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39
40#ifndef QLOCKFILE_P_H
41#define QLOCKFILE_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists purely as an
48// implementation detail. This header file may change from version to
49// version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtCore/private/qglobal_p.h>
55#include <QtCore/qlockfile.h>
56#include <QtCore/qfile.h>
57
58#include <qplatformdefs.h>
59
60#ifdef Q_OS_WIN
61#include <io.h>
62#include <qt_windows.h>
63#endif
64
65QT_BEGIN_NAMESPACE
66
67class QLockFilePrivate
68{
69public:
70 QLockFilePrivate(const QString &fn)
71 : fileName(fn),
72#ifdef Q_OS_WIN
73 fileHandle(INVALID_HANDLE_VALUE),
74#else
75 fileHandle(-1),
76#endif
77 staleLockTime(30 * 1000), // 30 seconds
78 lockError(QLockFile::NoError),
79 isLocked(false)
80 {
81 }
82 QLockFile::LockError tryLock_sys();
83 bool removeStaleLock();
84 QByteArray lockFileContents() const;
85 // Returns \c true if the lock belongs to dead PID, or is old.
86 // The attempt to delete it will tell us if it was really stale or not, though.
87 bool isApparentlyStale() const;
88
89 // used in dbusmenu
90 Q_CORE_EXPORT static QString processNameByPid(qint64 pid);
91 static bool isProcessRunning(qint64 pid, const QString &appname);
92
93 QString fileName;
94#ifdef Q_OS_WIN
95 Qt::HANDLE fileHandle;
96#else
97 int fileHandle;
98#endif
99 int staleLockTime; // "int milliseconds" is big enough for 24 days
100 QLockFile::LockError lockError;
101 bool isLocked;
102
103 static int getLockFileHandle(QLockFile *f)
104 {
105 int fd;
106#ifdef Q_OS_WIN
107 // Use of this function on Windows WILL leak a file descriptor.
108 fd = _open_osfhandle(intptr_t(f->d_func()->fileHandle), 0);
109#else
110 fd = f->d_func()->fileHandle;
111#endif
112 QT_LSEEK(fd: fd, offset: 0, SEEK_SET);
113 return fd;
114 }
115};
116
117QT_END_NAMESPACE
118
119#endif /* QLOCKFILE_P_H */
120

source code of qtbase/src/corelib/io/qlockfile_p.h