qsettings.cpp

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/****************************************************************************
**
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
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#include <qdebug.h>
#include "qplatformdefs.h"
#include "qsettings.h"

#ifndef QT_NO_SETTINGS

#include "qsettings_p.h"
#include "qcache.h"
#include "qfile.h"
#include "qdir.h"
#include "qfileinfo.h"
#include "qmutex.h"
#include "qlibraryinfo.h"
#include "qtemporaryfile.h"

#ifndef QT_NO_TEXTCODEC
#  include "qtextcodec.h"
#endif

#ifndef QT_NO_GEOM_VARIANT
#include "qsize.h"
#include "qpoint.h"
#include "qrect.h"
#endif // !QT_NO_GEOM_VARIANT

#ifndef QT_NO_QOBJECT
#include "qcoreapplication.h"
#endif

#ifdef Q_OS_WIN // for homedirpath reading from registry
#include "qt_windows.h"
#include <private/qsystemlibrary_p.h>
#endif

#ifdef Q_OS_VXWORKS
#  include <ioLib.h>
#endif

#include <stdlib.h>

#ifndef CSIDL_COMMON_APPDATA
#define CSIDL_COMMON_APPDATA    0x0023  // All Users\Application Data
#endif

#ifndef CSIDL_APPDATA
#define CSIDL_APPDATA       0x001a  // <username>\Application Data
#endif

#ifdef Q_AUTOTEST_EXPORT
#  define Q_AUTOTEST_EXPORT_HELPER Q_AUTOTEST_EXPORT
#else
#  define Q_AUTOTEST_EXPORT_HELPER static
#endif

// ************************************************************************
// QConfFile

/*
    QConfFile objects are explicitly shared within the application.
    This ensures that modification to the settings done through one
    QSettings object are immediately reflected in other setting
    objects of the same application.
*/

QT_BEGIN_NAMESPACE

struct QConfFileCustomFormat
{
    QString extension;
    QSettings::ReadFunc readFunc;
    QSettings::WriteFunc writeFunc;
    Qt::CaseSensitivity caseSensitivity;
};

typedef QHash<QString, QConfFile *> ConfFileHash;
typedef QCache<QString, QConfFile> ConfFileCache;
typedef QHash<int, QString> PathHash;
typedef QVector<QConfFileCustomFormat> CustomFormatVector;

Q_GLOBAL_STATIC(ConfFileHash, usedHashFunc)
Q_GLOBAL_STATIC(ConfFileCache, unusedCacheFunc)
Q_GLOBAL_STATIC(PathHash, pathHashFunc)
Q_GLOBAL_STATIC(CustomFormatVector, customFormatVectorFunc)
Q_GLOBAL_STATIC(QMutex, globalMutex)
static QSettings::Format globalDefaultFormat = QSettings::NativeFormat;

#ifndef Q_OS_WIN
inline bool qt_isEvilFsTypeName(const char *name)
{
    return (qstrncmp(name, "nfs", 3) == 0
            || qstrncmp(name, "autofs", 6) == 0
            || qstrncmp(name, "cachefs", 7) == 0);
}

#if defined(Q_OS_BSD4) && !defined(Q_OS_NETBSD)
QT_BEGIN_INCLUDE_NAMESPACE
# include <sys/param.h>
# include <sys/mount.h>
QT_END_INCLUDE_NAMESPACE

Q_AUTOTEST_EXPORT_HELPER bool qIsLikelyToBeNfs(int handle)
{
    struct statfs buf;
    if (fstatfs(handle, &buf) != 0)
        return false;
    return qt_isEvilFsTypeName(buf.f_fstypename);
}

#elif defined(Q_OS_LINUX) || defined(Q_OS_HURD)
QT_BEGIN_INCLUDE_NAMESPACE
# include <sys/vfs.h>
# ifdef QT_LINUXBASE
   // LSB 3.2 has fstatfs in sys/statfs.h, sys/vfs.h is just an empty dummy header
#  include <sys/statfs.h>
# endif
QT_END_INCLUDE_NAMESPACE
# ifndef NFS_SUPER_MAGIC
#  define NFS_SUPER_MAGIC       0x00006969
# endif
# ifndef AUTOFS_SUPER_MAGIC
#  define AUTOFS_SUPER_MAGIC    0x00000187
# endif
# ifndef AUTOFSNG_SUPER_MAGIC
#  define AUTOFSNG_SUPER_MAGIC  0x7d92b1a0
# endif

Q_AUTOTEST_EXPORT_HELPER bool qIsLikelyToBeNfs(int handle)
{
    struct statfs buf;
    if (fstatfs(handle, &buf) != 0)
        return false;
    return buf.f_type == NFS_SUPER_MAGIC
           || buf.f_type == AUTOFS_SUPER_MAGIC
           || buf.f_type == AUTOFSNG_SUPER_MAGIC;
}

#elif defined(Q_OS_SOLARIS) || defined(Q_OS_IRIX) || defined(Q_OS_AIX) || defined(Q_OS_HPUX) \
      || defined(Q_OS_OSF) || defined(Q_OS_QNX) || defined(Q_OS_SCO) \
      || defined(Q_OS_UNIXWARE) || defined(Q_OS_RELIANT) || defined(Q_OS_NETBSD)
QT_BEGIN_INCLUDE_NAMESPACE
# include <sys/statvfs.h>
QT_END_INCLUDE_NAMESPACE

Q_AUTOTEST_EXPORT_HELPER bool qIsLikelyToBeNfs(int handle)
{
    struct statvfs buf;
    if (fstatvfs(handle, &buf) != 0)
        return false;
#if defined(Q_OS_NETBSD)
    return qt_isEvilFsTypeName(buf.f_fstypename);
#else
    return qt_isEvilFsTypeName(buf.f_basetype);
#endif
}
#else
Q_AUTOTEST_EXPORT_HELPER inline bool qIsLikelyToBeNfs(int /* handle */)
{
    return true;
}
#endif

static bool unixLock(int handle, int lockType)
{
    /*
        NFS hangs on the fcntl() call below when statd or lockd isn't
        running. There's no way to detect this. Our work-around for
        now is to disable locking when we detect NFS (or AutoFS or
        CacheFS, which are probably wrapping NFS).
    */
    if (qIsLikelyToBeNfs(handle))
        return false;

    struct flock fl;
    fl.l_whence = SEEK_SET;
    fl.l_start = 0;
    fl.l_len = 0;
    fl.l_type = lockType;
    return fcntl(handle, F_SETLKW, &fl) == 0;
}
#endif

QConfFile::QConfFile(const QString &fileName, bool _userPerms)
    : name(fileName), size(0), ref(1), userPerms(_userPerms)
{
    usedHashFunc()->insert(name, this);
}

QConfFile::~QConfFile()
{
    if (usedHashFunc())
        usedHashFunc()->remove(name);
}

ParsedSettingsMap QConfFile::mergedKeyMap() const
{
    ParsedSettingsMap result = originalKeys;
    ParsedSettingsMap::const_iterator i;

    for (i = removedKeys.begin(); i != removedKeys.end(); ++i)
        result.remove(i.key());
    for (i = addedKeys.begin(); i != addedKeys.end(); ++i)
        result.insert(i.key(), i.value());
    return result;
}

bool QConfFile::isWritable() const
{
    QFileInfo fileInfo(name);

#ifndef QT_NO_TEMPORARYFILE
    if (fileInfo.exists()) {
#endif
        QFile file(name);
        return file.open(QFile::ReadWrite);
#ifndef QT_NO_TEMPORARYFILE
    } else {
        // Create the directories to the file.
        QDir dir(fileInfo.absolutePath());
        if (!dir.exists()) {
            if (!dir.mkpath(dir.absolutePath()))
                return false;
        }

        // we use a temporary file to avoid race conditions
        QTemporaryFile file(name);
        return file.open();
    }
#endif
}

QConfFile *QConfFile::fromName(const QString &fileName, bool _userPerms)
{
    QString absPath = QFileInfo(fileName).absoluteFilePath();

    ConfFileHash *usedHash = usedHashFunc();
    ConfFileCache *unusedCache = unusedCacheFunc();

    QConfFile *confFile = 0;
    QMutexLocker locker(globalMutex());

    if (!(confFile = usedHash->value(absPath))) {
        if ((confFile = unusedCache->take(absPath)))
            usedHash->insert(absPath, confFile);
    }
    if (confFile) {
        confFile->ref.ref();
        return confFile;
    }
    return new QConfFile(absPath, _userPerms);
}

void QConfFile::clearCache()
{
    QMutexLocker locker(globalMutex());
    unusedCacheFunc()->clear();
}

// ************************************************************************
// QSettingsPrivate

QSettingsPrivate::QSettingsPrivate(QSettings::Format format)
    : format(format), scope(QSettings::UserScope /* nothing better to put */), iniCodec(0), spec(0), fallbacks(true),
      pendingChanges(false), status(QSettings::NoError)
{
}

