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//#define QTEXTSTREAM_DEBUG

static const int QTEXTSTREAM_BUFFERSIZE = 16384;

/*!

    \class QTextStream

    \brief The QTextStream class provides a convenient interface for

    reading and writing text.

    \ingroup io

    \ingroup string-processing

    \reentrant

    QTextStream can operate on a QIODevice, a QByteArray or a

    QString. Using QTextStream's streaming operators, you can

    conveniently read and write words, lines and numbers. For

    generating text, QTextStream supports formatting options for field

    padding and alignment, and formatting of numbers. Example:

    \snippet doc/src/snippets/code/src_corelib_io_qtextstream.cpp 0

    It's also common to use QTextStream to read console input and write

    console output. QTextStream is locale aware, and will automatically decode

    standard input using the correct codec. Example:

    \snippet doc/src/snippets/code/src_corelib_io_qtextstream.cpp 1

    Note that you cannot use QTextStream::atEnd(), which returns true when you

    have reached the end of the data stream, with stdin. The reason for this is

    that as long as stdin doesn't give any input to the QTextStream, \c atEnd()

    will return true even if the stdin is open and waiting for more characters.

    Besides using QTextStream's constructors, you can also set the

    device or string QTextStream operates on by calling setDevice() or

    setString(). You can seek to a position by calling seek(), and

    atEnd() will return true when there is no data left to be read. If

    you call flush(), QTextStream will empty all data from its write

    buffer into the device and call flush() on the device.

    Internally, QTextStream uses a Unicode based buffer, and

    QTextCodec is used by QTextStream to automatically support

    different character sets. By default, QTextCodec::codecForLocale()

    is used for reading and writing, but you can also set the codec by

    calling setCodec(). Automatic Unicode detection is also

    supported. When this feature is enabled (the default behavior),

    QTextStream will detect the UTF-16 or the UTF-32 BOM (Byte Order Mark) and

    switch to the appropriate UTF codec when reading. QTextStream

    does not write a BOM by default, but you can enable this by calling

    setGenerateByteOrderMark(true). When QTextStream operates on a QString

    directly, the codec is disabled.

    There are three general ways to use QTextStream when reading text

    files:

    \list

    \o Chunk by chunk, by calling readLine() or readAll().

    \o Word by word. QTextStream supports streaming into QStrings,

    QByteArrays and char* buffers. Words are delimited by space, and

    leading white space is automatically skipped.

    \o Character by character, by streaming into QChar or char types.

    This method is often used for convenient input handling when

    parsing files, independent of character encoding and end-of-line

    semantics. To skip white space, call skipWhiteSpace().

    \endlist

    Since the text stream uses a buffer, you should not read from

    the stream using the implementation of a superclass. For instance,

    if you have a QFile and read from it directly using

    QFile::readLine() instead of using the stream, the text stream's

    internal position will be out of sync with the file's position.

    By default, when reading numbers from a stream of text,

    QTextStream will automatically detect the number's base

    representation. For example, if the number starts with "0x", it is

    assumed to be in hexadecimal form. If it starts with the digits

    1-9, it is assumed to be in decimal form, and so on. You can set

    the integer base, thereby disabling the automatic detection, by

    calling setIntegerBase(). Example:

    \snippet doc/src/snippets/code/src_corelib_io_qtextstream.cpp 2

    QTextStream supports many formatting options for generating text.

    You can set the field width and pad character by calling

    setFieldWidth() and setPadChar(). Use setFieldAlignment() to set

    the alignment within each field. For real numbers, call

    setRealNumberNotation() and setRealNumberPrecision() to set the

    notation (SmartNotation, ScientificNotation, FixedNotation) and precision in

    digits of the generated number. Some extra number formatting

    options are also available through setNumberFlags().

    \keyword QTextStream manipulators

    Like \c <iostream> in the standard C++ library, QTextStream also

    defines several global manipulator functions:

    \table

    \header \o Manipulator        \o Description

    \row    \o \c bin             \o Same as setIntegerBase(2).

    \row    \o \c oct             \o Same as setIntegerBase(8).

    \row    \o \c dec             \o Same as setIntegerBase(10).

    \row    \o \c hex             \o Same as setIntegerBase(16).

