MyLogger/loghandler.cpp

#include "loghandler.h"
#include <iostream>
#include <QDebug>
#include <QDateTime>
#include <QMutexLocker>
#include <QDir>
#include <QFile>
#include <QFileInfo>
#include <QTimer>
#include <QTextStream>
#include <QTextCodec>
#include "Singleton.h"
#include <QCoreApplication>

QMutex g_mutex;
//QTextStream *g_in = nullptr;
QFile g_file;

// 消息处理函数
void messageHandler(QtMsgType type, const QMessageLogContext &context, const QString &msg)
{
    g_mutex.lock();
    QString level;

    switch (type)
    {
    case QtDebugMsg:
        level = "DEBUG";
        break;
    case QtInfoMsg:
        level = "INFO ";
        break;
    case QtWarningMsg:
        level = "WARN ";
        break;
    case QtCriticalMsg:
        level = "ERROR";
        break;
    case QtFatalMsg:
        level = "FATAL";
        break;
    default:
        break;
    }

    // 输出到标准输出: Windows 下 std::cout 使用 GB2312，而 msg 使用 UTF-8，但是程序的 Local 也还是使用 UTF-8
#if defined(Q_OS_WIN)
    QByteArray localMsg = QTextCodec::codecForName("GB2312")->fromUnicode(msg); //msg.toLocal8Bit();
#else
    QByteArray localMsg = msg.toLocal8Bit();
#endif

    // 输出到日志文件, 格式: 时间 - [Level] (文件名:行数, 函数): 消息
    QString fileName = context.file;
    int index = fileName.lastIndexOf(QDir::separator());
    fileName = fileName.mid(index + 1);
    QString msgOut = QString("%1 - [%2] (%3:%4, %5):    %6")
                     .arg(QDateTime::currentDateTime().toString("yyyy-MM-dd hh:mm:ss")).arg(level)
                     .arg(fileName).arg(context.line).arg(context.function).arg(msg);
    std::cout << msgOut.toLocal8Bit().constData() << std::endl;
    QTextStream in(&g_file);
    in.setCodec("UTF-8");
    in << msgOut << "\n";
//    g_file.flush();
    g_mutex.unlock();
}

// 给Qt安装消息处理函数
void LogHandler::installMessageHandler()
{
    //获取日期
    auto _currentDate = QDateTime::currentDateTime().toString("yyyy-MM-dd");

    //打开/创建文件
    auto _appDirPath = QCoreApplication::applicationDirPath();
    auto _logDirPath = _appDirPath + "/logs/";
    QDir _logDir(_logDirPath);
    if(!_logDir.exists())
        _logDir.mkpath(_logDirPath);

    QString _logPath;
    for(int i = 1; i < 1000; ++i)
    {
        _logPath = _logDirPath + _currentDate + QString("_%1.log").arg(i);
        QFileInfo _fileInfo(_logPath);
        if(!_fileInfo.exists())
        {
            break;
        }
    }

    g_file.setFileName(_logPath);
    if(!g_file.open(QIODevice::WriteOnly | QIODevice::Text | QIODevice::Append))
    {
        return;
    }
//    g_in = new QTextStream(&g_file);
    qInstallMessageHandler(messageHandler); // 给 Qt 安装自定义消息处理函数
}

// 取消安装消息处理函数并释放资源
void LogHandler::uninstallMessageHandler()
{
    g_mutex.lock();
    if(g_file.isOpen())
    {
        g_file.flush();
        g_file.close();
    }
    g_mutex.unlock();
    qInstallMessageHandler(nullptr);
}