Add bin and edit workflow

bin/gems/eventmachine-1.2.7/lib/em/queue.rb

@@ -0,0 +1,80 @@
+module EventMachine
+  # A cross thread, reactor scheduled, linear queue.
+  #
+  # This class provides a simple queue abstraction on top of the reactor
+  # scheduler. It services two primary purposes:
+  #
+  # * API sugar for stateful protocols
+  # * Pushing processing onto the reactor thread
+  #
+  # @example
+  #
+  #  q = EM::Queue.new
+  #  q.push('one', 'two', 'three')
+  #  3.times do
+  #    q.pop { |msg| puts(msg) }
+  #  end
+  #
+  class Queue
+    def initialize
+      @sink  = []
+      @drain = []
+      @popq  = []
+    end
+
+    # Pop items off the queue, running the block on the reactor thread. The pop
+    # will not happen immediately, but at some point in the future, either in
+    # the next tick, if the queue has data, or when the queue is populated.
+    #
+    # @return [NilClass] nil
+    def pop(*a, &b)
+      cb = EM::Callback(*a, &b)
+      EM.schedule do
+        if @drain.empty?
+          @drain = @sink
+          @sink = []
+        end
+        if @drain.empty?
+          @popq << cb
+        else
+          cb.call @drain.shift
+        end
+      end
+      nil # Always returns nil
+    end
+
+    # Push items onto the queue in the reactor thread. The items will not appear
+    # in the queue immediately, but will be scheduled for addition during the
+    # next reactor tick.
+    def push(*items)
+      EM.schedule do
+        @sink.push(*items)
+        unless @popq.empty?
+          @drain = @sink
+          @sink = []
+          @popq.shift.call @drain.shift until @drain.empty? || @popq.empty?
+        end
+      end
+    end
+    alias :<< :push
+
+    # @return [Boolean]
+    # @note This is a peek, it's not thread safe, and may only tend toward accuracy.
+    def empty?
+      @drain.empty? && @sink.empty?
+    end
+
+    # @return [Integer] Queue size
+    # @note This is a peek, it's not thread safe, and may only tend toward accuracy.
+    def size
+      @drain.size + @sink.size
+    end
+
+    # @return [Integer] Waiting size
+    # @note This is a peek at the number of jobs that are currently waiting on the Queue
+    def num_waiting
+      @popq.size
+    end
+
+  end # Queue
+end # EventMachine