    \row    \o \c showbase        \o Same as setNumberFlags(numberFlags() | ShowBase).

    \row    \o \c forcesign       \o Same as setNumberFlags(numberFlags() | ForceSign).

    \row    \o \c forcepoint      \o Same as setNumberFlags(numberFlags() | ForcePoint).

    \row    \o \c noshowbase      \o Same as setNumberFlags(numberFlags() & ~ShowBase).

    \row    \o \c noforcesign     \o Same as setNumberFlags(numberFlags() & ~ForceSign).

    \row    \o \c noforcepoint    \o Same as setNumberFlags(numberFlags() & ~ForcePoint).

    \row    \o \c uppercasebase   \o Same as setNumberFlags(numberFlags() | UppercaseBase).

    \row    \o \c uppercasedigits \o Same as setNumberFlags(numberFlags() | UppercaseDigits).

    \row    \o \c lowercasebase   \o Same as setNumberFlags(numberFlags() & ~UppercaseBase).

    \row    \o \c lowercasedigits \o Same as setNumberFlags(numberFlags() & ~UppercaseDigits).

    \row    \o \c fixed           \o Same as setRealNumberNotation(FixedNotation).

    \row    \o \c scientific      \o Same as setRealNumberNotation(ScientificNotation).

    \row    \o \c left            \o Same as setFieldAlignment(AlignLeft).

    \row    \o \c right           \o Same as setFieldAlignment(AlignRight).

    \row    \o \c center          \o Same as setFieldAlignment(AlignCenter).

    \row    \o \c endl            \o Same as operator<<('\n') and flush().

    \row    \o \c flush           \o Same as flush().

    \row    \o \c reset           \o Same as reset().

    \row    \o \c ws              \o Same as skipWhiteSpace().

    \row    \o \c bom             \o Same as setGenerateByteOrderMark(true).

    \endtable

    In addition, Qt provides three global manipulators that take a

    parameter: qSetFieldWidth(), qSetPadChar(), and

    qSetRealNumberPrecision().

    \sa QDataStream, QIODevice, QFile, QBuffer, QTcpSocket, {Codecs Example}

*/

/*! \enum QTextStream::RealNumberNotation

    This enum specifies which notations to use for expressing \c

    float and \c double as strings.

    \value ScientificNotation Scientific notation (\c{printf()}'s \c %e flag).

    \value FixedNotation Fixed-point notation (\c{printf()}'s \c %f flag).

    \value SmartNotation Scientific or fixed-point notation, depending on which makes most sense (\c{printf()}'s \c %g flag).

    \sa setRealNumberNotation()

*/

/*! \enum QTextStream::FieldAlignment

    This enum specifies how to align text in fields when the field is

    wider than the text that occupies it.

    \value AlignLeft  Pad on the right side of fields.

    \value AlignRight  Pad on the left side of fields.

    \value AlignCenter  Pad on both sides of field.

    \value AlignAccountingStyle  Same as AlignRight, except that the

                                 sign of a number is flush left.

    \sa setFieldAlignment()

*/

/*! \enum QTextStream::NumberFlag

    This enum specifies various flags that can be set to affect the

    output of integers, \c{float}s, and \c{double}s.

    \value ShowBase  Show the base as a prefix if the base

                     is 16 ("0x"), 8 ("0"), or 2 ("0b").

    \value ForcePoint  Always put the decimal separator in numbers, even if

                       there are no decimals.

    \value ForceSign  Always put the sign in numbers, even for positive numbers.

    \value UppercaseBase  Use uppercase versions of base prefixes ("0X", "0B").

    \value UppercaseDigits  Use uppercase letters for expressing

                            digits 10 to 35 instead of lowercase.

    \sa setNumberFlags()

*/

/*! \enum QTextStream::Status

    This enum describes the current status of the text stream.

    \value Ok               The text stream is operating normally.

    \value ReadPastEnd      The text stream has read past the end of the

                            data in the underlying device.

    \value ReadCorruptData  The text stream has read corrupt data.

