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//#define QIODEVICE_DEBUG

#include "qbytearray.h"

#include "qdebug.h"

#include "qiodevice_p.h"

#include "qfile.h"

#include "qstringlist.h"

#include <limits.h>

#ifdef QIODEVICE_DEBUG

#  include <ctype.h>

#endif

QT_BEGIN_NAMESPACE

#ifdef QIODEVICE_DEBUG

void debugBinaryString(const QByteArray &input)

{

    QByteArray tmp;

    int startOffset = 0;

    for (int i = 0; i < input.size(); ++i) {

        tmp += input[i];

        if ((i % 16) == 15 || i == (input.size() - 1)) {

            printf("\n%15d:", startOffset);

            startOffset += tmp.size();

            for (int j = 0; j < tmp.size(); ++j)

                printf(" %02x", int(uchar(tmp[j])));

            for (int j = tmp.size(); j < 16 + 1; ++j)

                printf("   ");

            for (int j = 0; j < tmp.size(); ++j)

                printf("%c", isprint(int(uchar(tmp[j]))) ? tmp[j] : '.');

            tmp.clear();

        }

    }

    printf("\n\n");

}

void debugBinaryString(const char *data, qint64 maxlen)

{

    debugBinaryString(QByteArray(data, maxlen));

}

#endif

#define Q_VOID

#define CHECK_MAXLEN(function, returnType) \

    do { \

        if (maxSize < 0) { \

            qWarning("QIODevice::"#function": Called with maxSize < 0"); \

            return returnType; \

        } \

    } while (0)

#define CHECK_WRITABLE(function, returnType) \

   do { \

       if ((d->openMode & WriteOnly) == 0) { \

           if (d->openMode == NotOpen) \

               return returnType; \

           qWarning("QIODevice::"#function": ReadOnly device"); \

           return returnType; \

       } \

   } while (0)

#define CHECK_READABLE(function, returnType) \

   do { \

       if ((d->openMode & ReadOnly) == 0) { \

           if (d->openMode == NotOpen) \

               return returnType; \

           qWarning("QIODevice::"#function": WriteOnly device"); \

           return returnType; \

       } \

   } while (0)

/*! \internal

 */

QIODevicePrivate::QIODevicePrivate()

    : openMode(QIODevice::NotOpen), buffer(QIODEVICE_BUFFERSIZE),

      pos(0), devicePos(0)

       , pPos(&pos), pDevicePos(&devicePos)

       , baseReadLineDataCalled(false)

       , firstRead(true)

       , accessMode(Unset)

#ifdef QT_NO_QOBJECT

       , q_ptr(0)

#endif

{

}

/*! \internal

 */

QIODevicePrivate::~QIODevicePrivate()

{

}

/*!

    \class QIODevice

    \reentrant

    \brief The QIODevice class is the base interface class of all I/O

    devices in Qt.

    \ingroup io

    QIODevice provides both a common implementation and an abstract

    interface for devices that support reading and writing of blocks

    of data, such as QFile, QBuffer and QTcpSocket. QIODevice is

    abstract and can not be instantiated, but it is common to use the

    interface it defines to provide device-independent I/O features.

    For example, Qt's XML classes operate on a QIODevice pointer,

    allowing them to be used with various devices (such as files and

    buffers).

    Before accessing the device, open() must be called to set the

    correct OpenMode (such as ReadOnly or ReadWrite). You can then

    write to the device with write() or putChar(), and read by calling

    either read(), readLine(), or readAll(). Call close() when you are

    done with the device.

    QIODevice distinguishes between two types of devices:

    random-access devices and sequential devices.

    \list

    \o Random-access devices support seeking to arbitrary

    positions using seek(). The current position in the file is

    available by calling pos(). QFile and QBuffer are examples of

    random-access devices.

    \o Sequential devices don't support seeking to arbitrary

    positions. The data must be read in one pass. The functions

    pos() and size() don't work for sequential devices.

    QTcpSocket and QProcess are examples of sequential devices.

    \endlist

    You can use isSequential() to determine the type of device.

    QIODevice emits readyRead() when new data is available for

    reading; for example, if new data has arrived on the network or if

    additional data is appended to a file that you are reading

    from. You can call bytesAvailable() to determine the number of

    bytes that are currently available for reading. It's common to use

    bytesAvailable() together with the readyRead() signal when

    programming with asynchronous devices such as QTcpSocket, where

    fragments of data can arrive at arbitrary points in

    time. QIODevice emits the bytesWritten() signal every time a

    payload of data has been written to the device. Use bytesToWrite()

    to determine the current amount of data waiting to be written.

    Certain subclasses of QIODevice, such as QTcpSocket and QProcess,

    are asynchronous. This means that I/O functions such as write()

    or read() always return immediately, while communication with the

    device itself may happen when control goes back to the event loop.

