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

remoting/base/stoppable.cc

+// 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/stoppable.h"
+
+#include "base/message_loop.h"
+#include "base/single_thread_task_runner.h"
+
+namespace remoting {
+
+Stoppable::Stoppable(
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+    const base::Closure& stopped_callback)
+    : state_(kRunning),
+      stopped_callback_(stopped_callback),
+      task_runner_(task_runner) {
+}
+
+Stoppable::~Stoppable() {
+  DCHECK_EQ(state_, kStopped);
+}
+
+void Stoppable::Stop() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+
+  if (state_ == kRunning) {
+    state_ = kStopping;
+    DoStop();
+  }
+}
+
+void Stoppable::CompleteStopping() {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+  DCHECK_EQ(state_, kStopping);
+
+  state_ = kStopped;
+  task_runner_->PostTask(FROM_HERE, stopped_callback_);
+}
+
+}  // namespace remoting