QSettingsPrivate::QSettingsPrivate(QSettings::Format format, QSettings::Scope scope,
                                   const QString &organization, const QString &application)
    : format(format), scope(scope), organizationName(organization), applicationName(application),
      iniCodec(0), spec(0), fallbacks(true), pendingChanges(false), status(QSettings::NoError)
{
}

QSettingsPrivate::~QSettingsPrivate()
{
}

QString QSettingsPrivate::actualKey(const QString &key) const
{
    QString n = normalizedKey(key);
    Q_ASSERT_X(!n.isEmpty(), "QSettings", "empty key");
    n.prepend(groupPrefix);
    return n;
}

/*
    Returns a string that never starts nor ends with a slash (or an
    empty string). Examples:

            "foo"            becomes   "foo"
            "/foo//bar///"   becomes   "foo/bar"
            "///"            becomes   ""

    This function is optimized to avoid a QString deep copy in the
    common case where the key is already normalized.
*/
QString QSettingsPrivate::normalizedKey(const QString &key)
{
    QString result = key;

    int i = 0;
    while (i < result.size()) {
        while (result.at(i) == QLatin1Char('/')) {
            result.remove(i, 1);
            if (i == result.size())
                goto after_loop;
        }
        while (result.at(i) != QLatin1Char('/')) {
            ++i;
            if (i == result.size())
                return result;
        }
        ++i; // leave the slash alone
    }

after_loop:
    if (!result.isEmpty())
        result.truncate(i - 1); // remove the trailing slash
    return result;
}

// see also qsettings_win.cpp and qsettings_mac.cpp

#if !defined(Q_OS_WIN) && !defined(Q_OS_MAC)
QSettingsPrivate *QSettingsPrivate::create(QSettings::Format format, QSettings::Scope scope,
                                           const QString &organization, const QString &application)
{
    return new QConfFileSettingsPrivate(format, scope, organization, application);
}
#endif

#if !defined(Q_OS_WIN)
QSettingsPrivate *QSettingsPrivate::create(const QString &fileName, QSettings::Format format)
{
    return new QConfFileSettingsPrivate(fileName, format);
}
#endif

void QSettingsPrivate::processChild(QString key, ChildSpec spec, QMap<QString, QString> &result)
{
    if (spec != AllKeys) {
        int slashPos = key.indexOf(QLatin1Char('/'));
        if (slashPos == -1) {
            if (spec != ChildKeys)
                return;
        } else {
            if (spec != ChildGroups)
                return;
            key.truncate(slashPos);
        }
    }
    result.insert(key, QString());
}

void QSettingsPrivate::beginGroupOrArray(const QSettingsGroup &group)
{
    groupStack.push(group);
    if (!group.name().isEmpty()) {
        groupPrefix += group.name();
        groupPrefix += QLatin1Char('/');
    }
}

/*
    We only set an error if there isn't one set already. This way the user always gets the
    first error that occurred. We always allow clearing errors.
*/

void QSettingsPrivate::setStatus(QSettings::Status status) const
{
    if (status == QSettings::NoError || this->status == QSettings::NoError)
        this->status = status;
}

void QSettingsPrivate::update()
{
    flush();
    pendingChanges = false;
}

void QSettingsPrivate::requestUpdate()
{
    if (!pendingChanges) {
        pendingChanges = true;
#ifndef QT_NO_QOBJECT
        Q_Q(QSettings);
        QCoreApplication::postEvent(q, new QEvent(QEvent::UpdateRequest));
#else
        update();
#endif
    }
}

QStringList QSettingsPrivate::variantListToStringList(const QVariantList &l)
{
    QStringList result;
    QVariantList::const_iterator it = l.constBegin();
    for (; it != l.constEnd(); ++it)
        result.append(variantToString(*it));
    return result;
}

QVariant QSettingsPrivate::stringListToVariantList(const QStringList &l)
{
    QStringList outStringList = l;
    for (int i = 0; i < outStringList.count(); ++i) {
        const QString &str = outStringList.at(i);

        if (str.startsWith(QLatin1Char('@'))) {
            if (str.length() >= 2 && str.at(1) == QLatin1Char('@')) {
                outStringList[i].remove(0, 1);
            } else {
                QVariantList variantList;
                for (int j = 0; j < l.count(); ++j)
                    variantList.append(stringToVariant(l.at(j)));
                return variantList;
            }
        }
    }
    return outStringList;
}

QString QSettingsPrivate::variantToString(const QVariant &v)
{
    QString result;

    switch (v.type()) {
        case QVariant::Invalid:
            result = QLatin1String("@Invalid()");
            break;

        case QVariant::ByteArray: {
            QByteArray a = v.toByteArray();
            result = QLatin1String("@ByteArray(");
            result += QString::fromLatin1(a.constData(), a.size());
            result += QLatin1Char(')');
            break;
        }

        case QVariant::String:
        case QVariant::LongLong:
        case QVariant::ULongLong:
        case QVariant::Int:
        case QVariant::UInt:
        case QVariant::Bool:
        case QVariant::Double:
        case QVariant::KeySequence: {
            result = v.toString();
            if (result.startsWith(QLatin1Char('@')))
                result.prepend(QLatin1Char('@'));
            break;
        }
#ifndef QT_NO_GEOM_VARIANT
        case QVariant::Rect: {
            QRect r = qvariant_cast<QRect>(v);
            result += QLatin1String("@Rect(");
            result += QString::number(r.x());
            result += QLatin1Char(' ');
            result += QString::number(r.y());
            result += QLatin1Char(' ');
            result += QString::number(r.width());
            result += QLatin1Char(' ');
            result += QString::number(r.height());
            result += QLatin1Char(')');
            break;
        }
        case QVariant::Size: {
            QSize s = qvariant_cast<QSize>(v);
            result += QLatin1String("@Size(");
            result += QString::number(s.width());
            result += QLatin1Char(' ');
            result += QString::number(s.height());
            result += QLatin1Char(')');
            break;
        }
        case QVariant::Point: {
            QPoint p = qvariant_cast<QPoint>(v);
            result += QLatin1String("@Point(");
            result += QString::number(p.x());
            result += QLatin1Char(' ');
            result += QString::number(p.y());
            result += QLatin1Char(')');
            break;
        }
#endif // !QT_NO_GEOM_VARIANT

        default: {
#ifndef QT_NO_DATASTREAM
            QByteArray a;
            {
                QDataStream s(&a, QIODevice::WriteOnly);
                s.setVersion(QDataStream::Qt_4_0);
                s << v;
            }

            result = QLatin1String("@Variant(");
            result += QString::fromLatin1(a.constData(), a.size());
            result += QLatin1Char(')');
#else
            Q_ASSERT(!"QSettings: Cannot save custom types without QDataStream support");
#endif
            break;
        }
    }

    return result;
}


QVariant QSettingsPrivate::stringToVariant(const QString &s)
{
    if (s.startsWith(QLatin1Char('@'))) {
        if (s.endsWith(QLatin1Char(')'))) {
            if (s.startsWith(QLatin1String("@ByteArray("))) {
                return QVariant(s.toLatin1().mid(11, s.size() - 12));
            } else if (s.startsWith(QLatin1String("@Variant("))) {
#ifndef QT_NO_DATASTREAM
                QByteArray a(s.toLatin1().mid(9));
                QDataStream stream(&a, QIODevice::ReadOnly);
                stream.setVersion(QDataStream::Qt_4_0);
                QVariant result;
                stream >> result;
                return result;
#else
                Q_ASSERT(!"QSettings: Cannot load custom types without QDataStream support");
#endif
#ifndef QT_NO_GEOM_VARIANT
            } else if (s.startsWith(QLatin1String("@Rect("))) {
                QStringList args = QSettingsPrivate::splitArgs(s, 5);
                if (args.size() == 4)
                    return QVariant(QRect(args[0].toInt(), args[1].toInt(), args[2].toInt(), args[3].toInt()));
            } else if (s.startsWith(QLatin1String("@Size("))) {
                QStringList args = QSettingsPrivate::splitArgs(s, 5);
                if (args.size() == 2)
                    return QVariant(QSize(args[0].toInt(), args[1].toInt()));
            } else if (s.startsWith(QLatin1String("@Point("))) {
                QStringList args = QSettingsPrivate::splitArgs(s, 6);
                if (args.size() == 2)
                    return QVariant(QPoint(args[0].toInt(), args[1].toInt()));
#endif
            } else if (s == QLatin1String("@Invalid()")) {
                return QVariant();
            }

