OpenFlipperThread.hh 11.2 KB
Newer Older
Jan Möbius's avatar
Jan Möbius committed
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
/*===========================================================================*\
*                                                                            *
*                              OpenFlipper                                   *
*      Copyright (C) 2001-2010 by Computer Graphics Group, RWTH Aachen       *
*                           www.openflipper.org                              *
*                                                                            *
*--------------------------------------------------------------------------- *
*  This file is part of OpenFlipper.                                         *
*                                                                            *
*  OpenFlipper is free software: you can redistribute it and/or modify       *
*  it under the terms of the GNU Lesser General Public License as            *
*  published by the Free Software Foundation, either version 3 of            *
*  the License, or (at your option) any later version with the               *
*  following exceptions:                                                     *
*                                                                            *
*  If other files instantiate templates or use macros                        *
*  or inline functions from this file, or you compile this file and          *
*  link it with other files to produce an executable, this file does         *
*  not by itself cause the resulting executable to be covered by the         *
*  GNU Lesser General Public License. This exception does not however        *
*  invalidate any other reasons why the executable file might be             *
*  covered by the GNU Lesser General Public License.                         *
*                                                                            *
*  OpenFlipper 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 Lesser General Public License for more details.                       *
*                                                                            *
*  You should have received a copy of the GNU LesserGeneral Public           *
*  License along with OpenFlipper. If not,                                   *
*  see <http://www.gnu.org/licenses/>.                                       *
*                                                                            *
\*===========================================================================*/

/*===========================================================================*\
*                                                                            *
*   $Revision$                                                       *
*   $LastChangedBy$                                                *
*   $Date$                     *
*                                                                            *
\*===========================================================================*/
42
43
44
45
46
47


#ifndef OPENFLIPPERTHREAD_HH
#define OPENFLIPPERTHREAD_HH

#include <QThread>
48
#include <QSemaphore>
49
50
51

#include <OpenFlipper/common/GlobalDefines.hh>

52
53
54
55
56
57
58
59
/**
\class OpenFlipperThread

    Instanciate this class in order to provide a thread
    to a plugin. Unless you don't need a specialized
    run() or cancel() function, it won't be necessary to
    reimplement this class. Just connect the signals
    for the thread to work properly.
Mike Kremer's avatar
Mike Kremer committed
60
61
62
63
64
65
66
67
        
    Note: Updating GUI elements of the main window from
    within a thread which is not the main thread can
    cause unexpected crashes to OpenFlipper. This introduces
    some major limitations to the usage of threads
    in plugins. These include avoiding the creation
    of new objects and generally every function that
    produces logging messages.
68

Mike Kremer's avatar
Mike Kremer committed
69
    The following code fragment shows a simple example
70
71
72
    of how to use this class from within a plugin:

\code
Mike Kremer's avatar
Mike Kremer committed
73
void MyPlugin::launchThread() {
74

Mike Kremer's avatar
Mike Kremer committed
75
    OpenFlipperThread* myThread = new OpenFlipperThread("MyPluginsThread");
76

Mike Kremer's avatar
Mike Kremer committed
77
78
    // Connect the appropriate signals
    connect(myThread, SIGNAL(function()), this, SLOT(myPluginsThreadFunction()), Qt::DirectConnection);
79

Mike Kremer's avatar
Mike Kremer committed
80
81
82
    // Tell core about my thread
    // Note: The last parameter determines whether the thread should be blocking
    emit startJob( "MyPluginsThread", "Thread Description" , 0 , 100 , true);
83

Mike Kremer's avatar
Mike Kremer committed
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
    // Start internal QThread
    myThread->start();

    // Start actual processing of job
    myThread->startProcessing();

}

void MyPlugin::myPluginsThreadFunction() {
   
   emit setJobState("MyPluginsThread", 0);
   
   // Do something...
   for(int i = 0; i < 100; ++i) {
   
       // Do something...
       
       // Update process' progress bar status
       emit setJobState("MyPluginsThread", i);
   }
   
   emit finishJob("MyPluginsThread");
}
107
108
109
\endcode
*/

Jan Möbius's avatar
Jan Möbius committed
110
111
class OpenFlipperJob;

112
113
114
115
116
117
118
119
class DLLEXPORT OpenFlipperThread : public QThread
{
  Q_OBJECT
  
  public:
    OpenFlipperThread( QString _jobId );
    ~OpenFlipperThread();
    
Jan Möbius's avatar
Jan Möbius committed
120
121
122
123
124
125
  //===========================================================================
  /** @name Advanced job processing
  * @{ */
  //===========================================================================
  public:
    
126
127
    /** \brief Main processing
    *
128
129
    * Either reimplement this function or connect the function()
    * signal.
130
131
132
    */
    virtual void run();
    
Jan Möbius's avatar
Jan Möbius committed
133
134
135
136
137
138
139
    /** \brief Cancel the job
    *
    * Reimplement this function to correctly terminate your job.
    * If your job is able to terminate correctly then you can reimplement this function
    * and stop your process.
    */
    virtual void cancel();   
140
141
142
143
144
145
146
147
148
    
  public slots:
    /** Call this slot with the correct job id to abort processing
    * This directly calls cancel()
    * This is only usefull when you derived from this class, as other jobs might not react on this slot
    */
    void slotCancel( QString _jobId);
    
  signals:
Jan Möbius's avatar
Jan Möbius committed
149
150
151
152
153
    /** \brief Tell core about job state
    *
    * Emit this signal to tell the core about your job status. You have to create a new run function for
    * this. In simple mode, this signal is not emitted at all!
    */
154
155
    void state( QString _jobId, int _state );
    
