selector.rb in agent-0.9.1

- old
+ new

@@ -9,15 +9,10 @@
   def self.select!
     raise Errors::BlockMissing unless block_given?
     selector = Selector.new
     yield selector
     selector.select
-  ensure
-    if selector
-      selector.close_default_channel
-      selector.dequeue_operations
-    end
   end
 
   class Selector
     attr_reader :cases
 
@@ -27,10 +22,12 @@
       @ordered_cases = []
       @cases         = {}
       @operations    = {}
       @blocking_once = BlockingOnce.new
       @notifier      = Notifier.new
+      @default_case  = nil
+      @selected      = false
     end
 
     def default(&blk)
       if @default_case
         raise Errors::DefaultCaseAlreadyDefinedError
@@ -45,16 +42,17 @@
       add_case(s, :timeout, &blk)
     end
 
     def case(chan, direction, value=nil, &blk)
       raise "invalid case, must be a channel" unless chan.is_a?(Channel)
-      raise Errors::BlockMissing if blk.nil? && direction == :receive
       raise Errors::InvalidDirection if direction != :send && direction != :receive
       add_case(chan, direction, value, &blk)
     end
 
     def select
+      raise Errors::AlreadySelectedError if @selected
+
       if !@ordered_cases.empty?
         @ordered_cases.each do |cse|
           if cse.direction == :send
             @operations[cse.channel] << cse.channel.send(cse.value, :uuid => cse.uuid,
                                                                     :blocking_once => @blocking_once,
@@ -74,23 +72,27 @@
 
         @notifier.wait
 
         execute_case(@notifier.payload)
       end
+    ensure
+      @selected = true
+      close_default_channel
+      dequeue_operations
     end
 
+
+  protected
+
     def dequeue_operations
       @operations.each do |channel, operations|
         channel.remove_operations(operations)
       end
     end
 
     def close_default_channel
       @default_case.channel.close if @default_case
     end
-
-
-  protected
 
     def add_case(chan, direction, value=nil, &blk)
       uuid = UUID.generate
       cse = Case.new(uuid, chan, direction, value, blk)
       @ordered_cases << cse