        }
        if (s.startsWith(QLatin1String("@@")))
            return QVariant(s.mid(1));
    }

    return QVariant(s);
}

static const char hexDigits[] = "0123456789ABCDEF";

void QSettingsPrivate::iniEscapedKey(const QString &key, QByteArray &result)
{
    result.reserve(result.length() + key.length() * 3 / 2);
    for (int i = 0; i < key.size(); ++i) {
        uint ch = key.at(i).unicode();

        if (ch == '/') {
            result += '\\';
        } else if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') || (ch >= '0' && ch <= '9')
                || ch == '_' || ch == '-' || ch == '.') {
            result += (char)ch;
        } else if (ch <= 0xFF) {
            result += '%';
            result += hexDigits[ch / 16];
            result += hexDigits[ch % 16];
        } else {
            result += "%U";
            QByteArray hexCode;
            for (int i = 0; i < 4; ++i) {
                hexCode.prepend(hexDigits[ch % 16]);
                ch >>= 4;
            }
            result += hexCode;
        }
    }
}

bool QSettingsPrivate::iniUnescapedKey(const QByteArray &key, int from, int to, QString &result)
{
    bool lowercaseOnly = true;
    int i = from;
    result.reserve(result.length() + (to - from));
    while (i < to) {
        int ch = (uchar)key.at(i);

        if (ch == '\\') {
            result += QLatin1Char('/');
            ++i;
            continue;
        }

        if (ch != '%' || i == to - 1) {
            if (uint(ch - 'A') <= 'Z' - 'A') // only for ASCII
                lowercaseOnly = false;
            result += QLatin1Char(ch);
            ++i;
            continue;
        }

        int numDigits = 2;
        int firstDigitPos = i + 1;

        ch = key.at(i + 1);
        if (ch == 'U') {
            ++firstDigitPos;
            numDigits = 4;
        }

        if (firstDigitPos + numDigits > to) {
            result += QLatin1Char('%');
            // ### missing U
            ++i;
            continue;
        }

        bool ok;
        ch = key.mid(firstDigitPos, numDigits).toInt(&ok, 16);
        if (!ok) {
            result += QLatin1Char('%');
            // ### missing U
            ++i;
            continue;
        }

        QChar qch(ch);
        if (qch.isUpper())
            lowercaseOnly = false;
        result += qch;
        i = firstDigitPos + numDigits;
    }
    return lowercaseOnly;
}

void QSettingsPrivate::iniEscapedString(const QString &str, QByteArray &result, QTextCodec *codec)
{
    bool needsQuotes = false;
    bool escapeNextIfDigit = false;
    int i;
    int startPos = result.size();

    result.reserve(startPos + str.size() * 3 / 2);
    for (i = 0; i < str.size(); ++i) {
        uint ch = str.at(i).unicode();
        if (ch == ';' || ch == ',' || ch == '=')
            needsQuotes = true;

        if (escapeNextIfDigit
                && ((ch >= '0' && ch <= '9')
                    || (ch >= 'a' && ch <= 'f')
                    || (ch >= 'A' && ch <= 'F'))) {
            result += "\\x";
            result += QByteArray::number(ch, 16);
            continue;
        }

        escapeNextIfDigit = false;

        switch (ch) {
        case '\0':
            result += "\\0";
            escapeNextIfDigit = true;
            break;
        case '\a':
            result += "\\a";
            break;
        case '\b':
            result += "\\b";
            break;
        case '\f':
            result += "\\f";
            break;
        case '\n':
            result += "\\n";
            break;
        case '\r':
            result += "\\r";
            break;
        case '\t':
            result += "\\t";
            break;
        case '\v':
            result += "\\v";
            break;
        case '"':
        case '\\':
            result += '\\';
            result += (char)ch;
            break;
        default:
            if (ch <= 0x1F || (ch >= 0x7F && !codec)) {
                result += "\\x";
                result += QByteArray::number(ch, 16);
                escapeNextIfDigit = true;
#ifndef QT_NO_TEXTCODEC
            } else if (codec) {
                // slow
                result += codec->fromUnicode(str.at(i));
#endif
            } else {
                result += (char)ch;
            }
        }
    }

    if (needsQuotes
            || (startPos < result.size() && (result.at(startPos) == ' '
                                                || result.at(result.size() - 1) == ' '))) {
        result.insert(startPos, '"');
        result += '"';
    }
}

inline static void iniChopTrailingSpaces(QString &str)
{
    int n = str.size() - 1;
    QChar ch;
    while (n >= 0 && ((ch = str.at(n)) == QLatin1Char(' ') || ch == QLatin1Char('\t')))
        str.truncate(n--);
}

void QSettingsPrivate::iniEscapedStringList(const QStringList &strs, QByteArray &result, QTextCodec *codec)
{
    if (strs.isEmpty()) {
        /*
            We need to distinguish between empty lists and one-item
            lists that contain an empty string. Ideally, we'd have a
            @EmptyList() symbol but that would break compatibility
            with Qt 4.0. @Invalid() stands for QVariant(), and
            QVariant().toStringList() returns an empty QStringList,
            so we're in good shape.

            ### Qt 5: Use a nicer syntax, e.g. @List, for variant lists
        */
        result += "@Invalid()";
    } else {
        for (int i = 0; i < strs.size(); ++i) {
            if (i != 0)
                result += ", ";
            iniEscapedString(strs.at(i), result, codec);
        }
    }
}

bool QSettingsPrivate::iniUnescapedStringList(const QByteArray &str, int from, int to,
                                              QString &stringResult, QStringList &stringListResult,
                                              QTextCodec *codec)
{
#ifdef QT_NO_TEXTCODE
    Q_UNUSED(codec);
#endif
    static const char escapeCodes[][2] =
    {
        { 'a', '\a' },
        { 'b', '\b' },
        { 'f', '\f' },
        { 'n', '\n' },
        { 'r', '\r' },
        { 't', '\t' },
        { 'v', '\v' },
        { '"', '"' },
        { '?', '?' },
        { '\'', '\'' },
        { '\\', '\\' }
    };
    static const int numEscapeCodes = sizeof(escapeCodes) / sizeof(escapeCodes[0]);

    bool isStringList = false;
    bool inQuotedString = false;
    bool currentValueIsQuoted = false;
    int escapeVal = 0;
    int i = from;
    char ch;

StSkipSpaces:
    while (i < to && ((ch = str.at(i)) == ' ' || ch == '\t'))
        ++i;
    // fallthrough

StNormal:
    while (i < to) {
        switch (str.at(i)) {
        case '\\':
            ++i;
            if (i >= to)
                goto end;

            ch = str.at(i++);
            for (int j = 0; j < numEscapeCodes; ++j) {
                if (ch == escapeCodes[j][0]) {
                    stringResult += QLatin1Char(escapeCodes[j][1]);
                    goto StNormal;
                }
            }

            if (ch == 'x') {
                escapeVal = 0;

                if (i >= to)
                    goto end;

                ch = str.at(i);
                if ((ch >= '0' && ch <= '9') || (ch >= 'A' && ch <= 'F') || (ch >= 'a' && ch <= 'f'))
                    goto StHexEscape;
            } else if (ch >= '0' && ch <= '7') {
                escapeVal = ch - '0';
                goto StOctEscape;
            } else if (ch == '\n' || ch == '\r') {
                if (i < to) {
                    char ch2 = str.at(i);
                    // \n, \r, \r\n, and \n\r are legitimate line terminators in INI files
                    if ((ch2 == '\n' || ch2 == '\r') && ch2 != ch)
                        ++i;
                }
            } else {
                // the character is skipped
            }
            break;
        case '"':
            ++i;
            currentValueIsQuoted = true;
            inQuotedString = !inQuotedString;
            if (!inQuotedString)
                goto StSkipSpaces;
            break;
        case ',':
            if (!inQuotedString) {
                if (!currentValueIsQuoted)
                    iniChopTrailingSpaces(stringResult);
                if (!isStringList) {
                    isStringList = true;
                    stringListResult.clear();
                    stringResult.squeeze();
                }
                stringListResult.append(stringResult);
                stringResult.clear();
                currentValueIsQuoted = false;
                ++i;
                goto StSkipSpaces;
            }
            // fallthrough
        default: {
            int j = i + 1;
            while (j < to) {
                ch = str.at(j);
                if (ch == '\\' || ch == '"' || ch == ',')
                    break;
                ++j;
            }

#ifndef QT_NO_TEXTCODEC
            if (codec) {
                stringResult += codec->toUnicode(str.constData() + i, j - i);
            } else
#endif
            {
                int n = stringResult.size();
                stringResult.resize(n + (j - i));
                QChar *resultData = stringResult.data() + n;
                for (int k = i; k < j; ++k)
                    *resultData++ = QLatin1Char(str.at(k));
            }
            i = j;
        }
        }
    }
    goto end;

StHexEscape:
    if (i >= to) {
        stringResult += QChar(escapeVal);
        goto end;
    }

    ch = str.at(i);
    if (ch >= 'a')
        ch -= 'a' - 'A';
    if ((ch >= '0' && ch <= '9') || (ch >= 'A' && ch <= 'F')) {
        escapeVal <<= 4;
        escapeVal += strchr(hexDigits, ch) - hexDigits;
        ++i;
        goto StHexEscape;
    } else {
        stringResult += QChar(escapeVal);
        goto StNormal;
    }

