source: trunk/src/plugins/gfxdrivers/vnc/qscreenvnc_qws.cpp@ 846

/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation ([email protected])
**
** This file is part of the plugins of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial Usage
** Licensees holding valid Qt Commercial licenses may use this file in
** accordance with the Qt Commercial License Agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Nokia.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** 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
** met: http://www.gnu.org/copyleft/gpl.html.
**
** If you have questions regarding the use of this file, please contact
** Nokia at [email protected].
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qscreenvnc_qws.h"

#ifndef QT_NO_QWS_VNC

#include "qscreenvnc_p.h"
#include "qwindowsystem_qws.h"
#include "qwsdisplay_qws.h"
#include "qscreendriverfactory_qws.h"
#include <QtCore/qtimer.h>
#include <QtCore/qregexp.h>
#include <QtGui/qwidget.h>
#include <QtGui/qpolygon.h>
#include <QtGui/qpainter.h>
#include <qdebug.h>
#include <private/qwindowsurface_qws_p.h>
#include <private/qwssignalhandler_p.h>
#include <private/qwidget_p.h>
#include <private/qdrawhelper_p.h>

#include <stdlib.h>

QT_BEGIN_NAMESPACE

//#define QT_QWS_VNC_DEBUG

extern QString qws_qtePipeFilename();

#ifndef QT_NO_QWS_CURSOR

QVNCCursor::QVNCCursor(QVNCScreen *s)
    : screen(s)
{
    if (qt_screencursor)
        setScreenCursor(qt_screencursor);
    else
        hwaccel = true;
}

QVNCCursor::~QVNCCursor()
{
    if (screenCursor())
        qt_screencursor = screenCursor();
}

void QVNCCursor::setDirty(const QRect &r) const
{
    screen->d_ptr->setDirty(r, true);
}

void QVNCCursor::hide()
{
    QProxyScreenCursor::hide();
    if (enable)
        setDirty(boundingRect());
}

void QVNCCursor::show()
{
    QProxyScreenCursor::show();
    if (enable)
        setDirty(boundingRect());
}

void QVNCCursor::set(const QImage &image, int hotx, int hoty)
{
    QRegion dirty = boundingRect();
    QProxyScreenCursor::set(image, hotx, hoty);
    dirty |= boundingRect();
    if (enable && hwaccel && !screen->d_ptr->vncServer->hasClientCursor()) {
        const QVector<QRect> rects = dirty.rects();
        for (int i = 0; i < rects.size(); ++i)
            setDirty(rects.at(i));
    }
}

void QVNCCursor::move(int x, int y)
{
    if (enable && hwaccel && !screen->d_ptr->vncServer->hasClientCursor()) {
        QRegion dirty = boundingRect();
        QProxyScreenCursor::move(x, y);
        dirty |= boundingRect();
        if (enable) {
            const QVector<QRect> rects = dirty.rects();
            for (int i = 0; i < rects.size(); ++i)
                setDirty(rects.at(i));
        }
    } else {
        QProxyScreenCursor::move(x, y);
    }
}

QVNCClientCursor::QVNCClientCursor(QVNCServer *s)
    : server(s)
{
    setScreenCursor(qt_screencursor);
    Q_ASSERT(hwaccel);
    qt_screencursor = this; // hw: XXX

    set(image(), hotspot.x(), hotspot.y());
}

QVNCClientCursor::~QVNCClientCursor()
{
    qt_screencursor = screenCursor();
}

void QVNCClientCursor::set(const QImage &image, int hotx, int hoty)
{
    QScreenCursor::set(image, hotx, hoty);
    server->setDirtyCursor();
}

void QVNCClientCursor::write() const
{
    QTcpSocket *socket = server->clientSocket();

    // FramebufferUpdate header
    {
        const quint16 tmp[6] = { htons(0),
                                 htons(1),
                                 htons(hotspot.x()), htons(hotspot.y()),
                                 htons(cursor.width()),
                                 htons(cursor.height()) };
        socket->write((char*)tmp, sizeof(tmp));

        const quint32 encoding = htonl(-239);
        socket->write((char*)(&encoding), sizeof(encoding));
    }

    if (cursor.isNull())
        return;

    // write pixels
    Q_ASSERT(cursor.hasAlphaChannel());
    const QImage img = cursor.convertToFormat(server->screen()->pixelFormat());
    const int n = server->clientBytesPerPixel() * img.width();
    char *buffer = new char[n];
    for (int i = 0; i < img.height(); ++i) {
        server->convertPixels(buffer, (const char*)img.scanLine(i), img.width());
        socket->write(buffer, n);
    }
    delete[] buffer;

    // write mask
    const QImage bitmap = cursor.createAlphaMask().convertToFormat(QImage::Format_Mono);
    Q_ASSERT(bitmap.depth() == 1);
    Q_ASSERT(bitmap.size() == img.size());
    const int width = (bitmap.width() + 7) / 8;
    for (int i = 0; i < bitmap.height(); ++i)
        socket->write((const char*)bitmap.scanLine(i), width);
}

#endif // QT_NO_QWS_CURSOR

QVNCScreenPrivate::QVNCScreenPrivate(QVNCScreen *parent)
    : dpiX(72), dpiY(72), doOnScreenSurface(false), refreshRate(25),
      vncServer(0), q_ptr(parent), noDisablePainting(false)
{
#ifdef QT_BUILD_INTERNAL
    noDisablePainting = (qgetenv("QT_VNC_NO_DISABLEPAINTING").toInt() > 0);
#endif
#ifndef QT_NO_QWS_SIGNALHANDLER
    QWSSignalHandler::instance()->addObject(this);
#endif
}

QVNCScreenPrivate::~QVNCScreenPrivate()
{
#if defined(QT_NO_QWS_MULTIPROCESS) || defined(QT_NO_SHAREDMEMORY)
    if (q_ptr->screen())
        return;

    delete[] q_ptr->data;
    q_ptr->data = 0;
#else
    shm.detach();
#endif
}

void QVNCScreenPrivate::configure()
{
    if (q_ptr->screen())
        return;

    q_ptr->lstep = q_ptr->dw * ((q_ptr->d + 7) / 8);
    q_ptr->size = q_ptr->h * q_ptr->lstep;
    q_ptr->mapsize = q_ptr->size;
    q_ptr->physWidth = qRound(q_ptr->dw * qreal(25.4) / dpiX);
    q_ptr->physHeight = qRound(q_ptr->dh * qreal(25.4) / dpiY);

    switch (q_ptr->d) {
    case 1:
        q_ptr->setPixelFormat(QImage::Format_Mono); //### LSB???
        break;
    case 8:
        q_ptr->setPixelFormat(QImage::Format_Indexed8);
        break;
    case 12:
        q_ptr->setPixelFormat(QImage::Format_RGB444);
        break;
    case 15:
        q_ptr->setPixelFormat(QImage::Format_RGB555);
        break;
    case 16:
        q_ptr->setPixelFormat(QImage::Format_RGB16);
        break;
    case 18:
        q_ptr->setPixelFormat(QImage::Format_RGB666);
        break;
    case 24:
        q_ptr->setPixelFormat(QImage::Format_RGB888);
        break;
    case 32:
        q_ptr->setPixelFormat(QImage::Format_ARGB32_Premultiplied);
        break;
    }

#if !defined(QT_NO_QWS_MULTIPROCESS) && !defined(QT_NO_SHAREDMEMORY)
    if (q_ptr->size != shm.size()) {
        shm.detach();
        const QString key = qws_qtePipeFilename() +
                            QString().sprintf("_vnc_%d_%d",
                                              q_ptr->displayId, q_ptr->size);
        shm.setKey(key);
        if (QApplication::type() == QApplication::GuiServer) {
            if (!shm.create(q_ptr->size)) {
                qWarning() << "QVNCScreen could not create shared memory:"
                           << shm.errorString();
                if (!shm.attach()) {
                    qWarning() << "QVNCScreen could not attach to shared memory:"
                               << shm.errorString();
                }
            }
        } else if (!shm.attach()) {
            qWarning() << "QVNCScreen could not attach to shared memory:"
                       << shm.errorString();
        }
        q_ptr->data = reinterpret_cast<uchar*>(shm.data());
    }
#else
    if (q_ptr->data)
        delete[] q_ptr->data;
    q_ptr->data = new uchar[q_ptr->size];
#endif
}

