allow Queue operation in trap.

* thread_sync.c: allow spurious wakeup to check Queue status just after trap.
  [Bug #12405]

* test/thread/test_queue.rb: add a test for it.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57479 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/thread/test_queue.rb

@@ -547,4 +547,21 @@ class TestQueue < Test::Unit::TestCase
     # don't leak this thread
     assert_nothing_raised{counter.join}
   end
+
+  def test_queue_with_trap
+    assert_in_out_err([], <<-INPUT, %w(USR2 USR2 exit), [])
+      q = Queue.new
+      trap(:USR2){
+        q.push 'USR2'
+      }
+      Thread.new{
+        loop{
+          Process.kill :USR2, $$
+        }
+      }
+      puts q.pop
+      puts q.pop
+      puts 'exit'
+    INPUT
+  end
 end

thread_sync.c

@@ -773,7 +773,7 @@ queue_delete_from_waiting(struct waiting_delete *p)
 static VALUE
 queue_sleep(VALUE arg)
 {
-    rb_thread_sleep_deadly();
+    rb_thread_sleep_deadly_allow_spurious_wakeup();
     return Qnil;
 }