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bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/atomic_boolean.rb

@@ -0,0 +1,127 @@
+require 'concurrent/utility/native_extension_loader' # load native parts first
+
+require 'concurrent/atomic/mutex_atomic_boolean'
+
+module Concurrent
+
+  ###################################################################
+
+  # @!macro atomic_boolean_method_initialize
+  #
+  #   Creates a new `AtomicBoolean` with the given initial value.
+  #
+  #   @param [Boolean] initial the initial value
+
+  # @!macro atomic_boolean_method_value_get
+  #
+  #   Retrieves the current `Boolean` value.
+  #
+  #   @return [Boolean] the current value
+
+  # @!macro atomic_boolean_method_value_set
+  #
+  #   Explicitly sets the value.
+  #
+  #   @param [Boolean] value the new value to be set
+  #
+  #   @return [Boolean] the current value
+
+  # @!macro atomic_boolean_method_true_question
+  #
+  #   Is the current value `true`
+  #
+  #   @return [Boolean] true if the current value is `true`, else false
+
+  # @!macro atomic_boolean_method_false_question
+  #
+  #   Is the current value `false`
+  #
+  #   @return [Boolean] true if the current value is `false`, else false
+
+  # @!macro atomic_boolean_method_make_true
+  #
+  #   Explicitly sets the value to true.
+  #
+  #   @return [Boolean] true if value has changed, otherwise false
+
+  # @!macro atomic_boolean_method_make_false
+  #
+  #   Explicitly sets the value to false.
+  #
+  #   @return [Boolean] true if value has changed, otherwise false
+
+  ###################################################################
+
+  # @!macro atomic_boolean_public_api
+  #
+  #   @!method initialize(initial = false)
+  #     @!macro  atomic_boolean_method_initialize
+  #
+  #   @!method value
+  #     @!macro  atomic_boolean_method_value_get
+  #
+  #   @!method value=(value)
+  #     @!macro  atomic_boolean_method_value_set
+  #
+  #   @!method true?
+  #     @!macro  atomic_boolean_method_true_question
+  #
+  #   @!method false?
+  #     @!macro  atomic_boolean_method_false_question
+  #
+  #   @!method make_true
+  #     @!macro  atomic_boolean_method_make_true
+  #
+  #   @!method make_false
+  #     @!macro  atomic_boolean_method_make_false
+
+  ###################################################################
+
+  # @!visibility private
+  # @!macro internal_implementation_note
+  AtomicBooleanImplementation = case
+                                when Concurrent.on_cruby? && Concurrent.c_extensions_loaded?
+                                  CAtomicBoolean
+                                when Concurrent.on_jruby?
+                                  JavaAtomicBoolean
+                                else
+                                  MutexAtomicBoolean
+                                end
+  private_constant :AtomicBooleanImplementation
+
+  # @!macro atomic_boolean
+  #
+  #   A boolean value that can be updated atomically. Reads and writes to an atomic
+  #   boolean and thread-safe and guaranteed to succeed. Reads and writes may block
+  #   briefly but no explicit locking is required.
+  #
+  #   @!macro thread_safe_variable_comparison
+  #
+  #   Performance:
+  #
+  #   ```
+  #   Testing with ruby 2.1.2
+  #   Testing with Concurrent::MutexAtomicBoolean...
+  #     2.790000   0.000000   2.790000 (  2.791454)
+  #   Testing with Concurrent::CAtomicBoolean...
+  #     0.740000   0.000000   0.740000 (  0.740206)
+  #
+  #   Testing with jruby 1.9.3
+  #   Testing with Concurrent::MutexAtomicBoolean...
+  #     5.240000   2.520000   7.760000 (  3.683000)
+  #   Testing with Concurrent::JavaAtomicBoolean...
+  #     3.340000   0.010000   3.350000 (  0.855000)
+  #   ```
+  #
+  #   @see http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/atomic/AtomicBoolean.html java.util.concurrent.atomic.AtomicBoolean
+  #
+  # @!macro atomic_boolean_public_api
+  class AtomicBoolean < AtomicBooleanImplementation
+    # @return [String] Short string representation.
+    def to_s
+      format '%s value:%s>', super[0..-2], value
+    end
+
+    alias_method :inspect, :to_s
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/atomic_fixnum.rb

@@ -0,0 +1,144 @@
+require 'concurrent/utility/native_extension_loader' # load native parts first
+
+require 'concurrent/atomic/mutex_atomic_fixnum'
+
+module Concurrent
+
+  ###################################################################
+
+  # @!macro atomic_fixnum_method_initialize
+  #
+  #   Creates a new `AtomicFixnum` with the given initial value.
+  #
+  #   @param [Fixnum] initial the initial value
+  #   @raise [ArgumentError] if the initial value is not a `Fixnum`
+
+  # @!macro atomic_fixnum_method_value_get
+  #
+  #   Retrieves the current `Fixnum` value.
+  #
+  #   @return [Fixnum] the current value
+
+  # @!macro atomic_fixnum_method_value_set
+  #
+  #   Explicitly sets the value.
+  #
+  #   @param [Fixnum] value the new value to be set
+  #
+  #   @return [Fixnum] the current value
+  #
+  #   @raise [ArgumentError] if the new value is not a `Fixnum`
+
+  # @!macro atomic_fixnum_method_increment
+  #
+  #   Increases the current value by the given amount (defaults to 1).
+  #
+  #   @param [Fixnum] delta the amount by which to increase the current value
+  #
+  #   @return [Fixnum] the current value after incrementation
+
+  # @!macro atomic_fixnum_method_decrement
+  #
+  #   Decreases the current value by the given amount (defaults to 1).
+  #
+  #   @param [Fixnum] delta the amount by which to decrease the current value
+  #
+  #   @return [Fixnum] the current value after decrementation
+
+  # @!macro atomic_fixnum_method_compare_and_set
+  #
+  #   Atomically sets the value to the given updated value if the current
+  #   value == the expected value.
+  #
+  #   @param [Fixnum] expect the expected value
+  #   @param [Fixnum] update the new value
+  #
+  #   @return [Boolean] true if the value was updated else false
+
+  # @!macro atomic_fixnum_method_update
+  #
+  #   Pass the current value to the given block, replacing it
+  #   with the block's result. May retry if the value changes
+  #   during the block's execution.
+  #
+  #   @yield [Object] Calculate a new value for the atomic reference using
+  #     given (old) value
+  #   @yieldparam [Object] old_value the starting value of the atomic reference
+  #
+  #   @return [Object] the new value
+
+  ###################################################################
+
+  # @!macro atomic_fixnum_public_api
+  #
+  #   @!method initialize(initial = 0)
+  #     @!macro atomic_fixnum_method_initialize
+  #
+  #   @!method value
+  #     @!macro atomic_fixnum_method_value_get
+  #
+  #   @!method value=(value)
+  #     @!macro atomic_fixnum_method_value_set
+  #
+  #   @!method increment(delta = 1)
+  #     @!macro atomic_fixnum_method_increment
+  #
+  #   @!method decrement(delta = 1)
+  #     @!macro atomic_fixnum_method_decrement
+  #
+  #   @!method compare_and_set(expect, update)
+  #     @!macro atomic_fixnum_method_compare_and_set
+  #
+  #   @!method update
+  #     @!macro atomic_fixnum_method_update
+
+  ###################################################################
+
+  # @!visibility private
+  # @!macro internal_implementation_note
+  AtomicFixnumImplementation = case
+                               when Concurrent.on_cruby? && Concurrent.c_extensions_loaded?
+                                 CAtomicFixnum
+                               when Concurrent.on_jruby?
+                                 JavaAtomicFixnum
+                               else
+                                 MutexAtomicFixnum
+                               end
+  private_constant :AtomicFixnumImplementation
+
+  # @!macro atomic_fixnum
+  #
+  #   A numeric value that can be updated atomically. Reads and writes to an atomic
+  #   fixnum and thread-safe and guaranteed to succeed. Reads and writes may block
+  #   briefly but no explicit locking is required.
+  #
+  #   @!macro thread_safe_variable_comparison
+  #
+  #   Performance:
+  #
+  #   ```
+  #   Testing with ruby 2.1.2
+  #   Testing with Concurrent::MutexAtomicFixnum...
+  #     3.130000   0.000000   3.130000 (  3.136505)
+  #   Testing with Concurrent::CAtomicFixnum...
+  #     0.790000   0.000000   0.790000 (  0.785550)
+  #
+  #   Testing with jruby 1.9.3
+  #   Testing with Concurrent::MutexAtomicFixnum...
+  #     5.460000   2.460000   7.920000 (  3.715000)
+  #   Testing with Concurrent::JavaAtomicFixnum...
+  #     4.520000   0.030000   4.550000 (  1.187000)
+  #   ```
+  #
+  #   @see http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/atomic/AtomicLong.html java.util.concurrent.atomic.AtomicLong
+  #
+  # @!macro atomic_fixnum_public_api
+  class AtomicFixnum < AtomicFixnumImplementation
+    # @return [String] Short string representation.
+    def to_s
+      format '%s value:%s>', super[0..-2], value
+    end
+
+    alias_method :inspect, :to_s
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/atomic_markable_reference.rb

