samples/thread/test.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        test.cpp
   3 // Purpose:     wxWindows thread sample
   4 // Author:      Julian Smart(minimal)/Guilhem Lavaux(thread test)
   5 // Modified by:
   6 // Created:     06/16/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart, Markus Holzem, Guilhem Lavaux
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 /*
  13     TODO: use worker threads to update progress controls instead of writing
  14           messages - it will be more visual
  15  */
  16
  17 #ifdef __GNUG__
  18     #pragma implementation "test.cpp"
  19     #pragma interface "test.cpp"
  20 #endif
  21
  22 // For compilers that support precompilation, includes "wx/wx.h".
  23 #include "wx/wxprec.h"
  24
  25 #ifdef __BORLANDC__
  26     #pragma hdrstop
  27 #endif
  28
  29 #ifndef WX_PRECOMP
  30     #include "wx/wx.h"
  31 #endif
  32
  33 #if !wxUSE_THREADS
  34     #error "This sample requires thread support!"
  35 #endif // wxUSE_THREADS
  36
  37 #include "wx/thread.h"
  38 #include "wx/dynarray.h"
  39 #include "wx/time.h"
  40
  41 class MyThread;
  42 WX_DEFINE_ARRAY(wxThread *, wxArrayThread);
  43
  44 // Define a new application type
  45 class MyApp : public wxApp
  46 {
  47 public:
  48     virtual bool OnInit();
  49
  50 public:
  51     // all the threads currently alive - as soon as the thread terminates, it's
  52     // removed from the array
  53     wxArrayThread m_threads;
  54
  55     // crit section protects access to all of the arrays below
  56     wxCriticalSection m_critsect;
  57 };
  58
  59 // Create a new application object
  60 IMPLEMENT_APP(MyApp)
  61
  62 // Define a new frame type
  63 class MyFrame: public wxFrame
  64 {
  65 public:
  66     // ctor
  67     MyFrame(wxFrame *frame, const wxString& title, int x, int y, int w, int h);
  68
  69     // operations
  70     void WriteText(const wxString& text) { m_txtctrl->WriteText(text); }
  71
  72     // callbacks
  73     void OnQuit(wxCommandEvent& event);
  74     void OnAbout(wxCommandEvent& event);
  75     void OnClear(wxCommandEvent& event);
  76
  77     void OnStartThread(wxCommandEvent& event);
  78     void OnStartThreads(wxCommandEvent& event);
  79     void OnStopThread(wxCommandEvent& event);
  80     void OnPauseThread(wxCommandEvent& event);
  81     void OnResumeThread(wxCommandEvent& event);
  82
  83     void OnStartWorker(wxCommandEvent& event);
  84     void OnWorkerEvent(wxCommandEvent& event);
  85
  86     void OnIdle(wxIdleEvent &event);
  87
  88 private:
  89     // helper function - creates a new thread (but doesn't run it)
  90     MyThread *CreateThread();
  91
  92     // just some place to put our messages in
  93     wxTextCtrl *m_txtctrl;
  94
  95     // remember the number of running threads and total number of threads
  96     size_t m_nRunning, m_nCount;
  97
  98     DECLARE_EVENT_TABLE()
  99 };
 100
 101 // ID for the menu commands
 102 enum
 103 {
 104     TEST_QUIT          = 1,
 105     TEST_TEXT          = 101,
 106     TEST_ABOUT,
 107     TEST_CLEAR,
 108     TEST_START_THREAD  = 201,
 109     TEST_START_THREADS,
 110     TEST_STOP_THREAD,
 111     TEST_PAUSE_THREAD,
 112     TEST_RESUME_THREAD,
 113     TEST_START_WORKER,
 114     WORKER_EVENT    // this one gets sent from the worker thread
 115 };
 116
 117 //--------------------------------------------------
 118 // GUI thread
 119 //--------------------------------------------------
 120
 121 class MyThread : public wxThread
 122 {
 123 public:
 124     MyThread(MyFrame *frame);
 125
 126     // thread execution starts here
 127     virtual void *Entry();
 128
 129     // called when the thread exits - whether it terminates normally or is
 130     // stopped with Delete() (but not when it is Kill()ed!)
 131     virtual void OnExit();
 132
 133     // write something to the text control
 134     void WriteText(const wxString& text);
 135
 136 public:
 137     size_t   m_count;
 138     MyFrame *m_frame;
 139 };
 140
 141 MyThread::MyThread(MyFrame *frame)
 142         : wxThread()
 143 {
 144     m_count = 0;
 145     m_frame = frame;
 146 }
 147
 148 void MyThread::WriteText(const wxString& text)
 149 {
 150     wxString msg;
 151
 152     // before doing any GUI calls we must ensure that this thread is the only
 153     // one doing it!
