.
	def mac_address
	return nil if self.version != 1
	return nil if self.random_node_id?
	return (self.nodes.collect do \|node\|
	sprintf("%2.2x", node)
	end).join(":")
	end

	# Returns the timestamp used to generate this UUID
	def timestamp
	return nil if self.version != 1
	gmt_timestamp_100_nanoseconds = 0
	gmt_timestamp_100_nanoseconds +=
	((self.time_hi_and_version & 0x0FFF) << 48)
	gmt_timestamp_100_nanoseconds += (self.time_mid << 32)
	gmt_timestamp_100_nanoseconds += self.time_low
	return Time.at(
	(gmt_timestamp_100_nanoseconds - 0x01B21DD213814000) / 10000000.0)
	end

	# Compares two UUIDs lexically
	def <=>(other_uuid)
	check = self.time_low <=> other_uuid.time_low
	return check if check != 0
	check = self.time_mid <=> other_uuid.time_mid
	return check if check != 0
	check = self.time_hi_and_version <=> other_uuid.time_hi_and_version
	return check if check != 0
	check = self.clock_seq_hi_and_reserved <=>
	other_uuid.clock_seq_hi_and_reserved
	return check if check != 0
	check = self.clock_seq_low <=> other_uuid.clock_seq_low
	return check if check != 0
	for i in 0..5
	if (self.nodes[i] < other_uuid.nodes[i])
	return -1
	end
	if (self.nodes[i] > other_uuid.nodes[i])
	return 1
	end
	end
	return 0
	end

	# Returns a representation of the object's state
	def inspect
	return "#<UUID:0x#{self.object_id.to_s(16)} UUID:#{self.to_s}>"
	end

	# Returns the hex digest of the UUID object.
	def hexdigest
	return self.to_i.to_s(16)
	end

	# Returns the raw bytes that represent this UUID.
	def raw
	return UUID.convert_int_to_byte_string(self.to_i, 16)
	end

	# Returns a string representation for this UUID.
	def to_s
	result = sprintf("%8.8x-%4.4x-%4.4x-%2.2x%2.2x-", @time_low, @time_mid,
	@time_hi_and_version, @clock_seq_hi_and_reserved, @clock_seq_low);
	for i in 0..5
	result << sprintf("%2.2x", @nodes[i])
	end
	return result
	end

	# Returns an integer representation for this UUID.
	def to_i
	bytes = (time_low << 96) + (time_mid << 80) +
	(time_hi_and_version << 64) + (clock_seq_hi_and_reserved << 56) +
	(clock_seq_low << 48)
	for i in 0..5
	bytes += (nodes[i] << (40 - (i * 8)))
	end
	return bytes
	end

	# Returns a URI for this UUID.
	def to_uri
	return URI.parse(self.to_uri_string)
	end

	# Returns a URI string for this UUID.
	def to_uri_string
	return "urn:uuid:#{self.to_s}"
	end

	def UUID.create_from_hash(hash_class, namespace, name) #:nodoc:
	if hash_class == Digest::MD5
	version = 3
	elsif hash_class == Digest::SHA1
	version = 5
	else
	raise ArgumentError,
	"Expected Digest::SHA1 or Digest::MD5, got #{hash_class.name}."
	end
	hash = hash_class.new
	hash.update(namespace.raw)
	hash.update(name)
	hash_string = hash.to_s[0..31]
	new_uuid = UUID.parse("#{hash_string[0..7]}-#{hash_string[8..11]}-" +
	"#{hash_string[12..15]}-#{hash_string[16..19]}-#{hash_string[20..31]}")

	new_uuid.time_hi_and_version &= 0x0FFF
	new_uuid.time_hi_and_version \|= (version << 12)
	new_uuid.clock_seq_hi_and_reserved &= 0x3F
	new_uuid.clock_seq_hi_and_reserved \|= 0x80
	return new_uuid
	end