StOctEscape:
    if (i >= to) {
        stringResult += QChar(escapeVal);
        goto end;
    }

    ch = str.at(i);
    if (ch >= '0' && ch <= '7') {
        escapeVal <<= 3;
        escapeVal += ch - '0';
        ++i;
        goto StOctEscape;
    } else {
        stringResult += QChar(escapeVal);
        goto StNormal;
    }

end:
    if (!currentValueIsQuoted)
        iniChopTrailingSpaces(stringResult);
    if (isStringList)
        stringListResult.append(stringResult);
    return isStringList;
}

QStringList QSettingsPrivate::splitArgs(const QString &s, int idx)
{
    int l = s.length();
    Q_ASSERT(l > 0);
    Q_ASSERT(s.at(idx) == QLatin1Char('('));
    Q_ASSERT(s.at(l - 1) == QLatin1Char(')'));

    QStringList result;
    QString item;

    for (++idx; idx < l; ++idx) {
        QChar c = s.at(idx);
        if (c == QLatin1Char(')')) {
            Q_ASSERT(idx == l - 1);
            result.append(item);
        } else if (c == QLatin1Char(' ')) {
            result.append(item);
            item.clear();
        } else {
            item.append(c);
        }
    }

    return result;
}

// ************************************************************************
// QConfFileSettingsPrivate

void QConfFileSettingsPrivate::initFormat()
{
    extension = (format == QSettings::NativeFormat) ? QLatin1String(".conf") : QLatin1String(".ini");
    readFunc = 0;
    writeFunc = 0;
#if defined(Q_OS_MAC)
    caseSensitivity = (format == QSettings::NativeFormat) ? Qt::CaseSensitive : IniCaseSensitivity;
#else
    caseSensitivity = IniCaseSensitivity;
#endif

    if (format > QSettings::IniFormat) {
        QMutexLocker locker(globalMutex());
        const CustomFormatVector *customFormatVector = customFormatVectorFunc();

        int i = (int)format - (int)QSettings::CustomFormat1;
        if (i >= 0 && i < customFormatVector->size()) {
            QConfFileCustomFormat info = customFormatVector->at(i);
            extension = info.extension;
            readFunc = info.readFunc;
            writeFunc = info.writeFunc;
            caseSensitivity = info.caseSensitivity;
        }
    }
}

void QConfFileSettingsPrivate::initAccess()
{
    if (confFiles[spec]) {
        if (format > QSettings::IniFormat) {
            if (!readFunc)
                setStatus(QSettings::AccessError);
        }
    }

    sync();       // loads the files the first time
}

#ifdef Q_OS_WIN
static QString windowsConfigPath(int type)
{
    QString result;

#ifndef Q_OS_WINCE
    QSystemLibrary library(QLatin1String("shell32"));
#else
    QSystemLibrary library(QLatin1String("coredll"));
#endif // Q_OS_WINCE
    typedef BOOL (WINAPI*GetSpecialFolderPath)(HWND, LPWSTR, int, BOOL);
    GetSpecialFolderPath SHGetSpecialFolderPath = (GetSpecialFolderPath)library.resolve("SHGetSpecialFolderPathW");
    if (SHGetSpecialFolderPath) {
        wchar_t path[MAX_PATH];
        SHGetSpecialFolderPath(0, path, type, FALSE);
        result = QString::fromWCharArray(path);
    }

    if (result.isEmpty()) {
        switch (type) {
#ifndef Q_OS_WINCE
        case CSIDL_COMMON_APPDATA:
            result = QLatin1String("C:\\temp\\qt-common");
            break;
        case CSIDL_APPDATA:
            result = QLatin1String("C:\\temp\\qt-user");
            break;
#else
        case CSIDL_COMMON_APPDATA:
            result = QLatin1String("\\Temp\\qt-common");
            break;
        case CSIDL_APPDATA:
            result = QLatin1String("\\Temp\\qt-user");
            break;
#endif
        default:
            ;
        }
    }

    return result;
}
#endif // Q_OS_WIN

static inline int pathHashKey(QSettings::Format format, QSettings::Scope scope)
{
    return int((uint(format) << 1) | uint(scope == QSettings::SystemScope));
}

static void initDefaultPaths(QMutexLocker *locker)
{
    PathHash *pathHash = pathHashFunc();
    QString homePath = QDir::homePath();
    QString systemPath;

    locker->unlock();

    /*
       QLibraryInfo::location() uses QSettings, so in order to
       avoid a dead-lock, we can't hold the global mutex while
       calling it.
    */
    systemPath = QLibraryInfo::location(QLibraryInfo::SettingsPath);
    systemPath += QLatin1Char('/');

    locker->relock();
    if (pathHash->isEmpty()) {
        /*
           Lazy initialization of pathHash. We initialize the
           IniFormat paths and (on Unix) the NativeFormat paths.
           (The NativeFormat paths are not configurable for the
           Windows registry and the Mac CFPreferences.)
       */
#ifdef Q_OS_WIN
        pathHash->insert(pathHashKey(QSettings::IniFormat, QSettings::UserScope),
                         windowsConfigPath(CSIDL_APPDATA) + QDir::separator());
        pathHash->insert(pathHashKey(QSettings::IniFormat, QSettings::SystemScope),
                         windowsConfigPath(CSIDL_COMMON_APPDATA) + QDir::separator());
#else
        QString userPath;
        char *env = getenv("XDG_CONFIG_HOME");
        if (env == 0) {
            userPath = homePath;
            userPath += QLatin1Char('/');
#if defined(Q_WS_QWS) || defined(Q_WS_QPA)
            userPath += QLatin1String("Settings");
#else
            userPath += QLatin1String(".config");
#endif
        } else if (*env == '/') {
            userPath = QFile::decodeName(env);
        } else {
            userPath = homePath;
            userPath += QLatin1Char('/');
            userPath += QFile::decodeName(env);
        }
        userPath += QLatin1Char('/');

        pathHash->insert(pathHashKey(QSettings::IniFormat, QSettings::UserScope), userPath);
        pathHash->insert(pathHashKey(QSettings::IniFormat, QSettings::SystemScope), systemPath);
#ifndef Q_OS_MAC
        pathHash->insert(pathHashKey(QSettings::NativeFormat, QSettings::UserScope), userPath);
        pathHash->insert(pathHashKey(QSettings::NativeFormat, QSettings::SystemScope), systemPath);
#endif
#endif
    }
}

static QString getPath(QSettings::Format format, QSettings::Scope scope)
{
    Q_ASSERT((int)QSettings::NativeFormat == 0);
    Q_ASSERT((int)QSettings::IniFormat == 1);

    QMutexLocker locker(globalMutex());
    PathHash *pathHash = pathHashFunc();
    if (pathHash->isEmpty())
        initDefaultPaths(&locker);

    QString result = pathHash->value(pathHashKey(format, scope));
    if (!result.isEmpty())
        return result;

    // fall back on INI path
    return pathHash->value(pathHashKey(QSettings::IniFormat, scope));
}

QConfFileSettingsPrivate::QConfFileSettingsPrivate(QSettings::Format format,
                                                   QSettings::Scope scope,
                                                   const QString &organization,
                                                   const QString &application)
    : QSettingsPrivate(format, scope, organization, application),
      nextPosition(0x40000000) // big positive number
{
    int i;
    initFormat();

    QString org = organization;
    if (org.isEmpty()) {
        setStatus(QSettings::AccessError);
        org = QLatin1String("Unknown Organization");
    }

#if !defined(Q_OS_BLACKBERRY)
    QString appFile = org + QDir::separator() + application + extension;
    QString orgFile = org + extension;

    if (scope == QSettings::UserScope) {
        QString userPath = getPath(format, QSettings::UserScope);
        if (!application.isEmpty())
            confFiles[F_User | F_Application].reset(QConfFile::fromName(userPath + appFile, true));
        confFiles[F_User | F_Organization].reset(QConfFile::fromName(userPath + orgFile, true));
    }