@@ -0,0 +1,167 @@
+require 'concurrent/errors'
+require 'concurrent/synchronization/object'
+
+module Concurrent
+  # An atomic reference which maintains an object reference along with a mark bit
+  # that can be updated atomically.
+  #
+  # @see http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/atomic/AtomicMarkableReference.html
+  #   java.util.concurrent.atomic.AtomicMarkableReference
+  class AtomicMarkableReference < ::Concurrent::Synchronization::Object
+
+    attr_atomic(:reference)
+    private :reference, :reference=, :swap_reference, :compare_and_set_reference, :update_reference
+
+    def initialize(value = nil, mark = false)
+      super()
+      self.reference = immutable_array(value, mark)
+    end
+
+    # Atomically sets the value and mark to the given updated value and
+    # mark given both:
+    #   - the current value == the expected value &&
+    #   - the current mark == the expected mark
+    #
+    # @param [Object] expected_val the expected value
+    # @param [Object] new_val the new value
+    # @param [Boolean] expected_mark the expected mark
+    # @param [Boolean] new_mark the new mark
+    #
+    # @return [Boolean] `true` if successful. A `false` return indicates
+    # that the actual value was not equal to the expected value or the
+    # actual mark was not equal to the expected mark
+    def compare_and_set(expected_val, new_val, expected_mark, new_mark)
+      # Memoize a valid reference to the current AtomicReference for
+      # later comparison.
+      current             = reference
+      curr_val, curr_mark = current
+
+      # Ensure that that the expected marks match.
+      return false unless expected_mark == curr_mark
+
+      if expected_val.is_a? Numeric
+        # If the object is a numeric, we need to ensure we are comparing
+        # the numerical values
+        return false unless expected_val == curr_val
+      else
+        # Otherwise, we need to ensure we are comparing the object identity.
+        # Theoretically, this could be incorrect if a user monkey-patched
+        # `Object#equal?`, but they should know that they are playing with
+        # fire at that point.
+        return false unless expected_val.equal? curr_val
+      end
+
+      prospect = immutable_array(new_val, new_mark)
+
+      compare_and_set_reference current, prospect
+    end
+
+    alias_method :compare_and_swap, :compare_and_set
+
+    # Gets the current reference and marked values.
+    #
+    # @return [Array] the current reference and marked values
+    def get
+      reference
+    end
+
+    # Gets the current value of the reference
+    #
+    # @return [Object] the current value of the reference
+    def value
+      reference[0]
+    end
+
+    # Gets the current marked value
+    #
+    # @return [Boolean] the current marked value
+    def mark
+      reference[1]
+    end
+
+    alias_method :marked?, :mark
+
+    # _Unconditionally_ sets to the given value of both the reference and
+    # the mark.
+    #
+    # @param [Object] new_val the new value
+    # @param [Boolean] new_mark the new mark
+    #
+    # @return [Array] both the new value and the new mark
+    def set(new_val, new_mark)
+      self.reference = immutable_array(new_val, new_mark)
+    end
+
+    # Pass the current value and marked state to the given block, replacing it
+    # with the block's results. May retry if the value changes during the
+    # block's execution.
+    #
+    # @yield [Object] Calculate a new value and marked state for the atomic
+    #   reference using given (old) value and (old) marked
+    # @yieldparam [Object] old_val the starting value of the atomic reference
+    # @yieldparam [Boolean] old_mark the starting state of marked
+    #
+    # @return [Array] the new value and new mark
+    def update
+      loop do
+        old_val, old_mark = reference
+        new_val, new_mark = yield old_val, old_mark
+
+        if compare_and_set old_val, new_val, old_mark, new_mark
+          return immutable_array(new_val, new_mark)
+        end
+      end
+    end
+
+    # Pass the current value to the given block, replacing it
+    # with the block's result. Raise an exception if the update
+    # fails.
+    #
+    # @yield [Object] Calculate a new value and marked state for the atomic
+    #   reference using given (old) value and (old) marked
+    # @yieldparam [Object] old_val the starting value of the atomic reference
+    # @yieldparam [Boolean] old_mark the starting state of marked
+    #
+    # @return [Array] the new value and marked state
+    #
+    # @raise [Concurrent::ConcurrentUpdateError] if the update fails
+    def try_update!
+      old_val, old_mark = reference
+      new_val, new_mark = yield old_val, old_mark
+
+      unless compare_and_set old_val, new_val, old_mark, new_mark
+        fail ::Concurrent::ConcurrentUpdateError,
+             'AtomicMarkableReference: Update failed due to race condition.',
+             'Note: If you would like to guarantee an update, please use ' +
+                 'the `AtomicMarkableReference#update` method.'
+      end
+
+      immutable_array(new_val, new_mark)
+    end
+
+    # Pass the current value to the given block, replacing it with the
+    # block's result. Simply return nil if update fails.
+    #
+    # @yield [Object] Calculate a new value and marked state for the atomic
+    #   reference using given (old) value and (old) marked
+    # @yieldparam [Object] old_val the starting value of the atomic reference
+    # @yieldparam [Boolean] old_mark the starting state of marked
+    #
+    # @return [Array] the new value and marked state, or nil if
+    # the update failed
+    def try_update
+      old_val, old_mark = reference
+      new_val, new_mark = yield old_val, old_mark
+
+      return unless compare_and_set old_val, new_val, old_mark, new_mark
+
+      immutable_array(new_val, new_mark)
+    end
+
+    private
+
+    def immutable_array(*args)
+      args.freeze
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/atomic_reference.rb

@@ -0,0 +1,135 @@
+require 'concurrent/utility/native_extension_loader' # load native parts first
+
+require 'concurrent/atomic_reference/atomic_direct_update'
+require 'concurrent/atomic_reference/numeric_cas_wrapper'
+require 'concurrent/atomic_reference/mutex_atomic'
+
+# Shim for TruffleRuby::AtomicReference
+if Concurrent.on_truffleruby? && !defined?(TruffleRuby::AtomicReference)
+  # @!visibility private
+  module TruffleRuby
+    AtomicReference = Truffle::AtomicReference
+  end
+end
+
+module Concurrent
+
+  # @!macro internal_implementation_note
+  AtomicReferenceImplementation = case
+                                  when Concurrent.on_cruby? && Concurrent.c_extensions_loaded?
+                                    # @!visibility private
+                                    # @!macro internal_implementation_note
+                                    class CAtomicReference
+                                      include AtomicDirectUpdate
+                                      include AtomicNumericCompareAndSetWrapper
+                                      alias_method :compare_and_swap, :compare_and_set
+                                    end
+                                    CAtomicReference
+                                  when Concurrent.on_jruby?
+                                    # @!visibility private
+                                    # @!macro internal_implementation_note
+                                    class JavaAtomicReference
+                                      include AtomicDirectUpdate
+                                    end
+                                    JavaAtomicReference
+                                  when Concurrent.on_truffleruby?
+                                    class TruffleRubyAtomicReference < TruffleRuby::AtomicReference
+                                      include AtomicDirectUpdate
+                                      alias_method :value, :get
+                                      alias_method :value=, :set
+                                      alias_method :compare_and_swap, :compare_and_set
+                                      alias_method :swap, :get_and_set
+                                    end
+                                    TruffleRubyAtomicReference
+                                  else
+                                    MutexAtomicReference
+                                  end
+  private_constant :AtomicReferenceImplementation
+
+  # An object reference that may be updated atomically. All read and write
+  # operations have java volatile semantic.
+  #
+  # @!macro thread_safe_variable_comparison
+  #
+  # @see http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/atomic/AtomicReference.html
+  # @see http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/atomic/package-summary.html
+  #
+  # @!method initialize(value = nil)
+  #   @!macro atomic_reference_method_initialize
+  #     @param [Object] value The initial value.
+  #
+  # @!method get
+  #   @!macro atomic_reference_method_get
+  #     Gets the current value.
+  #     @return [Object] the current value
+  #
+  # @!method set(new_value)
+  #   @!macro atomic_reference_method_set
+  #     Sets to the given value.
+  #     @param [Object] new_value the new value
+  #     @return [Object] the new value
+  #
+  # @!method get_and_set(new_value)
+  #   @!macro atomic_reference_method_get_and_set
+  #     Atomically sets to the given value and returns the old value.
+  #     @param [Object] new_value the new value
+  #     @return [Object] the old value
+  #
+  # @!method compare_and_set(old_value, new_value)
+  #   @!macro atomic_reference_method_compare_and_set
+  #
+  #     Atomically sets the value to the given updated value if
+  #     the current value == the expected value.
+  #
+  #     @param [Object] old_value the expected value
+  #     @param [Object] new_value the new value
+  #
+  #     @return [Boolean] `true` if successful. A `false` return indicates
+  #     that the actual value was not equal to the expected value.
+  #
+  # @!method update
+  #   Pass the current value to the given block, replacing it
+  #   with the block's result. May retry if the value changes
+  #   during the block's execution.
+  #
+  #   @yield [Object] Calculate a new value for the atomic reference using
+  #     given (old) value
+  #   @yieldparam [Object] old_value the starting value of the atomic reference
+  #   @return [Object] the new value
+  #
+  # @!method try_update
+  #   Pass the current value to the given block, replacing it
+  #   with the block's result. Return nil if the update fails.
+  #
+  #   @yield [Object] Calculate a new value for the atomic reference using
+  #     given (old) value
+  #   @yieldparam [Object] old_value the starting value of the atomic reference
+  #   @note This method was altered to avoid raising an exception by default.
+  #     Instead, this method now returns `nil` in case of failure. For more info,
+  #     please see: https://github.com/ruby-concurrency/concurrent-ruby/pull/336
+  #   @return [Object] the new value, or nil if update failed
+  #
+  # @!method try_update!
+  #   Pass the current value to the given block, replacing it
+  #   with the block's result. Raise an exception if the update
+  #   fails.
+  #
+  #   @yield [Object] Calculate a new value for the atomic reference using
+  #     given (old) value
+  #   @yieldparam [Object] old_value the starting value of the atomic reference
+  #   @note This behavior mimics the behavior of the original
+  #     `AtomicReference#try_update` API. The reason this was changed was to
+  #     avoid raising exceptions (which are inherently slow) by default. For more
+  #     info: https://github.com/ruby-concurrency/concurrent-ruby/pull/336
+  #   @return [Object] the new value
+  #   @raise [Concurrent::ConcurrentUpdateError] if the update fails
+  class AtomicReference < AtomicReferenceImplementation
+
+    # @return [String] Short string representation.
+    def to_s
+      format '%s value:%s>', super[0..-2], get
+    end
+
+    alias_method :inspect, :to_s
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/count_down_latch.rb