	# Returns the MAC address of the current computer's network card.
	# Returns nil if a MAC address could not be found.
	def UUID.get_mac_address #:nodoc:
	if @@mac_address.nil?
	if RUBY_PLATFORM =~ /win/ && !(RUBY_PLATFORM =~ /darwin/)
	begin
	ifconfig_output = `ipconfig /all`
	mac_addresses = ifconfig_output.scan(
	Regexp.new("(#{(["[0-9a-fA-F]{2}"] * 6).join("-")})"))
	if mac_addresses.size > 0
	@@mac_address = mac_addresses.first.first.downcase.gsub(/-/, ":")
	end
	rescue
	end
	else
	begin
	mac_addresses = []
	if File.exists?('/sbin/ifconfig')
	ifconfig_output =
	`/sbin/ifconfig 2>&1`
	mac_addresses = ifconfig_output.scan(
	Regexp.new("ether (#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"))
	if mac_addresses.size == 0
	ifconfig_output =
	`/sbin/ifconfig \| grep HWaddr \| cut -c39- 2>&1`
	mac_addresses = ifconfig_output.scan(
	Regexp.new("(#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"))
	end
	else
	ifconfig_output =
	`ifconfig 2>&1`
	mac_addresses = ifconfig_output.scan(
	Regexp.new("ether (#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"))
	if mac_addresses.size == 0
	ifconfig_output =
	`ifconfig \| grep HWaddr \| cut -c39- 2>&1`
	mac_addresses = ifconfig_output.scan(
	Regexp.new("(#{(["[0-9a-fA-F]{2}"] * 6).join(":")})"))
	end
	end
	if mac_addresses.size > 0
	@@mac_address = mac_addresses.first.first
	end
	rescue
	end
	end
	end
	return @@mac_address
	end

	# Returns 128 bits of highly unpredictable data.
	# The random number generator isn't perfect, but it's
	# much, much better than the built-in pseudorandom number generators.
	def UUID.true_random #:nodoc:
	require 'benchmark'
	hash = Digest::SHA1.new
	performance = Benchmark.measure do
	hash.update(rand.to_s)
	hash.update(srand.to_s)
	hash.update(rand.to_s)
	hash.update(srand.to_s)
	hash.update(Time.now.to_s)
	hash.update(rand.to_s)
	hash.update(self.object_id.to_s)
	hash.update(rand.to_s)
	hash.update(hash.object_id.to_s)
	hash.update(self.methods.inspect)
	hash.update($:.to_s)
	begin
	random_device = nil
	if File.exists? "/dev/urandom"
	random_device = File.open "/dev/urandom", "r"
	elsif File.exists? "/dev/random"
	random_device = File.open "/dev/random", "r"
	end
	hash.update(random_device.read(20)) if random_device != nil
	rescue
	end
	begin
	srand(hash.to_s.to_i(16) >> 128)
	rescue
	end
	hash.update(rand.to_s)
	hash.update(UUID.true_random) if (rand(2) == 0)
	end
	hash.update(performance.real.to_s)
	hash.update(performance.inspect)
	return UUID.convert_int_to_byte_string(hash.to_s[4..35].to_i(16), 16)
	end

	def UUID.convert_int_to_byte_string(integer, size) #:nodoc:
	byte_string = ""
	for i in 0..(size - 1)
	byte_string << ((integer >> (((size - 1) - i) * 8)) & 0xFF)
	end
	return byte_string
	end

	def UUID.convert_byte_string_to_int(byte_string) #:nodoc:
	integer = 0
	size = byte_string.size
	for i in 0..(size - 1)
	integer += (byte_string[i] << (((size - 1) - i) * 8))
	end
	return integer
	end
	end

	UUID_DNS_NAMESPACE = UUID.parse("6ba7b810-9dad-11d1-80b4-00c04fd430c8")
	UUID_URL_NAMESPACE = UUID.parse("6ba7b811-9dad-11d1-80b4-00c04fd430c8")
	UUID_OID_NAMESPACE = UUID.parse("6ba7b812-9dad-11d1-80b4-00c04fd430c8")
	UUID_X500_NAMESPACE = UUID.parse("6ba7b814-9dad-11d1-80b4-00c04fd430c8")