1 /*
2  * Copyright (C) 2006-2008 Marc Boris Duerner
3  *
4  * This library is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * As a special exception, you may use this file as part of a free
10  * software library without restriction. Specifically, if other files
11  * instantiate templates or use macros or inline functions from this
12  * file, or you compile this file and link it with other files to
13  * produce an executable, this file does not by itself cause the
14  * resulting executable to be covered by the GNU General Public
15  * License. This exception does not however invalidate any other
16  * reasons why the executable file might be covered by the GNU Library
17  * General Public License.
18  *
19  * This library is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
22  * Lesser General Public License for more details.
23  *
24  * You should have received a copy of the GNU Lesser General Public
25  * License along with this library; if not, write to the Free Software
26  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
27  */
28 #ifndef CXXTOOLS_APPLICATION_H
29 #define CXXTOOLS_APPLICATION_H
30 
31 #include <cxxtools/api.h>
32 #include <cxxtools/eventloop.h>
33 #include <cxxtools/application.h>
34 #include <cxxtools/connectable.h>
35 #include <cxxtools/event.h>
36 #include <cxxtools/signal.h>
37 
38 namespace cxxtools {
39 
40     class ApplicationImpl;
41 
42     /**
43      * \brief The Application class provides an event loop for console applications
44      * without a GUI.
45      *
46      * This class is used by non-GUI applications to provide the applications's event
47      * loop. There should be only exactly one instance of Application (or one of its
48      * subclasses) per application. This is not ensured, though.
49      *
50      * Application contains the main event loop, where event sources can be registered
51      * and events from those sources are dispatched to listeners, that were registered
52      * to the event loop. Events may for example be operating system events (timer, file
53      * system changes).
54      *
55      * The application and therefore the event loop is started with a call to run() and
56      * can be exited with a call to exit(). After calling exit() the application should
57      * terminate.
58      *
59      * The event loop can be access by calling eventLoop(). Events can be committed by
60      * calling EventLoop::commitEvent(). Long running operations can call
61      * EventLoop::processEvents() to keep the application responsive.
62      *
63      * There are convenience methods available for easier access to functionality of
64      * the underlying event loop. commitEvent() delegates to EventLoop::commitEvent(),
65      * queueEvent() delegates to EventLoop::delegateEvent() and processEvents() delegates
66      * to EventLoop::processEvents() without making it necessary to first obtain the
67      * event loop manually.
68      */
69     class CXXTOOLS_API Application : public Connectable
70     {
71             void construct();
72 
73         public:
74             Application();
75 
76             Application(int argc, char** argv);
77 
78             Application(EventLoopBase* loop);
79 
80             Application(EventLoopBase* loop, int argc, char** argv);
81 
82             ~Application();
83 
84             static Application& instance();
85 
loop()86             EventLoopBase& loop()
87             { return *_loop; }
88 
run()89             void run()
90             { _loop->run(); }
91 
exit()92             void exit()
93             { _loop->exit(); }
94 
95             bool catchSystemSignal(int sig);
96 
97             bool raiseSystemSignal(int sig);
98 
99             Signal<int> systemSignal;
100 
argc()101             int argc() const
102             { return _argc; }
103 
argv()104             char** argv() const
105             { return _argv; }
106 
impl()107             ApplicationImpl& impl()
108             { return *_impl; }
109 
110         protected:
111             void init(EventLoopBase& loop);
112 
113         private:
114             ApplicationImpl* _impl;
115             int     _argc;
116             char**  _argv;
117             EventLoopBase* _loop;
118             EventLoop* _owner;
119     };
120 
121 } // namespace cxxtools
122 
123 #endif
124