* lib/generator.rb: uses Mutex instead of Thread.critical.

[ruby-dev:28184]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@9773 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Fri Dec 30 18:27:00 2005  Hirokazu Yamamoto  <ocean@m2.ccsnet.ne.jp>
+
+	* lib/generator.rb: uses Mutex instead of Thread.critical.
+	  [ruby-dev:28184]
+
 Fri Dec 30 18:22:42 2005  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* gc.c (garbage_collect): mark objects refered from aborting threads.

lib/generator.rb

@@ -23,6 +23,7 @@
 #
 # See the respective classes for examples of usage.
 
+require "thread"
 
 #
 # Generator converts an internal iterator (i.e. an Enumerable object)
@@ -71,17 +72,24 @@ class Generator
     end
     @index = 0
     @queue = []
+    @mutex = Mutex.new
+    @main_cond = ConditionVariable.new
+    @loop_cond = ConditionVariable.new
+    entered = false
     @loop_thread = Thread.new do
-      Thread.stop
+      @mutex.synchronize do
-      begin
+        entered = true
-        @block.call(self)
+        @loop_cond.wait(@mutex)
-      rescue
+        begin
-        @main_thread.raise
+          @block.call(self)
-      ensure
+        rescue
-        @main_thread.wakeup
+          @main_thread.raise $!
+        ensure
+          @main_cond.signal
+        end
       end
     end
-    Thread.pass until @loop_thread.stop?
+    Thread.pass until entered && !@mutex.locked?
     self
   end
 
@@ -90,33 +98,26 @@ class Generator
     if Thread.current != @loop_thread
       raise "should be called in Generator.new{|g| ... }"
     end
-    Thread.critical = true
+    @queue << value
-    begin
+    @main_cond.signal
-      @queue << value
+    @loop_cond.wait(@mutex)
-      @main_thread.wakeup
-      Thread.stop
-    ensure
-      Thread.critical = false
-    end
     self
   end
 
   # Returns true if the generator has reached the end.
   def end?
-    if @queue.empty?
+    @mutex.synchronize do
-      if @main_thread
+      if @queue.empty? && @loop_thread.alive?
-        raise "should not be called in Generator.new{|g| ... }"
+        if @main_thread
-      end
+          raise "should not be called in Generator.new{|g| ... }"
-      Thread.critical = true
+        end
-      begin
+        begin
-        @main_thread = Thread.current
+          @main_thread = Thread.current
-        @loop_thread.wakeup
+          @loop_cond.signal
-        Thread.stop
+          @main_cond.wait(@mutex)
-      rescue ThreadError
+        ensure
-        # ignore
+          @main_thread = nil
-      ensure
+        end
-        @main_thread = nil
-        Thread.critical = false
       end
     end
     @queue.empty?