    QIODevice provides functions that allow you to force these

    operations to be performed immediately, while blocking the

    calling thread and without entering the event loop. This allows

    QIODevice subclasses to be used without an event loop, or in

    a separate thread:

    \list

    \o waitForReadyRead() - This function suspends operation in the

    calling thread until new data is available for reading.

    \o waitForBytesWritten() - This function suspends operation in the

    calling thread until one payload of data has been written to the

    device.

    \o waitFor....() - Subclasses of QIODevice implement blocking

    functions for device-specific operations. For example, QProcess

    has a function called waitForStarted() which suspends operation in

    the calling thread until the process has started.

    \endlist

    Calling these functions from the main, GUI thread, may cause your

    user interface to freeze. Example:

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

    By subclassing QIODevice, you can provide the same interface to

    your own I/O devices. Subclasses of QIODevice are only required to

    implement the protected readData() and writeData() functions.

    QIODevice uses these functions to implement all its convenience

    functions, such as getChar(), readLine() and write(). QIODevice

    also handles access control for you, so you can safely assume that

    the device is opened in write mode if writeData() is called.

    Some subclasses, such as QFile and QTcpSocket, are implemented

    using a memory buffer for intermediate storing of data. This

    reduces the number of required device accessing calls, which are

    often very slow. Buffering makes functions like getChar() and

    putChar() fast, as they can operate on the memory buffer instead

    of directly on the device itself. Certain I/O operations, however,

    don't work well with a buffer. For example, if several users open

    the same device and read it character by character, they may end

    up reading the same data when they meant to read a separate chunk

    each. For this reason, QIODevice allows you to bypass any

    buffering by passing the Unbuffered flag to open(). When

    subclassing QIODevice, remember to bypass any buffer you may use

    when the device is open in Unbuffered mode.

    \sa QBuffer QFile QTcpSocket

*/

/*!

    \typedef QIODevice::Offset

    \compat

    Use \c qint64 instead.

*/

/*!

    \typedef QIODevice::Status

    \compat

    Use QIODevice::OpenMode instead, or see the documentation for

    specific devices.

*/

/*!

    \enum QIODevice::OpenModeFlag

    This enum is used with open() to describe the mode in which a device

    is opened. It is also returned by openMode().

    \value NotOpen   The device is not open.

    \value ReadOnly  The device is open for reading.

    \value WriteOnly The device is open for writing.

    \value ReadWrite The device is open for reading and writing.

    \value Append    The device is opened in append mode, so that all data is

                     written to the end of the file.

    \value Truncate  If possible, the device is truncated before it is opened.

                     All earlier contents of the device are lost.

    \value Text      When reading, the end-of-line terminators are

                     translated to '\n'. When writing, the end-of-line

                     terminators are translated to the local encoding, for

                     example '\r\n' for Win32.

    \value Unbuffered Any buffer in the device is bypassed.

    Certain flags, such as \c Unbuffered and \c Truncate, are

    meaningless when used with some subclasses. Some of these

    restrictions are implied by the type of device that is represented

    by a subclass. In other cases, the restriction may be due to the

    implementation, or may be imposed by the underlying platform; for

    example, QTcpSocket does not support \c Unbuffered mode, and

    limitations in the native API prevent QFile from supporting \c

    Unbuffered on Windows.

*/

/*!     \fn QIODevice::bytesWritten(qint64 bytes)

    This signal is emitted every time a payload of data has been

    written to the device. The \a bytes argument is set to the number

    of bytes that were written in this payload.

    bytesWritten() is not emitted recursively; if you reenter the event loop

    or call waitForBytesWritten() inside a slot connected to the

    bytesWritten() signal, the signal will not be reemitted (although

    waitForBytesWritten() may still return true).

    \sa readyRead()

*/

/*!

    \fn QIODevice::readyRead()

    This signal is emitted once every time new data is available for

    reading from the device. It will only be emitted again once new

    data is available, such as when a new payload of network data has

    arrived on your network socket, or when a new block of data has

    been appended to your device.

    readyRead() is not emitted recursively; if you reenter the event loop or

    call waitForReadyRead() inside a slot connected to the readyRead() signal,

    the signal will not be reemitted (although waitForReadyRead() may still

    return true).

    Note for developers implementing classes derived from QIODevice:

    you should always emit readyRead() when new data has arrived (do not

    emit it only because there's data still to be read in your

    buffers). Do not emit readyRead() in other conditions.

    \sa bytesWritten()

*/

/*! \fn QIODevice::aboutToClose()

    This signal is emitted when the device is about to close. Connect

    this signal if you have operations that need to be performed

    before the device closes (e.g., if you have data in a separate

    buffer that needs to be written to the device).

*/

/*!