@@ -0,0 +1,100 @@
+require 'concurrent/utility/engine'
+require 'concurrent/atomic/mutex_count_down_latch'
+require 'concurrent/atomic/java_count_down_latch'
+
+module Concurrent
+
+  ###################################################################
+
+  # @!macro count_down_latch_method_initialize
+  #
+  #   Create a new `CountDownLatch` with the initial `count`.
+  #
+  #   @param [new] count the initial count
+  #
+  #   @raise [ArgumentError] if `count` is not an integer or is less than zero
+
+  # @!macro count_down_latch_method_wait
+  #
+  #   Block on the latch until the counter reaches zero or until `timeout` is reached.
+  #
+  #   @param [Fixnum] timeout the number of seconds to wait for the counter or `nil`
+  #     to block indefinitely
+  #   @return [Boolean] `true` if the `count` reaches zero else false on `timeout`
+
+  # @!macro count_down_latch_method_count_down
+  #
+  #   Signal the latch to decrement the counter. Will signal all blocked threads when
+  #   the `count` reaches zero.
+
+  # @!macro count_down_latch_method_count
+  #
+  #   The current value of the counter.
+  #
+  #   @return [Fixnum] the current value of the counter
+
+  ###################################################################
+
+  # @!macro count_down_latch_public_api
+  #
+  #   @!method initialize(count = 1)
+  #     @!macro count_down_latch_method_initialize
+  #
+  #   @!method wait(timeout = nil)
+  #     @!macro count_down_latch_method_wait
+  #
+  #   @!method count_down
+  #     @!macro count_down_latch_method_count_down
+  #
+  #   @!method count
+  #     @!macro count_down_latch_method_count
+
+  ###################################################################
+
+  # @!visibility private
+  # @!macro internal_implementation_note
+  CountDownLatchImplementation = case
+                                 when Concurrent.on_jruby?
+                                   JavaCountDownLatch
+                                 else
+                                   MutexCountDownLatch
+                                 end
+  private_constant :CountDownLatchImplementation
+
+  # @!macro count_down_latch
+  #
+  #   A synchronization object that allows one thread to wait on multiple other threads.
+  #   The thread that will wait creates a `CountDownLatch` and sets the initial value
+  #   (normally equal to the number of other threads). The initiating thread passes the
+  #   latch to the other threads then waits for the other threads by calling the `#wait`
+  #   method. Each of the other threads calls `#count_down` when done with its work.
+  #   When the latch counter reaches zero the waiting thread is unblocked and continues
+  #   with its work. A `CountDownLatch` can be used only once. Its value cannot be reset.
+  #
+  # @!macro count_down_latch_public_api
+  # @example Waiter and Decrementer
+  #   latch = Concurrent::CountDownLatch.new(3)
+  #
+  #   waiter = Thread.new do
+  #     latch.wait()
+  #     puts ("Waiter released")
+  #   end
+  #
+  #   decrementer = Thread.new do
+  #     sleep(1)
+  #     latch.count_down
+  #     puts latch.count
+  #
+  #     sleep(1)
+  #     latch.count_down
+  #     puts latch.count
+  #
+  #     sleep(1)
+  #     latch.count_down
+  #     puts latch.count
+  #   end
+  #
+  #   [waiter, decrementer].each(&:join)
+  class CountDownLatch < CountDownLatchImplementation
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/cyclic_barrier.rb

@@ -0,0 +1,128 @@
+require 'concurrent/synchronization/lockable_object'
+require 'concurrent/utility/native_integer'
+
+module Concurrent
+
+  # A synchronization aid that allows a set of threads to all wait for each
+  # other to reach a common barrier point.
+  # @example
+  #   barrier = Concurrent::CyclicBarrier.new(3)
+  #   jobs    = Array.new(3) { |i| -> { sleep i; p done: i } }
+  #   process = -> (i) do
+  #     # waiting to start at the same time
+  #     barrier.wait
+  #     # execute job
+  #     jobs[i].call
+  #     # wait for others to finish
+  #     barrier.wait
+  #   end
+  #   threads = 2.times.map do |i|
+  #     Thread.new(i, &process)
+  #   end
+  #
+  #   # use main as well
+  #   process.call 2
+  #
+  #   # here we can be sure that all jobs are processed
+  class CyclicBarrier < Synchronization::LockableObject
+
+    # @!visibility private
+    Generation = Struct.new(:status)
+    private_constant :Generation
+
+    # Create a new `CyclicBarrier` that waits for `parties` threads
+    #
+    # @param [Fixnum] parties the number of parties
+    # @yield an optional block that will be executed that will be executed after
+    #  the last thread arrives and before the others are released
+    #
+    # @raise [ArgumentError] if `parties` is not an integer or is less than zero
+    def initialize(parties, &block)
+      Utility::NativeInteger.ensure_integer_and_bounds parties
+      Utility::NativeInteger.ensure_positive_and_no_zero parties
+
+      super(&nil)
+      synchronize { ns_initialize parties, &block }
+    end
+
+    # @return [Fixnum] the number of threads needed to pass the barrier
+    def parties
+      synchronize { @parties }
+    end
+
+    # @return [Fixnum] the number of threads currently waiting on the barrier
+    def number_waiting
+      synchronize { @number_waiting }
+    end
+
+    # Blocks on the barrier until the number of waiting threads is equal to
+    # `parties` or until `timeout` is reached or `reset` is called
+    # If a block has been passed to the constructor, it will be executed once by
+    #  the last arrived thread before releasing the others
+    # @param [Fixnum] timeout the number of seconds to wait for the counter or
+    #  `nil` to block indefinitely
+    # @return [Boolean] `true` if the `count` reaches zero else false on
+    #  `timeout` or on `reset` or if the barrier is broken
+    def wait(timeout = nil)
+      synchronize do
+
+        return false unless @generation.status == :waiting
+
+        @number_waiting += 1
+
+        if @number_waiting == @parties
+          @action.call if @action
+          ns_generation_done @generation, :fulfilled
+          true
+        else
+          generation = @generation
+          if ns_wait_until(timeout) { generation.status != :waiting }
+            generation.status == :fulfilled
+          else
+            ns_generation_done generation, :broken, false
+            false
+          end
+        end
+      end
+    end
+
+    # resets the barrier to its initial state
+    # If there is at least one waiting thread, it will be woken up, the `wait`
+    # method will return false and the barrier will be broken
+    # If the barrier is broken, this method restores it to the original state
+    #
+    # @return [nil]
+    def reset
+      synchronize { ns_generation_done @generation, :reset }
+    end
+
+    # A barrier can be broken when:
+    # - a thread called the `reset` method while at least one other thread was waiting
+    # - at least one thread timed out on `wait` method
+    #
+    # A broken barrier can be restored using `reset` it's safer to create a new one
+    # @return [Boolean] true if the barrier is broken otherwise false
+    def broken?
+      synchronize { @generation.status != :waiting }
+    end
+
+    protected
+
+    def ns_generation_done(generation, status, continue = true)
+      generation.status = status
+      ns_next_generation if continue
+      ns_broadcast
+    end
+
+    def ns_next_generation
+      @generation     = Generation.new(:waiting)
+      @number_waiting = 0
+    end
+
+    def ns_initialize(parties, &block)
+      @parties = parties
+      @action  = block
+      ns_next_generation
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/event.rb

@@ -0,0 +1,109 @@
+require 'thread'
+require 'concurrent/synchronization/lockable_object'
+
+module Concurrent
+
+  # Old school kernel-style event reminiscent of Win32 programming in C++.
+  #
+  # When an `Event` is created it is in the `unset` state. Threads can choose to
+  # `#wait` on the event, blocking until released by another thread. When one
+  # thread wants to alert all blocking threads it calls the `#set` method which
+  # will then wake up all listeners. Once an `Event` has been set it remains set.
+  # New threads calling `#wait` will return immediately. An `Event` may be
+  # `#reset` at any time once it has been set.
+  #
+  # @see http://msdn.microsoft.com/en-us/library/windows/desktop/ms682655.aspx
+  # @example
+  #   event = Concurrent::Event.new
+  #
+  #   t1 = Thread.new do
+  #     puts "t1 is waiting"
+  #     event.wait(1)
+  #     puts "event occurred"
+  #   end
+  #
+  #   t2 = Thread.new do
+  #     puts "t2 calling set"
+  #     event.set
+  #   end
+  #
+  #   [t1, t2].each(&:join)
+  #
+  #   # prints:
+  #   # t1 is waiting
+  #   # t2 calling set
+  #   # event occurred
+  class Event < Synchronization::LockableObject
+
+    # Creates a new `Event` in the unset state. Threads calling `#wait` on the
+    # `Event` will block.
+    def initialize
+      super
+      synchronize { ns_initialize }
+    end
+
+    # Is the object in the set state?
+    #
+    # @return [Boolean] indicating whether or not the `Event` has been set
+    def set?
+      synchronize { @set }
+    end
+
+    # Trigger the event, setting the state to `set` and releasing all threads
+    # waiting on the event. Has no effect if the `Event` has already been set.
+    #
+    # @return [Boolean] should always return `true`
+    def set
+      synchronize { ns_set }
+    end
+
+    def try?
+      synchronize { @set ? false : ns_set }
+    end
+
+    # Reset a previously set event back to the `unset` state.
+    # Has no effect if the `Event` has not yet been set.
+    #
+    # @return [Boolean] should always return `true`
+    def reset
+      synchronize do
+        if @set
+          @set       = false
+          @iteration +=1
+        end
+        true
+      end
+    end
+
+    # Wait a given number of seconds for the `Event` to be set by another
+    # thread. Will wait forever when no `timeout` value is given. Returns
+    # immediately if the `Event` has already been set.
+    #
+    # @return [Boolean] true if the `Event` was set before timeout else false
+    def wait(timeout = nil)
+      synchronize do
+        unless @set
+          iteration = @iteration
+          ns_wait_until(timeout) { iteration < @iteration || @set }
+        else
+          true
+        end
+      end
+    end
+
+    protected
+
+    def ns_set
+      unless @set
+        @set = true
+        ns_broadcast
+      end
+      true
+    end
+
+    def ns_initialize
+      @set       = false
+      @iteration = 0
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/fiber_local_var.rb

