十四、获取CPU、内存使用率

ShowCPUMemory.h

#ifndef SHOWCPUMEMORY_H
#define SHOWCPUMEMORY_H

#include <QObject>

class QLabel;
class QTimer;
class QProcess;

class ShowCPUMemory : public QObject
{
  Q_OBJECT
public:
  explicit ShowCPUMemory(QObject *parent = 0);

  void SetLab(QLabel *labCPUMemory);
  void Start(int interval);
  void Stop();

private:
  int totalNew, idleNew, totalOld, idleOld;
  int cpuPercent;

  int memoryPercent;
  int memoryAll;
  int memoryUse;
  int memoryFree;

  QTimer *timerCPU;       //定时器获取CPU信息
  QTimer *timerMemory;    //定时器获取内存信息
  QLabel *labCPUMemory;   //显示CPU内存信息的控件
  QProcess *process;

private slots:
  void GetCPU();
  void GetMemory();
  void ReadData();

signals:

public slots:
};

#endif // SHOWCPUMEMORY_H

ShowCPUMemory.cpp

#if _MSC_VER >= 1600
#pragma execution_character_set("utf-8")
#endif

#include "showcpumemory.h"
#include "myhelper.h"

#ifdef Q_OS_WIN
#ifndef _WIN32_WINNT
#define _WIN32_WINNT 0x502
#endif
#include "windows.h"
#endif
#define MB (1024 * 1024)
#define KB (1024)

ShowCPUMemory::ShowCPUMemory(QObject *parent) : QObject(parent)
{
  totalNew = idleNew = totalOld = idleOld = 0;
  cpuPercent = 0;

  memoryPercent = 0;
  memoryAll = 0;
  memoryUse = 0;
  labCPUMemory = 0;

  timerCPU = new QTimer(this);
  connect(timerCPU, SIGNAL(timeout()), this, SLOT(GetCPU()));

  timerMemory = new QTimer(this);
  connect(timerMemory, SIGNAL(timeout()), this, SLOT(GetMemory()));

  process = new QProcess(this);
  connect(process, SIGNAL(readyRead()), this, SLOT(ReadData()));
}

void ShowCPUMemory::SetLab(QLabel *labCPUMemory)
{
  this->labCPUMemory = labCPUMemory;
  GetCPU();
  myHelper::Sleep(200);
  GetMemory();
}

void ShowCPUMemory::Start(int interval)
{
  timerCPU->start(interval);
  timerMemory->start(interval + 200);
}

void ShowCPUMemory::Stop()
{
  timerCPU->stop();
  timerMemory->stop();
}

void ShowCPUMemory::GetCPU()
{
#ifdef Q_OS_WIN
  static FILETIME preidleTime;
  static FILETIME prekernelTime;
  static FILETIME preuserTime;

  FILETIME idleTime;
  FILETIME kernelTime;
  FILETIME userTime;

  GetSystemTimes(&idleTime, &kernelTime, &userTime);

  quint64 a, b;
  int idle, kernel, user;

  a = (preidleTime.dwHighDateTime << 31) | preidleTime.dwLowDateTime;
  b = (idleTime.dwHighDateTime << 31) | idleTime.dwLowDateTime;
  idle = b - a;

  a = (prekernelTime.dwHighDateTime << 31) | prekernelTime.dwLowDateTime;
  b = (kernelTime.dwHighDateTime << 31) | kernelTime.dwLowDateTime;
  kernel = b - a;

  a = (preuserTime.dwHighDateTime << 31) | preuserTime.dwLowDateTime;
  b = (userTime.dwHighDateTime << 31) | userTime.dwLowDateTime;
  user = b - a;

  cpuPercent = (kernel + user - idle) * 100 / (kernel + user);

  preidleTime = idleTime;
  prekernelTime = kernelTime;
  preuserTime = userTime ;

  QString msg = QString("CPU : %1%  内存 : %2% ( 已用 %3 MB / 共 %4 MB )")
                .arg(cpuPercent).arg(memoryPercent).arg(memoryUse).arg(memoryAll);
  labCPUMemory->setText(msg);
#else

  if (process->state() == QProcess::NotRunning) {
    totalNew = idleNew = 0;
    process->start("cat /proc/stat");
  }

#endif
}

void ShowCPUMemory::GetMemory()
{
#ifdef Q_OS_WIN
#if (QT_VERSION >= QT_VERSION_CHECK(4,8,7))
  MEMORYSTATUSEX statex;
  statex.dwLength = sizeof(statex);
  GlobalMemoryStatusEx(&statex);
  memoryPercent = statex.dwMemoryLoad;
  memoryAll = statex.ullTotalPhys / MB;
  memoryFree = statex.ullAvailPhys / MB;
  memoryUse = memoryAll - memoryFree;

  QString msg = QString("CPU : %1%  内存 : %2% ( 已用 %3 MB / 共 %4 MB )")
                .arg(cpuPercent).arg(memoryPercent).arg(memoryUse).arg(memoryAll);
  labCPUMemory->setText(msg);

  if (memoryPercent > 80) {
    App::WriteError("Memory High");
  }

#endif
#else

  if (process->state() == QProcess::NotRunning) {
    process->start("cat /proc/meminfo");
  }

#endif
}

void ShowCPUMemory::ReadData()
{
  while (!process->atEnd()) {
    QString s = QLatin1String(process->readLine());

    if (s.startsWith("cpu")) {
      QStringList list = s.split(" ");
      idleNew = list.at(5).toInt();

      foreach (QString value, list) {
        totalNew += value.toInt();
      }

      int total = totalNew - totalOld;
      int idle = idleNew - idleOld;
      cpuPercent = 100 * (total - idle) / total;
      totalOld = totalNew;
      idleOld = idleNew;
      break;
    } else if (s.startsWith("MemTotal")) {
      s = s.replace(" ", "");
      s = s.split(":").at(1);
      memoryAll = s.left(s.length() - 3).toInt() / KB;
    } else if (s.startsWith("MemFree")) {
      s = s.replace(" ", "");
      s = s.split(":").at(1);
      memoryFree = s.left(s.length() - 3).toInt() / KB;
    } else if (s.startsWith("Buffers")) {
      s = s.replace(" ", "");
      s = s.split(":").at(1);
      memoryFree += s.left(s.length() - 3).toInt() / KB;
    } else if (s.startsWith("Cached")) {
      s = s.replace(" ", "");
      s = s.split(":").at(1);
      memoryFree += s.left(s.length() - 3).toInt() / KB;
      memoryUse = memoryAll - memoryFree;
      memoryPercent = 100 * memoryUse / memoryAll;
      break;
    }
  }

  QString msg = QString("CPU : %1%  内存 : %2% ( 已用 %3 MB / 共 %4 MB )")
                .arg(cpuPercent).arg(memoryPercent).arg(memoryUse).arg(memoryAll);
  labCPUMemory->setText(msg);

  if (memoryPercent > 80) {
    App::WriteError("Memory High");
  }
}