Merge pull request #462 from ruby-concurrency/sync-updates

Sync updates

Author: jdantonio

examples/go-by-example-channels/non-blocking-channel-operations.rb

@@ -15,9 +15,9 @@
   s.default { print "no message received\n" }
 end
 
-msg = 'hi'
+message = 'hi'
 Channel.select do |s|
-  s.put(messages, msg) { |m| print "sent message #{m}\n" }
+  s.put(messages, message) { |msg| print "sent message #{msg}\n" }
   s.default { print "no message sent\n" }
 end
 

lib/concurrent/channel/tick.rb

@@ -1,3 +1,4 @@
+require 'concurrent/synchronization'
 require 'concurrent/utility/monotonic_time'
 
 module Concurrent
@@ -13,8 +14,9 @@ class Channel
     # @see Concurrent.monotonic_time
     # @see Concurrent::Channel.ticker
     # @see Concurrent::Channel.timer
-    class Tick
+    class Tick < Synchronization::Object
       include Comparable
+      safe_initialization!
 
       STRING_FORMAT = '%F %T.%6N %z %Z'.freeze
 

lib/concurrent/concern/dereferenceable.rb

@@ -9,13 +9,17 @@ module Concern
     #
     # @!macro copy_options
     module Dereferenceable
+      # NOTE: This module is going away in 2.0. In the mean time we need it to
+      # play nicely with the synchronization layer. This means that the
+      # including class SHOULD be synchronized and it MUST implement a
+      # `#synchronize` method. Not doing so will lead to runtime errors.
 
       # Return the value this object represents after applying the options specified
       # by the `#set_deref_options` method.
       #
       # @return [Object] the current value of the object
       def value
-        mutex.synchronize { apply_deref_options(@value) }
+        synchronize { apply_deref_options(@value) }
       end
       alias_method :deref, :value
 
@@ -25,43 +29,24 @@ def value
       #
       # @param [Object] value the new value
       def value=(value)
-        mutex.synchronize{ @value = value }
-      end
-
-      # A mutex lock used for synchronizing thread-safe operations. Methods defined
-      # by `Dereferenceable` are synchronized using the `Mutex` returned from this
-      # method. Operations performed by the including class that operate on the
-      # `@value` instance variable should be locked with this `Mutex`.
-      #
-      # @return [Mutex] the synchronization object
-      def mutex
-        @mutex
-      end
-
-      # Initializes the internal `Mutex`.
-      #
-      # @note This method *must* be called from within the constructor of the including class.
-      #
-      # @see #mutex
-      def init_mutex(mutex = Mutex.new)
-        @mutex = mutex
+        synchronize{ @value = value }
       end
 
       # @!macro [attach] dereferenceable_set_deref_options
       #   Set the options which define the operations #value performs before
       #   returning data to the caller (dereferencing).
-      #  
+      #
       #   @note Most classes that include this module will call `#set_deref_options`
       #   from within the constructor, thus allowing these options to be set at
       #   object creation.
-      #  
+      #
       #   @param [Hash] opts the options defining dereference behavior.
       #   @option opts [String] :dup_on_deref (false) call `#dup` before returning the data
       #   @option opts [String] :freeze_on_deref (false) call `#freeze` before returning the data
       #   @option opts [String] :copy_on_deref (nil) call the given `Proc` passing
       #     the internal value and returning the value returned from the proc
       def set_deref_options(opts = {})
-        mutex.synchronize{ ns_set_deref_options(opts) }
+        synchronize{ ns_set_deref_options(opts) }
       end
 
       # @!macro dereferenceable_set_deref_options

lib/concurrent/concern/obligation.rb

@@ -9,6 +9,10 @@ module Concern
 
     module Obligation
       include Concern::Dereferenceable
+      # NOTE: The Dereferenceable module is going away in 2.0. In the mean time
+      # we need it to place nicely with the synchronization layer. This means
+      # that the including class SHOULD be synchronized and it MUST implement a
+      # `#synchronize` method. Not doing so will lead to runtime errors.
 
