Introducing remoting::Stoppable helper base class implementing asynchronous shutdown on a specific t

remoting/base/shutdownable.cc

Index: remoting/base/shutdownable.cc
diff --git a/remoting/base/shutdownable.cc b/remoting/base/shutdownable.cc
new file mode 100644
index 0000000000000000000000000000000000000000..14babbb2c8b23ad56386a3e220bc698cfb29186e
--- /dev/null
+++ b/remoting/base/shutdownable.cc
@@ -0,0 +1,47 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "remoting/base/shutdownable.h"
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/message_loop.h"
+#include "base/single_thread_task_runner.h"
+
+namespace remoting {
+
+Shutdownable::Shutdownable(
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+    const Callback& done)
+    : task_runner_(task_runner),
+      done_(done),
+      state_(kRunning) {
+}
+
+Shutdownable::~Shutdownable() {
+  DCHECK_EQ(state_, kStopped);
+}
+
+void Shutdownable::Shutdown() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+
+  if (state_ == kRunning) {
+    state_ = kShutdown;
+    DoShutdown();
+  }
+}
+
+void Shutdownable::CompleteShutdown() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  DCHECK_EQ(state_, kShutdown);
+
+  state_ = kStopped;
+  task_runner_->PostTask(FROM_HERE, base::Bind(done_, this));
+}
+
+void Shutdownable::DoShutdown() {
+  CompleteShutdown();
+}
+
+}  // namespace remoting