    \sa status()

*/

#include "qtextstream.h"

#include "qbuffer.h"

#include "qfile.h"

#include "qnumeric.h"

#ifndef QT_NO_TEXTCODEC

#include "qtextcodec.h"

#endif

#ifndef Q_OS_WINCE

#include <locale.h>

#endif

#include "private/qlocale_p.h"

#include <stdlib.h>

#include <limits.h>

#include <new>

#if defined QTEXTSTREAM_DEBUG

#include <ctype.h>

QT_BEGIN_NAMESPACE

// Returns a human readable representation of the first \a len

// characters in \a data.

static QByteArray qt_prettyDebug(const char *data, int len, int maxSize)

{

    if (!data) return "(null)";

    QByteArray out;

    for (int i = 0; i < len; ++i) {

        char c = data[i];

        if (isprint(int(uchar(c)))) {

            out += c;

        } else switch (c) {

        case '\n': out += "\\n"; break;

        case '\r': out += "\\r"; break;

        case '\t': out += "\\t"; break;

        default:

            QString tmp;

            tmp.sprintf("\\x%x", (unsigned int)(unsigned char)c);

            out += tmp.toLatin1();

        }

    }

    if (len < maxSize)

        out += "...";

    return out;

}

QT_END_NAMESPACE

#endif

// A precondition macro

#define Q_VOID

#define CHECK_VALID_STREAM(x) do { \

    if (!d->string && !d->device) { \

        qWarning("QTextStream: No device"); \

        return x; \

    } } while (0)

// Base implementations of operator>> for ints and reals

#define IMPLEMENT_STREAM_RIGHT_INT_OPERATOR(type) do { \

    Q_D(QTextStream); \

    CHECK_VALID_STREAM(*this); \

    qulonglong tmp; \

    switch (d->getNumber(&tmp)) { \

    case QTextStreamPrivate::npsOk: \

        i = (type)tmp; \

        break; \

    case QTextStreamPrivate::npsMissingDigit: \

    case QTextStreamPrivate::npsInvalidPrefix: \

        i = (type)0; \

        setStatus(atEnd() ? QTextStream::ReadPastEnd : QTextStream::ReadCorruptData); \

        break; \

    } \

    return *this; } while (0)

#define IMPLEMENT_STREAM_RIGHT_REAL_OPERATOR(type) do { \

    Q_D(QTextStream); \

    CHECK_VALID_STREAM(*this); \

    double tmp; \

    if (d->getReal(&tmp)) { \

        f = (type)tmp; \

    } else { \

        f = (type)0; \

        setStatus(atEnd() ? QTextStream::ReadPastEnd : QTextStream::ReadCorruptData); \

    } \

    return *this; } while (0)

QT_BEGIN_NAMESPACE

#ifndef QT_NO_QOBJECT

class QDeviceClosedNotifier : public QObject

{

    Q_OBJECT

public:

    inline QDeviceClosedNotifier()

    { }

    inline void setupDevice(QTextStream *stream, QIODevice *device)

    {

        disconnect();

        if (device)

            connect(device, SIGNAL(aboutToClose()), this, SLOT(flushStream()));

        this->stream = stream;

    }

public Q_SLOTS:

    inline void flushStream() { stream->flush(); }

private:

    QTextStream *stream;

};

#endif

//-------------------------------------------------------------------

class QTextStreamPrivate

{

    Q_DECLARE_PUBLIC(QTextStream)

public:

    QTextStreamPrivate(QTextStream *q_ptr);

    ~QTextStreamPrivate();

    void reset();

    // device

    QIODevice *device;

#ifndef QT_NO_QOBJECT

    QDeviceClosedNotifier deviceClosedNotifier;

#endif

    bool deleteDevice;

    // string

    QString *string;

    int stringOffset;

    QIODevice::OpenMode stringOpenMode;

#ifndef QT_NO_TEXTCODEC

    // codec

    QTextCodec *codec;

    QTextCodec::ConverterState readConverterState;

    QTextCodec::ConverterState writeConverterState;

    QTextCodec::ConverterState *readConverterSavedState;

    bool autoDetectUnicode;

#endif

    // i/o

    enum TokenDelimiter {

        Space,

        NotSpace,

        EndOfLine

    };

    QString read(int maxlen);

    bool scan(const QChar **ptr, int *tokenLength,

              int maxlen, TokenDelimiter delimiter);

    inline const QChar *readPtr() const;

    inline void consumeLastToken();

    inline void consume(int nchars);

    void saveConverterState(qint64 newPos);

    void restoreToSavedConverterState();

    int lastTokenSize;