//===========================================================================

static const struct {
    int keysym;
    int keycode;
} keyMap[] = {
    { 0xff08, Qt::Key_Backspace },
    { 0xff09, Qt::Key_Tab       },
    { 0xff0d, Qt::Key_Return    },
    { 0xff1b, Qt::Key_Escape    },
    { 0xff63, Qt::Key_Insert    },
    { 0xffff, Qt::Key_Delete    },
    { 0xff50, Qt::Key_Home      },
    { 0xff57, Qt::Key_End       },
    { 0xff55, Qt::Key_PageUp    },
    { 0xff56, Qt::Key_PageDown  },
    { 0xff51, Qt::Key_Left      },
    { 0xff52, Qt::Key_Up        },
    { 0xff53, Qt::Key_Right     },
    { 0xff54, Qt::Key_Down      },
    { 0xffbe, Qt::Key_F1        },
    { 0xffbf, Qt::Key_F2        },
    { 0xffc0, Qt::Key_F3        },
    { 0xffc1, Qt::Key_F4        },
    { 0xffc2, Qt::Key_F5        },
    { 0xffc3, Qt::Key_F6        },
    { 0xffc4, Qt::Key_F7        },
    { 0xffc5, Qt::Key_F8        },
    { 0xffc6, Qt::Key_F9        },
    { 0xffc7, Qt::Key_F10       },
    { 0xffc8, Qt::Key_F11       },
    { 0xffc9, Qt::Key_F12       },
    { 0xffe1, Qt::Key_Shift     },
    { 0xffe2, Qt::Key_Shift     },
    { 0xffe3, Qt::Key_Control   },
    { 0xffe4, Qt::Key_Control   },
    { 0xffe7, Qt::Key_Meta      },
    { 0xffe8, Qt::Key_Meta      },
    { 0xffe9, Qt::Key_Alt       },
    { 0xffea, Qt::Key_Alt       },

    { 0xffb0, Qt::Key_0         },
    { 0xffb1, Qt::Key_1         },
    { 0xffb2, Qt::Key_2         },
    { 0xffb3, Qt::Key_3         },
    { 0xffb4, Qt::Key_4         },
    { 0xffb5, Qt::Key_5         },
    { 0xffb6, Qt::Key_6         },
    { 0xffb7, Qt::Key_7         },
    { 0xffb8, Qt::Key_8         },
    { 0xffb9, Qt::Key_9         },

    { 0xff8d, Qt::Key_Return    },
    { 0xffaa, Qt::Key_Asterisk  },
    { 0xffab, Qt::Key_Plus      },
    { 0xffad, Qt::Key_Minus     },
    { 0xffae, Qt::Key_Period    },
    { 0xffaf, Qt::Key_Slash     },

    { 0xff95, Qt::Key_Home      },
    { 0xff96, Qt::Key_Left      },
    { 0xff97, Qt::Key_Up        },
    { 0xff98, Qt::Key_Right     },
    { 0xff99, Qt::Key_Down      },
    { 0xff9a, Qt::Key_PageUp    },
    { 0xff9b, Qt::Key_PageDown  },
    { 0xff9c, Qt::Key_End       },
    { 0xff9e, Qt::Key_Insert    },
    { 0xff9f, Qt::Key_Delete    },

    { 0, 0 }
};

void QRfbRect::read(QTcpSocket *s)
{
    quint16 buf[4];
    s->read((char*)buf, 8);
    x = ntohs(buf[0]);
    y = ntohs(buf[1]);
    w = ntohs(buf[2]);
    h = ntohs(buf[3]);
}

void QRfbRect::write(QTcpSocket *s) const
{
    quint16 buf[4];
    buf[0] = htons(x);
    buf[1] = htons(y);
    buf[2] = htons(w);
    buf[3] = htons(h);
    s->write((char*)buf, 8);
}

void QRfbPixelFormat::read(QTcpSocket *s)
{
    char buf[16];
    s->read(buf, 16);
    bitsPerPixel = buf[0];
    depth = buf[1];
    bigEndian = buf[2];
    trueColor = buf[3];

    quint16 a = ntohs(*(quint16 *)(buf + 4));
    redBits = 0;
    while (a) { a >>= 1; redBits++; }

    a = ntohs(*(quint16 *)(buf + 6));
    greenBits = 0;
    while (a) { a >>= 1; greenBits++; }

    a = ntohs(*(quint16 *)(buf + 8));
    blueBits = 0;
    while (a) { a >>= 1; blueBits++; }

    redShift = buf[10];
    greenShift = buf[11];
    blueShift = buf[12];
}

void QRfbPixelFormat::write(QTcpSocket *s)
{
    char buf[16];
    buf[0] = bitsPerPixel;
    buf[1] = depth;
    buf[2] = bigEndian;
    buf[3] = trueColor;

    quint16 a = 0;
    for (int i = 0; i < redBits; i++) a = (a << 1) | 1;
    *(quint16 *)(buf + 4) = htons(a);

    a = 0;
    for (int i = 0; i < greenBits; i++) a = (a << 1) | 1;
    *(quint16 *)(buf + 6) = htons(a);

    a = 0;
    for (int i = 0; i < blueBits; i++) a = (a << 1) | 1;
    *(quint16 *)(buf + 8) = htons(a);

    buf[10] = redShift;
    buf[11] = greenShift;
    buf[12] = blueShift;
    s->write(buf, 16);
}


void QRfbServerInit::setName(const char *n)
{
    delete[] name;
    name = new char [strlen(n) + 1];
    strcpy(name, n);
}

void QRfbServerInit::read(QTcpSocket *s)
{
    s->read((char *)&width, 2);
    width = ntohs(width);
    s->read((char *)&height, 2);
    height = ntohs(height);
    format.read(s);

    quint32 len;
    s->read((char *)&len, 4);
    len = ntohl(len);

    name = new char [len + 1];
    s->read(name, len);
    name[len] = '\0';
}

void QRfbServerInit::write(QTcpSocket *s)
{
    quint16 t = htons(width);
    s->write((char *)&t, 2);
    t = htons(height);
    s->write((char *)&t, 2);
    format.write(s);
    quint32 len = strlen(name);
    len = htonl(len);
    s->write((char *)&len, 4);
    s->write(name, strlen(name));
}

bool QRfbSetEncodings::read(QTcpSocket *s)
{
    if (s->bytesAvailable() < 3)
        return false;

    char tmp;
    s->read(&tmp, 1);        // padding
    s->read((char *)&count, 2);
    count = ntohs(count);

    return true;
}

bool QRfbFrameBufferUpdateRequest::read(QTcpSocket *s)
{
    if (s->bytesAvailable() < 9)
        return false;

    s->read(&incremental, 1);
    rect.read(s);

    return true;
}

bool QRfbKeyEvent::read(QTcpSocket *s)
{
    if (s->bytesAvailable() < 7)
        return false;

    s->read(&down, 1);
    quint16 tmp;
    s->read((char *)&tmp, 2);  // padding

    quint32 key;
    s->read((char *)&key, 4);
    key = ntohl(key);

    unicode = 0;
    keycode = 0;
    int i = 0;
    while (keyMap[i].keysym && !keycode) {
        if (keyMap[i].keysym == (int)key)
            keycode = keyMap[i].keycode;
        i++;
    }

    if (keycode >= ' ' && keycode <= '~')
        unicode = keycode;

    if (!keycode) {
        if (key <= 0xff) {
            unicode = key;
            if (key >= 'a' && key <= 'z')
                keycode = Qt::Key_A + key - 'a';
            else if (key >= ' ' && key <= '~')
                keycode = Qt::Key_Space + key - ' ';
        }
    }

    return true;
}

bool QRfbPointerEvent::read(QTcpSocket *s)
{
    if (s->bytesAvailable() < 5)
        return false;

    char buttonMask;
    s->read(&buttonMask, 1);
    buttons = 0;
    if (buttonMask & 1)
        buttons |= Qt::LeftButton;
    if (buttonMask & 2)
        buttons |= Qt::MidButton;
    if (buttonMask & 4)
        buttons |= Qt::RightButton;

    quint16 tmp;
    s->read((char *)&tmp, 2);
    x = ntohs(tmp);
    s->read((char *)&tmp, 2);
    y = ntohs(tmp);

    return true;
}

bool QRfbClientCutText::read(QTcpSocket *s)
{
    if (s->bytesAvailable() < 7)
        return false;

    char tmp[3];
    s->read(tmp, 3);        // padding
    s->read((char *)&length, 4);
    length = ntohl(length);

    return true;
}

//===========================================================================

QVNCServer::QVNCServer(QVNCScreen *screen)
    : qvnc_screen(screen)
{
    init(5900);
}

QVNCServer::QVNCServer(QVNCScreen *screen, int id)
    : qvnc_screen(screen)
{
    init(5900 + id);
}

void QVNCServer::init(uint port)
{
    handleMsg = false;
    client = 0;
    encodingsPending = 0;
    cutTextPending = 0;
    keymod = 0;
    state = Unconnected;
    dirtyCursor = false;

    refreshRate = 25;
    timer = new QTimer(this);
    timer->setSingleShot(true);
    connect(timer, SIGNAL(timeout()), this, SLOT(checkUpdate()));

    serverSocket = new QTcpServer(this);
    if (!serverSocket->listen(QHostAddress::Any, port))
        qDebug() << "QVNCServer could not connect:" << serverSocket->errorString();
    else
        qDebug("QVNCServer created on port %d", port);

    connect(serverSocket, SIGNAL(newConnection()), this, SLOT(newConnection()));

