diff -r 000000000000 -r 1918ee327afb src/gui/embedded/qwssharedmemory.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/gui/embedded/qwssharedmemory.cpp Mon Jan 11 14:00:40 2010 +0000 @@ -0,0 +1,185 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtGui module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** 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. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qwssharedmemory_p.h" + +#if !defined(QT_NO_QWS_MULTIPROCESS) + +#include + +QT_BEGIN_NAMESPACE + +QWSSharedMemory::QWSSharedMemory() + : shmBase(0), shmSize(0), character(0), shmId(-1), key(-1) +{ +} + + +QWSSharedMemory::~QWSSharedMemory() +{ + detach(); +} + +/* + man page says: + On Linux, it is possible to attach a shared memory segment even if it + is already marked to be deleted. However, POSIX.1-2001 does not spec- + ify this behaviour and many other implementations do not support it. +*/ + +bool QWSSharedMemory::create(int size) +{ + if (shmId != -1) + detach(); + shmId = shmget(IPC_PRIVATE, size, IPC_CREAT|0600); + + if (shmId == -1) { +#ifdef QT_SHM_DEBUG + perror("QWSSharedMemory::create allocating shared memory"); + qWarning("Error allocating shared memory of size %d", size); +#endif + return false; + } + shmBase = shmat(shmId,0,0); + shmctl(shmId, IPC_RMID, 0); + if (shmBase == (void*)-1) { +#ifdef QT_SHM_DEBUG + perror("QWSSharedMemory::create attaching to shared memory"); + qWarning("Error attaching to shared memory id %d", shmId); +#endif + shmBase = 0; + return false; + } + return true; +} + +bool QWSSharedMemory::attach(int id) +{ + if (shmId == id) + return id != -1; + if (shmId != -1) + detach(); + + shmBase = shmat(id,0,0); + if (shmBase == (void*)-1) { +#ifdef QT_SHM_DEBUG + perror("QWSSharedMemory::attach attaching to shared memory"); + qWarning("Error attaching to shared memory 0x%x of size %d", + id, size()); +#endif + shmBase = 0; + return false; + } + shmId = id; + return true; +} + + +void QWSSharedMemory::detach () +{ + if (!shmBase) + return; + shmdt (shmBase); + shmBase = 0; + shmSize = 0; + shmId = -1; +} + +void QWSSharedMemory::setPermissions (mode_t mode) +{ + struct shmid_ds shm; + shmctl (shmId, IPC_STAT, &shm); + shm.shm_perm.mode = mode; + shmctl (shmId, IPC_SET, &shm); +} + +int QWSSharedMemory::size () const +{ + struct shmid_ds shm; + shmctl (shmId, IPC_STAT, &shm); + return shm.shm_segsz; +} + + +// old API + + + +QWSSharedMemory::QWSSharedMemory (int size, const QString &filename, char c) +{ + shmSize = size; + shmFile = filename; + shmBase = 0; + shmId = -1; + character = c; + key = ftok (shmFile.toLatin1().constData(), c); +} + + + +bool QWSSharedMemory::create () +{ + shmId = shmget (key, shmSize, IPC_CREAT | 0666); + return (shmId != -1); +} + +void QWSSharedMemory::destroy () +{ + if (shmId != -1) + shmctl(shmId, IPC_RMID, 0); +} + +bool QWSSharedMemory::attach () +{ + if (shmId == -1) + shmId = shmget (key, shmSize, 0); + + shmBase = shmat (shmId, 0, 0); + if ((long)shmBase == -1) + shmBase = 0; + + return (long)shmBase != 0; +} + + +QT_END_NAMESPACE + +#endif // QT_NO_QWS_MULTIPROCESS