diff options
Diffstat (limited to 'src/libs/kdtools/lockfile_unix.cpp')
-rw-r--r-- | src/libs/kdtools/lockfile_unix.cpp | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/src/libs/kdtools/lockfile_unix.cpp b/src/libs/kdtools/lockfile_unix.cpp new file mode 100644 index 000000000..bb978c40f --- /dev/null +++ b/src/libs/kdtools/lockfile_unix.cpp @@ -0,0 +1,93 @@ +/**************************************************************************** +** +** Copyright (C) 2013 Klaralvdalens Datakonsult AB (KDAB) +** Copyright (C) 2017 The Qt Company Ltd. +** Contact: https://www.qt.io/licensing/ +** +** This file is part of the Qt Installer Framework. +** +** $QT_BEGIN_LICENSE:GPL-EXCEPT$ +** 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 The Qt Company. For licensing terms +** and conditions see https://www.qt.io/terms-conditions. For further +** information use the contact form at https://www.qt.io/contact-us. +** +** GNU General Public License Usage +** Alternatively, this file may be used under the terms of the GNU +** General Public License version 3 as published by the Free Software +** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT +** included in the packaging of this file. Please review the following +** information to ensure the GNU General Public License requirements will +** be met: https://www.gnu.org/licenses/gpl-3.0.html. +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "lockfile_p.h" + +#include <QCoreApplication> +#include <QDir> + +#include <cerrno> +#include <sys/file.h> +#include <unistd.h> + +namespace KDUpdater { + +bool LockFile::Private::lock() +{ + if (locked) + return true; + + errorString.clear(); + errno = 0; + handle = open(filename.toLatin1().constData(), O_CREAT | O_RDWR | O_NONBLOCK, 0600); + if (handle == -1) { + errorString = QCoreApplication::translate("LockFile", "Cannot create lock file \"%1\": " + "%2").arg(QDir::toNativeSeparators(filename), QString::fromLocal8Bit(strerror(errno))); + return false; + } + const QString pid = QString::number(qApp->applicationPid()); + const QByteArray data = pid.toLatin1(); + errno = 0; + qint64 written = 0; + while (written < data.size()) { + const qint64 n = write(handle, data.constData() + written, data.size() - written); + if (n < 0) { + errorString = QCoreApplication::translate("LockFile", "Cannot write PID to lock " + "file \"%1\": %2").arg(QDir::toNativeSeparators(filename), QString::fromLocal8Bit(strerror(errno))); + return false; + } + written += n; + } + errno = 0; + locked = flock(handle, LOCK_NB | LOCK_EX) != -1; + if (!locked) { + errorString = QCoreApplication::translate("LockFile", "Cannot obtain the lock for " + "file \"%1\": %2").arg(QDir::toNativeSeparators(filename), QString::fromLocal8Bit(strerror(errno))); + } + return locked; +} + +bool LockFile::Private::unlock() +{ + errorString.clear(); + if (!locked) + return true; + + errno = 0; + locked = flock(handle, LOCK_UN | LOCK_NB) == -1; + if (locked) { + errorString = QCoreApplication::translate("LockFile", "Cannot release the lock for " + "file \"%1\": %2").arg(QDir::toNativeSeparators(filename), QString::fromLocal8Bit(strerror(errno))); + } else { + unlink(filename.toLatin1()); + } + return !locked; +} + +} // namespace KDUpdater |