#ifndef QT_NO_QWS_CURSOR
    qvnc_cursor = 0;
#endif
    encoder = 0;
}

QVNCServer::~QVNCServer()
{
    delete encoder;
    encoder = 0;
    delete client;
    client = 0;
#ifndef QT_NO_QWS_CURSOR
    delete qvnc_cursor;
    qvnc_cursor = 0;
#endif
}

void QVNCServer::setDirty()
{
    if (state == Connected && !timer->isActive() &&
        ((dirtyMap()->numDirty > 0) || dirtyCursor)) {
        timer->start();
    }
}

void QVNCServer::newConnection()
{
    if (client)
        delete client;

    client = serverSocket->nextPendingConnection();
    connect(client,SIGNAL(readyRead()),this,SLOT(readClient()));
    connect(client,SIGNAL(disconnected()),this,SLOT(discardClient()));
    handleMsg = false;
    encodingsPending = 0;
    cutTextPending = 0;
    supportHextile = false;
    wantUpdate = false;

    timer->start(1000 / refreshRate);
    dirtyMap()->reset();

    // send protocol version
    const char *proto = "RFB 003.003\n";
    client->write(proto, 12);
    state = Protocol;

    if (!qvnc_screen->screen() && !qvnc_screen->d_ptr->noDisablePainting)
        QWSServer::instance()->enablePainting(true);
}

void QVNCServer::readClient()
{
    switch (state) {
        case Protocol:
            if (client->bytesAvailable() >= 12) {
                char proto[13];
                client->read(proto, 12);
                proto[12] = '\0';
                qDebug("Client protocol version %s", proto);
                // No authentication
                quint32 auth = htonl(1);
                client->write((char *) &auth, sizeof(auth));
                state = Init;
            }
            break;

        case Init:
            if (client->bytesAvailable() >= 1) {
                quint8 shared;
                client->read((char *) &shared, 1);

                // Server Init msg
                QRfbServerInit sim;
                QRfbPixelFormat &format = sim.format;
                switch (qvnc_screen->depth()) {
                case 32:
                    format.bitsPerPixel = 32;
                    format.depth = 32;
                    format.bigEndian = 0;
                    format.trueColor = true;
                    format.redBits = 8;
                    format.greenBits = 8;
                    format.blueBits = 8;
                    format.redShift = 16;
                    format.greenShift = 8;
                    format.blueShift = 0;
                    break;

                case 24:
                    format.bitsPerPixel = 24;
                    format.depth = 24;
                    format.bigEndian = 0;
                    format.trueColor = true;
                    format.redBits = 8;
                    format.greenBits = 8;
                    format.blueBits = 8;
                    format.redShift = 16;
                    format.greenShift = 8;
                    format.blueShift = 0;
                    break;

                case 18:
                    format.bitsPerPixel = 24;
                    format.depth = 18;
                    format.bigEndian = 0;
                    format.trueColor = true;
                    format.redBits = 6;
                    format.greenBits = 6;
                    format.blueBits = 6;
                    format.redShift = 12;
                    format.greenShift = 6;
                    format.blueShift = 0;
                    break;

                case 16:
                    format.bitsPerPixel = 16;
                    format.depth = 16;
                    format.bigEndian = 0;
                    format.trueColor = true;
                    format.redBits = 5;
                    format.greenBits = 6;
                    format.blueBits = 5;
                    format.redShift = 11;
                    format.greenShift = 5;
                    format.blueShift = 0;
                    break;

                case 15:
                    format.bitsPerPixel = 16;
                    format.depth = 15;
                    format.bigEndian = 0;
                    format.trueColor = true;
                    format.redBits = 5;
                    format.greenBits = 5;
                    format.blueBits = 5;
                    format.redShift = 10;
                    format.greenShift = 5;
                    format.blueShift = 0;
                    break;

                case 12:
                    format.bitsPerPixel = 16;
                    format.depth = 12;
                    format.bigEndian = 0;
                    format.trueColor = true;
                    format.redBits = 4;
                    format.greenBits = 4;
                    format.blueBits = 4;
                    format.redShift = 8;
                    format.greenShift = 4;
                    format.blueShift = 0;
                    break;

                case 8:
                case 4:
                    format.bitsPerPixel = 8;
                    format.depth = 8;
                    format.bigEndian = 0;
                    format.trueColor = false;
                    format.redBits = 0;
                    format.greenBits = 0;
                    format.blueBits = 0;
                    format.redShift = 0;
                    format.greenShift = 0;
                    format.blueShift = 0;
                    break;

                default:
                    qDebug("QVNC cannot drive depth %d", qvnc_screen->depth());
                    discardClient();
                    return;
                }
                sim.width = qvnc_screen->deviceWidth();
                sim.height = qvnc_screen->deviceHeight();
                sim.setName("Qt for Embedded Linux VNC Server");
                sim.write(client);
                state = Connected;
            }
            break;

        case Connected:
            do {
                if (!handleMsg) {
                    client->read((char *)&msgType, 1);
                    handleMsg = true;
                }
                if (handleMsg) {
                    switch (msgType ) {
                    case SetPixelFormat:
                        setPixelFormat();
                        break;
                    case FixColourMapEntries:
                        qDebug("Not supported: FixColourMapEntries");
                        handleMsg = false;
                        break;
                    case SetEncodings:
                        setEncodings();
                        break;
                    case FramebufferUpdateRequest:
                        frameBufferUpdateRequest();
                        break;
                    case KeyEvent:
                        keyEvent();
                        break;
                    case PointerEvent:
                        pointerEvent();
                        break;
                    case ClientCutText:
                        clientCutText();
                        break;
                    default:
                        qDebug("Unknown message type: %d", (int)msgType);
                        handleMsg = false;
                    }
                }
            } while (!handleMsg && client->bytesAvailable());
            break;
    default:
        break;
    }
}

#if Q_BYTE_ORDER == Q_BIG_ENDIAN
bool QVNCScreen::swapBytes() const
{
    if (depth() != 16)
        return false;

    if (screen())
        return screen()->frameBufferLittleEndian();
    return frameBufferLittleEndian();
}
#endif

void QVNCServer::setPixelFormat()
{
    if (client->bytesAvailable() >= 19) {
        char buf[3];
        client->read(buf, 3); // just padding
        pixelFormat.read(client);
#ifdef QT_QWS_VNC_DEBUG
        qDebug("Want format: %d %d %d %d %d %d %d %d %d %d",
            int(pixelFormat.bitsPerPixel),
            int(pixelFormat.depth),
            int(pixelFormat.bigEndian),
            int(pixelFormat.trueColor),
            int(pixelFormat.redBits),
            int(pixelFormat.greenBits),
            int(pixelFormat.blueBits),
            int(pixelFormat.redShift),
            int(pixelFormat.greenShift),
            int(pixelFormat.blueShift));
#endif
        if (!pixelFormat.trueColor) {
            qDebug("Can only handle true color clients");
            discardClient();
        }
        handleMsg = false;
        sameEndian = (QSysInfo::ByteOrder == QSysInfo::BigEndian) == !!pixelFormat.bigEndian;
        needConversion = pixelConversionNeeded();
#if Q_BYTE_ORDER == Q_BIG_ENDIAN
        swapBytes = qvnc_screen->swapBytes();
#endif
    }
}

void QVNCServer::setEncodings()
{
    QRfbSetEncodings enc;

    if (!encodingsPending && enc.read(client)) {
        encodingsPending = enc.count;
        if (!encodingsPending)
            handleMsg = false;
    }

    if (encoder) {
        delete encoder;
        encoder = 0;
    }

    enum Encodings {
        Raw = 0,
        CopyRect = 1,
        RRE = 2,
        CoRRE = 4,
        Hextile = 5,
        ZRLE = 16,
        Cursor = -239,
        DesktopSize = -223
    };

