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Diffstat (limited to 'ruby_1_8_6/lib/rinda/rinda.rb')
| -rw-r--r-- | ruby_1_8_6/lib/rinda/rinda.rb | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/ruby_1_8_6/lib/rinda/rinda.rb b/ruby_1_8_6/lib/rinda/rinda.rb new file mode 100644 index 0000000000..6c59e68654 --- /dev/null +++ b/ruby_1_8_6/lib/rinda/rinda.rb @@ -0,0 +1,283 @@ +require 'drb/drb' +require 'thread' + +## +# A module to implement the Linda distributed computing paradigm in Ruby. +# +# Rinda is part of DRb (dRuby). +# +# == Example(s) +# +# See the sample/drb/ directory in the Ruby distribution, from 1.8.2 onwards. +# +#-- +# TODO +# == Introduction to Linda/rinda? +# +# == Why is this library separate from DRb? + +module Rinda + + ## + # Rinda error base class + + class RindaError < RuntimeError; end + + ## + # Raised when a hash-based tuple has an invalid key. + + class InvalidHashTupleKey < RindaError; end + + ## + # Raised when trying to use a canceled tuple. + + class RequestCanceledError < ThreadError; end + + ## + # Raised when trying to use an expired tuple. + + class RequestExpiredError < ThreadError; end + + ## + # A tuple is the elementary object in Rinda programming. + # Tuples may be matched against templates if the tuple and + # the template are the same size. + + class Tuple + + ## + # Creates a new Tuple from +ary_or_hash+ which must be an Array or Hash. + + def initialize(ary_or_hash) + if hash?(ary_or_hash) + init_with_hash(ary_or_hash) + else + init_with_ary(ary_or_hash) + end + end + + ## + # The number of elements in the tuple. + + def size + @tuple.size + end + + ## + # Accessor method for elements of the tuple. + + def [](k) + @tuple[k] + end + + ## + # Fetches item +k+ from the tuple. + + def fetch(k) + @tuple.fetch(k) + end + + ## + # Iterate through the tuple, yielding the index or key, and the + # value, thus ensuring arrays are iterated similarly to hashes. + + def each # FIXME + if Hash === @tuple + @tuple.each { |k, v| yield(k, v) } + else + @tuple.each_with_index { |v, k| yield(k, v) } + end + end + + ## + # Return the tuple itself + def value + @tuple + end + + private + + def hash?(ary_or_hash) + ary_or_hash.respond_to?(:keys) + end + + ## + # Munges +ary+ into a valid Tuple. + + def init_with_ary(ary) + @tuple = Array.new(ary.size) + @tuple.size.times do |i| + @tuple[i] = ary[i] + end + end + + ## + # Ensures +hash+ is a valid Tuple. + + def init_with_hash(hash) + @tuple = Hash.new + hash.each do |k, v| + raise InvalidHashTupleKey unless String === k + @tuple[k] = v + end + end + + end + + ## + # Templates are used to match tuples in Rinda. + + class Template < Tuple + + ## + # Matches this template against +tuple+. The +tuple+ must be the same + # size as the template. An element with a +nil+ value in a template acts + # as a wildcard, matching any value in the corresponding position in the + # tuple. Elements of the template match the +tuple+ if the are #== or + # #===. + # + # Template.new([:foo, 5]).match Tuple.new([:foo, 5]) # => true + # Template.new([:foo, nil]).match Tuple.new([:foo, 5]) # => true + # Template.new([String]).match Tuple.new(['hello']) # => true + # + # Template.new([:foo]).match Tuple.new([:foo, 5]) # => false + # Template.new([:foo, 6]).match Tuple.new([:foo, 5]) # => false + # Template.new([:foo, nil]).match Tuple.new([:foo]) # => false + # Template.new([:foo, 6]).match Tuple.new([:foo]) # => false + + def match(tuple) + return false unless tuple.respond_to?(:size) + return false unless tuple.respond_to?(:fetch) + return false unless self.size == tuple.size + each do |k, v| + begin + it = tuple.fetch(k) + rescue + return false + end + next if v.nil? + next if v == it + next if v === it + return false + end + return true + end + + ## + # Alias for #match. + + def ===(tuple) + match(tuple) + end + + end + + ## + # <i>Documentation?</i> + + class DRbObjectTemplate + + ## + # Creates a new DRbObjectTemplate that will match against +uri+ and +ref+. + + def initialize(uri=nil, ref=nil) + @drb_uri = uri + @drb_ref = ref + end + + ## + # This DRbObjectTemplate matches +ro+ if the remote object's drburi and + # drbref are the same. +nil+ is used as a wildcard. + + def ===(ro) + return true if super(ro) + unless @drb_uri.nil? + return false unless (@drb_uri === ro.__drburi rescue false) + end + unless @drb_ref.nil? + return false unless (@drb_ref === ro.__drbref rescue false) + end + true + end + + end + + ## + # TupleSpaceProxy allows a remote Tuplespace to appear as local. + + class TupleSpaceProxy + + ## + # Creates a new TupleSpaceProxy to wrap +ts+. + + def initialize(ts) + @ts = ts + end + + ## + # Adds +tuple+ to the proxied TupleSpace. See TupleSpace#write. + + def write(tuple, sec=nil) + @ts.write(tuple, sec) + end + + ## + # Takes +tuple+ from the proxied TupleSpace. See TupleSpace#take. + + def take(tuple, sec=nil, &block) + port = [] + @ts.move(DRbObject.new(port), tuple, sec, &block) + port[0] + end + + ## + # Reads +tuple+ from the proxied TupleSpace. See TupleSpace#read. + + def read(tuple, sec=nil, &block) + @ts.read(tuple, sec, &block) + end + + ## + # Reads all tuples matching +tuple+ from the proxied TupleSpace. See + # TupleSpace#read_all. + + def read_all(tuple) + @ts.read_all(tuple) + end + + ## + # Registers for notifications of event +ev+ on the proxied TupleSpace. + # See TupleSpace#notify + + def notify(ev, tuple, sec=nil) + @ts.notify(ev, tuple, sec) + end + + end + + ## + # An SimpleRenewer allows a TupleSpace to check if a TupleEntry is still + # alive. + + class SimpleRenewer + + include DRbUndumped + + ## + # Creates a new SimpleRenewer that keeps an object alive for another +sec+ + # seconds. + + def initialize(sec=180) + @sec = sec + end + + ## + # Called by the TupleSpace to check if the object is still alive. + + def renew + @sec + end + end + +end + |