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diff --git a/src/shared/qtlockedfile/qtlockedfile.cpp b/src/shared/qtlockedfile/qtlockedfile.cpp
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+++ b/src/shared/qtlockedfile/qtlockedfile.cpp
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+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include "qtlockedfile.h"
+
+namespace SharedTools {
+
+/*!
+    \class QtLockedFile
+
+    \brief The QtLockedFile class extends QFile with advisory locking functions.
+
+    A file may be locked in read or write mode. Multiple instances of
+    \e QtLockedFile, created in multiple processes running on the same
+    machine, may have a file locked in read mode. Exactly one instance
+    may have it locked in write mode. A read and a write lock cannot
+    exist simultaneously on the same file.
+
+    The file locks are advisory. This means that nothing prevents
+    another process from manipulating a locked file using QFile or
+    file system functions offered by the OS. Serialization is only
+    guaranteed if all processes that access the file use
+    QtLockedFile. Also, while holding a lock on a file, a process
+    must not open the same file again (through any API), or locks
+    can be unexpectedly lost.
+
+    The lock provided by an instance of \e QtLockedFile is released
+    whenever the program terminates. This is true even when the
+    program crashes and no destructors are called.
+*/
+
+/*! \enum QtLockedFile::LockMode
+
+    This enum describes the available lock modes.
+
+    \value ReadLock A read lock.
+    \value WriteLock A write lock.
+    \value NoLock Neither a read lock nor a write lock.
+*/
+
+/*!
+    Constructs an unlocked \e QtLockedFile object. This constructor behaves in the same way
+    as \e QFile::QFile().
+
+    \sa QFile::QFile()
+*/
+QtLockedFile::QtLockedFile()
+    : QFile()
+{
+#ifdef Q_OS_WIN
+    m_semaphore_hnd = 0;
+    m_mutex_hnd = 0;
+#endif
+    m_lock_mode = NoLock;
+}
+
+/*!
+    Constructs an unlocked QtLockedFile object with file \a name. This constructor behaves in
+    the same way as \e QFile::QFile(const QString&).
+
+    \sa QFile::QFile()
+*/
+QtLockedFile::QtLockedFile(const QString &name)
+    : QFile(name)
+{
+#ifdef Q_OS_WIN
+    m_semaphore_hnd = 0;
+    m_mutex_hnd = 0;
+#endif
+    m_lock_mode = NoLock;
+}
+
+/*!
+    Returns \e true if this object has a in read or write lock;
+    otherwise returns \e false.
+
+    \sa lockMode()
+*/
+bool QtLockedFile::isLocked() const
+{
+    return m_lock_mode != NoLock;
+}
+
+/*!
+    Returns the type of lock currently held by this object, or \e QtLockedFile::NoLock.
+
+    \sa isLocked()
+*/
+QtLockedFile::LockMode QtLockedFile::lockMode() const
+{
+    return m_lock_mode;
+}
+
+/*!
+    \fn bool QtLockedFile::lock(LockMode mode, bool block = true)
+
+    Obtains a lock of type \a mode.
+
+    If \a block is true, this
+    function will block until the lock is acquired. If \a block is
+    false, this function returns \e false immediately if the lock cannot
+    be acquired.
+
+    If this object already has a lock of type \a mode, this function returns \e true immediately. If this object has a lock of a different type than \a mode, the lock
+    is first released and then a new lock is obtained.
+
+    This function returns \e true if, after it executes, the file is locked by this object,
+    and \e false otherwise.
+
+    \sa unlock(), isLocked(), lockMode()
+*/
+
+/*!
+    \fn bool QtLockedFile::unlock()
+
+    Releases a lock.
+
+    If the object has no lock, this function returns immediately.
+
+    This function returns \e true if, after it executes, the file is not locked by
+    this object, and \e false otherwise.
+
+    \sa lock(), isLocked(), lockMode()
+*/
+
+/*!
+    \fn QtLockedFile::~QtLockedFile()
+
+    Destroys the \e QtLockedFile object. If any locks were held, they are released.
+*/
+
+} // namespace SharedTools