    if (encodingsPending && (unsigned)client->bytesAvailable() >=
                                encodingsPending * sizeof(quint32)) {
        for (int i = 0; i < encodingsPending; ++i) {
            qint32 enc;
            client->read((char *)&enc, sizeof(qint32));
            enc = ntohl(enc);
#ifdef QT_QWS_VNC_DEBUG
            qDebug("QVNCServer::setEncodings: %d", enc);
#endif
            switch (enc) {
            case Raw:
                if (!encoder) {
                    encoder = new QRfbRawEncoder(this);
#ifdef QT_QWS_VNC_DEBUG
                    qDebug("QVNCServer::setEncodings: using raw");
#endif
                }
               break;
            case CopyRect:
                supportCopyRect = true;
                break;
            case RRE:
                supportRRE = true;
                break;
            case CoRRE:
                supportCoRRE = true;
                break;
            case Hextile:
                supportHextile = true;
                if (encoder)
                    break;
                switch (qvnc_screen->depth()) {
#ifdef QT_QWS_DEPTH_8
                case 8:
                    encoder = new QRfbHextileEncoder<quint8>(this);
                    break;
#endif
#ifdef QT_QWS_DEPTH_12
                case 12:
                    encoder = new QRfbHextileEncoder<qrgb444>(this);
                    break;
#endif
#ifdef QT_QWS_DEPTH_15
                case 15:
                    encoder = new QRfbHextileEncoder<qrgb555>(this);
                    break;
#endif
#ifdef QT_QWS_DEPTH_16
                case 16:
                    encoder = new QRfbHextileEncoder<quint16>(this);
                    break;
#endif
#ifdef QT_QWS_DEPTH_18
                case 18:
                    encoder = new QRfbHextileEncoder<qrgb666>(this);
                    break;
#endif
#ifdef QT_QWS_DEPTH_24
                case 24:
                    encoder = new QRfbHextileEncoder<qrgb888>(this);
                    break;
#endif
#ifdef QT_QWS_DEPTH_32
                case 32:
                    encoder = new QRfbHextileEncoder<quint32>(this);
                    break;
#endif
                default:
                    break;
                }
#ifdef QT_QWS_VNC_DEBUG
                qDebug("QVNCServer::setEncodings: using hextile");
#endif
                break;
            case ZRLE:
                supportZRLE = true;
                break;
            case Cursor:
                supportCursor = true;
#ifndef QT_NO_QWS_CURSOR
                if (!qvnc_screen->screen() || qt_screencursor->isAccelerated()) {
                    delete qvnc_cursor;
                    qvnc_cursor = new QVNCClientCursor(this);
                }
#endif
                break;
            case DesktopSize:
                supportDesktopSize = true;
                break;
            default:
                break;
            }
        }
        handleMsg = false;
        encodingsPending = 0;
    }

    if (!encoder) {
        encoder = new QRfbRawEncoder(this);
#ifdef QT_QWS_VNC_DEBUG
        qDebug("QVNCServer::setEncodings: fallback using raw");
#endif
    }
}

void QVNCServer::frameBufferUpdateRequest()
{
    QRfbFrameBufferUpdateRequest ev;

    if (ev.read(client)) {
        if (!ev.incremental) {
            QRect r(ev.rect.x, ev.rect.y, ev.rect.w, ev.rect.h);
            r.translate(qvnc_screen->offset());
            qvnc_screen->d_ptr->setDirty(r, true);
        }
        wantUpdate = true;
        checkUpdate();
        handleMsg = false;
    }
}

void QVNCServer::pointerEvent()
{
    QRfbPointerEvent ev;
    if (ev.read(client)) {
        const QPoint offset = qvnc_screen->offset();
        QWSServer::sendMouseEvent(offset + QPoint(ev.x, ev.y), ev.buttons);
        handleMsg = false;
    }
}

void QVNCServer::keyEvent()
{
    QRfbKeyEvent ev;

    if (ev.read(client)) {
        if (ev.keycode == Qt::Key_Shift)
            keymod = ev.down ? keymod | Qt::ShiftModifier :
                               keymod & ~Qt::ShiftModifier;
        else if (ev.keycode == Qt::Key_Control)
            keymod = ev.down ? keymod | Qt::ControlModifier :
                               keymod & ~Qt::ControlModifier;
        else if (ev.keycode == Qt::Key_Alt)
            keymod = ev.down ? keymod | Qt::AltModifier :
                               keymod & ~Qt::AltModifier;
        if (ev.unicode || ev.keycode)
            QWSServer::sendKeyEvent(ev.unicode, ev.keycode, keymod, ev.down, false);
        handleMsg = false;
    }
}

void QVNCServer::clientCutText()
{
    QRfbClientCutText ev;

    if (cutTextPending == 0 && ev.read(client)) {
        cutTextPending = ev.length;
        if (!cutTextPending)
            handleMsg = false;
    }

    if (cutTextPending && client->bytesAvailable() >= cutTextPending) {
        char *text = new char [cutTextPending+1];
        client->read(text, cutTextPending);
        delete [] text;
        cutTextPending = 0;
        handleMsg = false;
    }
}

// stride in bytes
template <class SRC>
bool QRfbSingleColorHextile<SRC>::read(const uchar *data,
                                       int width, int height, int stride)
{
    const int depth = encoder->server->screen()->depth();
    if (width % (depth / 8)) // hw: should rather fallback to simple loop
        return false;

    static int alwaysFalse = qgetenv("QT_VNC_NOCHECKFILL").toInt();
    if (alwaysFalse)
        return false;

    switch (depth) {
    case 4: {
        const quint8 *data8 = reinterpret_cast<const quint8*>(data);
        if ((data8[0] & 0xf) != (data8[0] >> 4))
            return false;
        width /= 2;
    } // fallthrough
    case 8: {
        const quint8 *data8 = reinterpret_cast<const quint8*>(data);
        if (data8[0] != data8[1])
            return false;
        width /= 2;
    } // fallthrough
    case 12:
    case 15:
    case 16: {
        const quint16 *data16 = reinterpret_cast<const quint16*>(data);
        if (data16[0] != data16[1])
            return false;
        width /= 2;
    } // fallthrough
    case 18:
    case 24:
    case 32: {
        const quint32 *data32 = reinterpret_cast<const quint32*>(data);
        const quint32 first = data32[0];
        const int linestep = (stride / sizeof(quint32)) - width;
        for (int y = 0; y < height; ++y) {
            for (int x = 0; x < width; ++x) {
                if (*(data32++) != first)
                    return false;
            }
            data32 += linestep;
        }
        break;
    }
    default:
        return false;
    }

    SRC color = reinterpret_cast<const SRC*>(data)[0];
    encoder->newBg |= (color != encoder->bg);
    encoder->bg = color;
    return true;
}

template <class SRC>
void QRfbSingleColorHextile<SRC>::write(QTcpSocket *socket) const
{
    if (true || encoder->newBg) {
        const int bpp = encoder->server->clientBytesPerPixel();
        const int padding = 3;
        QVarLengthArray<char> buffer(padding + 1 + bpp);
        buffer[padding] = 2; // BackgroundSpecified
        encoder->server->convertPixels(buffer.data() + padding + 1,
                                       reinterpret_cast<char*>(&encoder->bg),
                                       1);
        socket->write(buffer.data() + padding, bpp + 1);
//        encoder->newBg = false;
    } else {
        char subenc = 0;
        socket->write(&subenc, 1);
    }
}

template <class SRC>
bool QRfbDualColorHextile<SRC>::read(const uchar *data,
                                     int width, int height, int stride)
{
    const SRC *ptr = reinterpret_cast<const SRC*>(data);
    const int linestep = (stride / sizeof(SRC)) - width;

    SRC c1;
    SRC c2 = 0;
    int n1 = 0;
    int n2 = 0;
    int x = 0;
    int y = 0;

    c1 = *ptr;

    // find second color
    while (y < height) {
        while (x < width) {
            if (*ptr == c1) {
                ++n1;
            } else {
                c2 = *ptr;
                goto found_second_color;
            }
            ++ptr;
            ++x;
        }
        x = 0;
        ptr += linestep;
        ++y;
    }

found_second_color:
    // finish counting
    while (y < height) {
        while (x < width) {
            if (*ptr == c1) {
                ++n1;
            } else if (*ptr == c2) {
                ++n2;
            } else {
                return false;
            }
            ++ptr;
            ++x;
        }
        x = 0;
        ptr += linestep;
        ++y;
    }

    if (n2 > n1) {
        const quint32 tmpC = c1;
        c1 = c2;
        c2 = tmpC;
    }

    encoder->newBg |= (c1 != encoder->bg);
    encoder->newFg |= (c2 != encoder->fg);

    encoder->bg = c1;
    encoder->fg = c2;