@@ -0,0 +1,109 @@
+require 'concurrent/constants'
+require_relative 'locals'
+
+module Concurrent
+
+  # A `FiberLocalVar` is a variable where the value is different for each fiber.
+  # Each variable may have a default value, but when you modify the variable only
+  # the current fiber will ever see that change.
+  #
+  # This is similar to Ruby's built-in fiber-local variables (`Thread.current[:name]`),
+  # but with these major advantages:
+  # * `FiberLocalVar` has its own identity, it doesn't need a Symbol.
+  # * Each Ruby's built-in fiber-local variable leaks some memory forever (it's a Symbol held forever on the fiber),
+  #   so it's only OK to create a small amount of them.
+  #   `FiberLocalVar` has no such issue and it is fine to create many of them.
+  # * Ruby's built-in fiber-local variables leak forever the value set on each fiber (unless set to nil explicitly).
+  #   `FiberLocalVar` automatically removes the mapping for each fiber once the `FiberLocalVar` instance is GC'd.
+  #
+  # @example
+  #   v = FiberLocalVar.new(14)
+  #   v.value #=> 14
+  #   v.value = 2
+  #   v.value #=> 2
+  #
+  # @example
+  #   v = FiberLocalVar.new(14)
+  #
+  #   Fiber.new do
+  #     v.value #=> 14
+  #     v.value = 1
+  #     v.value #=> 1
+  #   end.resume
+  #
+  #   Fiber.new do
+  #     v.value #=> 14
+  #     v.value = 2
+  #     v.value #=> 2
+  #   end.resume
+  #
+  #   v.value #=> 14
+  class FiberLocalVar
+    LOCALS = FiberLocals.new
+
+    # Creates a fiber local variable.
+    #
+    # @param [Object] default the default value when otherwise unset
+    # @param [Proc] default_block Optional block that gets called to obtain the
+    #   default value for each fiber
+    def initialize(default = nil, &default_block)
+      if default && block_given?
+        raise ArgumentError, "Cannot use both value and block as default value"
+      end
+
+      if block_given?
+        @default_block = default_block
+        @default = nil
+      else
+        @default_block = nil
+        @default = default
+      end
+
+      @index = LOCALS.next_index(self)
+    end
+
+    # Returns the value in the current fiber's copy of this fiber-local variable.
+    #
+    # @return [Object] the current value
+    def value
+      LOCALS.fetch(@index) { default }
+    end
+
+    # Sets the current fiber's copy of this fiber-local variable to the specified value.
+    #
+    # @param [Object] value the value to set
+    # @return [Object] the new value
+    def value=(value)
+      LOCALS.set(@index, value)
+    end
+
+    # Bind the given value to fiber local storage during
+    # execution of the given block.
+    #
+    # @param [Object] value the value to bind
+    # @yield the operation to be performed with the bound variable
+    # @return [Object] the value
+    def bind(value)
+      if block_given?
+        old_value = self.value
+        self.value = value
+        begin
+          yield
+        ensure
+          self.value = old_value
+        end
+      end
+    end
+
+    protected
+
+    # @!visibility private
+    def default
+      if @default_block
+        self.value = @default_block.call
+      else
+        @default
+      end
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/java_count_down_latch.rb

@@ -0,0 +1,43 @@
+if Concurrent.on_jruby?
+  require 'concurrent/utility/native_extension_loader'
+
+  module Concurrent
+
+    # @!macro count_down_latch
+    # @!visibility private
+    # @!macro internal_implementation_note
+    class JavaCountDownLatch
+
+      # @!macro count_down_latch_method_initialize
+      def initialize(count = 1)
+        Utility::NativeInteger.ensure_integer_and_bounds(count)
+        Utility::NativeInteger.ensure_positive(count)
+        @latch = java.util.concurrent.CountDownLatch.new(count)
+      end
+
+      # @!macro count_down_latch_method_wait
+      def wait(timeout = nil)
+        result = nil
+        if timeout.nil?
+          Synchronization::JRuby.sleep_interruptibly { @latch.await }
+          result = true
+        else
+          Synchronization::JRuby.sleep_interruptibly do
+            result = @latch.await(1000 * timeout, java.util.concurrent.TimeUnit::MILLISECONDS)
+          end
+        end
+        result
+      end
+
+      # @!macro count_down_latch_method_count_down
+      def count_down
+        @latch.countDown
+      end
+
+      # @!macro count_down_latch_method_count
+      def count
+        @latch.getCount
+      end
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/locals.rb

@@ -0,0 +1,189 @@
+require 'fiber'
+require 'concurrent/utility/engine'
+require 'concurrent/constants'
+
+module Concurrent
+  # @!visibility private
+  # @!macro internal_implementation_note
+  #
+  # An abstract implementation of local storage, with sub-classes for
+  # per-thread and per-fiber locals.
+  #
+  # Each execution context (EC, thread or fiber) has a lazily initialized array
+  # of local variable values. Each time a new local variable is created, we
+  # allocate an "index" for it.
+  #
+  # For example, if the allocated index is 1, that means slot #1 in EVERY EC's
+  # locals array will be used for the value of that variable.
+  #
+  # The good thing about using a per-EC structure to hold values, rather than
+  # a global, is that no synchronization is needed when reading and writing
+  # those values (since the structure is only ever accessed by a single
+  # thread).
+  #
+  # Of course, when a local variable is GC'd, 1) we need to recover its index
+  # for use by other new local variables (otherwise the locals arrays could
+  # get bigger and bigger with time), and 2) we need to null out all the
+  # references held in the now-unused slots (both to avoid blocking GC of those
+  # objects, and also to prevent "stale" values from being passed on to a new
+  # local when the index is reused).
+  #
+  # Because we need to null out freed slots, we need to keep references to
+  # ALL the locals arrays, so we can null out the appropriate slots in all of
+  # them. This is why we need to use a finalizer to clean up the locals array
+  # when the EC goes out of scope.
+  class AbstractLocals
+    def initialize
+      @free = []
+      @lock = Mutex.new
+      @all_arrays = {}
+      @next = 0
+    end
+
+    def synchronize
+      @lock.synchronize { yield }
+    end
+
+    if Concurrent.on_cruby?
+      def weak_synchronize
+        yield
+      end
+    else
+      alias_method :weak_synchronize, :synchronize
+    end
+
+    def next_index(local)
+      index = synchronize do
+        if @free.empty?
+          @next += 1
+        else
+          @free.pop
+        end
+      end
+
+      # When the local goes out of scope, we should free the associated index
+      # and all values stored into it.
+      ObjectSpace.define_finalizer(local, local_finalizer(index))
+
+      index
+    end
+
+    def free_index(index)
+      weak_synchronize do
+        # The cost of GC'ing a TLV is linear in the number of ECs using local
+        # variables. But that is natural! More ECs means more storage is used
+        # per local variable. So naturally more CPU time is required to free
+        # more storage.
+        #
+        # DO NOT use each_value which might conflict with new pair assignment
+        # into the hash in #set method.
+        @all_arrays.values.each do |locals|
+          locals[index] = nil
+        end
+
+        # free index has to be published after the arrays are cleared:
+        @free << index
+      end
+    end
+
+    def fetch(index)
+      locals = self.locals
+      value = locals ? locals[index] : nil
+
+      if nil == value
+        yield
+      elsif NULL.equal?(value)
+        nil
+      else
+        value
+      end
+    end
+
+    def set(index, value)
+      locals = self.locals!
+      locals[index] = (nil == value ? NULL : value)
+
+      value
+    end
+
+    private
+
+    # When the local goes out of scope, clean up that slot across all locals currently assigned.
+    def local_finalizer(index)
+      proc do
+        free_index(index)
+      end
+    end
+
+    # When a thread/fiber goes out of scope, remove the array from @all_arrays.
+    def thread_fiber_finalizer(array_object_id)
+      proc do
+        weak_synchronize do
+          @all_arrays.delete(array_object_id)
+        end
+      end
+    end
+
+    # Returns the locals for the current scope, or nil if none exist.
+    def locals
+      raise NotImplementedError
+    end
+
+    # Returns the locals for the current scope, creating them if necessary.
+    def locals!
+      raise NotImplementedError
+    end
+  end
+
+  # @!visibility private
+  # @!macro internal_implementation_note
+  # An array-backed storage of indexed variables per thread.
+  class ThreadLocals < AbstractLocals
+    def locals
+      Thread.current.thread_variable_get(:concurrent_thread_locals)
+    end
+
+    def locals!
+      thread = Thread.current
+      locals = thread.thread_variable_get(:concurrent_thread_locals)
+
+      unless locals
+        locals = thread.thread_variable_set(:concurrent_thread_locals, [])
+        weak_synchronize do
+          @all_arrays[locals.object_id] = locals
+        end
+        # When the thread goes out of scope, we should delete the associated locals:
+        ObjectSpace.define_finalizer(thread, thread_fiber_finalizer(locals.object_id))
+      end
+
+      locals
+    end
+  end
+
+  # @!visibility private
+  # @!macro internal_implementation_note
+  # An array-backed storage of indexed variables per fiber.
+  class FiberLocals < AbstractLocals
+    def locals
+      Thread.current[:concurrent_fiber_locals]
+    end
+
+    def locals!
+      thread = Thread.current
+      locals = thread[:concurrent_fiber_locals]
+
+      unless locals
+        locals = thread[:concurrent_fiber_locals] = []
+        weak_synchronize do
+          @all_arrays[locals.object_id] = locals
+        end
+        # When the fiber goes out of scope, we should delete the associated locals:
+        ObjectSpace.define_finalizer(Fiber.current, thread_fiber_finalizer(locals.object_id))
+      end
+
+      locals
+    end
+  end
+
+  private_constant :AbstractLocals, :ThreadLocals, :FiberLocals
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/lock_local_var.rb

