source: trunk/tools/qvfb/qvfbshmem.cpp@ 1039

/****************************************************************************
**
** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation ([email protected])
**
** This file is part of the tools applications 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 "qlock_p.h"

#include "qvfbshmem.h"
#include "qvfbhdr.h"

#include <QFile>
#include <QTimer>

#include <stdlib.h>
#include <unistd.h>
#include <sys/ipc.h>
#include <sys/types.h>
#include <sys/shm.h>
#include <sys/stat.h>
#include <sys/sem.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <errno.h>
#include <math.h>

QT_BEGIN_NAMESPACE

#ifdef Q_WS_QWS
#error qvfb must be compiled with  the Qt for X11 package
#endif

// Get the name of the directory where Qt for Embedded Linux temporary data should
// live.
static QString qws_dataDir(int qws_display_id)
{
    QByteArray dataDir = QT_VFB_DATADIR(qws_display_id).toLocal8Bit();
    if (mkdir(dataDir, 0700)) {
        if (errno != EEXIST) {
            qFatal("Cannot create Qt for Embedded Linux data directory: %s", dataDir.constData());
        }
    }

    struct stat buf;
    if (lstat(dataDir, &buf))
        qFatal("stat failed for Qt for Embedded Linux data directory: %s", dataDir.constData());

    if (!S_ISDIR(buf.st_mode))
        qFatal("%s is not a directory", dataDir.constData());
    if (buf.st_uid != getuid())
        qFatal("Qt for Embedded Linux data directory is not owned by user %uh", getuid());

    if ((buf.st_mode & 0677) != 0600)
        qFatal("Qt for Embedded Linux data directory has incorrect permissions: %s", dataDir.constData());
    dataDir += "/";

    return QString(dataDir);
}


static QString displayPipe;
static QString displayPiped;
class DisplayLock
{
public:
    DisplayLock() : qlock(0) {
        if (QFile::exists(displayPiped)) {
            qlock = new QLock(displayPipe, 'd', false);
            qlock->lock(QLock::Read);
        }
    }
    ~DisplayLock() {
        if (qlock) {
            qlock->unlock();
            delete qlock;
            qlock = 0;
        }
    }
private:
    QLock *qlock;
};

QShMemViewProtocol::QShMemViewProtocol(int displayid, const QSize &s,
                                       int d, QObject *parent)
    : QVFbViewProtocol(displayid, parent), hdr(0), dataCache(0), lockId(-1),
      windowId(0)
{
    int w = s.width();