       # Has the obligation been fulfilled?
       #
@@ -104,7 +108,7 @@ def value!(timeout = nil)
       #
       # @return [Symbol] the current state
       def state
-        mutex.synchronize { @state }
+        synchronize { @state }
       end
 
       # If an exception was raised during processing this will return the
@@ -113,7 +117,7 @@ def state
       #
       # @return [Exception] the exception raised during processing or `nil`
       def reason
-        mutex.synchronize { @reason }
+        synchronize { @reason }
       end
 
       # @example allows Obligation to be risen
@@ -132,8 +136,7 @@ def get_arguments_from(opts = {})
       end
 
       # @!visibility private
-      def init_obligation(*args)
-        init_mutex(*args)
+      def init_obligation
         @event = Event.new
       end
 
@@ -155,20 +158,20 @@ def set_state(success, value, reason)
 
       # @!visibility private
       def state=(value)
-        mutex.synchronize { ns_set_state(value) }
+        synchronize { ns_set_state(value) }
       end
 
       # Atomic compare and set operation
       # State is set to `next_state` only if `current state == expected_current`.
       #
       # @param [Symbol] next_state
       # @param [Symbol] expected_current
-      # 
+      #
       # @return [Boolean] true is state is changed, false otherwise
       #
       # @!visibility private
       def compare_and_set_state(next_state, *expected_current)
-        mutex.synchronize do
+        synchronize do
           if expected_current.include? @state
             @state = next_state
             true
@@ -184,7 +187,7 @@ def compare_and_set_state(next_state, *expected_current)
       #
       # @!visibility private
       def if_state(*expected_states)
-        mutex.synchronize do
+        synchronize do
           raise ArgumentError.new('no block given') unless block_given?
 
           if expected_states.include? @state

lib/concurrent/delay.rb

@@ -155,7 +155,7 @@ def reconfigure(&block)
     protected
 
     def ns_initialize(opts, &block)
-      init_obligation(self)
+      init_obligation
       set_deref_options(opts)
       @executor = opts[:executor]
 

lib/concurrent/edge/future.rb

@@ -131,7 +131,7 @@ def post_on(executor, *args, &job)
     # Represents an event which will happen in future (will be completed). It has to always happen.
     class Event < Synchronization::LockableObject
       safe_initialization!
-      private *attr_volatile_with_cas(:internal_state)
+      private(*attr_volatile_with_cas(:internal_state))
       public :internal_state
       include Concern::Deprecation
       include Concern::Logging

lib/concurrent/ivar.rb

@@ -153,7 +153,7 @@ def try_set(value = NULL, &block)
     # @!visibility private
     def ns_initialize(value, opts)
       value = yield if block_given?
-      init_obligation(self)
+      init_obligation
       self.observers = Collection::CopyOnWriteObserverSet.new
       set_deref_options(opts)
 

lib/concurrent/lazy_register.rb

@@ -18,7 +18,7 @@ module Concurrent
   # @!macro edge_warning
   class LazyRegister < Synchronization::Object
 
-    private *attr_volatile_with_cas(:data)
+    private(*attr_volatile_with_cas(:data))
 
     def initialize
       super

lib/concurrent/maybe.rb

@@ -1,3 +1,5 @@
+require 'concurrent/synchronization'
+
 module Concurrent
 
   # A `Maybe` encapsulates an optional value. A `Maybe` either contains a value
@@ -99,8 +101,9 @@ module Concurrent
   #
   # @see https://hackage.haskell.org/package/base-4.2.0.1/docs/Data-Maybe.html Haskell Data.Maybe
   # @see https://github.com/purescript/purescript-maybe/blob/master/docs/Data.Maybe.md PureScript Data.Maybe
-  class Maybe
+  class Maybe < Synchronization::Object
     include Comparable
+    safe_initialization!
 
     # Indicates that the given attribute has not been set.
     # When `Just` the {#nothing} getter will return `NONE`.
@@ -168,15 +171,15 @@ def self.nothing(error = '')
     end
 
     # Is this `Maybe` a `Just` (successfully fulfilled with a value)?
-    # 
+    #
     # @return [Boolean] True if `Just` or false if `Nothing`.
     def just?
       ! nothing?
     end
     alias :fulfilled? :just?
 
     # Is this `Maybe` a `nothing` (rejected with an exception upon fulfillment)?
-    # 
+    #
     # @return [Boolean] True if `Nothing` or false if `Just`.
     def nothing?
       @nothing != NONE

lib/concurrent/mvar.rb

@@ -1,4 +1,5 @@
 require 'concurrent/concern/dereferenceable'
+require 'concurrent/synchronization'
 
 module Concurrent
 
@@ -34,9 +35,9 @@ module Concurrent
   # 2. S. Peyton Jones, A. Gordon, and S. Finne. [Concurrent Haskell](http://dl.acm.org/citation.cfm?id=237794).
   #    In Proceedings of the 23rd Symposium on Principles of Programming Languages
   #    (PoPL), 1996.
-  class MVar
-
+  class MVar < Synchronization::Object
     include Concern::Dereferenceable
+    safe_initialization!
 
     # Unique value that represents that an `MVar` was empty
     EMPTY = Object.new
@@ -200,6 +201,12 @@ def full?
       !empty?
     end
 
+    protected
+
+    def synchronize(&block)
+      @mutex.synchronize(&block)
+    end
+
     private
 
     def unlocked_empty?