    // create map
    bool inRect = false;
    numRects = 0;
    ptr = reinterpret_cast<const SRC*>(data);
    for (y = 0; y < height; ++y) {
        for (x = 0; x < width; ++x) {
            if (inRect && *ptr == encoder->bg) {
                // rect finished
                setWidth(x - lastx());
                next();
                inRect = false;
            } else if (!inRect && *ptr == encoder->fg) {
                // rect start
                setX(x);
                setY(y);
                setHeight(1);
                inRect = true;
            }
            ++ptr;
        }
        if (inRect) {
            // finish rect
            setWidth(width - lastx());
            next();
            inRect = false;
        }
        ptr += linestep;
    }

    return true;
}

template <class SRC>
void QRfbDualColorHextile<SRC>::write(QTcpSocket *socket) const
{
    const int bpp = encoder->server->clientBytesPerPixel();
    const int padding = 3;
    QVarLengthArray<char> buffer(padding + 2 * bpp + sizeof(char) + sizeof(numRects));
    char &subenc = buffer[padding];
    int n = padding + sizeof(subenc);

    subenc = 0x8; // AnySubrects

    if (encoder->newBg) {
        subenc |= 0x2; // Background
        encoder->server->convertPixels(buffer.data() + n, (char*)&encoder->bg, 1);
        n += bpp;
//        encoder->newBg = false;
    }

    if (encoder->newFg) {
        subenc |= 0x4; // Foreground
        encoder->server->convertPixels(buffer.data() + n, (char*)&encoder->fg, 1);
        n += bpp;
//        encoder->newFg = false;
    }
    buffer[n] = numRects;
    n += sizeof(numRects);

    socket->write(buffer.data() + padding, n - padding);
    socket->write((char*)rects, numRects * sizeof(Rect));
}

template <class SRC>
void QRfbDualColorHextile<SRC>::next()
{
    for (int r = numRects - 1; r >= 0; --r) {
        if (recty(r) == lasty())
            continue;
        if (recty(r) < lasty() - 1) // only search previous scanline
            break;
        if (rectx(r) == lastx() && width(r) == width(numRects)) {
            ++rects[r].wh;
            return;
        }
    }
    ++numRects;
}

template <class SRC>
inline void QRfbMultiColorHextile<SRC>::setColor(SRC color)
{
    encoder->server->convertPixels(reinterpret_cast<char*>(rect(numRects)),
                                   (const char*)&color, 1);
}

template <class SRC>
inline bool QRfbMultiColorHextile<SRC>::beginRect()
{
    if ((rects.size() + bpp + 2) > maxRectsSize)
        return false;
    rects.resize(rects.size() + bpp + 2);
    return true;
}

template <class SRC>
inline void QRfbMultiColorHextile<SRC>::endRect()
{
    setHeight(numRects, 1);
    ++numRects;
}

template <class SRC>
bool QRfbMultiColorHextile<SRC>::read(const uchar *data,
                                      int width, int height, int stride)
{
    const SRC *ptr = reinterpret_cast<const SRC*>(data);
    const int linestep = (stride / sizeof(SRC)) - width;

    bpp = encoder->server->clientBytesPerPixel();

    if (encoder->newBg)
        encoder->bg = ptr[0];

    const SRC bg = encoder->bg;
    SRC color = bg;
    bool inRect = false;

    numRects = 0;
    rects.clear();

    for (int y = 0; y < height; ++y) {
        for (int x = 0; x < width; ++x) {
            if (inRect && *ptr != color) { // end rect
                setWidth(numRects, x - rectx(numRects));
                endRect();
                inRect = false;
            }

            if (!inRect && *ptr != bg) { // begin rect
                if (!beginRect())
                    return false;
                inRect = true;
                color = *ptr;
                setColor(color);
                setX(numRects, x);
                setY(numRects, y);
            }
            ++ptr;
        }
        if (inRect) { // end rect
            setWidth(numRects, width - rectx(numRects));
            endRect();
            inRect = false;
        }
        ptr += linestep;
    }

    return true;
}

template <class SRC>
void QRfbMultiColorHextile<SRC>::write(QTcpSocket *socket) const
{
    const int padding = 3;
    QVarLengthArray<quint8> buffer(bpp + padding + sizeof(quint8) + sizeof(numRects));

    quint8 &subenc = buffer[padding];
    int n = padding + sizeof(quint8);

    subenc = 8 | 16; // AnySubrects | SubrectsColoured

    if (encoder->newBg) {
        subenc |= 0x2; // Background
        encoder->server->convertPixels(reinterpret_cast<char*>(buffer.data() + n),
                                       reinterpret_cast<const char*>(&encoder->bg),
                                       1);
        n += bpp;
//        encoder->newBg = false;
    }

    buffer[n] = numRects;
    n += sizeof(numRects);

    socket->write(reinterpret_cast<const char*>(buffer.data() + padding),
                  n - padding);
    socket->write(reinterpret_cast<const char*>(rects.constData()),
                  rects.size());
}

bool QVNCServer::pixelConversionNeeded() const
{
    if (!sameEndian)
        return true;

#if Q_BYTE_ORDER == Q_BIG_ENDIAN
    if (qvnc_screen->swapBytes())
        return true;
#endif

    const int screendepth = qvnc_screen->depth();
    if (screendepth != pixelFormat.bitsPerPixel)
        return true;

    switch (screendepth) {
    case 32:
    case 24:
        return false;
    case 18:
        return (pixelFormat.redBits == 6
                && pixelFormat.greenBits == 6
                && pixelFormat.blueBits == 6);
    case 16:
        return (pixelFormat.redBits == 5
                && pixelFormat.greenBits == 6
                && pixelFormat.blueBits == 5);
    case 15:
        return (pixelFormat.redBits == 5
                && pixelFormat.greenBits == 5
                && pixelFormat.blueBits == 5);
    case 12:
        return (pixelFormat.redBits == 4
                && pixelFormat.greenBits == 4
                && pixelFormat.blueBits == 4);
    }
    return true;
}

// count: number of pixels
void QVNCServer::convertPixels(char *dst, const char *src, int count) const
{
    const int screendepth = qvnc_screen->depth();
    const bool isBgr = qvnc_screen->pixelType() == QScreen::BGRPixel;

    // cutoffs
#if Q_BYTE_ORDER == Q_BIG_ENDIAN
    if (!swapBytes)
#endif
    if (sameEndian) {
        if (screendepth == pixelFormat.bitsPerPixel) { // memcpy cutoffs

            switch (screendepth) {
            case 32:
                memcpy(dst, src, count * sizeof(quint32));
                return;
            case 16:
                if (pixelFormat.redBits == 5
                    && pixelFormat.greenBits == 6
                    && pixelFormat.blueBits == 5)
                {
                    memcpy(dst, src, count * sizeof(quint16));
                    return;
                }
            }
        } else if (screendepth == 16 && pixelFormat.bitsPerPixel == 32) {
#if defined(__i386__) // Currently fails on ARM if dst is not 4 byte aligned
            const quint32 *src32 = reinterpret_cast<const quint32*>(src);
            quint32 *dst32 = reinterpret_cast<quint32*>(dst);
            int count32 = count * sizeof(quint16) / sizeof(quint32);
            while (count32--) {
                const quint32 s = *src32++;
                quint32 result1;
                quint32 result2;

                // red
                result1 = ((s & 0xf8000000) | ((s & 0xe0000000) >> 5)) >> 8;
                result2 = ((s & 0x0000f800) | ((s & 0x0000e000) >> 5)) << 8;

                // green
                result1 |= ((s & 0x07e00000) | ((s & 0x06000000) >> 6)) >> 11;
                result2 |= ((s & 0x000007e0) | ((s & 0x00000600) >> 6)) << 5;

                // blue
                result1 |= ((s & 0x001f0000) | ((s & 0x001c0000) >> 5)) >> 13;
                result2 |= ((s & 0x0000001f) | ((s & 0x0000001c) >> 5)) << 3;

                *dst32++ = result2;
                *dst32++ = result1;
            }
            if (count & 0x1) {
                const quint16 *src16 = reinterpret_cast<const quint16*>(src);
                *dst32 = qt_conv16ToRgb(src16[count - 1]);
            }
            return;
#endif
        }
    }

    const int bytesPerPixel = (pixelFormat.bitsPerPixel + 7) / 8;