Jan Möbius's avatar
Jan Möbius committed
156
  /** @} */
157
    
Jan Möbius's avatar
Jan Möbius committed
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
    
  //===========================================================================
  /** @name Simple job processing
  * @{ */
  //===========================================================================
    
  signals:
    /**  \brief job function
    *
    * If you do not specialize the OpenFlipperThread, The function connected to this 
    * signal will be used as the processing function for your thread. When you call
    * OpenFlipper::startProcessing(); \n
    *
    * If you want to provide more feedback (% of runtime) or cancel the job,
    * you have to derive from OpenFlipperThread and emit the right signals.
    * 
    * You have connect one of your slot using \n
175
176
    * connect( OpenFlipperThread ,SIGNAL(function()),YourPlugin,SLOT(YourSlot(),Qt::DirectConnection) );\n
    * The default implementation will call your slot inside the given thread and the core will still respond.
Jan Möbius's avatar
Jan Möbius committed
177
178
179
    * However you should only use this function if you Dont know how long your job takes. Or when
    * you just want to keep the core responding.\n
    * Otherwise you should reimplement the run(), and cancel() function of OpenFlipperThread and emit the state signal.
180
181
182
    *
    * The optional parameter contains the job's id. In some cases the function that is to be called needs
    * the job's id for further processing (status updates, etc.)
183
    */
184
    void function(const QString _jobId = "");
Jan Möbius's avatar
Jan Möbius committed
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
    
    /** \brief job done
    *
    * This signal is emitted if your job has finished and should be used to tell the core that your job has finished.
    *
    */
    void finished( QString _jobId );
    
    
    
  public slots:
    /** \brief start processing
    *
    * This function will start the actuall processing of a job.
    */
    void startProcessing();
    
  /** @} */
    
    
  private slots:
    /** \brief job has finished
    * 
    * Called by the job wrapper, when the job is done.
    */
    void slotJobFinished();
  
  signals:
    /** \brief start processing of a function
    *
    * (INTERNAL!) \n
    * This signal is used to start the process execution through the wrapper
    */
    void startProcessingInternal();
    
  private: 
    /** \brief Internal job wrapper
    *
    * (INTERNAL!) \n
    * This wrapper is used to start slots inside the event queue of the current thread.
    * All slots defined in the QThread object live in the callers thread(The main thread).
    * All slots inside the wrapper live in the thread created by QThread. and therefore
    * do not lock the main event loop
    */
    OpenFlipperJob* job_;
    
    /** \brief Id of the current job
    *
    * This holds the id of the current job. Most functions only react if the correct id is passed
    * to the function.
    */
    QString jobId_;
    
238
239
240
241
242
243
244
245
246
    /** \brief Semaphore to control order of thread startup calls
    *
    * This variable is used to control the order of thread startup calls. The Thread itself is
    * started, and when it is up and running, the resource will be created. The core thread waits
    * for this resource and afterwards starts execution of the threads processing function.
    * Without this sync, the processing call of the main thread might get lost as the thread is
    * not online and listening for the signal.
    */
    QSemaphore startup_;
Jan Möbius's avatar
Jan Möbius committed
247
248
249

};

250

Jan Möbius's avatar
Jan Möbius committed
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
// ================================================================================
// Job wrapper
// ================================================================================

/** \brief Internal Job execution object
*
* This class is used to start a process within a thread. The thread object itself
* lives in the event queue of the object that crreated the thread. So every signal
* or slot within the qthread object will be dispatched in the core event loop and
* therefore lock the gui. 
* Objects created in the qthread will run in the threads event queue as well as their
* signals and slots. So qthread uses this object to actually run arbitrary threads 
* inside the threads event queue.
*/
class DLLEXPORT OpenFlipperJob : public QObject
{
  Q_OBJECT
  
  public:
270
    OpenFlipperJob(const QString _jobId) : jobId_(_jobId) {}
Jan Möbius's avatar
Jan Möbius committed
271
    ~OpenFlipperJob();
Jan Möbius's avatar
Jan Möbius committed
272
273
274
275
276
277
278
279
280
  
  signals:
    /** \brief connection to actual processing function
    *
    * This signal has to be connected via a Qt::DirectConnection to an
    * arbitrary slot. This slot will be executed in the local event queue.
    * If this object is created in a QThread, than the slot will be run 
    * inside this thread.
    */
281
    void process(const QString _jobId = "");
Jan Möbius's avatar
Jan Möbius committed
282
283
284
285
286
287
288
289
290
291
292
293
294
295
    
    /** \brief Job done
    *
    * This signal is emitted, when the job has finished
    */
    void finished();
    
  public slots:
    /** \brief slot to start processing
    *
    * If this slot is called, the slot connected to process() will be executed
    * in the current thread.
    */
    void startJobProcessing();
296
    
297
298
299
300
301
302
303
304
305
306
  public:
    /// Set job's id
    void jobId(const QString& _jobId) { jobId_ = _jobId; }
    
    /// Get job's id
    QString jobId() const { return jobId_; }   
    
  private:
    /// The job's id
    QString jobId_;
307
308
309
310
311
};



#endif //OPENFLIPPERTHREAD_HH