btrfs: Attempt to fix GCC2 build.
[haiku.git] / src / apps / cortex / support / ObservableLooper.h
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1 /*
2 * Copyright (c) 1999-2000, Eric Moon.
3 * All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions, and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions, and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * 3. The name of the author may not be used to endorse or promote products
17 * derived from this software without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF TITLE, NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
23 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
27 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 // ObservableLooper.h
33 // * PURPOSE
34 // Implementation of an observable (target) derived
35 // from BLooper.
37 // * HISTORY
38 // e.moon 18aug99 Begun
40 #ifndef __ObservableLooper_H__
41 #define __ObservableLooper_H__
43 #include <Looper.h>
44 class BMessageRunner;
46 #include "observe.h"
47 #include "IObservable.h"
48 #include "MultiInvoker.h"
50 #include "cortex_defs.h"
51 __BEGIN_CORTEX_NAMESPACE
53 class ObservableLooper :
54 public BLooper,
55 public IObservable,
56 private MultiInvoker {
58 typedef BLooper _inherited;
60 public: // *** deletion
61 // clients must call release() rather than deleting,
62 // to ensure that all observers are notified of the
63 // object's demise. if the object has already been
64 // released, return an error.
66 virtual status_t release();
68 public: // *** ctor/dtor
69 virtual ~ObservableLooper();
70 ObservableLooper(
71 const char* name=0,
72 int32 priority=B_NORMAL_PRIORITY,
73 int32 portCapacity=B_LOOPER_PORT_DEFAULT_CAPACITY,
74 bigtime_t quitTimeout=B_INFINITE_TIMEOUT);
75 ObservableLooper(
76 BMessage* archive);
78 public: // *** accessors
79 // return true if release() has been called, false otherwise.
80 bool isReleased() const;
82 protected: // *** hooks
83 // sends M_OBSERVER_ADDED to the newly-added observer
84 virtual void observerAdded(
85 const BMessenger& observer);
87 // sends M_OBSERVER_REMOVED to the newly-removed observer
88 virtual void observerRemoved(
89 const BMessenger& observer);
91 protected: // *** internal operations
92 // call to send the given message to all observers.
93 // Responsibility for deletion of the message remains with
94 // the caller.
95 // * LOCKING: the BLooper must be locked.
96 virtual status_t notify(
97 BMessage* message);
99 // sends M_RELEASE_OBSERVABLE
100 virtual void notifyRelease();
102 public: // *** BLooper
103 virtual void Quit();
104 virtual bool QuitRequested();
106 public: // *** BHandler
107 virtual void MessageReceived(
108 BMessage* message);
110 public: // *** BArchivable
111 // * LOCKING: the BLooper must be locked.
112 virtual status_t Archive(
113 BMessage* archive,
114 bool deep=true) const;
116 private: // implementation
117 void _handleAddObserver(
118 BMessage* message);
120 void _handleRemoveObserver(
121 BMessage* message);
123 private: // members
124 // how long to wait after being requested to shut down
125 // before giving up on stuck observers
126 bigtime_t m_quitTimeout;
127 BMessageRunner* m_executioner;
129 // true if a quit has been requested
130 bool m_quitting;
133 __END_CORTEX_NAMESPACE
134 #endif /*__ObservableLooper_H__*/