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diff --git a/src/corelib/kernel/qsharedmemory_systemv.cpp b/src/corelib/kernel/qsharedmemory_systemv.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** 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 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qplatformdefs.h"
+
+#include "qsharedmemory.h"
+#include "qsharedmemory_p.h"
+#include "qsystemsemaphore.h"
+#include <qdir.h>
+#include <qdebug.h>
+
+#include <errno.h>
+
+#ifndef QT_POSIX_IPC
+
+#ifndef QT_NO_SHAREDMEMORY
+#include <sys/types.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#endif //QT_NO_SHAREDMEMORY
+
+#include "private/qcore_unix_p.h"
+
+#ifndef QT_NO_SHAREDMEMORY
+QT_BEGIN_NAMESPACE
+
+/*!
+ \internal
+
+ If not already made create the handle used for accessing the shared memory.
+*/
+key_t QSharedMemoryPrivate::handle()
+{
+ // already made
+ if (unix_key)
+ return unix_key;
+
+ // don't allow making handles on empty keys
+ if (nativeKey.isEmpty()) {
+ errorString = QSharedMemory::tr("%1: key is empty").arg(QLatin1String("QSharedMemory::handle:"));
+ error = QSharedMemory::KeyError;
+ return 0;
+ }
+
+ // ftok requires that an actual file exists somewhere
+ if (!QFile::exists(nativeKey)) {
+ errorString = QSharedMemory::tr("%1: UNIX key file doesn't exist").arg(QLatin1String("QSharedMemory::handle:"));
+ error = QSharedMemory::NotFound;
+ return 0;
+ }
+
+ unix_key = ftok(QFile::encodeName(nativeKey).constData(), 'Q');
+ if (-1 == unix_key) {
+ errorString = QSharedMemory::tr("%1: ftok failed").arg(QLatin1String("QSharedMemory::handle:"));
+ error = QSharedMemory::KeyError;
+ unix_key = 0;
+ }
+ return unix_key;
+}
+
+#endif // QT_NO_SHAREDMEMORY
+
+#if !(defined(QT_NO_SHAREDMEMORY) && defined(QT_NO_SYSTEMSEMAPHORE))
+/*!
+ \internal
+ Creates the unix file if needed.
+ returns \c true if the unix file was created.
+
+ -1 error
+ 0 already existed
+ 1 created
+ */
+int QSharedMemoryPrivate::createUnixKeyFile(const QString &fileName)
+{
+ int fd = qt_safe_open(QFile::encodeName(fileName).constData(),
+ O_EXCL | O_CREAT | O_RDWR, 0640);
+ if (-1 == fd) {
+ if (errno == EEXIST)
+ return 0;
+ return -1;
+ } else {
+ close(fd);
+ }
+ return 1;
+}
+#endif // QT_NO_SHAREDMEMORY && QT_NO_SYSTEMSEMAPHORE
+
+#ifndef QT_NO_SHAREDMEMORY
+
+bool QSharedMemoryPrivate::cleanHandle()
+{
+ unix_key = 0;
+ return true;
+}
+
+bool QSharedMemoryPrivate::create(int size)
+{
+ // build file if needed
+ bool createdFile = false;
+ int built = createUnixKeyFile(nativeKey);
+ if (built == -1) {
+ errorString = QSharedMemory::tr("%1: unable to make key").arg(QLatin1String("QSharedMemory::handle:"));
+ error = QSharedMemory::KeyError;
+ return false;
+ }
+ if (built == 1) {
+ createdFile = true;
+ }
+
+ // get handle
+ if (!handle()) {
+ if (createdFile)
+ QFile::remove(nativeKey);
+ return false;
+ }
+
+ // create
+ if (-1 == shmget(unix_key, size, 0600 | IPC_CREAT | IPC_EXCL)) {
+ QString function = QLatin1String("QSharedMemory::create");
+ switch (errno) {
+ case EINVAL:
+ errorString = QSharedMemory::tr("%1: system-imposed size restrictions").arg(QLatin1String("QSharedMemory::handle"));
+ error = QSharedMemory::InvalidSize;
+ break;
+ default:
+ setErrorString(function);
+ }
+ if (createdFile && error != QSharedMemory::AlreadyExists)
+ QFile::remove(nativeKey);
+ return false;
+ }
+
+ return true;
+}
+
+bool QSharedMemoryPrivate::attach(QSharedMemory::AccessMode mode)
+{
+ // grab the shared memory segment id
+ int id = shmget(unix_key, 0, (mode == QSharedMemory::ReadOnly ? 0400 : 0600));
+ if (-1 == id) {
+ setErrorString(QLatin1String("QSharedMemory::attach (shmget)"));
+ return false;
+ }
+
+ // grab the memory
+ memory = shmat(id, 0, (mode == QSharedMemory::ReadOnly ? SHM_RDONLY : 0));
+ if ((void*) - 1 == memory) {
+ memory = 0;
+ setErrorString(QLatin1String("QSharedMemory::attach (shmat)"));
+ return false;
+ }
+
+ // grab the size
+ shmid_ds shmid_ds;
+ if (!shmctl(id, IPC_STAT, &shmid_ds)) {
+ size = (int)shmid_ds.shm_segsz;
+ } else {
+ setErrorString(QLatin1String("QSharedMemory::attach (shmctl)"));
+ return false;
+ }
+
+ return true;
+}
+
+bool QSharedMemoryPrivate::detach()
+{
+ // detach from the memory segment
+ if (-1 == shmdt(memory)) {
+ QString function = QLatin1String("QSharedMemory::detach");
+ switch (errno) {
+ case EINVAL:
+ errorString = QSharedMemory::tr("%1: not attached").arg(function);
+ error = QSharedMemory::NotFound;
+ break;
+ default:
+ setErrorString(function);
+ }
+ return false;
+ }
+ memory = 0;
+ size = 0;
+
+ // Get the number of current attachments
+ int id = shmget(unix_key, 0, 0400);
+ cleanHandle();
+
+ struct shmid_ds shmid_ds;
+ if (0 != shmctl(id, IPC_STAT, &shmid_ds)) {
+ switch (errno) {
+ case EINVAL:
+ return true;
+ default:
+ return false;
+ }
+ }
+ // If there are no attachments then remove it.
+ if (shmid_ds.shm_nattch == 0) {
+ // mark for removal
+ if (-1 == shmctl(id, IPC_RMID, &shmid_ds)) {
+ setErrorString(QLatin1String("QSharedMemory::remove"));
+ switch (errno) {
+ case EINVAL:
+ return true;
+ default:
+ return false;
+ }
+ }
+
+ // remove file
+ if (!QFile::remove(nativeKey))
+ return false;
+ }
+ return true;
+}
+
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_SHAREDMEMORY
+
+#endif // QT_POSIX_IPC