qwbot/ServerQueryThread.cpp

/*
GNU General Public License version 3 notice

Copyright (C) 2012 Mihawk <luiz@netdome.biz>. All rights reserved.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see < http://www.gnu.org/licenses/ >.
*/

#include "ServerQueryThread.h"
#include <QReadWriteLock>
#include <QThreadPool>
#include <QThread>

class Sleeper: public QThread
{
public:
  static void msleep(unsigned long msec)
  {
    QThread::msleep(msec);
  }
};

ServerQueryThread::ServerQueryThread():
  QRunnable(),
  myStopMutex(new QReadWriteLock()),
  myServerInfoMutex(new QReadWriteLock()),
  myStopThreadFlag(true),
  myThreadRunningFlag(false),
  myServerPlayerCount(0)
{
  setAutoDelete(false);
  myStopMutex->unlock();
  myServerInfoMutex->unlock();
}

ServerQueryThread::~ServerQueryThread()
{
  delete myStopMutex;
  delete myServerInfoMutex;
}

void ServerQueryThread::setAddress(const QHostAddress &address, quint16 port)
{
  myServerAddress = address;
  myServerPort = port;
  return;
}

bool ServerQueryThread::startQueryThread()
{
  if(!isRunning())
  {
    myStopThreadFlag = false;
    myThreadRunningFlag = true;
    QThreadPool::globalInstance()->start(this);
    return true;
  }
  return false;
}

void ServerQueryThread::stopQueryThread()
{
  myStopMutex->lockForWrite();
  myStopThreadFlag = true;
  myStopMutex->unlock();
}

quint8 ServerQueryThread::playerCount() const
{
  myServerInfoMutex->lockForRead();
  quint8 c = myServerPlayerCount;
  myServerInfoMutex->unlock();
  return c;
}

bool ServerQueryThread::isRunning() const
{
  myStopMutex->lockForRead();
  bool r = myThreadRunningFlag;
  myStopMutex->unlock();
  return r;
}

const QHostAddress& ServerQueryThread::serverAddress() const
{
  return myServerAddress;
}

quint16 ServerQueryThread::serverPort() const
{
  return myServerPort;
}

void ServerQueryThread::run()
{
  ServerQuery* query = new ServerQuery();
  query->setAddress(myServerAddress, myServerPort);

  forever
  {
    /* Handle thread stop request */
    myStopMutex->lockForRead();
    if(myStopThreadFlag)
    {
      myStopMutex->unlock();

      myStopMutex->lockForWrite();
      myThreadRunningFlag = false;
      myStopMutex->unlock();

      delete query;
      return;
    }
    myStopMutex->unlock();

    if(query->query())
    {
      myServerInfoMutex->lockForWrite();
      myServerPlayerCount = query->playerList().size();
      myServerInfoMutex->unlock();
    }
    //    else
    //    {
    //      /* On fail set to 0xff to indicate bad read, so that the client don't act on this */
    //      myServerInfoMutex->lockForWrite();
    //      myServerPlayerCount = 0xff;
    //      myServerInfoMutex->unlock();
    //    }
    Sleeper::msleep(1000);
  }
}