@@ -0,0 +1,28 @@
+require 'concurrent/utility/engine'
+require_relative 'fiber_local_var'
+require_relative 'thread_local_var'
+
+module Concurrent
+  # @!visibility private
+  def self.mutex_owned_per_thread?
+    return false if Concurrent.on_jruby? || Concurrent.on_truffleruby?
+
+    mutex = Mutex.new
+    # Lock the mutex:
+    mutex.synchronize do
+      # Check if the mutex is still owned in a child fiber:
+      Fiber.new { mutex.owned? }.resume
+    end
+  end
+
+  if mutex_owned_per_thread?
+    LockLocalVar = ThreadLocalVar
+  else
+    LockLocalVar = FiberLocalVar
+  end
+
+  # Either {FiberLocalVar} or {ThreadLocalVar} depending on whether Mutex (and Monitor)
+  # are held, respectively, per Fiber or per Thread.
+  class LockLocalVar
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/mutex_atomic_boolean.rb

@@ -0,0 +1,68 @@
+require 'concurrent/synchronization/safe_initialization'
+
+module Concurrent
+
+  # @!macro atomic_boolean
+  # @!visibility private
+  # @!macro internal_implementation_note
+  class MutexAtomicBoolean
+    extend Concurrent::Synchronization::SafeInitialization
+
+    # @!macro atomic_boolean_method_initialize
+    def initialize(initial = false)
+      super()
+      @Lock = ::Mutex.new
+      @value = !!initial
+    end
+
+    # @!macro atomic_boolean_method_value_get
+    def value
+      synchronize { @value }
+    end
+
+    # @!macro atomic_boolean_method_value_set
+    def value=(value)
+      synchronize { @value = !!value }
+    end
+
+    # @!macro atomic_boolean_method_true_question
+    def true?
+      synchronize { @value }
+    end
+
+    # @!macro atomic_boolean_method_false_question
+    def false?
+      synchronize { !@value }
+    end
+
+    # @!macro atomic_boolean_method_make_true
+    def make_true
+      synchronize { ns_make_value(true) }
+    end
+
+    # @!macro atomic_boolean_method_make_false
+    def make_false
+      synchronize { ns_make_value(false) }
+    end
+
+    protected
+
+    # @!visibility private
+    def synchronize
+      if @Lock.owned?
+        yield
+      else
+        @Lock.synchronize { yield }
+      end
+    end
+
+    private
+
+    # @!visibility private
+    def ns_make_value(value)
+      old = @value
+      @value = value
+      old != @value
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/mutex_atomic_fixnum.rb

@@ -0,0 +1,81 @@
+require 'concurrent/synchronization/safe_initialization'
+require 'concurrent/utility/native_integer'
+
+module Concurrent
+
+  # @!macro atomic_fixnum
+  # @!visibility private
+  # @!macro internal_implementation_note
+  class MutexAtomicFixnum
+    extend Concurrent::Synchronization::SafeInitialization
+
+    # @!macro atomic_fixnum_method_initialize
+    def initialize(initial = 0)
+      super()
+      @Lock = ::Mutex.new
+      ns_set(initial)
+    end
+
+    # @!macro atomic_fixnum_method_value_get
+    def value
+      synchronize { @value }
+    end
+
+    # @!macro atomic_fixnum_method_value_set
+    def value=(value)
+      synchronize { ns_set(value) }
+    end
+
+    # @!macro atomic_fixnum_method_increment
+    def increment(delta = 1)
+      synchronize { ns_set(@value + delta.to_i) }
+    end
+
+    alias_method :up, :increment
+
+    # @!macro atomic_fixnum_method_decrement
+    def decrement(delta = 1)
+      synchronize { ns_set(@value - delta.to_i) }
+    end
+
+    alias_method :down, :decrement
+
+    # @!macro atomic_fixnum_method_compare_and_set
+    def compare_and_set(expect, update)
+      synchronize do
+        if @value == expect.to_i
+          @value = update.to_i
+          true
+        else
+          false
+        end
+      end
+    end
+
+    # @!macro atomic_fixnum_method_update
+    def update
+      synchronize do
+        @value = yield @value
+      end
+    end
+
+    protected
+
+    # @!visibility private
+    def synchronize
+      if @Lock.owned?
+        yield
+      else
+        @Lock.synchronize { yield }
+      end
+    end
+
+    private
+
+    # @!visibility private
+    def ns_set(value)
+      Utility::NativeInteger.ensure_integer_and_bounds value
+      @value = value
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/mutex_count_down_latch.rb

@@ -0,0 +1,44 @@
+require 'concurrent/synchronization/lockable_object'
+require 'concurrent/utility/native_integer'
+
+module Concurrent
+
+  # @!macro count_down_latch
+  # @!visibility private
+  # @!macro internal_implementation_note
+  class MutexCountDownLatch < Synchronization::LockableObject
+
+    # @!macro count_down_latch_method_initialize
+    def initialize(count = 1)
+      Utility::NativeInteger.ensure_integer_and_bounds count
+      Utility::NativeInteger.ensure_positive count
+
+      super()
+      synchronize { ns_initialize count }
+    end
+
+    # @!macro count_down_latch_method_wait
+    def wait(timeout = nil)
+      synchronize { ns_wait_until(timeout) { @count == 0 } }
+    end
+
+    # @!macro count_down_latch_method_count_down
+    def count_down
+      synchronize do
+        @count -= 1 if @count > 0
+        ns_broadcast if @count == 0
+      end
+    end
+
+    # @!macro count_down_latch_method_count
+    def count
+      synchronize { @count }
+    end
+
+    protected
+
+    def ns_initialize(count)
+      @count = count
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/mutex_semaphore.rb

@@ -0,0 +1,131 @@
+require 'concurrent/synchronization/lockable_object'
+require 'concurrent/utility/native_integer'
+
+module Concurrent
+
+  # @!macro semaphore
+  # @!visibility private
+  # @!macro internal_implementation_note
+  class MutexSemaphore < Synchronization::LockableObject
+
+    # @!macro semaphore_method_initialize
+    def initialize(count)
+      Utility::NativeInteger.ensure_integer_and_bounds count
+
+      super()
+      synchronize { ns_initialize count }
+    end
+
+    # @!macro semaphore_method_acquire
+    def acquire(permits = 1)
+      Utility::NativeInteger.ensure_integer_and_bounds permits
+      Utility::NativeInteger.ensure_positive permits
+
+      synchronize do
+        try_acquire_timed(permits, nil)
+      end
+
+      return unless block_given?
+
+      begin
+        yield
+      ensure
+        release(permits)
+      end
+    end
+
+    # @!macro semaphore_method_available_permits
+    def available_permits
+      synchronize { @free }
+    end
+
+    # @!macro semaphore_method_drain_permits
+    #
+    #   Acquires and returns all permits that are immediately available.
+    #
+    #   @return [Integer]
+    def drain_permits
+      synchronize do
+        @free.tap { |_| @free = 0 }
+      end
+    end
+
+    # @!macro semaphore_method_try_acquire
+    def try_acquire(permits = 1, timeout = nil)
+      Utility::NativeInteger.ensure_integer_and_bounds permits
+      Utility::NativeInteger.ensure_positive permits
+
+      acquired = synchronize do
+        if timeout.nil?
+          try_acquire_now(permits)
+        else
+          try_acquire_timed(permits, timeout)
+        end
+      end
+
+      return acquired unless block_given?
+      return unless acquired
+
+      begin
+        yield
+      ensure
+        release(permits)
+      end
+    end
+
+    # @!macro semaphore_method_release
+    def release(permits = 1)
+      Utility::NativeInteger.ensure_integer_and_bounds permits
+      Utility::NativeInteger.ensure_positive permits
+
+      synchronize do
+        @free += permits
+        permits.times { ns_signal }
+      end
+      nil
+    end
+
+    # Shrinks the number of available permits by the indicated reduction.
+    #
+    # @param [Fixnum] reduction Number of permits to remove.
+    #
+    # @raise [ArgumentError] if `reduction` is not an integer or is negative
+    #
+    # @raise [ArgumentError] if `@free` - `@reduction` is less than zero
+    #
+    # @return [nil]
+    #
+    # @!visibility private
+    def reduce_permits(reduction)
+      Utility::NativeInteger.ensure_integer_and_bounds reduction
+      Utility::NativeInteger.ensure_positive reduction
+
+      synchronize { @free -= reduction }
+      nil
+    end
+
+    protected
+
+    # @!visibility private
+    def ns_initialize(count)
+      @free = count
+    end
+
+    private
+
+    # @!visibility private
+    def try_acquire_now(permits)
+      if @free >= permits
+        @free -= permits
+        true
+      else
+        false
+      end
+    end
+
+    # @!visibility private
+    def try_acquire_timed(permits, timeout)
+      ns_wait_until(timeout) { try_acquire_now(permits) }
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/read_write_lock.rb

