blob: 2f6587ce15717908622a8de6b76070453474b2ab (
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
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
/* $Id: EventQueue.h $ */
/** @file
* Event queue class declaration.
*/
/*
* Copyright (C) 2013 Oracle Corporation
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* you can redistribute it and/or modify it under the terms of the GNU
* General Public License (GPL) as published by the Free Software
* Foundation, in version 2 as it comes in the "COPYING" file of the
* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL) only, as it comes in the "COPYING.CDDL" file of the
* VirtualBox OSE distribution, in which case the provisions of the
* CDDL are applicable instead of those of the GPL.
*
* You may elect to license modified versions of this file under the
* terms and conditions of either the GPL or the CDDL or both.
*/
#ifndef ___VBox_com_EventQueue_h
#define ___VBox_com_EventQueue_h
#include <list>
#include <iprt/asm.h>
#include <iprt/critsect.h>
#include <VBox/com/defs.h>
#include <VBox/com/assert.h>
namespace com
{
class EventQueue;
/**
* Base class for all events. Intended to be subclassed to introduce new
* events and handlers for them.
*
* Subclasses usually reimplement virtual #handler() (that does nothing by
* default) and add new data members describing the event.
*/
class Event
{
public:
Event(void) :
mRefCount(0) { }
virtual ~Event(void) { AssertMsg(!mRefCount,
("Reference count of event=%p not 0 on destruction (is %RU32)\n",
this, mRefCount)); }
public:
uint32_t AddRef(void) { return ASMAtomicIncU32(&mRefCount); }
void Release(void)
{
Assert(mRefCount);
uint32_t cRefs = ASMAtomicDecU32(&mRefCount);
if (!cRefs)
delete this;
}
protected:
/**
* Event handler. Called in the context of the event queue's thread.
* Always reimplemented by subclasses
*
* @return reserved, should be NULL.
*/
virtual void *handler(void) { return NULL; }
friend class EventQueue;
protected:
/** The event's reference count. */
uint32_t mRefCount;
};
typedef std::list< Event* > EventQueueList;
typedef std::list< Event* >::iterator EventQueueListIterator;
typedef std::list< Event* >::const_iterator EventQueueListIteratorConst;
/**
* Simple event queue.
*/
class EventQueue
{
public:
EventQueue(void);
virtual ~EventQueue(void);
public:
BOOL postEvent(Event *event);
int processEventQueue(RTMSINTERVAL cMsTimeout);
int processPendingEvents(size_t cNumEvents);
int interruptEventQueueProcessing();
private:
/** Critical section for serializing access to this
* event queue. */
RTCRITSECT mCritSect;
/** Number of concurrent users. At the moment we
* only support one concurrent user at a time when
calling processEventQueue(). */
uint32_t mUserCnt;
/** Event semaphore for getting notified on new
* events being handled. */
RTSEMEVENT mSemEvent;
/** The actual event queue, implemented as a list. */
EventQueueList mEvents;
/** Shutdown indicator. */
bool mShutdown;
};
} /* namespace com */
#endif
|