//    nibble = 0;

    for (int i = 0; i < count; ++i) {
        int r, g, b;

        switch (screendepth) {
#if 0
        case 4: {
            if (!nibble) {
                r = ((*src) & 0x0f) << 4;
            } else {
                r = (*src) & 0xf0;
                src++;
            }
            nibble = !nibble;
            g = b = r;
            break;
        }
#endif
        case 8: {
            QRgb rgb = qvnc_screen->clut()[int(*src)];
            r = qRed(rgb);
            g = qGreen(rgb);
            b = qBlue(rgb);
            src++;
            break;
        }
#ifdef QT_QWS_DEPTH_12
        case 12: {
            quint32 p = quint32(*reinterpret_cast<const qrgb444*>(src));
            r = qRed(p);
            g = qGreen(p);
            b = qBlue(p);
            src += sizeof(qrgb444);
            break;
        }
#endif
#ifdef QT_QWS_DEPTH_15
        case 15: {
            quint32 p = quint32(*reinterpret_cast<const qrgb555*>(src));
            r = qRed(p);
            g = qGreen(p);
            b = qBlue(p);
            src += sizeof(qrgb555);
            break;
        }
#endif
        case 16: {
            quint16 p = *reinterpret_cast<const quint16*>(src);
#if Q_BYTE_ORDER == Q_BIG_ENDIAN
            if (swapBytes)
                p = ((p & 0xff) << 8) | ((p & 0xff00) >> 8);
#endif
            r = (p >> 11) & 0x1f;
            g = (p >> 5) & 0x3f;
            b = p & 0x1f;
            r <<= 3;
            g <<= 2;
            b <<= 3;
            src += sizeof(quint16);
            break;
        }
#ifdef QT_QWS_DEPTH_18
        case 18: {
            quint32 p = quint32(*reinterpret_cast<const qrgb666*>(src));
            r = qRed(p);
            g = qGreen(p);
            b = qBlue(p);
            src += sizeof(qrgb666);
            break;
        }
#endif
#ifdef QT_QWS_DEPTH_24
        case 24: {
            quint32 p = quint32(*reinterpret_cast<const qrgb888*>(src));
            r = qRed(p);
            g = qGreen(p);
            b = qBlue(p);
            src += sizeof(qrgb888);
            break;
        }
#endif
        case 32: {
            quint32 p = *reinterpret_cast<const quint32*>(src);
            r = (p >> 16) & 0xff;
            g = (p >> 8) & 0xff;
            b = p & 0xff;
            src += sizeof(quint32);
            break;
        }
        default: {
            r = g = b = 0;
            qDebug("QVNCServer: don't support %dbpp display", screendepth);
            return;
        }
        }

#if Q_BYTE_ORDER == Q_BIG_ENDIAN
        if (swapBytes ^ isBgr)
#else
        if (isBgr)
#endif
            qSwap(r, b);

        r >>= (8 - pixelFormat.redBits);
        g >>= (8 - pixelFormat.greenBits);
        b >>= (8 - pixelFormat.blueBits);

        int pixel = (r << pixelFormat.redShift) |
                    (g << pixelFormat.greenShift) |
                    (b << pixelFormat.blueShift);

        if (sameEndian || pixelFormat.bitsPerPixel == 8) {
            memcpy(dst, &pixel, bytesPerPixel); // XXX: do a simple for-loop instead?
            dst += bytesPerPixel;
            continue;
        }


        if (QSysInfo::ByteOrder == QSysInfo::BigEndian) {
            switch (pixelFormat.bitsPerPixel) {
            case 16:
                pixel = (((pixel & 0x0000ff00) << 8)  |
                         ((pixel & 0x000000ff) << 24));
                break;
            case 32:
                pixel = (((pixel & 0xff000000) >> 24) |
                         ((pixel & 0x00ff0000) >> 8)  |
                         ((pixel & 0x0000ff00) << 8)  |
                         ((pixel & 0x000000ff) << 24));
                break;
            default:
                qDebug("Cannot handle %d bpp client", pixelFormat.bitsPerPixel);
            }
        } else { // QSysInfo::ByteOrder == QSysInfo::LittleEndian
            switch (pixelFormat.bitsPerPixel) {
            case 16:
                pixel = (((pixel & 0xff000000) >> 8) |
                         ((pixel & 0x00ff0000) << 8));
                break;
            case 32:
                pixel = (((pixel & 0xff000000) >> 24) |
                         ((pixel & 0x00ff0000) >> 8)  |
                         ((pixel & 0x0000ff00) << 8)  |
                         ((pixel & 0x000000ff) << 24));
                break;
            default:
                qDebug("Cannot handle %d bpp client",
                       pixelFormat.bitsPerPixel);
                break;
            }
        }
        memcpy(dst, &pixel, bytesPerPixel); // XXX: simple for-loop instead?
        dst += bytesPerPixel;
    }
}

#ifndef QT_NO_QWS_CURSOR
static void blendCursor(QImage &image, const QRect &imageRect)
{
    const QRect cursorRect = qt_screencursor->boundingRect();
    const QRect intersection = (cursorRect & imageRect);
    const QRect destRect = intersection.translated(-imageRect.topLeft());
    const QRect srcRect = intersection.translated(-cursorRect.topLeft());

    QPainter painter(&image);
    painter.drawImage(destRect, qt_screencursor->image(), srcRect);
    painter.end();
}
#endif // QT_NO_QWS_CURSOR

QVNCDirtyMap::QVNCDirtyMap(QScreen *s)
    : bytesPerPixel(0), numDirty(0), screen(s)
{
    bytesPerPixel = (screen->depth() + 7) / 8;
    bufferWidth = screen->deviceWidth();
    bufferHeight = screen->deviceHeight();
    bufferStride = bufferWidth * bytesPerPixel;
    buffer = new uchar[bufferHeight * bufferStride];

    mapWidth = (bufferWidth + MAP_TILE_SIZE - 1) / MAP_TILE_SIZE;
    mapHeight = (bufferHeight + MAP_TILE_SIZE - 1) / MAP_TILE_SIZE;
    numTiles = mapWidth * mapHeight;
    map = new uchar[numTiles];
}

QVNCDirtyMap::~QVNCDirtyMap()
{
    delete[] map;
    delete[] buffer;
}

void QVNCDirtyMap::reset()
{
    memset(map, 1, numTiles);
    memset(buffer, 0, bufferHeight * bufferStride);
    numDirty = numTiles;
}

inline bool QVNCDirtyMap::dirty(int x, int y) const
{
    return map[y * mapWidth + x];
}

inline void QVNCDirtyMap::setClean(int x, int y)
{
    map[y * mapWidth + x] = 0;
    --numDirty;
}

template <class T>
void QVNCDirtyMapOptimized<T>::setDirty(int tileX, int tileY, bool force)
{
    static bool alwaysForce = qgetenv("QT_VNC_NO_COMPAREBUFFER").toInt();
    if (alwaysForce)
        force = true;

    bool changed = false;

    if (!force) {
        const int lstep = screen->linestep();
        const int startX = tileX * MAP_TILE_SIZE;
        const int startY = tileY * MAP_TILE_SIZE;
        const uchar *scrn = screen->base()
                            + startY * lstep + startX * bytesPerPixel;
        uchar *old = buffer + startY * bufferStride + startX * sizeof(T);

        const int tileHeight = (startY + MAP_TILE_SIZE > bufferHeight ?
                                bufferHeight - startY : MAP_TILE_SIZE);
        const int tileWidth = (startX + MAP_TILE_SIZE > bufferWidth ?
                               bufferWidth - startX : MAP_TILE_SIZE);
        const bool doInlines = (tileWidth == MAP_TILE_SIZE);

        int y = tileHeight;

        if (doInlines) { // hw: memcmp/memcpy is inlined when using constants
            while (y) {
                if (memcmp(old, scrn, sizeof(T) * MAP_TILE_SIZE)) {
                    changed = true;
                    break;
                }
                scrn += lstep;
                old += bufferStride;
                --y;
            }

            while (y) {
                memcpy(old, scrn, sizeof(T) * MAP_TILE_SIZE);
                scrn += lstep;
                old += bufferStride;
                --y;
            }
        } else {
            while (y) {
                if (memcmp(old, scrn, sizeof(T) * tileWidth)) {
                    changed = true;
                    break;
                }
                scrn += lstep;
                old += bufferStride;
                --y;
            }

            while (y) {
                memcpy(old, scrn, sizeof(T) * tileWidth);
                scrn += lstep;
                old += bufferStride;
                --y;
            }
        }
    }

    const int mapIndex = tileY * mapWidth + tileX;
    if ((force || changed) && !map[mapIndex]) {
        map[mapIndex] = 1;
        ++numDirty;
    }
}

template <class SRC>
QRfbHextileEncoder<SRC>::QRfbHextileEncoder(QVNCServer *s)
    : QRfbEncoder(s),
      singleColorHextile(this), dualColorHextile(this), multiColorHextile(this)
{
}

/*
    \internal
    Send dirty rects using hextile encoding.
*/
template <class SRC>
void QRfbHextileEncoder<SRC>::write()
{
    QWSDisplay::grab(true);

    QVNCDirtyMap *map = server->dirtyMap();
    QTcpSocket *socket = server->clientSocket();

    const quint32 encoding = htonl(5); // hextile encoding
    const int bytesPerPixel = server->clientBytesPerPixel();

