数据存入文件

超过5M时，新建文件，以时间命名文件名

以下程序是简写部分

#include <ofstream>

class SignalBoardMsg
{
public:
    SignalBoardMsg();
    SignalBoardMsg( SignalBoardMsg _in v ) = delete;
    virtual ~SignalBoardMsg();

private:
    std::string file_name_with_path_;
    void CreateFileByTime( std::ofstream & outfile );
    void WriteFile( std::ofstream & outfile );
    void SetFileNameWithPath( std::string file_name );
    std::string GetFileNameWithPath();
    unsigned long GetFileSize();
    bool MakeDir(std::string file_dir);
};

----------------------------------------------------------------------------------------------------------------------------------

SignalBoardMsg::SignalBoardMsg()
  :  file_name_with_path_("") 
{}

SignalBoardMsg::~SignalBoardMsg()
{
    gps_head_thread_->interrupt();
    gps_head_thread_->join();
    delete gps_head_thread_;
}

bool SignalBoardMsg::MakeDir(string file_dir)
{
    string home_value = getenv("HOME");
    int flag = mkdir((home_value+file_dir).c_str(), 0777);
    if (flag == 0)
    {
        cout<<"make successfully"<<endl;
        return true;
    }
    else
    {
        cout<<"make errorly"<<endl;
        return false;
    }
}

void SignalBoardMsg::SetFileNameWithPath( std::string file_name )
{
    file_name_with_path_.clear();
    string home_value = getenv("HOME");
    file_name_with_path_ = home_value + "/signal_board_data/" + file_name + ".csv";//"/signal_board_data/signal_board.csv";
}

std::string SignalBoardMsg::GetFileNameWithPath()
{
    return file_name_with_path_;
}

void SignalBoardMsg::CreateFileByTime( ofstream & outfile )
{
    time_t time_now;
    struct tm *tm_time_now;
    time (&time_now);
    tm_time_now = localtime(&time_now);
    char show_time[20];
    strftime(show_time, 20, "%Y-%m-%d-%H-%M-%S", tm_time_now); //"%x %X %n%Y-%m-%d%H:%M:%S %nzone: %Z
"
    SetFileNameWithPath(show_time);
    outfile.open(GetFileNameWithPath().c_str(), ios::out | ios::app);
    outfile << "时间" << ","
            << "给定速度X" << "," << "给定速度Y" << "," << "给定速度Z" << ","
            << "反馈速度X" << "," << "反馈速度Y" << "," << "反馈速度Z" << ","
            << "反馈位姿X" << "," << "反馈位姿Y" << "," << "反馈位姿Z" << ","
            << "反馈里程X" << "," << "反馈里程Y" << "," << "反馈里程Z" << ","
            << "陀螺仪X" << "," << "陀螺仪Y" << "," << "陀螺仪Z" << ","
            << "错误码0" << "," << "错误码1" << "," << "错误码2" << ","
            << "错误码3" << "," << "错误码4" << "," << "错误码5" << std::endl;
}

void SignalBoardMsg::WriteFile( ofstream & outfile )
{
    outfile << s_netpack_.TimeStamp << ","
            << s_netpack_.SetRobot.Vel.X << "," << s_netpack_.SetRobot.Vel.Y << "," << s_netpack_.SetRobot.Vel.Z << ","
            << s_netpack_.GetRobot.Vel.X << "," << s_netpack_.GetRobot.Vel.Y << "," << s_netpack_.GetRobot.Vel.Z << ","
            << s_netpack_.GetRobot.Pos.X << "," << s_netpack_.GetRobot.Pos.Y << "," << s_netpack_.GetRobot.Pos.Z << ","
            << s_netpack_.GetRobot.Odom.X << "," << s_netpack_.GetRobot.Odom.Y << "," << s_netpack_.GetRobot.Odom.Z << ","
            << s_netpack_.Gyro.X << "," << s_netpack_.Gyro.Y << "," << s_netpack_.Gyro.Z << ","
            << s_netpack_.ErrorMsg[0].All << "," << s_netpack_.ErrorMsg[1].All << "," << s_netpack_.ErrorMsg[2].All << ","
            << s_netpack_.ErrorMsg[3].All << "," << s_netpack_.ErrorMsg[4].All << "," << s_netpack_.ErrorMsg[5].All << std::endl;
}

unsigned long SignalBoardMsg::GetFileSize()
{
    struct stat buf;
    if (stat(GetFileNameWithPath().c_str(), &buf)<0)
    {
        std::cout << "----------get file size wrong" << std::endl;
        return 0;
    }
    else//bytes=8bit,1024*1024=1Mb=1048576bytes//5M=5242880
    {
//        std::cout << "----------get file size: " << (unsigned long)buf.st_size << std::endl;
        return (unsigned long)buf.st_size;
    }
}

void SignalBoardMsg::Run()
{
  MakeDir("/signal_board_data");
  ofstream outfile;
  CreateFileByTime(outfile);
  ros::Rate rate ( 50 );

  while ( ros::ok() )
  {
      WriteFile(outfile);
      unsigned long file_size = GetFileSize();
      if ( file_size > 5242880 )//5Mb
      {
          outfile.close();
          CreateFileByTime(outfile);
      }
  }
}