Add MutexLocker and MonitorLocker to platform/bin

runtime/bin/thread.h

+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+#ifndef BIN_THREAD_H_
+#define BIN_THREAD_H_
+
+#include "platform/assert.h"
+#include "platform/thread.h"
+
+class MutexLocker  {
+ public:
+  explicit MutexLocker(dart::Mutex* mutex) : mutex_(mutex) {
+    ASSERT(mutex != NULL);
+    mutex_->Lock();
+  }
+
+  virtual ~MutexLocker() {
+    mutex_->Unlock();
+  }
+
+ private:
+  dart::Mutex* const mutex_;
+
+  DISALLOW_COPY_AND_ASSIGN(MutexLocker);
+};
+
+
+class MonitorLocker {
+ public:
+  explicit MonitorLocker(dart::Monitor* monitor) : monitor_(monitor) {
+    ASSERT(monitor != NULL);
+    monitor_->Enter();
+  }
+
+  virtual ~MonitorLocker() {
+    monitor_->Exit();
+  }
+
+  dart::Monitor::WaitResult Wait(int64_t millis = dart::Monitor::kNoTimeout) {
+    return monitor_->Wait(millis);
+  }
+
+  void Notify() {
+    monitor_->Notify();
+  }
+
+  void NotifyAll() {
+    monitor_->NotifyAll();
+  }
+
+ private:
+  dart::Monitor* const monitor_;
+
+  DISALLOW_COPY_AND_ASSIGN(MonitorLocker);
+};
+
+#endif  // BIN_THREAD_H_