    QString systemPath = getPath(format, QSettings::SystemScope);
    if (!application.isEmpty())
        confFiles[F_System | F_Application].reset(QConfFile::fromName(systemPath + appFile, false));
    confFiles[F_System | F_Organization].reset(QConfFile::fromName(systemPath + orgFile, false));
#else
    QString confName = getPath(format, QSettings::UserScope) + org;
    if (!application.isEmpty())
        confName += QDir::separator() + application;
    confName += extension;
    confFiles[SandboxConfFile].reset(QConfFile::fromName(confName, true));
#endif

    for (i = 0; i < NumConfFiles; ++i) {
        if (confFiles[i]) {
            spec = i;
            break;
        }
    }

    initAccess();
}

QConfFileSettingsPrivate::QConfFileSettingsPrivate(const QString &fileName,
                                                   QSettings::Format format)
    : QSettingsPrivate(format),
      nextPosition(0x40000000) // big positive number
{
    initFormat();

    confFiles[0].reset(QConfFile::fromName(fileName, true));

    initAccess();
}

QConfFileSettingsPrivate::~QConfFileSettingsPrivate()
{
    QMutexLocker locker(globalMutex());
    ConfFileHash *usedHash = usedHashFunc();
    ConfFileCache *unusedCache = unusedCacheFunc();

    for (int i = 0; i < NumConfFiles; ++i) {
        if (confFiles[i] && !confFiles[i]->ref.deref()) {
            if (confFiles[i]->size == 0) {
                delete confFiles[i].take();
            } else {
                if (usedHash)
                    usedHash->remove(confFiles[i]->name);
                if (unusedCache) {
                    QT_TRY {
                        // compute a better size?
                        unusedCache->insert(confFiles[i]->name, confFiles[i].data(),
                                        10 + (confFiles[i]->originalKeys.size() / 4));
                        confFiles[i].take();
                    } QT_CATCH(...) {
                        // out of memory. Do not cache the file.
                        delete confFiles[i].take();
                    }
                } else {
                    // unusedCache is gone - delete the entry to prevent a memory leak
                    delete confFiles[i].take();
                }
            }
        }
        // prevent the ScopedPointer to deref it again.
        confFiles[i].take();
    }
}

void QConfFileSettingsPrivate::remove(const QString &key)
{
    QConfFile *confFile = confFiles[spec].data();
    if (!confFile)
        return;

    QSettingsKey theKey(key, caseSensitivity);
    QSettingsKey prefix(key + QLatin1Char('/'), caseSensitivity);
    QMutexLocker locker(&confFile->mutex);

    ensureSectionParsed(confFile, theKey);
    ensureSectionParsed(confFile, prefix);

    ParsedSettingsMap::iterator i = confFile->addedKeys.lowerBound(prefix);
    while (i != confFile->addedKeys.end() && i.key().startsWith(prefix))
        i = confFile->addedKeys.erase(i);
    confFile->addedKeys.remove(theKey);

    ParsedSettingsMap::const_iterator j = const_cast<const ParsedSettingsMap *>(&confFile->originalKeys)->lowerBound(prefix);
    while (j != confFile->originalKeys.constEnd() && j.key().startsWith(prefix)) {
        confFile->removedKeys.insert(j.key(), QVariant());
        ++j;
    }
    if (confFile->originalKeys.contains(theKey))
        confFile->removedKeys.insert(theKey, QVariant());
}

void QConfFileSettingsPrivate::set(const QString &key, const QVariant &value)
{
    QConfFile *confFile = confFiles[spec].data();
    if (!confFile)
        return;

    QSettingsKey theKey(key, caseSensitivity, nextPosition++);
    QMutexLocker locker(&confFile->mutex);
    confFile->removedKeys.remove(theKey);
    confFile->addedKeys.insert(theKey, value);
}

bool QConfFileSettingsPrivate::get(const QString &key, QVariant *value) const
{
    QSettingsKey theKey(key, caseSensitivity);
    ParsedSettingsMap::const_iterator j;
    bool found = false;

    for (int i = 0; i < NumConfFiles; ++i) {
        if (QConfFile *confFile = confFiles[i].data()) {
            QMutexLocker locker(&confFile->mutex);

            if (!confFile->addedKeys.isEmpty()) {
                j = confFile->addedKeys.constFind(theKey);
                found = (j != confFile->addedKeys.constEnd());
            }
            if (!found) {
                ensureSectionParsed(confFile, theKey);
                j = confFile->originalKeys.constFind(theKey);
                found = (j != confFile->originalKeys.constEnd()
                         && !confFile->removedKeys.contains(theKey));
            }

            if (found && value)
                *value = *j;

            if (found)
                return true;
            if (!fallbacks)
                break;
        }
    }
    return false;
}

QStringList QConfFileSettingsPrivate::children(const QString &prefix, ChildSpec spec) const
{
    QMap<QString, QString> result;
    ParsedSettingsMap::const_iterator j;

    QSettingsKey thePrefix(prefix, caseSensitivity);
    int startPos = prefix.size();

    for (int i = 0; i < NumConfFiles; ++i) {
        if (QConfFile *confFile = confFiles[i].data()) {
            QMutexLocker locker(&confFile->mutex);

            if (thePrefix.isEmpty()) {
                ensureAllSectionsParsed(confFile);
            } else {
                ensureSectionParsed(confFile, thePrefix);
            }

            j = const_cast<const ParsedSettingsMap *>(
                    &confFile->originalKeys)->lowerBound( thePrefix);
            while (j != confFile->originalKeys.constEnd() && j.key().startsWith(thePrefix)) {
                if (!confFile->removedKeys.contains(j.key()))
                    processChild(j.key().originalCaseKey().mid(startPos), spec, result);
                ++j;
            }

            j = const_cast<const ParsedSettingsMap *>(
                    &confFile->addedKeys)->lowerBound(thePrefix);
            while (j != confFile->addedKeys.constEnd() && j.key().startsWith(thePrefix)) {
                processChild(j.key().originalCaseKey().mid(startPos), spec, result);
                ++j;
            }

            if (!fallbacks)
                break;
        }
    }
    return result.keys();
}

void QConfFileSettingsPrivate::clear()
{
    QConfFile *confFile = confFiles[spec].data();
    if (!confFile)
        return;

    QMutexLocker locker(&confFile->mutex);
    ensureAllSectionsParsed(confFile);
    confFile->addedKeys.clear();
    confFile->removedKeys = confFile->originalKeys;
}

void QConfFileSettingsPrivate::sync()
{
    // people probably won't be checking the status a whole lot, so in case of
    // error we just try to go on and make the best of it

    for (int i = 0; i < NumConfFiles; ++i) {
        QConfFile *confFile = confFiles[i].data();
        if (confFile) {
            QMutexLocker locker(&confFile->mutex);
            syncConfFile(i);
        }
    }
}

void QConfFileSettingsPrivate::flush()
{
    sync();
}

QString QConfFileSettingsPrivate::fileName() const
{
    QConfFile *confFile = confFiles[spec].data();
    if (!confFile)
        return QString();
    return confFile->name;
}

bool QConfFileSettingsPrivate::isWritable() const
{
    if (format > QSettings::IniFormat && !writeFunc)
        return false;

    QConfFile *confFile = confFiles[spec].data();
    if (!confFile)
        return false;

    return confFile->isWritable();
}

void QConfFileSettingsPrivate::syncConfFile(int confFileNo)
{
    QConfFile *confFile = confFiles[confFileNo].data();
    bool readOnly = confFile->addedKeys.isEmpty() && confFile->removedKeys.isEmpty();
    bool ok;

    /*
        We can often optimize the read-only case, if the file on disk
        hasn't changed.
    */
    if (readOnly && confFile->size > 0) {
        QFileInfo fileInfo(confFile->name);
        if (confFile->size == fileInfo.size() && confFile->timeStamp == fileInfo.lastModified())
            return;
    }

    /*
        Open the configuration file and try to use it using a named
        semaphore on Windows and an advisory lock on Unix-based
        systems. This protect us against other QSettings instances
        trying to access the same file from other threads or
        processes.

        As it stands now, the locking mechanism doesn't work for
        .plist files.
    */
    QFile file(confFile->name);
    bool createFile = !file.exists();
    if (!readOnly && confFile->isWritable())
        file.open(QFile::ReadWrite);
    if (!file.isOpen())
        file.open(QFile::ReadOnly);

    if (!createFile && !file.isOpen())
        setStatus(QSettings::AccessError);

#ifdef Q_OS_WIN
    HANDLE readSemaphore = 0;
    HANDLE writeSemaphore = 0;
    static const int FileLockSemMax = 50;
    int numReadLocks = readOnly ? 1 : FileLockSemMax;

    if (file.isOpen()) {
        // Acquire the write lock if we will be writing
        if (!readOnly) {
            QString writeSemName = QLatin1String("QSettingsWriteSem ");
            writeSemName.append(file.fileName());

            writeSemaphore = CreateSemaphore(0, 1, 1, reinterpret_cast<const wchar_t *>(writeSemName.utf16()));

            if (writeSemaphore) {
                WaitForSingleObject(writeSemaphore, INFINITE);
            } else {
                setStatus(QSettings::AccessError);
                return;
            }
        }

        // Acquire all the read locks if we will be writing, to make sure nobody
        // reads while we're writing. If we are only reading, acquire a single
        // read lock.
        QString readSemName(QLatin1String("QSettingsReadSem "));
        readSemName.append(file.fileName());

        readSemaphore = CreateSemaphore(0, FileLockSemMax, FileLockSemMax, reinterpret_cast<const wchar_t *>(readSemName.utf16()));

        if (readSemaphore) {
            for (int i = 0; i < numReadLocks; ++i)
                WaitForSingleObject(readSemaphore, INFINITE);
        } else {
            setStatus(QSettings::AccessError);
            if (writeSemaphore != 0) {
                ReleaseSemaphore(writeSemaphore, 1, 0);
                CloseHandle(writeSemaphore);
            }
            return;
        }
    }
#else
    if (file.isOpen())
        unixLock(file.handle(), readOnly ? F_RDLCK : F_WRLCK);
#endif