    {
        const char tmp[2] = { 0, 0 }; // msg type, padding
        socket->write(tmp, sizeof(tmp));
    }
    {
        const quint16 count = htons(map->numDirty);
        socket->write((char *)&count, sizeof(count));
    }

    if (map->numDirty <= 0) {
        QWSDisplay::ungrab();
        return;
    }

    newBg = true;
    newFg = true;

    const QImage screenImage = server->screenImage();
    QRfbRect rect(0, 0, MAP_TILE_SIZE, MAP_TILE_SIZE);

    for (int y = 0; y < map->mapHeight; ++y) {
        if (rect.y + MAP_TILE_SIZE > server->screen()->height())
            rect.h = server->screen()->height() - rect.y;
        rect.w = MAP_TILE_SIZE;
        for (int x = 0; x < map->mapWidth; ++x) {
            if (!map->dirty(x, y))
                continue;
            map->setClean(x, y);

            rect.x = x * MAP_TILE_SIZE;
            if (rect.x + MAP_TILE_SIZE > server->screen()->deviceWidth())
                rect.w = server->screen()->deviceWidth() - rect.x;
            rect.write(socket);

            socket->write((char *)&encoding, sizeof(encoding));

            const uchar *screendata = screenImage.scanLine(rect.y)
                                      + rect.x * screenImage.depth() / 8;
            int linestep = screenImage.bytesPerLine();

#ifndef QT_NO_QWS_CURSOR
            // hardware cursors must be blended with the screen memory
            const bool doBlendCursor = qt_screencursor
                                       && !server->hasClientCursor()
                                       && qt_screencursor->isAccelerated();
            QImage tileImage;
            if (doBlendCursor) {
                const QRect tileRect(rect.x, rect.y, rect.w, rect.h);
                const QRect cursorRect = qt_screencursor->boundingRect()
                                         .translated(-server->screen()->offset());
                if (tileRect.intersects(cursorRect)) {
                    tileImage = screenImage.copy(tileRect);
                    blendCursor(tileImage,
                                tileRect.translated(server->screen()->offset()));
                    screendata = tileImage.bits();
                    linestep = tileImage.bytesPerLine();
                }
            }
#endif // QT_NO_QWS_CURSOR

            if (singleColorHextile.read(screendata, rect.w, rect.h, linestep)) {
                singleColorHextile.write(socket);
            } else if (dualColorHextile.read(screendata, rect.w, rect.h, linestep)) {
                dualColorHextile.write(socket);
            } else if (multiColorHextile.read(screendata, rect.w, rect.h, linestep)) {
                multiColorHextile.write(socket);
            } else if (server->doPixelConversion()) {
                const int bufferSize = rect.w * rect.h * bytesPerPixel + 1;
                const int padding = sizeof(quint32) - sizeof(char);
                buffer.resize(bufferSize + padding);

                buffer[padding] = 1; // Raw subencoding

                // convert pixels
                char *b = buffer.data() + padding + 1;
                const int bstep = rect.w * bytesPerPixel;
                for (int i = 0; i < rect.h; ++i) {
                    server->convertPixels(b, (const char*)screendata, rect.w);
                    screendata += linestep;
                    b += bstep;
                }
                socket->write(buffer.constData() + padding, bufferSize);
            } else {
                quint8 subenc = 1; // Raw subencoding
                socket->write((char *)&subenc, 1);

                // send pixels
                for (int i = 0; i < rect.h; ++i) {
                    socket->write((const char*)screendata,
                                  rect.w * bytesPerPixel);
                    screendata += linestep;
                }
            }
        }
        if (socket->state() == QAbstractSocket::UnconnectedState)
            break;
        rect.y += MAP_TILE_SIZE;
    }
    socket->flush();
    Q_ASSERT(map->numDirty == 0);

    QWSDisplay::ungrab();
}

void QRfbRawEncoder::write()
{
    QWSDisplay::grab(false);

    QVNCDirtyMap *map = server->dirtyMap();
    QTcpSocket *socket = server->clientSocket();

    const int bytesPerPixel = server->clientBytesPerPixel();

    // create a region from the dirty rects and send the region's merged rects.
    QRegion rgn;
    if (map) {
        for (int y = 0; y < map->mapHeight; ++y) {
            for (int x = 0; x < map->mapWidth; ++x) {
                if (!map->dirty(x, y))
                    continue;
                rgn += QRect(x * MAP_TILE_SIZE, y * MAP_TILE_SIZE,
                             MAP_TILE_SIZE, MAP_TILE_SIZE);
                map->setClean(x, y);
            }
        }

        rgn &= QRect(0, 0, server->screen()->deviceWidth(),
                     server->screen()->deviceHeight());
    }
    const QVector<QRect> rects = rgn.rects();

    {
        const char tmp[2] = { 0, 0 }; // msg type, padding
        socket->write(tmp, sizeof(tmp));
    }

    {
        const quint16 count = htons(rects.size());
        socket->write((char *)&count, sizeof(count));
    }

    if (rects.size() <= 0) {
        QWSDisplay::ungrab();
        return;
    }

    const QImage screenImage = server->screenImage();

    for (int i = 0; i < rects.size(); ++i) {
        const QRect tileRect = rects.at(i);
        const QRfbRect rect(tileRect.x(), tileRect.y(),
                            tileRect.width(), tileRect.height());
        rect.write(socket);

        const quint32 encoding = htonl(0); // raw encoding
        socket->write((char *)&encoding, sizeof(encoding));

        int linestep = screenImage.bytesPerLine();
        const uchar *screendata = screenImage.scanLine(rect.y)
                                  + rect.x * screenImage.depth() / 8;

#ifndef QT_NO_QWS_CURSOR
        // hardware cursors must be blended with the screen memory
        const bool doBlendCursor = qt_screencursor
                                   && !server->hasClientCursor()
                                   && qt_screencursor->isAccelerated();
        QImage tileImage;
        if (doBlendCursor) {
            const QRect cursorRect = qt_screencursor->boundingRect()
                                     .translated(-server->screen()->offset());
            if (tileRect.intersects(cursorRect)) {
                tileImage = screenImage.copy(tileRect);
                blendCursor(tileImage,
                            tileRect.translated(server->screen()->offset()));
                screendata = tileImage.bits();
                linestep = tileImage.bytesPerLine();
            }
        }
#endif // QT_NO_QWS_CURSOR

        if (server->doPixelConversion()) {
            const int bufferSize = rect.w * rect.h * bytesPerPixel;
            if (bufferSize > buffer.size())
                buffer.resize(bufferSize);

            // convert pixels
            char *b = buffer.data();
            const int bstep = rect.w * bytesPerPixel;
            for (int i = 0; i < rect.h; ++i) {
                server->convertPixels(b, (const char*)screendata, rect.w);
                screendata += linestep;
                b += bstep;
            }
            socket->write(buffer.constData(), bufferSize);
        } else {
            for (int i = 0; i < rect.h; ++i) {
                socket->write((const char*)screendata, rect.w * bytesPerPixel);
                screendata += linestep;
            }
        }
        if (socket->state() == QAbstractSocket::UnconnectedState)
            break;
    }
    socket->flush();

    QWSDisplay::ungrab();
}

inline QImage QVNCServer::screenImage() const
{
    return QImage(qvnc_screen->base(), qvnc_screen->deviceWidth(),
                  qvnc_screen->deviceHeight(), qvnc_screen->linestep(),
                  qvnc_screen->pixelFormat());
}

void QVNCServer::checkUpdate()
{
    if (!wantUpdate)
        return;

    if (dirtyCursor) {
#ifndef QT_NO_QWS_CURSOR
        Q_ASSERT(qvnc_cursor);
        qvnc_cursor->write();
#endif
        dirtyCursor = false;
        wantUpdate = false;
        return;
    }

    if (dirtyMap()->numDirty > 0) {
        if (encoder)
            encoder->write();
        wantUpdate = false;
    }
}

void QVNCServer::discardClient()
{
    timer->stop();
    state = Unconnected;
    delete encoder;
    encoder = 0;
#ifndef QT_NO_QWS_CURSOR
    delete qvnc_cursor;
    qvnc_cursor = 0;
#endif
    if (!qvnc_screen->screen() && !qvnc_screen->d_ptr->noDisablePainting && QWSServer::instance())
        QWSServer::instance()->enablePainting(false);
}


//===========================================================================

/*!
    \class QVNCScreen
    \internal
    \ingroup qws

    \brief The QVNCScreen class implements a screen driver for VNC
    servers.

    Note that this class is only available in \l{Qt for Embedded Linux}.
    Custom screen drivers can be added by subclassing the QScreen
    class, using the QScreenDriverFactory class to dynamically load
    the driver into the application.

    The VNC protocol allows you to view and interact with the
    computer's display from anywhere on the network. See the
    \l{The VNC Protocol and Qt for Embedded Linux}{VNC protocol}
    documentation for more details.

    The default implementation of QVNCScreen inherits QLinuxFbScreen,
    but any QScreen subclass, or QScreen itself, can serve as its base
    class. This is easily achieved by manipulating the \c
    VNCSCREEN_BASE definition in the header file.

