summaryrefslogtreecommitdiff
path: root/src/singleinstance.h
blob: 9011d93af1ab5451fd00231adf748424e8d4998b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
/*
Copyright (C) 2012 Sebastian Herbord. All rights reserved.

This file is part of Mod Organizer.

Mod Organizer is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Mod Organizer is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Mod Organizer.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef SINGLEINSTANCE_H
#define SINGLEINSTANCE_H

#include <QLocalServer>
#include <QObject>
#include <QSharedMemory>

/**
 * used to ensure only a single instance of Mod Organizer is started and to
 * allow secondary instances to send messages to the primary (visible) one. This way,
 * secondary instances can start a download in the primary one
 **/
class SingleInstance : public QObject {

    Q_OBJECT

public:
    /**
     * @brief constructor
     *
     * @param forcePrimary if true, this will be treated as the primary instance even
     *                     if another instance is running. This is used after an update since
     *                     the other instance is assumed to be in the process of quitting
     * @param parent parent object
     * @todo the forcePrimary parameter makes no sense. The second instance after an update
     *       needs to delete the files from before the update so the first instance needs to quit
     *       first anyway
     **/
    explicit SingleInstance(bool forcePrimary, QObject* parent = 0);

    /**
     * @return true if this is the primary instance (the one that gets to display a UI)
     **/
    bool primaryInstance() const { return m_PrimaryInstance; }

    /**
     * send a message to the primary instance. This can be used to transmit download urls
     *
     * @param message message to send
     **/
    void sendMessage(const QString& message);

signals:

    /**
     * @brief emitted when a secondary instance has sent a message (to us)
     *
     * @param message the message we received
     **/
    void messageSent(const QString& message);

public slots:

private slots:

    void receiveMessage();

private:
    bool m_PrimaryInstance;
    QSharedMemory m_SharedMem;
    QLocalServer m_Server;
};

#endif // SINGLEINSTANCE_H