    // If we have created the file, apply the file perms
    if (file.isOpen()) {
        if (createFile) {
            QFile::Permissions perms = file.permissions() | QFile::ReadOwner | QFile::WriteOwner;
            if (!confFile->userPerms)
                perms |= QFile::ReadGroup | QFile::ReadOther;
            file.setPermissions(perms);
        }
    }

    /*
        We hold the lock. Let's reread the file if it has changed
        since last time we read it.
    */
    QFileInfo fileInfo(confFile->name);
    bool mustReadFile = true;

    if (!readOnly)
        mustReadFile = (confFile->size != fileInfo.size()
                        || (confFile->size != 0 && confFile->timeStamp != fileInfo.lastModified()));

    if (mustReadFile) {
        confFile->unparsedIniSections.clear();
        confFile->originalKeys.clear();

        /*
            Files that we can't read (because of permissions or
            because they don't exist) are treated as empty files.
        */
        if (file.isReadable() && fileInfo.size() != 0) {
#ifdef Q_OS_MAC
            if (format == QSettings::NativeFormat) {
                ok = readPlistFile(confFile->name, &confFile->originalKeys);
            } else
#endif
            {
                if (format <= QSettings::IniFormat) {
                    QByteArray data = file.readAll();
                    ok = readIniFile(data, &confFile->unparsedIniSections);
                } else {
                    if (readFunc) {
                        QSettings::SettingsMap tempNewKeys;
                        ok = readFunc(file, tempNewKeys);

                        if (ok) {
                            QSettings::SettingsMap::const_iterator i = tempNewKeys.constBegin();
                            while (i != tempNewKeys.constEnd()) {
                                confFile->originalKeys.insert(QSettingsKey(i.key(),
                                                                           caseSensitivity),
                                                              i.value());
                                ++i;
                            }
                        }
                    } else {
                        ok = false;
                    }
                }
            }

            if (!ok)
                setStatus(QSettings::FormatError);
        }

        confFile->size = fileInfo.size();
        confFile->timeStamp = fileInfo.lastModified();
    }

    /*
        We also need to save the file. We still hold the file lock,
        so everything is under control.
    */
    if (!readOnly) {
        ensureAllSectionsParsed(confFile);
        ParsedSettingsMap mergedKeys = confFile->mergedKeyMap();

        if (file.isWritable()) {
#ifdef Q_OS_MAC
            if (format == QSettings::NativeFormat) {
                ok = writePlistFile(confFile->name, mergedKeys);
            } else
#endif
            {
                file.seek(0);
                file.resize(0);

                if (format <= QSettings::IniFormat) {
                    ok = writeIniFile(file, mergedKeys);
                    if (!ok) {
                        // try to restore old data; might work if the disk was full and the new data
                        // was larger than the old data
                        file.seek(0);
                        file.resize(0);
                        writeIniFile(file, confFile->originalKeys);
                    }
                } else {
                    if (writeFunc) {
                        QSettings::SettingsMap tempOriginalKeys;

                        ParsedSettingsMap::const_iterator i = mergedKeys.constBegin();
                        while (i != mergedKeys.constEnd()) {
                            tempOriginalKeys.insert(i.key(), i.value());
                            ++i;
                        }
                        ok = writeFunc(file, tempOriginalKeys);
                    } else {
                        ok = false;
                    }
                }
            }
        } else {
            ok = false;
        }

        if (ok) {
            confFile->unparsedIniSections.clear();
            confFile->originalKeys = mergedKeys;
            confFile->addedKeys.clear();
            confFile->removedKeys.clear();

            QFileInfo fileInfo(confFile->name);
            confFile->size = fileInfo.size();
            confFile->timeStamp = fileInfo.lastModified();
        } else {
            setStatus(QSettings::AccessError);
        }
    }

    /*
        Release the file lock.
    */
#ifdef Q_OS_WIN
    if (readSemaphore != 0) {
        ReleaseSemaphore(readSemaphore, numReadLocks, 0);
        CloseHandle(readSemaphore);
    }
    if (writeSemaphore != 0) {
        ReleaseSemaphore(writeSemaphore, 1, 0);
        CloseHandle(writeSemaphore);
    }
#endif
}

enum { Space = 0x1, Special = 0x2 };

static const char charTraits[256] =
{
    // Space: '\t', '\n', '\r', ' '
    // Special: '\n', '\r', '"', ';', '=', '\\'

    0, 0, 0, 0, 0, 0, 0, 0, 0, Space, Space | Special, 0, 0, Space | Special, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    Space, 0, Special, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, Special, 0, Special, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, Special, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};

bool QConfFileSettingsPrivate::readIniLine(const QByteArray &data, int &dataPos,
                                           int &lineStart, int &lineLen, int &equalsPos)
{
    int dataLen = data.length();
    bool inQuotes = false;

    equalsPos = -1;

    lineStart = dataPos;
    while (lineStart < dataLen && (charTraits[uint(uchar(data.at(lineStart)))] & Space))
        ++lineStart;

    int i = lineStart;
    while (i < dataLen) {
        while (!(charTraits[uint(uchar(data.at(i)))] & Special)) {
            if (++i == dataLen)
                goto break_out_of_outer_loop;
        }

        char ch = data.at(i++);
        if (ch == '=') {
            if (!inQuotes && equalsPos == -1)
                equalsPos = i - 1;
        } else if (ch == '\n' || ch == '\r') {
            if (i == lineStart + 1) {
                ++lineStart;
            } else if (!inQuotes) {
                --i;
                goto break_out_of_outer_loop;
            }
        } else if (ch == '\\') {
            if (i < dataLen) {
                char ch = data.at(i++);
                if (i < dataLen) {
                    char ch2 = data.at(i);
                    // \n, \r, \r\n, and \n\r are legitimate line terminators in INI files
                    if ((ch == '\n' && ch2 == '\r') || (ch == '\r' && ch2 == '\n'))
                        ++i;
                }
            }
        } else if (ch == '"') {
            inQuotes = !inQuotes;
        } else {
            Q_ASSERT(ch == ';');

            if (i == lineStart + 1) {
                char ch;
                while (i < dataLen && ((ch = data.at(i) != '\n') && ch != '\r'))
                    ++i;
                lineStart = i;
            } else if (!inQuotes) {
                --i;
                goto break_out_of_outer_loop;
            }
        }
    }

break_out_of_outer_loop:
    dataPos = i;
    lineLen = i - lineStart;
    return lineLen > 0;
}

/*
    Returns false on parse error. However, as many keys are read as
    possible, so if the user doesn't check the status he will get the
    most out of the file anyway.
*/
bool QConfFileSettingsPrivate::readIniFile(const QByteArray &data,
                                           UnparsedSettingsMap *unparsedIniSections)
{
#define FLUSH_CURRENT_SECTION() \
    { \
        QByteArray &sectionData = (*unparsedIniSections)[QSettingsKey(currentSection, \
                                                                      IniCaseSensitivity, \
                                                                      sectionPosition)]; \
        if (!sectionData.isEmpty()) \
            sectionData.append('\n'); \
        sectionData += data.mid(currentSectionStart, lineStart - currentSectionStart); \
        sectionPosition = ++position; \
    }

    QString currentSection;
    int currentSectionStart = 0;
    int dataPos = 0;
    int lineStart;
    int lineLen;
    int equalsPos;
    int position = 0;
    int sectionPosition = 0;
    bool ok = true;

    while (readIniLine(data, dataPos, lineStart, lineLen, equalsPos)) {
        char ch = data.at(lineStart);
        if (ch == '[') {
            FLUSH_CURRENT_SECTION();

            // this is a section
            QByteArray iniSection;
            int idx = data.indexOf(']', lineStart);
            if (idx == -1 || idx >= lineStart + lineLen) {
                ok = false;
                iniSection = data.mid(lineStart + 1, lineLen - 1);
            } else {
                iniSection = data.mid(lineStart + 1, idx - lineStart - 1);
            }

            iniSection = iniSection.trimmed();

            if (qstricmp(iniSection, "general") == 0) {
                currentSection.clear();
            } else {
                if (qstricmp(iniSection, "%general") == 0) {
                    currentSection = QLatin1String(iniSection.constData() + 1);
                } else {
                    currentSection.clear();
                    iniUnescapedKey(iniSection, 0, iniSection.size(), currentSection);
                }
                currentSection += QLatin1Char('/');
            }
            currentSectionStart = dataPos;
        }
        ++position;
    }

    Q_ASSERT(lineStart == data.length());
    FLUSH_CURRENT_SECTION();

    return ok;

