net/base/test_completion_callback.h

// Copyright (c) 2006-2008 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.

#ifndef NET_BASE_TEST_COMPLETION_CALLBACK_H_
#define NET_BASE_TEST_COMPLETION_CALLBACK_H_

#include "base/message_loop.h"
#include "net/base/completion_callback.h"
#include "net/base/net_errors.h"

//-----------------------------------------------------------------------------
// completion callback helper

// A helper class for completion callbacks, designed to make it easy to run
// tests involving asynchronous operations.  Just call WaitForResult to wait
// for the asynchronous operation to complete.
//
// NOTE: Since this runs a message loop to wait for the completion callback,
// there could be other side-effects resulting from WaitForResult.  For this
// reason, this class is probably not ideal for a general application.
//
class TestCompletionCallback : public CallbackRunner< Tuple1<int> > {
 public:
  TestCompletionCallback()
      : result_(0),
        have_result_(false),
        waiting_for_result_(false) {
  }

  int WaitForResult() {
    DCHECK(!waiting_for_result_);
    while (!have_result_) {
      waiting_for_result_ = true;
      MessageLoop::current()->Run();
      waiting_for_result_ = false;
    }
    have_result_ = false;  // auto-reset for next callback
    return result_;
  }

  int GetResult(int result) {
    if (net::ERR_IO_PENDING != result)
      return result;
    return WaitForResult();
  }

  bool have_result() const { return have_result_; }

  virtual void RunWithParams(const Tuple1<int>& params) {
    result_ = params.a;
    have_result_ = true;
    if (waiting_for_result_)
      MessageLoop::current()->Quit();
  }

 private:
  int result_;
  bool have_result_;
  bool waiting_for_result_;
};

#endif  // NET_BASE_TEST_COMPLETION_CALLBACK_H_