    // Return value type for getNumber()

    enum NumberParsingStatus {

        npsOk,

        npsMissingDigit,

        npsInvalidPrefix

    };

    inline bool write(const QString &data);

    inline bool getChar(QChar *ch);

    inline void ungetChar(const QChar &ch);

    NumberParsingStatus getNumber(qulonglong *l);

    bool getReal(double *f);

    bool putNumber(qulonglong number, bool negative);

    inline bool putString(const QString &ch, bool number = false);

    // buffers

    bool fillReadBuffer(qint64 maxBytes = -1);

    void resetReadBuffer();

    bool flushWriteBuffer();

    QString writeBuffer;

    QString readBuffer;

    int readBufferOffset;

    int readConverterSavedStateOffset; //the offset between readBufferStartDevicePos and that start of the buffer

    qint64 readBufferStartDevicePos;

    // streaming parameters

    int realNumberPrecision;

    int integerBase;

    int fieldWidth;

    QChar padChar;

    QTextStream::FieldAlignment fieldAlignment;

    QTextStream::RealNumberNotation realNumberNotation;

    QTextStream::NumberFlags numberFlags;

    // status

    QTextStream::Status status;

    QLocale locale;

    QTextStream *q_ptr;

};

/*! \internal

*/

QTextStreamPrivate::QTextStreamPrivate(QTextStream *q_ptr)

    :

#ifndef QT_NO_TEXTCODEC

    readConverterSavedState(0),

#endif

    readConverterSavedStateOffset(0),

    locale(QLocale::C)

{

    this->q_ptr = q_ptr;

    reset();

}

/*! \internal

*/

QTextStreamPrivate::~QTextStreamPrivate()

{

    if (deleteDevice) {

#ifndef QT_NO_QOBJECT

        device->blockSignals(true);

#endif

        delete device;

    }

#ifndef QT_NO_TEXTCODEC

    delete readConverterSavedState;

#endif

}

#ifndef QT_NO_TEXTCODEC

static void resetCodecConverterStateHelper(QTextCodec::ConverterState *state)

{

    state->~ConverterState();

    new (state) QTextCodec::ConverterState;

}

static void copyConverterStateHelper(QTextCodec::ConverterState *dest,

    const QTextCodec::ConverterState *src)

{

    // ### QTextCodec::ConverterState's copy constructors and assignments are

    // private. This function copies the structure manually.

    Q_ASSERT(!src->d);

    dest->flags = src->flags;

    dest->invalidChars = src->invalidChars;

    dest->state_data[0] = src->state_data[0];

    dest->state_data[1] = src->state_data[1];

    dest->state_data[2] = src->state_data[2];

}

#endif

/*! \internal

*/

void QTextStreamPrivate::reset()

{

    realNumberPrecision = 6;

    integerBase = 0;

    fieldWidth = 0;

    padChar = QLatin1Char(' ');

    fieldAlignment = QTextStream::AlignRight;

    realNumberNotation = QTextStream::SmartNotation;

    numberFlags = 0;

    device = 0;

    deleteDevice = false;

    string = 0;

    stringOffset = 0;

    stringOpenMode = QIODevice::NotOpen;

    readBufferOffset = 0;

    readBufferStartDevicePos = 0;

    lastTokenSize = 0;

#ifndef QT_NO_TEXTCODEC

    codec = QTextCodec::codecForLocale();

    resetCodecConverterStateHelper(&readConverterState);

    resetCodecConverterStateHelper(&writeConverterState);

    delete readConverterSavedState;

    readConverterSavedState = 0;

    writeConverterState.flags |= QTextCodec::IgnoreHeader;

    autoDetectUnicode = true;

#endif

}

/*! \internal

*/

bool QTextStreamPrivate::fillReadBuffer(qint64 maxBytes)

{

    // no buffer next to the QString itself; this function should only

    // be called internally, for devices.

    Q_ASSERT(!string);

    Q_ASSERT(device);

    // handle text translation and bypass the Text flag in the device.

    bool textModeEnabled = device->isTextModeEnabled();