import from drb-2.0.4b3

git-svn-id: http://svn.ruby-lang.org/repos/ruby/trunk@3959 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 94 insertions, 0 deletions

diff --git a/lib/drb/extservm.rb b/lib/drb/extservm.rb
new file mode 100644
index 000000000..50009dbae
--- /dev/null
+++ b/lib/drb/extservm.rb
@@ -0,0 +1,94 @@
+=begin
+ external service manager
+ 	Copyright (c) 2000 Masatoshi SEKI 
+=end
+
+require 'drb/drb'
+require 'thread'
+
+module DRb
+  class ExtServManager
+    include DRbUndumped
+
+    @@command = {}
+
+    def self.command
+      @@command
+    end
+
+    def self.command=(cmd)
+      @@command = cmd
+    end
+      
+    def initialize
+      @servers = {}
+      @waiting = []
+      @queue = Queue.new
+      @thread = invoke_thread
+    end
+    attr_reader :server
+
+    def service(name)
+      while true
+	server = nil
+	Thread.exclusive do
+	  server = @servers[name] if @servers[name]
+	end
+	return server if server && server.alive?
+	invoke_service(name)
+      end
+    end
+
+    def regist(name, ro)
+      ary = nil
+      Thread.exclusive do
+	@servers[name] = ro
+	ary = @waiting
+	@waiting = []
+      end
+      ary.each do |th|
+	begin
+	  th.run
+	rescue ThreadError
+	end
+      end
+      self
+    end
+    
+    def unregist(name)
+      Thread.exclusive do
+	@servers.delete(name)
+      end
+    end
+
+    private
+    def invoke_thread
+      Thread.new do
+	while true
+	  name = @queue.pop
+	  invoke_service_command(name, @@command[name])
+	end
+      end
+    end
+
+    def invoke_service(name)
+      Thread.critical = true
+      @waiting.push Thread.current
+      @queue.push name
+      Thread.stop
+    end
+
+    def invoke_service_command(name, command)
+      raise "invalid command. name: #{name}" unless command
+      Thread.exclusive do
+	return if @servers.include?(name)
+	@servers[name] = false
+      end
+      if RUBY_PLATFORM =~ /mswin32/
+	system("cmd /c start /b #{command} #{DRb.uri} #{name}")
+      else
+	system("#{command} #{DRb.uri} #{name} &")
+      end
+    end
+  end
+end