c – 刷新boost :: asio中的所有异步处理程序

virtual void SetUp()
{
  _client = new Client;
  _server = new Server;

  Service::run();
}

virtual void TearDown()
{
  Service::stop();

  delete _client;
  delete _server;
}

static void run()
{
  _thread = new asio::thread(boost::bind(&asio::io_service::run,_service));
}

static void stop()
{
  _service->stop();

  _thread->join();
  delete _thread;

  _service->reset();
}

在我看来,你需要稍微重新考虑你的设计.正如你所注意到的那样,io_service :: stop确实是异步的.它会导致io_service :: run()的任何调用尽快返回.在~io_service()析构函数运行之前,不会使用boost :: asio :: error :: operation_aborted调用任何未完成的处理程序.要管理对象生存期,您应该使用shared_ptr,如 documentation所示：

The destruction sequence described
above permits programs to simplify
their resource management by using
shared_ptr<>. Where an object’s
lifetime is tied to the lifetime of a
connection (or some other sequence of
asynchronous operations),a shared_ptr
to the object would be bound into the
handlers for all asynchronous
operations associated with it. This
works as follows:

• When a single connection ends,all associated asynchronous operations
  complete. The corresponding handler
  objects are destroyed,and all
  shared_ptr references to the objects
  are destroyed.
• To shut down the whole program,the io_service function stop() is called
  to terminate any run() calls as soon
  as possible. The io_service destructor
  defined above destroys all handlers,
  causing all shared_ptr references to
  all connection objects to be
  destroyed.

更具体地说,你有一个竞争条件

virtual void TearDown()
{
  service->stop();

  // ok,io_service is no longer running
  // what if outstanding handlers use _client or _server ??

  delete _client;
  delete _server;

  // now you have undefined behavior due to a dangling pointer
}