#undef FLUSH_CURRENT_SECTION
}

bool QConfFileSettingsPrivate::readIniSection(const QSettingsKey &section, const QByteArray &data,
                                              ParsedSettingsMap *settingsMap, QTextCodec *codec)
{
    QStringList strListValue;
    bool sectionIsLowercase = (section == section.originalCaseKey());
    int equalsPos;

    bool ok = true;
    int dataPos = 0;
    int lineStart;
    int lineLen;
    int position = section.originalKeyPosition();

    while (readIniLine(data, dataPos, lineStart, lineLen, equalsPos)) {
        char ch = data.at(lineStart);
        Q_ASSERT(ch != '[');

        if (equalsPos == -1) {
            if (ch != ';')
                ok = false;
            continue;
        }

        int keyEnd = equalsPos;
        while (keyEnd > lineStart && ((ch = data.at(keyEnd - 1)) == ' ' || ch == '\t'))
            --keyEnd;
        int valueStart = equalsPos + 1;

        QString key = section.originalCaseKey();
        bool keyIsLowercase = (iniUnescapedKey(data, lineStart, keyEnd, key) && sectionIsLowercase);

        QString strValue;
        strValue.reserve(lineLen - (valueStart - lineStart));
        bool isStringList = iniUnescapedStringList(data, valueStart, lineStart + lineLen,
                                                   strValue, strListValue, codec);
        QVariant variant;
        if (isStringList) {
            variant = stringListToVariantList(strListValue);
        } else {
            variant = stringToVariant(strValue);
        }

        /*
            We try to avoid the expensive toLower() call in
            QSettingsKey by passing Qt::CaseSensitive when the
            key is already in lowercase.
        */
        settingsMap->insert(QSettingsKey(key, keyIsLowercase ? Qt::CaseSensitive
                                                             : IniCaseSensitivity,
                                         position),
                            variant);
        ++position;
    }

    return ok;
}

class QSettingsIniKey : public QString
{
public:
    inline QSettingsIniKey() : position(-1) {}
    inline QSettingsIniKey(const QString &str, int pos = -1) : QString(str), position(pos) {}

    int position;
};

static bool operator<(const QSettingsIniKey &k1, const QSettingsIniKey &k2)
{
    if (k1.position != k2.position)
        return k1.position < k2.position;
    return static_cast<const QString &>(k1) < static_cast<const QString &>(k2);
}

typedef QMap<QSettingsIniKey, QVariant> IniKeyMap;

struct QSettingsIniSection
{
    int position;
    IniKeyMap keyMap;

    inline QSettingsIniSection() : position(-1) {}
};

typedef QMap<QString, QSettingsIniSection> IniMap;

/*
    This would be more straightforward if we didn't try to remember the original
    key order in the .ini file, but we do.
*/
bool QConfFileSettingsPrivate::writeIniFile(QIODevice &device, const ParsedSettingsMap &map)
{
    IniMap iniMap;
    IniMap::const_iterator i;

#ifdef Q_OS_WIN
    const char * const eol = "\r\n";
#else
    const char eol = '\n';
#endif

    for (ParsedSettingsMap::const_iterator j = map.constBegin(); j != map.constEnd(); ++j) {
        QString section;
        QSettingsIniKey key(j.key().originalCaseKey(), j.key().originalKeyPosition());
        int slashPos;

        if ((slashPos = key.indexOf(QLatin1Char('/'))) != -1) {
            section = key.left(slashPos);
            key.remove(0, slashPos + 1);
        }

        QSettingsIniSection &iniSection = iniMap[section];

        // -1 means infinity
        if (uint(key.position) < uint(iniSection.position))
            iniSection.position = key.position;
        iniSection.keyMap[key] = j.value();
    }

    const int sectionCount = iniMap.size();
    QVector<QSettingsIniKey> sections;
    sections.reserve(sectionCount);
    for (i = iniMap.constBegin(); i != iniMap.constEnd(); ++i)
        sections.append(QSettingsIniKey(i.key(), i.value().position));
    qSort(sections);

    bool writeError = false;
    for (int j = 0; !writeError && j < sectionCount; ++j) {
        i = iniMap.constFind(sections.at(j));
        Q_ASSERT(i != iniMap.constEnd());

        QByteArray realSection;

        iniEscapedKey(i.key(), realSection);

        if (realSection.isEmpty()) {
            realSection = "[General]";
        } else if (qstricmp(realSection, "general") == 0) {
            realSection = "[%General]";
        } else {
            realSection.prepend('[');
            realSection.append(']');
        }

        if (j != 0)
            realSection.prepend(eol);
        realSection += eol;

        device.write(realSection);

        const IniKeyMap &ents = i.value().keyMap;
        for (IniKeyMap::const_iterator j = ents.constBegin(); j != ents.constEnd(); ++j) {
            QByteArray block;
            iniEscapedKey(j.key(), block);
            block += '=';

            const QVariant &value = j.value();

            /*
                The size() != 1 trick is necessary because
                QVariant(QString("foo")).toList() returns an empty
                list, not a list containing "foo".
            */
            if (value.type() == QVariant::StringList
                    || (value.type() == QVariant::List && value.toList().size() != 1)) {
                iniEscapedStringList(variantListToStringList(value.toList()), block, iniCodec);
            } else {
                iniEscapedString(variantToString(value), block, iniCodec);
            }
            block += eol;
            if (device.write(block) == -1) {
                writeError = true;
                break;
            }
        }
    }
    return !writeError;
}

void QConfFileSettingsPrivate::ensureAllSectionsParsed(QConfFile *confFile) const
{
    UnparsedSettingsMap::const_iterator i = confFile->unparsedIniSections.constBegin();
    const UnparsedSettingsMap::const_iterator end = confFile->unparsedIniSections.constEnd();

    for (; i != end; ++i) {
        if (!QConfFileSettingsPrivate::readIniSection(i.key(), i.value(), &confFile->originalKeys, iniCodec))
            setStatus(QSettings::FormatError);
    }
    confFile->unparsedIniSections.clear();
}

void QConfFileSettingsPrivate::ensureSectionParsed(QConfFile *confFile,
                                                   const QSettingsKey &key) const
{
    if (confFile->unparsedIniSections.isEmpty())
        return;

    UnparsedSettingsMap::iterator i;

    int indexOfSlash = key.indexOf(QLatin1Char('/'));
    if (indexOfSlash != -1) {
        i = confFile->unparsedIniSections.upperBound(key);
        if (i == confFile->unparsedIniSections.begin())
            return;
        --i;
        if (i.key().isEmpty() || !key.startsWith(i.key()))
            return;
    } else {
        i = confFile->unparsedIniSections.begin();
        if (i == confFile->unparsedIniSections.end() || !i.key().isEmpty())
            return;
    }

    if (!QConfFileSettingsPrivate::readIniSection(i.key(), i.value(), &confFile->originalKeys, iniCodec))
        setStatus(QSettings::FormatError);
    confFile->unparsedIniSections.erase(i);
}

#ifndef QT_NO_QOBJECT

QSettings::QSettings(const QString &organization, const QString &application, QObject *parent)
    : QObject(*QSettingsPrivate::create(NativeFormat, UserScope, organization, application),
              parent)
{
}

QSettings::QSettings(Scope scope, const QString &organization, const QString &application,
                     QObject *parent)
    : QObject(*QSettingsPrivate::create(NativeFormat, scope, organization, application), parent)
{
}

QSettings::QSettings(Format format, Scope scope, const QString &organization,
                     const QString &application, QObject *parent)
    : QObject(*QSettingsPrivate::create(format, scope, organization, application), parent)
{
}

QSettings::QSettings(const QString &fileName, Format format, QObject *parent)
    : QObject(*QSettingsPrivate::create(fileName, format), parent)
{
}

QSettings::QSettings(QObject *parent)
    : QObject(*QSettingsPrivate::create(globalDefaultFormat, UserScope,
#ifdef Q_OS_MAC
                                        QCoreApplication::organizationDomain().isEmpty()
                                            ? QCoreApplication::organizationName()
                                            : QCoreApplication::organizationDomain()
#else
                                        QCoreApplication::organizationName().isEmpty()
                                            ? QCoreApplication::organizationDomain()
                                            : QCoreApplication::organizationName()
#endif
                                        , QCoreApplication::applicationName()),
              parent)
{
}

#else
QSettings::QSettings(const QString &organization, const QString &application)
    : d_ptr(QSettingsPrivate::create(globalDefaultFormat, QSettings::UserScope, organization, application))
{
    d_ptr->q_ptr = this;
}

QSettings::QSettings(Scope scope, const QString &organization, const QString &application)
    : d_ptr(QSettingsPrivate::create(globalDefaultFormat, scope, organization, application))
{
    d_ptr->q_ptr = this;
}

QSettings::QSettings(Format format, Scope scope, const QString &organization,
                     const QString &application)
    : d_ptr(QSettingsPrivate::create(format, scope, organization, application))
{
    d_ptr->q_ptr = this;
}

QSettings::QSettings(const QString &fileName, Format format)
    : d_ptr(QSettingsPrivate::create(fileName, format))
{
    d_ptr->q_ptr = this;
}
#endif