@@ -0,0 +1,255 @@
+require 'thread'
+require 'concurrent/atomic/atomic_fixnum'
+require 'concurrent/errors'
+require 'concurrent/synchronization/object'
+require 'concurrent/synchronization/lock'
+
+module Concurrent
+
+  # Ruby read-write lock implementation
+  #
+  # Allows any number of concurrent readers, but only one concurrent writer
+  # (And if the "write" lock is taken, any readers who come along will have to wait)
+  #
+  # If readers are already active when a writer comes along, the writer will wait for
+  # all the readers to finish before going ahead.
+  # Any additional readers that come when the writer is already waiting, will also
+  # wait (so writers are not starved).
+  #
+  # This implementation is based on `java.util.concurrent.ReentrantReadWriteLock`.
+  #
+  # @example
+  #   lock = Concurrent::ReadWriteLock.new
+  #   lock.with_read_lock  { data.retrieve }
+  #   lock.with_write_lock { data.modify! }
+  #
+  # @note Do **not** try to acquire the write lock while already holding a read lock
+  #   **or** try to acquire the write lock while you already have it.
+  #   This will lead to deadlock
+  #
+  # @see http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/locks/ReentrantReadWriteLock.html java.util.concurrent.ReentrantReadWriteLock
+  class ReadWriteLock < Synchronization::Object
+
+    # @!visibility private
+    WAITING_WRITER = 1 << 15
+
+    # @!visibility private
+    RUNNING_WRITER = 1 << 29
+
+    # @!visibility private
+    MAX_READERS    = WAITING_WRITER - 1
+
+    # @!visibility private
+    MAX_WRITERS    = RUNNING_WRITER - MAX_READERS - 1
+
+    safe_initialization!
+
+    # Implementation notes:
+    # A goal is to make the uncontended path for both readers/writers lock-free
+    # Only if there is reader-writer or writer-writer contention, should locks be used
+    # Internal state is represented by a single integer ("counter"), and updated
+    #  using atomic compare-and-swap operations
+    # When the counter is 0, the lock is free
+    # Each reader increments the counter by 1 when acquiring a read lock
+    #   (and decrements by 1 when releasing the read lock)
+    # The counter is increased by (1 << 15) for each writer waiting to acquire the
+    #   write lock, and by (1 << 29) if the write lock is taken
+
+    # Create a new `ReadWriteLock` in the unlocked state.
+    def initialize
+      super()
+      @Counter   = AtomicFixnum.new(0) # single integer which represents lock state
+      @ReadLock  = Synchronization::Lock.new
+      @WriteLock = Synchronization::Lock.new
+    end
+
+    # Execute a block operation within a read lock.
+    #
+    # @yield the task to be performed within the lock.
+    #
+    # @return [Object] the result of the block operation.
+    #
+    # @raise [ArgumentError] when no block is given.
+    # @raise [Concurrent::ResourceLimitError] if the maximum number of readers
+    #   is exceeded.
+    def with_read_lock
+      raise ArgumentError.new('no block given') unless block_given?
+      acquire_read_lock
+      begin
+        yield
+      ensure
+        release_read_lock
+      end
+    end
+
+    # Execute a block operation within a write lock.
+    #
+    # @yield the task to be performed within the lock.
+    #
+    # @return [Object] the result of the block operation.
+    #
+    # @raise [ArgumentError] when no block is given.
+    # @raise [Concurrent::ResourceLimitError] if the maximum number of readers
+    #   is exceeded.
+    def with_write_lock
+      raise ArgumentError.new('no block given') unless block_given?
+      acquire_write_lock
+      begin
+        yield
+      ensure
+        release_write_lock
+      end
+    end
+
+    # Acquire a read lock. If a write lock has been acquired will block until
+    # it is released. Will not block if other read locks have been acquired.
+    #
+    # @return [Boolean] true if the lock is successfully acquired
+    #
+    # @raise [Concurrent::ResourceLimitError] if the maximum number of readers
+    #   is exceeded.
+    def acquire_read_lock
+      while true
+        c = @Counter.value
+        raise ResourceLimitError.new('Too many reader threads') if max_readers?(c)
+
+        # If a writer is waiting when we first queue up, we need to wait
+        if waiting_writer?(c)
+          @ReadLock.wait_until { !waiting_writer? }
+
+          # after a reader has waited once, they are allowed to "barge" ahead of waiting writers
+          # but if a writer is *running*, the reader still needs to wait (naturally)
+          while true
+            c = @Counter.value
+            if running_writer?(c)
+              @ReadLock.wait_until { !running_writer? }
+            else
+              return if @Counter.compare_and_set(c, c+1)
+            end
+          end
+        else
+          break if @Counter.compare_and_set(c, c+1)
+        end
+      end
+      true
+    end
+
+    # Release a previously acquired read lock.
+    #
+    # @return [Boolean] true if the lock is successfully released
+    def release_read_lock
+      while true
+        c = @Counter.value
+        if @Counter.compare_and_set(c, c-1)
+          # If one or more writers were waiting, and we were the last reader, wake a writer up
+          if waiting_writer?(c) && running_readers(c) == 1
+            @WriteLock.signal
+          end
+          break
+        end
+      end
+      true
+    end
+
+    # Acquire a write lock. Will block and wait for all active readers and writers.
+    #
+    # @return [Boolean] true if the lock is successfully acquired
+    #
+    # @raise [Concurrent::ResourceLimitError] if the maximum number of writers
+    #   is exceeded.
+    def acquire_write_lock
+      while true
+        c = @Counter.value
+        raise ResourceLimitError.new('Too many writer threads') if max_writers?(c)
+
+        if c == 0 # no readers OR writers running
+          # if we successfully swap the RUNNING_WRITER bit on, then we can go ahead
+          break if @Counter.compare_and_set(0, RUNNING_WRITER)
+        elsif @Counter.compare_and_set(c, c+WAITING_WRITER)
+          while true
+            # Now we have successfully incremented, so no more readers will be able to increment
+            #   (they will wait instead)
+            # However, readers OR writers could decrement right here, OR another writer could increment
+            @WriteLock.wait_until do
+              # So we have to do another check inside the synchronized section
+              # If a writer OR reader is running, then go to sleep
+              c = @Counter.value
+              !running_writer?(c) && !running_readers?(c)
+            end
+
+            # We just came out of a wait
+            # If we successfully turn the RUNNING_WRITER bit on with an atomic swap,
+            # Then we are OK to stop waiting and go ahead
+            # Otherwise go back and wait again
+            c = @Counter.value
+            break if !running_writer?(c) && !running_readers?(c) && @Counter.compare_and_set(c, c+RUNNING_WRITER-WAITING_WRITER)
+          end
+          break
+        end
+      end
+      true
+    end
+
+    # Release a previously acquired write lock.
+    #
+    # @return [Boolean] true if the lock is successfully released
+    def release_write_lock
+      return true unless running_writer?
+      c = @Counter.update { |counter| counter - RUNNING_WRITER }
+      @ReadLock.broadcast
+      @WriteLock.signal if waiting_writers(c) > 0
+      true
+    end
+
+    # Queries if the write lock is held by any thread.
+    #
+    # @return [Boolean] true if the write lock is held else false`
+    def write_locked?
+      @Counter.value >= RUNNING_WRITER
+    end
+
+    # Queries whether any threads are waiting to acquire the read or write lock.
+    #
+    # @return [Boolean] true if any threads are waiting for a lock else false
+    def has_waiters?
+      waiting_writer?(@Counter.value)
+    end
+
+    private
+
+    # @!visibility private
+    def running_readers(c = @Counter.value)
+      c & MAX_READERS
+    end
+
+    # @!visibility private
+    def running_readers?(c = @Counter.value)
+      (c & MAX_READERS) > 0
+    end
+
+    # @!visibility private
+    def running_writer?(c = @Counter.value)
+      c >= RUNNING_WRITER
+    end
+
+    # @!visibility private
+    def waiting_writers(c = @Counter.value)
+      (c & MAX_WRITERS) / WAITING_WRITER
+    end
+
+    # @!visibility private
+    def waiting_writer?(c = @Counter.value)
+      c >= WAITING_WRITER
+    end
+
+    # @!visibility private
+    def max_readers?(c = @Counter.value)
+      (c & MAX_READERS) == MAX_READERS
+    end
+
+    # @!visibility private
+    def max_writers?(c = @Counter.value)
+      (c & MAX_WRITERS) == MAX_WRITERS
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/reentrant_read_write_lock.rb

