Added fixed gateway script [Nicholas Seckar]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@1721 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 54 insertions, 95 deletions

diff --git a/railties/bin/tracker b/railties/bin/tracker
index 17fce67e54..859c9fa0e0 100644
--- a/railties/bin/tracker
+++ b/railties/bin/tracker
@@ -1,110 +1,69 @@
-require "drb"
-require "rbconfig"
+#!/usr/local/bin/ruby
 
-VERBOSE = false
+require 'drb'
+require 'thread'
+
+def message(s)
+  $stderr.puts "tracker: #{s}" if ENV && ENV["DEBUG_GATEWAY"]
+end
 
 class Tracker
   include DRbUndumped
-  
-  def initialize(timeout = 90, uri = nil)
-    @timeout = timeout
-    @waiting = []
-    @working = []
-    
-    @waiting_mutex = Mutex.new
-    
-    DRb.start_service(uri, self)
-    @uri = DRb.uri
-  end
-  def run
-    start_listener 3
-    sleep 3
-    
-    background
-  end
-  
-  def register_listener(listener)
-    @waiting.push listener
-    nil
-  end
-  def remove_listener(listener)
-    @waiting.delete listener
-    @working.delete listener
-    nil
+
+  def initialize(instances, socket_path)
+    @instances = instances
+    @socket = File.expand_path(socket_path)
+    @active = false
+
+    @listeners = []
+    @instances.times { @listeners << Mutex.new }
+
+    message "using #{@listeners.length} listeners"
+    message "opening socket at #{@socket}"
+
+    @service = DRb.start_service("drbunix://#{@socket}", self)
   end
-  
+
   def with_listener
-    listener = @waiting.shift
-    unless listener
-      start_listener(2) unless @waiting.length + @working.length > 6
-      @waiting_mutex.synchronize do
-	10.times do
-          sleep 0.5
-          listener = @waiting.shift
-          break if listener
-        end
-        unless listener
-          ($stderr.puts "Dropping request due to lack of listeners!!!" unless listener) if VERBOSE
-          return
-        end
+    message "listener requested"
+
+    mutex = has_lock = index = nil
+    3.times do 
+      @listeners.each_with_index do |mutex, index|
+        has_lock = mutex.try_lock
+        break if has_lock
       end
+      break if has_lock
+      sleep 0.05
     end
-    
-    @working << listener
-    yield listener
-  ensure
-    if listener
-      @working.delete listener
-      @waiting << listener
-    end
-  end
-  
-  def background
-    loop do
-      @timeout ? sleep(@timeout) : sleep
-      unless @processed
-        $stderr.puts "Idle for #{@timeout} -- shutting down tracker." if VERBOSE
-        Kernel.exit 0 
+
+    if has_lock
+      message "obtained listener #{index}"
+      @active = true
+      begin yield index
+      ensure
+        mutex.unlock
+        message "released listener #{index}"
       end
-      @processed = false
+    else
+      message "dropping request because no listeners are available!"
     end
   end
-    
-  def process(input)
-    output = nil
-    $stderr.puts "tracker: received request.. obtaining listener" if VERBOSE
-    with_listener do |listener|
-      $stderr.puts "tracker: obtained -- forwarding request to listener.." if VERBOSE
-      @processed = true
-      output = listener.process(input)
-      $stderr.puts "tracker: listener released control." if VERBOSE
-    end
-    return output
-  end
-  
-  def start_listener(n = 1)
-    tracker_uri = @uri
-    listener_path = File.join(File.dirname(__FILE__), 'listener')
-    fork do
-      exec(
-        File.join(Config::CONFIG['bin_dir'], Config::CONFIG['RUBY_SO_NAME']), 
-        listener_path, 'start-listeners', tracker_uri, n.to_s
-      )
+
+  def background(check_interval = nil)
+    if check_interval
+      loop do
+        sleep check_interval
+        message "Idle for #{check_interval}, shutting down" unless @active
+        @active = false
+        Kernel.exit 0
+      end
+    else DRb.thread.join
     end
   end
-  
-  def ping
-    true
-  end
 end
 
-if ARGV.first == "start"
-  tracker = Tracker.new(90, ARGV[1])
-  socket = (/druby:([^?]*)\?/ =~ ARGV[1]) ? $1 : nil
-  require 'fileutils' if socket
-
-  begin tracker.run
-  ensure 
-    FileUtils.rm_f(socket) if socket
-  end
-end
+socket_path = ARGV.shift
+instances = ARGV.shift.to_i
+t = Tracker.new(instances, socket_path)
+t.background(ARGV.first ? ARGV.shift.to_i : 90)
\ No newline at end of file