Qt日志库Log4Qt的使用，支持文件名/行号/函数名的log打印输出

#################日志库的引入########################
##https://github.com/MEONMedical/Log4Qt
include(Log4Qt-1.5.1/src/log4qt/log4qt.pri)
include(Log4Qt-1.5.1/build.pri)
include(Log4Qt-1.5.1/g++.pri)
QT          += concurrent
DEFINES     += LOG4QT_LIBRARY
DEFINES     += LOG4QT_EXPORT
INCLUDEPATH += Log4Qt-1.5.1/src/
INCLUDEPATH += Log4Qt-1.5.1/src/log4qt
DEPENDPATH  += Log4Qt-1.5.1/src/log4qt
###################################################

C:\Program Files (x86)\Windows Kits\10\Include\10.0.17763.0\um\wingdi.h
/ * Coordinate Modes * /
#define ABSOLUTE 1
#define RELATIVE 2

Log4Qt-1.5.1\src\log4qt\patternlayout.h
 * \brief The class PatternLayout outputs a logging event based on a
 *        pattern string.
        \li c{section_count} : logger name with optional parameter section_count. Section count from end of logger name, sections delimiter is "::";
        \li d{format_string} : date with optional parameters in "{}"-brackets which used by QDateTime::toString();
        \li m : message
        \li p : level name
        \li r : relative date/time to start application
        \li t : thread name
        \li x : ndc name
        \li X : mdc name
        \li F : file name
        \li M : method name
        \li L : line number
Log4Qt-1.5.1\src\log4qt\helpers\patternformatter.cpp
void PatternFormatter::createConverter(QChar character,
                                       Log4Qt::FormattingInfo formattingInfo,
                                       const QString &option)
{
    Q_ASSERT_X(mConversionCharacters.indexOf(character) >= 0, "PatternFormatter::createConverter", "Unknown conversion character" );
    LogError e("Creating Converter for character '%1' min %2, max %3, left %4 and option '%5'");
    e << QString(character)
      << FormattingInfo::intToString(formattingInfo.mMinLength)
      << FormattingInfo::intToString(formattingInfo.mMaxLength)
      << formattingInfo.mLeftAligned
      << option;
    logger()->trace(e);
    switch (character.toLatin1())
    {
    case 'c':
        mPatternConverters << new LoggepatternConverter(formattingInfo,
                           parseIntegeoption(option));
        break;
    case 'd':
    {
        QString format = option;
        if (option.isEmpty())
            format = QStringLiteral("ISO8601");
        else if (option == QLatin1String("locale:long"))
            format = QLocale().dateTimeFormat(QLocale::LongFormat);
        else if (option == QLatin1String("locale:short"))
            format = QLocale().dateTimeFormat(QLocale::ShortFormat);
        else if (option == QLatin1String("locale:narrow"))
            format = QLocale().dateTimeFormat(QLocale::NarrowFormat);
        else if (option == QLatin1String("locale"))
            format = QLocale().dateTimeFormat(QLocale::ShortFormat);
        mPatternConverters << new DatePatternConverter(formattingInfo,
                                                       format);
        break;
    }
    case 'm':
        mPatternConverters << new BasicPatternConverter(formattingInfo,
                                                        BasicPatternConverter::MESSAGE_CONVERTER);
        break;
    case 'p':
        mPatternConverters << new BasicPatternConverter(formattingInfo,
                                                        BasicPatternConverter::LEVEL_CONVERTER);
        break;
    case 'r':
        mPatternConverters << new DatePatternConverter(formattingInfo,
                                                       QStringLiteral("RELATIVE"));
        break;
    case 't':
        mPatternConverters << new BasicPatternConverter(formattingInfo,
                                                        BasicPatternConverter::THREAD_CONVERTER);
        break;
    case 'x':
        mPatternConverters << new BasicPatternConverter(formattingInfo,
                                                        BasicPatternConverter::NDC_CONVERTER);
        break;
    case 'X':
        mPatternConverters << new MDCPatternConverter(formattingInfo,
                                                      option);
        break;
    case 'F':
        mPatternConverters << new BasicPatternConverter(formattingInfo,
                                                        BasicPatternConverter::FILENAME_CONVERTER);
        break;
    case 'M':
        mPatternConverters << new BasicPatternConverter(formattingInfo,
                                                        BasicPatternConverter::FUNCTIONNAME_CONVERTER);
        break;
    case 'L':
        mPatternConverters << new BasicPatternConverter(formattingInfo,
                                                        BasicPatternConverter::LINENUMBER_CONVERTER);
        break;
    case 'l':
        mPatternConverters << new BasicPatternConverter(formattingInfo,
                                                        BasicPatternConverter::LOCATION_CONVERTER);
        break;
    default:
        Q_ASSERT_X(false, "PatternFormatter::createConverter", "Unknown pattern character");
    }
}