@@ -0,0 +1,379 @@
+require 'thread'
+require 'concurrent/atomic/atomic_reference'
+require 'concurrent/atomic/atomic_fixnum'
+require 'concurrent/errors'
+require 'concurrent/synchronization/object'
+require 'concurrent/synchronization/lock'
+require 'concurrent/atomic/lock_local_var'
+
+module Concurrent
+
+  # Re-entrant read-write lock implementation
+  #
+  # Allows any number of concurrent readers, but only one concurrent writer
+  # (And while the "write" lock is taken, no read locks can be obtained either.
+  # Hence, the write lock can also be called an "exclusive" lock.)
+  #
+  # If another thread has taken a read lock, any thread which wants a write lock
+  # will block until all the readers release their locks. However, once a thread
+  # starts waiting to obtain a write lock, any additional readers that come along
+  # will also wait (so writers are not starved).
+  #
+  # A thread can acquire both a read and write lock at the same time. A thread can
+  # also acquire a read lock OR a write lock more than once. Only when the read (or
+  # write) lock is released as many times as it was acquired, will the thread
+  # actually let it go, allowing other threads which might have been waiting
+  # to proceed. Therefore the lock can be upgraded by first acquiring
+  # read lock and then write lock and that the lock can be downgraded by first
+  # having both read and write lock a releasing just the write lock.
+  #
+  # If both read and write locks are acquired by the same thread, it is not strictly
+  # necessary to release them in the same order they were acquired. In other words,
+  # the following code is legal:
+  #
+  # @example
+  #   lock = Concurrent::ReentrantReadWriteLock.new
+  #   lock.acquire_write_lock
+  #   lock.acquire_read_lock
+  #   lock.release_write_lock
+  #   # At this point, the current thread is holding only a read lock, not a write
+  #   # lock. So other threads can take read locks, but not a write lock.
+  #   lock.release_read_lock
+  #   # Now the current thread is not holding either a read or write lock, so
+  #   # another thread could potentially acquire a write lock.
+  #
+  # This implementation was inspired by `java.util.concurrent.ReentrantReadWriteLock`.
+  #
+  # @example
+  #   lock = Concurrent::ReentrantReadWriteLock.new
+  #   lock.with_read_lock  { data.retrieve }
+  #   lock.with_write_lock { data.modify! }
+  #
+  # @see http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/locks/ReentrantReadWriteLock.html java.util.concurrent.ReentrantReadWriteLock
+  class ReentrantReadWriteLock < Synchronization::Object
+
+    # Implementation notes:
+    #
+    # A goal is to make the uncontended path for both readers/writers mutex-free
+    # Only if there is reader-writer or writer-writer contention, should mutexes be used
+    # Otherwise, a single CAS operation is all we need to acquire/release a lock
+    #
+    # Internal state is represented by a single integer ("counter"), and updated
+    #   using atomic compare-and-swap operations
+    # When the counter is 0, the lock is free
+    # Each thread which has one OR MORE read locks increments the counter by 1
+    #   (and decrements by 1 when releasing the read lock)
+    # The counter is increased by (1 << 15) for each writer waiting to acquire the
+    #   write lock, and by (1 << 29) if the write lock is taken
+    #
+    # Additionally, each thread uses a thread-local variable to count how many times
+    #   it has acquired a read lock, AND how many times it has acquired a write lock.
+    # It uses a similar trick; an increment of 1 means a read lock was taken, and
+    #   an increment of (1 << 15) means a write lock was taken
+    # This is what makes re-entrancy possible
+    #
+    # 2 rules are followed to ensure good liveness properties:
+    # 1) Once a writer has queued up and is waiting for a write lock, no other thread
+    #    can take a lock without waiting
+    # 2) When a write lock is released, readers are given the "first chance" to wake
+    #    up and acquire a read lock
+    # Following these rules means readers and writers tend to "take turns", so neither
+    #   can starve the other, even under heavy contention
+
+    # @!visibility private
+    READER_BITS    = 15
+    # @!visibility private
+    WRITER_BITS    = 14
+
+    # Used with @Counter:
+    # @!visibility private
+    WAITING_WRITER = 1 << READER_BITS
+    # @!visibility private
+    RUNNING_WRITER = 1 << (READER_BITS + WRITER_BITS)
+    # @!visibility private
+    MAX_READERS    = WAITING_WRITER - 1
+    # @!visibility private
+    MAX_WRITERS    = RUNNING_WRITER - MAX_READERS - 1
+
+    # Used with @HeldCount:
+    # @!visibility private
+    WRITE_LOCK_HELD = 1 << READER_BITS
+    # @!visibility private
+    READ_LOCK_MASK  = WRITE_LOCK_HELD - 1
+    # @!visibility private
+    WRITE_LOCK_MASK = MAX_WRITERS
+
+    safe_initialization!
+
+    # Create a new `ReentrantReadWriteLock` in the unlocked state.
+    def initialize
+      super()
+      @Counter    = AtomicFixnum.new(0)       # single integer which represents lock state
+      @ReadQueue  = Synchronization::Lock.new # used to queue waiting readers
+      @WriteQueue = Synchronization::Lock.new # used to queue waiting writers
+      @HeldCount  = LockLocalVar.new(0) # indicates # of R & W locks held by this thread
+    end
+
+    # Execute a block operation within a read lock.
+    #
+    # @yield the task to be performed within the lock.
+    #
+    # @return [Object] the result of the block operation.
+    #
+    # @raise [ArgumentError] when no block is given.
+    # @raise [Concurrent::ResourceLimitError] if the maximum number of readers
+    #   is exceeded.
+    def with_read_lock
+      raise ArgumentError.new('no block given') unless block_given?
+      acquire_read_lock
+      begin
+        yield
+      ensure
+        release_read_lock
+      end
+    end
+
+    # Execute a block operation within a write lock.
+    #
+    # @yield the task to be performed within the lock.
+    #
+    # @return [Object] the result of the block operation.
+    #
+    # @raise [ArgumentError] when no block is given.
+    # @raise [Concurrent::ResourceLimitError] if the maximum number of readers
+    #   is exceeded.
+    def with_write_lock
+      raise ArgumentError.new('no block given') unless block_given?
+      acquire_write_lock
+      begin
+        yield
+      ensure
+        release_write_lock
+      end
+    end
+
+    # Acquire a read lock. If a write lock is held by another thread, will block
+    # until it is released.
+    #
+    # @return [Boolean] true if the lock is successfully acquired
+    #
+    # @raise [Concurrent::ResourceLimitError] if the maximum number of readers
+    #   is exceeded.
+    def acquire_read_lock
+      if (held = @HeldCount.value) > 0
+        # If we already have a lock, there's no need to wait
+        if held & READ_LOCK_MASK == 0
+          # But we do need to update the counter, if we were holding a write
+          #   lock but not a read lock
+          @Counter.update { |c| c + 1 }
+        end
+        @HeldCount.value = held + 1
+        return true
+      end
+
+      while true
+        c = @Counter.value
+        raise ResourceLimitError.new('Too many reader threads') if max_readers?(c)
+
+        # If a writer is waiting OR running when we first queue up, we need to wait
+        if waiting_or_running_writer?(c)
+          # Before going to sleep, check again with the ReadQueue mutex held
+          @ReadQueue.synchronize do
+            @ReadQueue.ns_wait if waiting_or_running_writer?
+          end
+          # Note: the above 'synchronize' block could have used #wait_until,
+          #   but that waits repeatedly in a loop, checking the wait condition
+          #   each time it wakes up (to protect against spurious wakeups)
+          # But we are already in a loop, which is only broken when we successfully
+          #   acquire the lock! So we don't care about spurious wakeups, and would
+          #   rather not pay the extra overhead of using #wait_until
+
+          # After a reader has waited once, they are allowed to "barge" ahead of waiting writers
+          # But if a writer is *running*, the reader still needs to wait (naturally)
+          while true
+            c = @Counter.value
+            if running_writer?(c)
+              @ReadQueue.synchronize do
+                @ReadQueue.ns_wait if running_writer?
+              end
+            elsif @Counter.compare_and_set(c, c+1)
+              @HeldCount.value = held + 1
+              return true
+            end
+          end
+        elsif @Counter.compare_and_set(c, c+1)
+          @HeldCount.value = held + 1
+          return true
+        end
+      end
+    end
+
+    # Try to acquire a read lock and return true if we succeed. If it cannot be
+    # acquired immediately, return false.
+    #
+    # @return [Boolean] true if the lock is successfully acquired
+    def try_read_lock
+      if (held = @HeldCount.value) > 0
+        if held & READ_LOCK_MASK == 0
+          # If we hold a write lock, but not a read lock...
+          @Counter.update { |c| c + 1 }
+        end
+        @HeldCount.value = held + 1
+        return true
+      else
+        c = @Counter.value
+        if !waiting_or_running_writer?(c) && @Counter.compare_and_set(c, c+1)
+          @HeldCount.value = held + 1
+          return true
+        end
+      end
+      false
+    end
+
+    # Release a previously acquired read lock.
+    #
+    # @return [Boolean] true if the lock is successfully released
+    def release_read_lock
+      held = @HeldCount.value = @HeldCount.value - 1
+      rlocks_held = held & READ_LOCK_MASK
+      if rlocks_held == 0
+        c = @Counter.update { |counter| counter - 1 }
+        # If one or more writers were waiting, and we were the last reader, wake a writer up
+        if waiting_or_running_writer?(c) && running_readers(c) == 0
+          @WriteQueue.signal
+        end
+      elsif rlocks_held == READ_LOCK_MASK
+        raise IllegalOperationError, "Cannot release a read lock which is not held"
+      end
+      true
+    end
+
+    # Acquire a write lock. Will block and wait for all active readers and writers.
+    #
+    # @return [Boolean] true if the lock is successfully acquired
+    #
+    # @raise [Concurrent::ResourceLimitError] if the maximum number of writers
+    #   is exceeded.
+    def acquire_write_lock
+      if (held = @HeldCount.value) >= WRITE_LOCK_HELD
+        # if we already have a write (exclusive) lock, there's no need to wait
+        @HeldCount.value = held + WRITE_LOCK_HELD
+        return true
+      end
+
+      while true
+        c = @Counter.value
+        raise ResourceLimitError.new('Too many writer threads') if max_writers?(c)
+
+        # To go ahead and take the lock without waiting, there must be no writer
+        #   running right now, AND no writers who came before us still waiting to
+        #   acquire the lock
+        # Additionally, if any read locks have been taken, we must hold all of them
+        if held > 0 && @Counter.compare_and_set(1, c+RUNNING_WRITER)
+          # If we are the only one reader and successfully swap the RUNNING_WRITER bit on, then we can go ahead
+          @HeldCount.value = held + WRITE_LOCK_HELD
+          return true
+        elsif @Counter.compare_and_set(c, c+WAITING_WRITER)
+          while true
+            # Now we have successfully incremented, so no more readers will be able to increment
+            #   (they will wait instead)
+            # However, readers OR writers could decrement right here
+            @WriteQueue.synchronize do
+              # So we have to do another check inside the synchronized section
+              # If a writer OR another reader is running, then go to sleep
+              c = @Counter.value
+              @WriteQueue.ns_wait if running_writer?(c) || running_readers(c) != held
+            end
+            # Note: if you are thinking of replacing the above 'synchronize' block
+            # with #wait_until, read the comment in #acquire_read_lock first!
+
+            # We just came out of a wait
+            # If we successfully turn the RUNNING_WRITER bit on with an atomic swap,
+            #   then we are OK to stop waiting and go ahead
+            # Otherwise go back and wait again
+            c = @Counter.value
+            if !running_writer?(c) &&
+               running_readers(c) == held &&
+               @Counter.compare_and_set(c, c+RUNNING_WRITER-WAITING_WRITER)
+              @HeldCount.value = held + WRITE_LOCK_HELD
+              return true
+            end
+          end
+        end
+      end
+    end
+
+    # Try to acquire a write lock and return true if we succeed. If it cannot be
+    # acquired immediately, return false.
+    #
+    # @return [Boolean] true if the lock is successfully acquired
+    def try_write_lock
+      if (held = @HeldCount.value) >= WRITE_LOCK_HELD
+        @HeldCount.value = held + WRITE_LOCK_HELD
+        return true
+      else
+        c = @Counter.value
+        if !waiting_or_running_writer?(c) &&
+           running_readers(c) == held &&
+           @Counter.compare_and_set(c, c+RUNNING_WRITER)
+           @HeldCount.value = held + WRITE_LOCK_HELD
+          return true
+        end
+      end
+      false
+    end
+
+    # Release a previously acquired write lock.
+    #
+    # @return [Boolean] true if the lock is successfully released
+    def release_write_lock
+      held = @HeldCount.value = @HeldCount.value - WRITE_LOCK_HELD
+      wlocks_held = held & WRITE_LOCK_MASK
+      if wlocks_held == 0
+        c = @Counter.update { |counter| counter - RUNNING_WRITER }
+        @ReadQueue.broadcast
+        @WriteQueue.signal if waiting_writers(c) > 0
+      elsif wlocks_held == WRITE_LOCK_MASK
+        raise IllegalOperationError, "Cannot release a write lock which is not held"
+      end
+      true
+    end
+
+    private
+
+    # @!visibility private
+    def running_readers(c = @Counter.value)
+      c & MAX_READERS
+    end
+
+    # @!visibility private
+    def running_readers?(c = @Counter.value)
+      (c & MAX_READERS) > 0
+    end
+
+    # @!visibility private
+    def running_writer?(c = @Counter.value)
+      c >= RUNNING_WRITER
+    end
+
+    # @!visibility private
+    def waiting_writers(c = @Counter.value)
+      (c & MAX_WRITERS) >> READER_BITS
+    end
+
+    # @!visibility private
+    def waiting_or_running_writer?(c = @Counter.value)
+      c >= WAITING_WRITER
+    end
+
+    # @!visibility private
+    def max_readers?(c = @Counter.value)
+      (c & MAX_READERS) == MAX_READERS
+    end
+
+    # @!visibility private
+    def max_writers?(c = @Counter.value)
+      (c & MAX_WRITERS) == MAX_WRITERS
+    end
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/semaphore.rb

