// Copyright 2017 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 IPC_IPC_PERFTEST_UTIL_H_
#define IPC_IPC_PERFTEST_UTIL_H_

#include <string>

#if defined(OS_WIN)
#include <windows.h>
#endif

#include "base/callback.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/process/process_metrics.h"
#include "base/single_thread_task_runner.h"
#include "base/task/single_thread_task_executor.h"
#include "build/build_config.h"
#include "ipc/ipc_channel.h"
#include "ipc/ipc_listener.h"
#include "ipc/ipc_message.h"
#include "ipc/ipc_sender.h"
#include "ipc/ipc_test.mojom.h"
#include "mojo/public/cpp/bindings/receiver.h"
#include "mojo/public/cpp/system/core.h"

#if defined(OS_WIN)
#include <windows.h>
#endif

namespace IPC {

scoped_refptr<base::SingleThreadTaskRunner> GetIOThreadTaskRunner();

// This channel listener just replies to all messages with the exact same
// message. It assumes each message has one string parameter. When the string
// "quit" is sent, it will exit.
class ChannelReflectorListener : public Listener {
 public:
  ChannelReflectorListener();

  ~ChannelReflectorListener() override;

  void Init(Sender* channel, const base::Closure& quit_closure);

  bool OnMessageReceived(const Message& message) override;

  void OnHello();

  void OnPing(const std::string& payload);

  void OnSyncPing(const std::string& payload, std::string* response);

  void OnQuit();

  void Send(IPC::Message* message);

 private:
  Sender* channel_;
  base::Closure quit_closure_;
};

// This class locks the current thread to a particular CPU core. This is
// important because otherwise the different threads and processes of these
// tests end up on different CPU cores which means that all of the cores are
// lightly loaded so the OS (Windows and Linux) fails to ramp up the CPU
// frequency, leading to unpredictable and often poor performance.
class LockThreadAffinity {
 public:
  explicit LockThreadAffinity(int cpu_number);

  ~LockThreadAffinity();

 private:
  bool affinity_set_ok_;
#if defined(OS_WIN)
  DWORD_PTR old_affinity_;
#elif defined(OS_LINUX)
  cpu_set_t old_cpuset_;
#endif

  DISALLOW_COPY_AND_ASSIGN(LockThreadAffinity);
};

// Avoid core 0 due to conflicts with Intel's Power Gadget.
// Setting thread affinity will fail harmlessly on single/dual core machines.
const int kSharedCore = 2;

class MojoPerfTestClient {
 public:
  MojoPerfTestClient();

  ~MojoPerfTestClient();

  int Run(MojoHandle handle);

 private:
  base::SingleThreadTaskExecutor main_task_executor_;
  std::unique_ptr<ChannelReflectorListener> listener_;
  std::unique_ptr<Channel> channel_;
  mojo::ScopedMessagePipeHandle handle_;
};

class ReflectorImpl : public IPC::mojom::Reflector {
 public:
  explicit ReflectorImpl(mojo::ScopedMessagePipeHandle handle,
                         const base::Closure& quit_closure);

  ~ReflectorImpl() override;

 private:
  // IPC::mojom::Reflector:
  void Ping(const std::string& value, PingCallback callback) override;

  void SyncPing(const std::string& value, PingCallback callback) override;

  void Quit() override;

  base::Closure quit_closure_;
  mojo::Receiver<IPC::mojom::Reflector> receiver_;
};

}  // namespace IPC

#endif  // IPC_IPC_PERFTEST_UTIL_H_