* ext/thread/thread.c (rb_queue_pop, rb_queue_push): should not lock

mutex if got an exception while waiting, and should ensure unlocked
  after signaled.  [ruby-dev:37545]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@22011 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Tue Feb  3 18:35:48 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* ext/thread/thread.c (rb_queue_pop, rb_queue_push): should not lock
+	  mutex if got an exception while waiting, and should ensure unlocked
+	  after signaled.  [ruby-dev:37545]
+
 Tue Feb  3 12:27:19 2009  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* re.c (match_check): check if MatchData is initialized.

ext/thread/thread.c

@@ -439,6 +439,12 @@ lock_mutex(Mutex *mutex)
     return Qnil;
 }
 
+static VALUE
+lock_mutex_call(VALUE mutex)
+{
+    return lock_mutex((Mutex *)mutex);
+}
+
 static VALUE
 rb_mutex_lock(VALUE self)
 {
@@ -491,6 +497,12 @@ unlock_mutex(Mutex *mutex)
     return Qtrue;
 }
 
+static VALUE
+unlock_mutex_call(VALUE mutex)
+{
+    return unlock_mutex((Mutex *)mutex);
+}
+
 static VALUE
 rb_mutex_unlock(VALUE self)
 {
@@ -644,8 +656,17 @@ rb_condvar_alloc(VALUE klass)
  *
  */
 
+static void condvar_wakeup(Mutex *mutex);
+
 static void
 wait_condvar(ConditionVariable *condvar, Mutex *mutex)
+{
+    condvar_wakeup(mutex);
+    rb_ensure(wait_list, (VALUE)&condvar->waiting, lock_mutex_call, (VALUE)mutex);
+}
+
+static void
+condvar_wakeup(Mutex *mutex)
 {
     VALUE waking;
 
@@ -658,7 +679,6 @@ wait_condvar(ConditionVariable *condvar, Mutex *mutex)
     if (RTEST(waking)) {
 	wake_thread(waking);
     }
-    rb_ensure(wait_list, (VALUE)&condvar->waiting, lock_mutex, (VALUE)mutex);
 }
 
 static VALUE
@@ -740,6 +760,13 @@ signal_condvar(ConditionVariable *condvar)
     }
 }
 
+static VALUE
+signal_condvar_call(VALUE condvar)
+{
+    signal_condvar((ConditionVariable *)condvar);
+    return Qundef;
+}
+
 static VALUE
 rb_condvar_signal(VALUE self)
 {
@@ -964,6 +991,16 @@ rb_queue_num_waiting(VALUE self)
     return result;
 }
 
+static void
+wait_queue(ConditionVariable *condvar, Mutex *mutex)
+{
+    condvar_wakeup(mutex);
+    wait_list(&condvar->waiting);
+    lock_mutex(mutex);
+}
+
+static VALUE queue_pop_inner(VALUE arg);
+
 /*
  * Document-method: pop
  * call_seq: pop(non_block=false)
@@ -979,7 +1016,6 @@ rb_queue_pop(int argc, VALUE *argv, VALUE self)
 {
     Queue *queue;
     int should_block;
-    VALUE result;
     Data_Get_Struct(self, Queue, queue);
 
     if (argc == 0) {
@@ -997,15 +1033,21 @@ rb_queue_pop(int argc, VALUE *argv, VALUE self)
     }
 
     while (!queue->values.entries) {
-        wait_condvar(&queue->value_available, &queue->mutex);
+        wait_queue(&queue->value_available, &queue->mutex);
     }
 
-    result = shift_list(&queue->values);
+    return rb_ensure(queue_pop_inner, (VALUE)queue,
+		     unlock_mutex_call, (VALUE)&queue->mutex);
+}
+
+static VALUE
+queue_pop_inner(VALUE arg)
+{
+    Queue *queue = (Queue *)arg;
+    VALUE result = shift_list(&queue->values);
     if (queue->capacity && queue->values.size < queue->capacity) {
         signal_condvar(&queue->space_available);
     }
-    unlock_mutex(&queue->mutex);
-
     return result;
 }
 
@@ -1025,11 +1067,11 @@ rb_queue_push(VALUE self, VALUE value)
 
     lock_mutex(&queue->mutex);
     while (queue->capacity && queue->values.size >= queue->capacity) {
-        wait_condvar(&queue->space_available, &queue->mutex);
+        wait_queue(&queue->space_available, &queue->mutex);
     }
     push_list(&queue->values, value);
-    signal_condvar(&queue->value_available);
+    rb_ensure(signal_condvar_call, (VALUE)&queue->value_available,
-    unlock_mutex(&queue->mutex);
+	      unlock_mutex_call, (VALUE)&queue->mutex);
 
     return self;
 }

test/thread/test_thread.rb

@@ -77,5 +77,14 @@ class TC_Thread < Test::Unit::TestCase
             assert_equal("exit.", result[/.*\Z/], '[ruby-dev:30653]')
         }
     end
+
+    def test_queue_rescue
+        require "timeout"
+        queue = Queue.new
+        assert_raises(Timeout::Error) {Timeout.timeout(0.001) {queue.pop}}
+        queue.push(1)
+        assert_nothing_raised("[ruby-dev:37545]") {assert_equal(1, queue.pop)}
+        assert(queue.empty?)
+    end
 end