@@ -0,0 +1,163 @@
+require 'concurrent/atomic/mutex_semaphore'
+
+module Concurrent
+
+  ###################################################################
+
+  # @!macro semaphore_method_initialize
+  #
+  #   Create a new `Semaphore` with the initial `count`.
+  #
+  #   @param [Fixnum] count the initial count
+  #
+  #   @raise [ArgumentError] if `count` is not an integer
+
+  # @!macro semaphore_method_acquire
+  #
+  #   Acquires the given number of permits from this semaphore,
+  #     blocking until all are available. If a block is given,
+  #     yields to it and releases the permits afterwards.
+  #
+  #   @param [Fixnum] permits Number of permits to acquire
+  #
+  #   @raise [ArgumentError] if `permits` is not an integer or is less than zero
+  #
+  #   @return [nil, BasicObject] Without a block, `nil` is returned. If a block
+  #   is given, its return value is returned.
+
+  # @!macro semaphore_method_available_permits
+  #
+  #   Returns the current number of permits available in this semaphore.
+  #
+  #   @return [Integer]
+
+  # @!macro semaphore_method_drain_permits
+  #
+  #   Acquires and returns all permits that are immediately available.
+  #
+  #   @return [Integer]
+
+  # @!macro semaphore_method_try_acquire
+  #
+  #   Acquires the given number of permits from this semaphore,
+  #     only if all are available at the time of invocation or within
+  #     `timeout` interval. If a block is given, yields to it if the permits
+  #     were successfully acquired, and releases them afterward, returning the
+  #     block's return value.
+  #
+  #   @param [Fixnum] permits the number of permits to acquire
+  #
+  #   @param [Fixnum] timeout the number of seconds to wait for the counter
+  #     or `nil` to return immediately
+  #
+  #   @raise [ArgumentError] if `permits` is not an integer or is less than zero
+  #
+  #   @return [true, false, nil, BasicObject] `false` if no permits are
+  #     available, `true` when acquired a permit. If a block is given, the
+  #     block's return value is returned if the permits were acquired; if not,
+  #     `nil` is returned.
+
+  # @!macro semaphore_method_release
+  #
+  #   Releases the given number of permits, returning them to the semaphore.
+  #
+  #   @param [Fixnum] permits Number of permits to return to the semaphore.
+  #
+  #   @raise [ArgumentError] if `permits` is not a number or is less than zero
+  #
+  #   @return [nil]
+
+  ###################################################################
+
+  # @!macro semaphore_public_api
+  #
+  #   @!method initialize(count)
+  #     @!macro semaphore_method_initialize
+  #
+  #   @!method acquire(permits = 1)
+  #     @!macro semaphore_method_acquire
+  #
+  #   @!method available_permits
+  #     @!macro semaphore_method_available_permits
+  #
+  #   @!method drain_permits
+  #     @!macro semaphore_method_drain_permits
+  #
+  #   @!method try_acquire(permits = 1, timeout = nil)
+  #     @!macro semaphore_method_try_acquire
+  #
+  #   @!method release(permits = 1)
+  #     @!macro semaphore_method_release
+
+  ###################################################################
+
+  # @!visibility private
+  # @!macro internal_implementation_note
+  SemaphoreImplementation = if Concurrent.on_jruby?
+                              require 'concurrent/utility/native_extension_loader'
+                              JavaSemaphore
+                            else
+                              MutexSemaphore
+                            end
+  private_constant :SemaphoreImplementation
+
+  # @!macro semaphore
+  #
+  #   A counting semaphore. Conceptually, a semaphore maintains a set of
+  #   permits. Each {#acquire} blocks if necessary until a permit is
+  #   available, and then takes it. Each {#release} adds a permit, potentially
+  #   releasing a blocking acquirer.
+  #   However, no actual permit objects are used; the Semaphore just keeps a
+  #   count of the number available and acts accordingly.
+  #   Alternatively, permits may be acquired within a block, and automatically
+  #   released after the block finishes executing.
+  #
+  # @!macro semaphore_public_api
+  # @example
+  #   semaphore = Concurrent::Semaphore.new(2)
+  #
+  #   t1 = Thread.new do
+  #     semaphore.acquire
+  #     puts "Thread 1 acquired semaphore"
+  #   end
+  #
+  #   t2 = Thread.new do
+  #     semaphore.acquire
+  #     puts "Thread 2 acquired semaphore"
+  #   end
+  #
+  #   t3 = Thread.new do
+  #     semaphore.acquire
+  #     puts "Thread 3 acquired semaphore"
+  #   end
+  #
+  #   t4 = Thread.new do
+  #     sleep(2)
+  #     puts "Thread 4 releasing semaphore"
+  #     semaphore.release
+  #   end
+  #
+  #   [t1, t2, t3, t4].each(&:join)
+  #
+  #   # prints:
+  #   # Thread 3 acquired semaphore
+  #   # Thread 2 acquired semaphore
+  #   # Thread 4 releasing semaphore
+  #   # Thread 1 acquired semaphore
+  #
+  # @example
+  #   semaphore = Concurrent::Semaphore.new(1)
+  #
+  #   puts semaphore.available_permits
+  #   semaphore.acquire do
+  #     puts semaphore.available_permits
+  #   end
+  #   puts semaphore.available_permits
+  #
+  #   # prints:
+  #   # 1
+  #   # 0
+  #   # 1
+  class Semaphore < SemaphoreImplementation
+  end
+end

bin/gems/concurrent-ruby-1.3.5/lib/concurrent-ruby/concurrent/atomic/thread_local_var.rb

@@ -0,0 +1,111 @@
+require 'concurrent/constants'
+require_relative 'locals'
+
+module Concurrent
+
+  # A `ThreadLocalVar` is a variable where the value is different for each thread.
+  # Each variable may have a default value, but when you modify the variable only
+  # the current thread will ever see that change.
+  #
+  # This is similar to Ruby's built-in thread-local variables (`Thread#thread_variable_get`),
+  # but with these major advantages:
+  # * `ThreadLocalVar` has its own identity, it doesn't need a Symbol.
+  # * Each Ruby's built-in thread-local variable leaks some memory forever (it's a Symbol held forever on the thread),
+  #   so it's only OK to create a small amount of them.
+  #   `ThreadLocalVar` has no such issue and it is fine to create many of them.
+  # * Ruby's built-in thread-local variables leak forever the value set on each thread (unless set to nil explicitly).
+  #   `ThreadLocalVar` automatically removes the mapping for each thread once the `ThreadLocalVar` instance is GC'd.
+  #
+  # @!macro thread_safe_variable_comparison
+  #
+  # @example
+  #   v = ThreadLocalVar.new(14)
+  #   v.value #=> 14
+  #   v.value = 2
+  #   v.value #=> 2
+  #
+  # @example
+  #   v = ThreadLocalVar.new(14)
+  #
+  #   t1 = Thread.new do
+  #     v.value #=> 14
+  #     v.value = 1
+  #     v.value #=> 1
+  #   end
+  #
+  #   t2 = Thread.new do
+  #     v.value #=> 14
+  #     v.value = 2
+  #     v.value #=> 2
+  #   end
+  #
+  #   v.value #=> 14
+  class ThreadLocalVar
+    LOCALS = ThreadLocals.new
+
+    # Creates a thread local variable.
+    #
+    # @param [Object] default the default value when otherwise unset
+    # @param [Proc] default_block Optional block that gets called to obtain the
+    #   default value for each thread
+    def initialize(default = nil, &default_block)
+      if default && block_given?
+        raise ArgumentError, "Cannot use both value and block as default value"
+      end
+
+      if block_given?
+        @default_block = default_block
+        @default = nil
+      else
+        @default_block = nil
+        @default = default
+      end
+
+      @index = LOCALS.next_index(self)
+    end
+
+    # Returns the value in the current thread's copy of this thread-local variable.
+    #
+    # @return [Object] the current value
+    def value
+      LOCALS.fetch(@index) { default }
+    end
+
+    # Sets the current thread's copy of this thread-local variable to the specified value.
+    #
+    # @param [Object] value the value to set
+    # @return [Object] the new value
+    def value=(value)
+      LOCALS.set(@index, value)
+    end
+
+    # Bind the given value to thread local storage during
+    # execution of the given block.
+    #
+    # @param [Object] value the value to bind
+    # @yield the operation to be performed with the bound variable
+    # @return [Object] the value
+    def bind(value)
+      if block_given?
+        old_value = self.value
+        self.value = value
+        begin
+          yield
+        ensure
+          self.value = old_value
+        end
+      end
+    end
+
+    protected
+
+    # @!visibility private
+    def default
+      if @default_block
+        self.value = @default_block.call
+      else
+        @default
+      end
+    end
+  end
+end