QSettings::~QSettings()
{
    Q_D(QSettings);
    if (d->pendingChanges) {
        QT_TRY {
            d->flush();
        } QT_CATCH(...) {
            ; // ok. then don't flush but at least don't throw in the destructor
        }
    }
}

void QSettings::clear()
{
    Q_D(QSettings);
    d->clear();
    d->requestUpdate();
}

void QSettings::sync()
{
    Q_D(QSettings);
    d->sync();
}

QString QSettings::fileName() const
{
    Q_D(const QSettings);
    return d->fileName();
}

QSettings::Format QSettings::format() const
{
    Q_D(const QSettings);
    return d->format;
}

QSettings::Scope QSettings::scope() const
{
    Q_D(const QSettings);
    return d->scope;
}

QString QSettings::organizationName() const
{
    Q_D(const QSettings);
    return d->organizationName;
}

QString QSettings::applicationName() const
{
    Q_D(const QSettings);
    return d->applicationName;
}

#ifndef QT_NO_TEXTCODEC

void QSettings::setIniCodec(QTextCodec *codec)
{
    Q_D(QSettings);
    d->iniCodec = codec;
}

void QSettings::setIniCodec(const char *codecName)
{
    Q_D(QSettings);
    if (QTextCodec *codec = QTextCodec::codecForName(codecName))
        d->iniCodec = codec;
}

QTextCodec *QSettings::iniCodec() const
{
    Q_D(const QSettings);
    return d->iniCodec;
}

#endif // QT_NO_TEXTCODEC

QSettings::Status QSettings::status() const
{
    Q_D(const QSettings);
    return d->status;
}

void QSettings::beginGroup(const QString &prefix)
{
    Q_D(QSettings);
    d->beginGroupOrArray(QSettingsGroup(d->normalizedKey(prefix)));
}

void QSettings::endGroup()
{
    Q_D(QSettings);
    if (d->groupStack.isEmpty()) {
        qWarning("QSettings::endGroup: No matching beginGroup()");
        return;
    }

    QSettingsGroup group = d->groupStack.pop();
    int len = group.toString().size();
    if (len > 0)
        d->groupPrefix.truncate(d->groupPrefix.size() - (len + 1));

    if (group.isArray())
        qWarning("QSettings::endGroup: Expected endArray() instead");
}

QString QSettings::group() const
{
    Q_D(const QSettings);
    return d->groupPrefix.left(d->groupPrefix.size() - 1);
}

int QSettings::beginReadArray(const QString &prefix)
{
    Q_D(QSettings);
    d->beginGroupOrArray(QSettingsGroup(d->normalizedKey(prefix), false));
    return value(QLatin1String("size")).toInt();
}

void QSettings::beginWriteArray(const QString &prefix, int size)
{
    Q_D(QSettings);
    d->beginGroupOrArray(QSettingsGroup(d->normalizedKey(prefix), size < 0));

    if (size < 0)
        remove(QLatin1String("size"));
    else
        setValue(QLatin1String("size"), size);
}

void QSettings::endArray()
{
    Q_D(QSettings);
    if (d->groupStack.isEmpty()) {
        qWarning("QSettings::endArray: No matching beginArray()");
        return;
    }

    QSettingsGroup group = d->groupStack.top();
    int len = group.toString().size();
    d->groupStack.pop();
    if (len > 0)
        d->groupPrefix.truncate(d->groupPrefix.size() - (len + 1));

    if (group.arraySizeGuess() != -1)
        setValue(group.name() + QLatin1String("/size"), group.arraySizeGuess());

    if (!group.isArray())
        qWarning("QSettings::endArray: Expected endGroup() instead");
}

void QSettings::setArrayIndex(int i)
{
    Q_D(QSettings);
    if (d->groupStack.isEmpty() || !d->groupStack.top().isArray()) {
        qWarning("QSettings::setArrayIndex: Missing beginArray()");
        return;
    }

    QSettingsGroup &top = d->groupStack.top();
    int len = top.toString().size();
    top.setArrayIndex(qMax(i, 0));
    d->groupPrefix.replace(d->groupPrefix.size() - len - 1, len, top.toString());
}

QStringList QSettings::allKeys() const
{
    Q_D(const QSettings);
    return d->children(d->groupPrefix, QSettingsPrivate::AllKeys);
}

QStringList QSettings::childKeys() const
{
    Q_D(const QSettings);
    return d->children(d->groupPrefix, QSettingsPrivate::ChildKeys);
}

QStringList QSettings::childGroups() const
{
    Q_D(const QSettings);
    return d->children(d->groupPrefix, QSettingsPrivate::ChildGroups);
}

bool QSettings::isWritable() const
{
    Q_D(const QSettings);
    return d->isWritable();
}

void QSettings::setValue(const QString &key, const QVariant &value)
{
    Q_D(QSettings);
    QString k = d->actualKey(key);
    d->set(k, value);
    d->requestUpdate();
}

void QSettings::remove(const QString &key)
{
    Q_D(QSettings);
    /*
        We cannot use actualKey(), because remove() supports empty
        keys. The code is also tricky because of slash handling.
    */
    QString theKey = d->normalizedKey(key);
    if (theKey.isEmpty())
        theKey = group();
    else
        theKey.prepend(d->groupPrefix);

    if (theKey.isEmpty()) {
        d->clear();
    } else {
        d->remove(theKey);
    }
    d->requestUpdate();
}

bool QSettings::contains(const QString &key) const
{
    Q_D(const QSettings);
    QString k = d->actualKey(key);
    return d->get(k, 0);
}

void QSettings::setFallbacksEnabled(bool b)
{
    Q_D(QSettings);
    d->fallbacks = !!b;
}

bool QSettings::fallbacksEnabled() const
{
    Q_D(const QSettings);
    return d->fallbacks;
}

#ifndef QT_NO_QOBJECT

bool QSettings::event(QEvent *event)
{
    Q_D(QSettings);
    if (event->type() == QEvent::UpdateRequest) {
        d->update();
        return true;
    }
    return QObject::event(event);
}
#endif

QVariant QSettings::value(const QString &key, const QVariant &defaultValue) const
{
    Q_D(const QSettings);
    QVariant result = defaultValue;
    QString k = d->actualKey(key);
    d->get(k, &result);
    return result;
}

void QSettings::setDefaultFormat(Format format)
{
    globalDefaultFormat = format;
}

QSettings::Format QSettings::defaultFormat()
{
    return globalDefaultFormat;
}

void QSettings::setSystemIniPath(const QString &dir)
{
    setPath(IniFormat, SystemScope, dir);
#if !defined(Q_OS_WIN) && !defined(Q_OS_MAC)
    setPath(NativeFormat, SystemScope, dir);
#endif
}

void QSettings::setUserIniPath(const QString &dir)
{
    setPath(IniFormat, UserScope, dir);
#if !defined(Q_OS_WIN) && !defined(Q_OS_MAC)
    setPath(NativeFormat, UserScope, dir);
#endif
}

void QSettings::setPath(Format format, Scope scope, const QString &path)
{
    QMutexLocker locker(globalMutex());
    PathHash *pathHash = pathHashFunc();
    if (pathHash->isEmpty())
        initDefaultPaths(&locker);
    pathHash->insert(pathHashKey(format, scope), path + QDir::separator());
}

QSettings::Format QSettings::registerFormat(const QString &extension, ReadFunc readFunc,
                                            WriteFunc writeFunc,
                                            Qt::CaseSensitivity caseSensitivity)
{
#ifdef QT_QSETTINGS_ALWAYS_CASE_SENSITIVE_AND_FORGET_ORIGINAL_KEY_ORDER
    Q_ASSERT(caseSensitivity == Qt::CaseSensitive);
#endif

    QMutexLocker locker(globalMutex());
    CustomFormatVector *customFormatVector = customFormatVectorFunc();
    int index = customFormatVector->size();
    if (index == 16) // the QSettings::Format enum has room for 16 custom formats
        return QSettings::InvalidFormat;

    QConfFileCustomFormat info;
    info.extension = QLatin1Char('.');
    info.extension += extension;
    info.readFunc = readFunc;
    info.writeFunc = writeFunc;
    info.caseSensitivity = caseSensitivity;
    customFormatVector->append(info);

    return QSettings::Format((int)QSettings::CustomFormat1 + index);
}

#ifdef QT3_SUPPORT
void QSettings::setPath_helper(Scope scope, const QString &organization, const QString &application)
{
    Q_D(QSettings);
    if (d->pendingChanges)
        d->flush();
    QSettingsPrivate *oldPriv = d;
    QSettingsPrivate *newPriv = QSettingsPrivate::create(oldPriv->format, scope, organization, application);
    static_cast<QObjectPrivate &>(*newPriv) = static_cast<QObjectPrivate &>(*oldPriv);  // copy the QObject stuff over (hack)
    oldPriv->threadData = 0; //     QTBUG-36908, newPriv takes ownership.
    d_ptr.reset(newPriv);
}

#endif

QT_END_NAMESPACE

#endif // QT_NO_SETTINGS