109 lines
2.9 KiB
C++
109 lines
2.9 KiB
C++
/****************************************************************************
|
|
**
|
|
** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
|
|
** Contact: http://www.qt-project.org/legal
|
|
**
|
|
** This file is part of Qt Creator.
|
|
**
|
|
** 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 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, 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.
|
|
**
|
|
****************************************************************************/
|
|
|
|
#include "qtlockedfile.h"
|
|
|
|
#include <cstring>
|
|
#include <cerrno>
|
|
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
|
|
namespace SharedTools {
|
|
|
|
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();
|
|
|
|
struct flock fl;
|
|
fl.l_whence = SEEK_SET;
|
|
fl.l_start = 0;
|
|
fl.l_len = 0;
|
|
fl.l_type = (mode == ReadLock) ? F_RDLCK : F_WRLCK;
|
|
int cmd = block ? F_SETLKW : F_SETLK;
|
|
int ret = fcntl(handle(), cmd, &fl);
|
|
|
|
if (ret == -1) {
|
|
if (errno != EINTR && errno != EAGAIN)
|
|
qWarning("QtLockedFile::lock(): fcntl: %s", strerror(errno));
|
|
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;
|
|
|
|
struct flock fl;
|
|
fl.l_whence = SEEK_SET;
|
|
fl.l_start = 0;
|
|
fl.l_len = 0;
|
|
fl.l_type = F_UNLCK;
|
|
int ret = fcntl(handle(), F_SETLKW, &fl);
|
|
|
|
if (ret == -1) {
|
|
qWarning("QtLockedFile::lock(): fcntl: %s", strerror(errno));
|
|
return false;
|
|
}
|
|
|
|
m_lock_mode = NoLock;
|
|
remove();
|
|
return true;
|
|
}
|
|
|
|
QtLockedFile::~QtLockedFile()
|
|
{
|
|
if (isOpen())
|
|
unlock();
|
|
}
|
|
|
|
} // namespace SharedTools
|