    \fn QIODevice::readChannelFinished()

    \since 4.4

    This signal is emitted when the input (reading) stream is closed

    in this device. It is emitted as soon as the closing is detected,

    which means that there might still be data available for reading

    with read().

    \sa atEnd(), read()

*/

#ifdef QT_NO_QOBJECT

QIODevice::QIODevice()

    : d_ptr(new QIODevicePrivate)

{

    d_ptr->q_ptr = this;

}

/*! \internal

*/

QIODevice::QIODevice(QIODevicePrivate &dd)

    : d_ptr(&dd)

{

    d_ptr->q_ptr = this;

}

#else

/*!

    Constructs a QIODevice object.

*/

QIODevice::QIODevice()

    : QObject(*new QIODevicePrivate, 0)

{

#if defined QIODEVICE_DEBUG

    QFile *file = qobject_cast<QFile *>(this);

    printf("%p QIODevice::QIODevice(\"%s\") %s\n", this, metaObject()->className(),

           qPrintable(file ? file->fileName() : QString()));

#endif

}

/*!

    Constructs a QIODevice object with the given \a parent.

*/

QIODevice::QIODevice(QObject *parent)

    : QObject(*new QIODevicePrivate, parent)

{

#if defined QIODEVICE_DEBUG

    printf("%p QIODevice::QIODevice(%p \"%s\")\n", this, parent, metaObject()->className());

#endif

}

/*! \internal

*/

QIODevice::QIODevice(QIODevicePrivate &dd, QObject *parent)

    : QObject(dd, parent)

{

}

#endif

/*!

    Destructs the QIODevice object.

*/

QIODevice::~QIODevice()

{

#if defined QIODEVICE_DEBUG

    printf("%p QIODevice::~QIODevice()\n", this);

#endif

}

/*!

    Returns true if this device is sequential; otherwise returns

    false.

    Sequential devices, as opposed to a random-access devices, have no

    concept of a start, an end, a size, or a current position, and they

    do not support seeking. You can only read from the device when it

    reports that data is available. The most common example of a

    sequential device is a network socket. On Unix, special files such

    as /dev/zero and fifo pipes are sequential.

    Regular files, on the other hand, do support random access. They

    have both a size and a current position, and they also support

    seeking backwards and forwards in the data stream. Regular files

    are non-sequential.

    \sa bytesAvailable()

*/

bool QIODevice::isSequential() const

{

    return false;

}

/*!

    Returns the mode in which the device has been opened;

    i.e. ReadOnly or WriteOnly.

    \sa OpenMode

*/

QIODevice::OpenMode QIODevice::openMode() const

{

    return d_func()->openMode;

}

/*!

    Sets the OpenMode of the device to \a openMode. Call this

    function to set the open mode if the flags change after the device

    has been opened.

    \sa openMode() OpenMode

*/

void QIODevice::setOpenMode(OpenMode openMode)

{

    Q_D(QIODevice);

#if defined QIODEVICE_DEBUG

    printf("%p QIODevice::setOpenMode(0x%x)\n", this, int(openMode));

#endif

    d->openMode = openMode;

    d->accessMode = QIODevicePrivate::Unset;

    d->firstRead = true;

    if (!isReadable())

        d->buffer.clear();

}

/*!

    If \a enabled is true, this function sets the \l Text flag on the device;

    otherwise the \l Text flag is removed. This feature is useful for classes

    that provide custom end-of-line handling on a QIODevice.

    \sa open(), setOpenMode()

 */

void QIODevice::setTextModeEnabled(bool enabled)

{

    Q_D(QIODevice);

    if (enabled)

        d->openMode |= Text;

    else

        d->openMode &= ~Text;

}

/*!

    Returns true if the \l Text flag is enabled; otherwise returns false.

    \sa setTextModeEnabled()

*/

bool QIODevice::isTextModeEnabled() const

{

    return d_func()->openMode & Text;

}

/*!

    Returns true if the device is open; otherwise returns false. A

    device is open if it can be read from and/or written to. By

    default, this function returns false if openMode() returns

    \c NotOpen.

    \sa openMode() OpenMode

*/

bool QIODevice::isOpen() const

{

    return d_func()->openMode != NotOpen;

}

/*!

    Returns true if data can be read from the device; otherwise returns

    false. Use bytesAvailable() to determine how many bytes can be read.

    This is a convenience function which checks if the OpenMode of the

    device contains the ReadOnly flag.

    \sa openMode() OpenMode

*/

bool QIODevice::isReadable() const

{

    return (openMode() & ReadOnly) != 0;

}

/*!

    Returns true if data can be written to the device; otherwise returns

    false.

    This is a convenience function which checks if the OpenMode of the

    device contains the WriteOnly flag.

    \sa openMode() OpenMode

*/

bool QIODevice::isWritable() const

{

    return (openMode() & WriteOnly) != 0;

}