diff options
Diffstat (limited to '3rdparty/qtsingleapplication/qtlockedfile_win.cpp')
-rw-r--r-- | 3rdparty/qtsingleapplication/qtlockedfile_win.cpp | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/3rdparty/qtsingleapplication/qtlockedfile_win.cpp b/3rdparty/qtsingleapplication/qtlockedfile_win.cpp new file mode 100644 index 0000000..d4bf9e1 --- /dev/null +++ b/3rdparty/qtsingleapplication/qtlockedfile_win.cpp @@ -0,0 +1,213 @@ +/**************************************************************************** +** +** 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 a Qt Solutions component. +** +** Commercial Usage +** Licensees holding valid Qt Commercial licenses may use this file in +** accordance with the Qt Solutions 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. +** +** Please note Third Party Software included with Qt Solutions may impose +** additional restrictions and it is the user's responsibility to ensure +** that they have met the licensing requirements of the GPL, LGPL, or Qt +** Solutions Commercial license and the relevant license of the Third +** Party Software they are using. +** +** If you are unsure which license is appropriate for your use, please +** contact Nokia at qt-info@nokia.com. +** +****************************************************************************/ + +#include "qtlockedfile.h" +#include <qt_windows.h> +#include <QtCore/QFileInfo> + +#define MUTEX_PREFIX "QtLockedFile mutex " +// Maximum number of concurrent read locks. Must not be greater than MAXIMUM_WAIT_OBJECTS +#define MAX_READERS MAXIMUM_WAIT_OBJECTS + +Qt::HANDLE QtLockedFile::getMutexHandle(int idx, bool doCreate) +{ + if (mutexname.isEmpty()) { + QFileInfo fi(*this); + mutexname = QString::fromLatin1(MUTEX_PREFIX) + + fi.absoluteFilePath().toLower(); + } + QString mname(mutexname); + if (idx >= 0) + mname += QString::number(idx); + + Qt::HANDLE mutex; + if (doCreate) { + QT_WA( { mutex = CreateMutexW(NULL, FALSE, (TCHAR*)mname.utf16()); }, + { mutex = CreateMutexA(NULL, FALSE, mname.toLocal8Bit().constData()); } ); + if (!mutex) { + qErrnoWarning("QtLockedFile::lock(): CreateMutex failed"); + return 0; + } + } + else { + QT_WA( { mutex = OpenMutexW(SYNCHRONIZE | MUTEX_MODIFY_STATE, FALSE, (TCHAR*)mname.utf16()); }, + { mutex = OpenMutexA(SYNCHRONIZE | MUTEX_MODIFY_STATE, FALSE, mname.toLocal8Bit().constData()); } ); + if (!mutex) { + if (GetLastError() != ERROR_FILE_NOT_FOUND) + qErrnoWarning("QtLockedFile::lock(): OpenMutex failed"); + return 0; + } + } + return mutex; +} + +bool QtLockedFile::waitMutex(Qt::HANDLE mutex, bool doBlock) +{ + Q_ASSERT(mutex); + DWORD res = WaitForSingleObject(mutex, doBlock ? INFINITE : 0); + switch (res) { + case WAIT_OBJECT_0: + case WAIT_ABANDONED: + return true; + break; + case WAIT_TIMEOUT: + break; + default: + qErrnoWarning("QtLockedFile::lock(): WaitForSingleObject failed"); + } + return false; +} + + + +bool QtLockedFile::lock(LockMode mode, bool block) +{ + if (!isOpen()) { + qWarning("QtLockedFile::lock(): file is not opened"); + return false; + } + + if (mode == NoLock) + return unlock(); + + if (mode == m_lock_mode) + return true; + + if (m_lock_mode != NoLock) + unlock(); + + if (!wmutex && !(wmutex = getMutexHandle(-1, true))) + return false; + + if (!waitMutex(wmutex, block)) + return false; + + if (mode == ReadLock) { + int idx = 0; + for (; idx < MAX_READERS; idx++) { + rmutex = getMutexHandle(idx, false); + if (!rmutex || waitMutex(rmutex, false)) + break; + CloseHandle(rmutex); + } + bool ok = true; + if (idx >= MAX_READERS) { + qWarning("QtLockedFile::lock(): too many readers"); + rmutex = 0; + ok = false; + } + else if (!rmutex) { + rmutex = getMutexHandle(idx, true); + if (!rmutex || !waitMutex(rmutex, false)) + ok = false; + } + if (!ok && rmutex) { + CloseHandle(rmutex); + rmutex = 0; + } + ReleaseMutex(wmutex); + if (!ok) + return false; + } + else { + Q_ASSERT(rmutexes.isEmpty()); + for (int i = 0; i < MAX_READERS; i++) { + Qt::HANDLE mutex = getMutexHandle(i, false); + if (mutex) + rmutexes.append(mutex); + } + if (rmutexes.size()) { + DWORD res = WaitForMultipleObjects(rmutexes.size(), rmutexes.constData(), + TRUE, block ? INFINITE : 0); + if (res != WAIT_OBJECT_0 && res != WAIT_ABANDONED) { + if (res != WAIT_TIMEOUT) + qErrnoWarning("QtLockedFile::lock(): WaitForMultipleObjects failed"); + m_lock_mode = WriteLock; // trick unlock() to clean up - semiyucky + unlock(); + return false; + } + } + } + + m_lock_mode = mode; + return true; +} + +bool QtLockedFile::unlock() +{ + if (!isOpen()) { + qWarning("QtLockedFile::unlock(): file is not opened"); + return false; + } + + if (!isLocked()) + return true; + + if (m_lock_mode == ReadLock) { + ReleaseMutex(rmutex); + CloseHandle(rmutex); + rmutex = 0; + } + else { + foreach(Qt::HANDLE mutex, rmutexes) { + ReleaseMutex(mutex); + CloseHandle(mutex); + } + rmutexes.clear(); + ReleaseMutex(wmutex); + } + + m_lock_mode = QtLockedFile::NoLock; + return true; +} + +QtLockedFile::~QtLockedFile() +{ + if (isOpen()) + unlock(); + if (wmutex) + CloseHandle(wmutex); +} |