    \sa QScreen, {Running Applications}
*/

/*!
    \fn QVNCScreen::QVNCScreen(int displayId)

    Constructs a QVNCScreen object. The \a displayId argument
    identifies the Qt for Embedded Linux server to connect to.
*/
QVNCScreen::QVNCScreen(int display_id)
    : QProxyScreen(display_id, VNCClass)
{
    d_ptr = new QVNCScreenPrivate(this);
}

/*!
    Destroys this QVNCScreen object.
*/
QVNCScreen::~QVNCScreen()
{
    delete d_ptr;
}

/*!
    \reimp
*/
void QVNCScreen::setDirty(const QRect &rect)
{
    d_ptr->setDirty(rect);
}

void QVNCScreenPrivate::setDirty(const QRect& rect, bool force)
{
    if (rect.isEmpty())
        return;

    if (q_ptr->screen())
        q_ptr->screen()->setDirty(rect);

    if (!vncServer || !vncServer->isConnected())
        return;

    const QRect r = rect.translated(-q_ptr->offset());
    const int x1 = r.x() / MAP_TILE_SIZE;
    int y = r.y() / MAP_TILE_SIZE;
    for (; (y <= r.bottom() / MAP_TILE_SIZE) && y < dirty->mapHeight; y++)
        for (int x = x1; (x <= r.right() / MAP_TILE_SIZE) && x < dirty->mapWidth; x++)
            dirty->setDirty(x, y, force);

    vncServer->setDirty();
}

static int getDisplayId(const QString &spec)
{
    QRegExp regexp(QLatin1String(":(\\d+)\\b"));
    if (regexp.lastIndexIn(spec) != -1) {
        const QString capture = regexp.cap(1);
        return capture.toInt();
    }
    return 0;
}

/*!
    \reimp
*/
bool QVNCScreen::connect(const QString &displaySpec)
{
    QString dspec = displaySpec;
    if (dspec.startsWith(QLatin1String("vnc:"), Qt::CaseInsensitive))
        dspec = dspec.mid(QString::fromLatin1("vnc:").size());
    else if (dspec.compare(QLatin1String("vnc"), Qt::CaseInsensitive) == 0)
        dspec = QString();

    const QString displayIdSpec = QString::fromLatin1(" :%1").arg(displayId);
    if (dspec.endsWith(displayIdSpec))
        dspec = dspec.left(dspec.size() - displayIdSpec.size());

    QStringList args = dspec.split(QLatin1Char(':'),
                                   QString::SkipEmptyParts);
    QRegExp refreshRegexp(QLatin1String("^refreshrate=(\\d+)$"));
    int index = args.indexOf(refreshRegexp);
    if (index >= 0) {
        d_ptr->refreshRate = refreshRegexp.cap(1).toInt();
        args.removeAt(index);
        dspec = args.join(QLatin1String(":"));
    }

    QString driver = dspec;
    int colon = driver.indexOf(QLatin1Char(':'));
    if (colon >= 0)
        driver.truncate(colon);

    if (QScreenDriverFactory::keys().contains(driver, Qt::CaseInsensitive)) {
        const int id = getDisplayId(dspec);
        QScreen *s = qt_get_screen(id, dspec.toLatin1().constData());
        if (s->pixelFormat() == QImage::Format_Indexed8
            || s->pixelFormat() == QImage::Format_Invalid && s->depth() == 8)
            qFatal("QVNCScreen: unsupported screen format");
        setScreen(s);
    } else { // create virtual screen
#if Q_BYTE_ORDER == Q_BIG_ENDIAN
        QScreen::setFrameBufferLittleEndian(false);
#endif

        d = qgetenv("QWS_DEPTH").toInt();
        if (!d)
            d = 16;

        QByteArray str = qgetenv("QWS_SIZE");
        if(!str.isEmpty()) {
            sscanf(str.constData(), "%dx%d", &w, &h);
            dw = w;
            dh = h;
        } else {
            dw = w = 640;
            dh = h = 480;
        }

        const QStringList args = displaySpec.split(QLatin1Char(':'),
                                                   QString::SkipEmptyParts);

        if (args.contains(QLatin1String("paintonscreen"), Qt::CaseInsensitive))
            d_ptr->doOnScreenSurface = true;

        QRegExp depthRegexp(QLatin1String("^depth=(\\d+)$"));
        if (args.indexOf(depthRegexp) != -1)
            d = depthRegexp.cap(1).toInt();

        QRegExp sizeRegexp(QLatin1String("^size=(\\d+)x(\\d+)$"));
        if (args.indexOf(sizeRegexp) != -1) {
            dw = w = sizeRegexp.cap(1).toInt();
            dh = h = sizeRegexp.cap(2).toInt();
        }

        // Handle display physical size spec.
        QRegExp mmWidthRegexp(QLatin1String("^mmWidth=?(\\d+)$"));
        if (args.indexOf(mmWidthRegexp) != -1) {
            const int mmWidth = mmWidthRegexp.cap(1).toInt();
            if (mmWidth > 0)
                d_ptr->dpiX = dw * 25.4 / mmWidth;
        }
        QRegExp mmHeightRegexp(QLatin1String("^mmHeight=?(\\d+)$"));
        if (args.indexOf(mmHeightRegexp) != -1) {
            const int mmHeight = mmHeightRegexp.cap(1).toInt();
            if (mmHeight > 0)
                d_ptr->dpiY = dh * 25.4 / mmHeight;
        }
        QRegExp dpiRegexp(QLatin1String("^dpi=(\\d+)(?:,(\\d+))?$"));
        if (args.indexOf(dpiRegexp) != -1) {
            const qreal dpiX = dpiRegexp.cap(1).toFloat();
            const qreal dpiY = dpiRegexp.cap(2).toFloat();
            if (dpiX > 0)
                d_ptr->dpiX = dpiX;
            d_ptr->dpiY = (dpiY > 0 ? dpiY : dpiX);
        }

        if (args.contains(QLatin1String("noDisablePainting")))
            d_ptr->noDisablePainting = true;

        QWSServer::setDefaultMouse("None");
        QWSServer::setDefaultKeyboard("None");

        d_ptr->configure();
    }

    // XXX
    qt_screen = this;

    return true;
}

/*!
    \reimp
*/
void QVNCScreen::disconnect()
{
    QProxyScreen::disconnect();
#if !defined(QT_NO_QWS_MULTIPROCESS) && !defined(QT_NO_SHAREDMEMORY)
    d_ptr->shm.detach();
#endif
}

/*!
    \reimp
*/
bool QVNCScreen::initDevice()
{
    if (!QProxyScreen::screen() && d == 4) {
        screencols = 16;
        int val = 0;
        for (int idx = 0; idx < 16; idx++, val += 17) {
            screenclut[idx] = qRgb(val, val, val);
        }
    }
    d_ptr->vncServer = new QVNCServer(this, displayId);
    d_ptr->vncServer->setRefreshRate(d_ptr->refreshRate);

    switch (depth()) {
#ifdef QT_QWS_DEPTH_32
    case 32:
        d_ptr->dirty = new QVNCDirtyMapOptimized<quint32>(this);
        break;
#endif
#ifdef QT_QWS_DEPTH_24
    case 24:
        d_ptr->dirty = new QVNCDirtyMapOptimized<qrgb888>(this);
        break;
#endif
#ifdef QT_QWS_DEPTH_18
    case 18:
        d_ptr->dirty = new QVNCDirtyMapOptimized<qrgb666>(this);
        break;
#endif
#ifdef QT_QWS_DEPTH_16
    case 16:
        d_ptr->dirty = new QVNCDirtyMapOptimized<quint16>(this);
        break;
#endif
#ifdef QT_QWS_DEPTH_15
    case 15:
        d_ptr->dirty = new QVNCDirtyMapOptimized<qrgb555>(this);
        break;
#endif
#ifdef QT_QWS_DEPTH_12
    case 12:
        d_ptr->dirty = new QVNCDirtyMapOptimized<qrgb444>(this);
        break;
#endif
#ifdef QT_QWS_DEPTH_8
    case 8:
        d_ptr->dirty = new QVNCDirtyMapOptimized<quint8>(this);
        break;
#endif
    default:
        qWarning("QVNCScreen::initDevice: No support for screen depth %d",
                 depth());
        d_ptr->dirty = 0;
        return false;
    }


    const bool ok = QProxyScreen::initDevice();
#ifndef QT_NO_QWS_CURSOR
    qt_screencursor = new QVNCCursor(this);
#endif
    if (QProxyScreen::screen())
        return ok;

    // Disable painting if there is only 1 display and nothing is attached to the VNC server
    if (!d_ptr->noDisablePainting)
        QWSServer::instance()->enablePainting(false);

    return true;
}

/*!
    \reimp
*/
void QVNCScreen::shutdownDevice()
{
    QProxyScreen::shutdownDevice();
    delete d_ptr->vncServer;
    delete d_ptr->dirty;
}

QT_END_NAMESPACE

#endif // QT_NO_QWS_VNC