 154
 155     wxMutexGuiEnter();
 156
 157     msg << text;
 158     m_frame->WriteText(msg);
 159
 160     wxMutexGuiLeave();
 161 }
 162
 163 void MyThread::OnExit()
 164 {
 165     wxCriticalSectionLocker locker(wxGetApp().m_critsect);
 166
 167     wxGetApp().m_threads.Remove(this);
 168 }
 169
 170 void *MyThread::Entry()
 171 {
 172     wxString text;
 173
 174     text.Printf("Thread 0x%x started (priority = %d).\n",
 175                 GetId(), GetPriority());
 176     WriteText(text);
 177
 178     for ( m_count = 0; m_count < 10; m_count++ )
 179     {
 180         // check if we were asked to exit
 181         if ( TestDestroy() )
 182             break;
 183
 184         text.Printf("[%u] Thread 0x%x here.\n", m_count, GetId());
 185         WriteText(text);
 186
 187         // wxSleep() can't be called from non-GUI thread!
 188         wxThread::Sleep(1000);
 189     }
 190
 191     text.Printf("Thread 0x%x finished.\n", GetId());
 192     WriteText(text);
 193
 194     return NULL;
 195 }
 196
 197 //--------------------------------------------------
 198 // worker thread
 199 //--------------------------------------------------
 200
 201 class MyWorkerThread : public wxThread
 202 {
 203 public:
 204     MyWorkerThread(MyFrame *frame);
 205
 206     // thread execution starts here
 207     virtual void *Entry();
 208
 209     // called when the thread exits - whether it terminates normally or is
 210     // stopped with Delete() (but not when it is Kill()ed!)
 211     virtual void OnExit();
 212
 213 public:
 214     MyFrame *m_frame;
 215     size_t   m_count;
 216 };
 217
 218 MyWorkerThread::MyWorkerThread(MyFrame *frame)
 219         : wxThread()
 220 {
 221     m_frame = frame;
 222     m_count = 0;
 223 }
 224
 225 void MyWorkerThread::OnExit()
 226 {
 227 }
 228
 229 void *MyWorkerThread::Entry()
 230 {
 231     for ( m_count = 0; m_count < 10; m_count++ )
 232     {
 233         // check if we were asked to exit
 234         if ( TestDestroy() )
 235             break;
 236
 237         wxString text;
 238         text.Printf("[%u] Thread 0x%x here!!", m_count, GetId());
 239
 240         // create any type of command event here
 241         wxCommandEvent event( wxEVT_COMMAND_MENU_SELECTED, WORKER_EVENT );
 242         event.SetInt( WORKER_EVENT );
 243         event.SetString( text );
 244
 245         // send in a thread-safe way
 246         wxPostEvent( m_frame, event );
 247
 248         // same as:
 249         // m_frame->AddPendingEvent( event );
 250
 251         // wxSleep() can't be called from non-main thread!
 252         wxThread::Sleep(1000);
 253     }
 254
 255     return NULL;
 256 }
 257
 258 //--------------------------------------------------
 259 // main program
 260 //--------------------------------------------------
 261
 262 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 263     EVT_MENU(TEST_QUIT, MyFrame::OnQuit)
 264     EVT_MENU(TEST_ABOUT, MyFrame::OnAbout)
 265     EVT_MENU(TEST_CLEAR, MyFrame::OnClear)
 266     EVT_MENU(TEST_START_THREAD, MyFrame::OnStartThread)
 267     EVT_MENU(TEST_START_THREADS, MyFrame::OnStartThreads)
 268     EVT_MENU(TEST_STOP_THREAD, MyFrame::OnStopThread)
 269     EVT_MENU(TEST_PAUSE_THREAD, MyFrame::OnPauseThread)
 270     EVT_MENU(TEST_RESUME_THREAD, MyFrame::OnResumeThread)
 271
 272     EVT_MENU(TEST_START_WORKER, MyFrame::OnStartWorker)
 273     EVT_MENU(WORKER_EVENT, MyFrame::OnWorkerEvent)
 274
 275     EVT_IDLE(MyFrame::OnIdle)
 276 END_EVENT_TABLE()
 277
 278 // `Main program' equivalent, creating windows and returning main app frame
 279 bool MyApp::OnInit()
 280 {
 281     // Create the main frame window
 282     MyFrame *frame = new MyFrame((wxFrame *)NULL, "wxWindows threads sample",
 283                                  50, 50, 450, 340);
 284
 285     // Make a menubar
 286     wxMenu *file_menu = new wxMenu;
 287
 288     file_menu->Append(TEST_CLEAR, "&Clear log\tCtrl-L");
 289     file_menu->AppendSeparator();
 290     file_menu->Append(TEST_ABOUT, "&About");
 291     file_menu->AppendSeparator();
 292     file_menu->Append(TEST_QUIT, "E&xit\tAlt-X");
 293     wxMenuBar *menu_bar = new wxMenuBar;
 294     menu_bar->Append(file_menu, "&File");
 295
 296     wxMenu *thread_menu = new wxMenu;
 297     thread_menu->Append(TEST_START_THREAD, "&Start a new thread\tCtrl-N");
 298     thread_menu->Append(TEST_START_THREADS, "Start &many threads at once");
 299     thread_menu->Append(TEST_STOP_THREAD, "S&top a running thread\tCtrl-S");
 300     thread_menu->AppendSeparator();
 301     thread_menu->Append(TEST_PAUSE_THREAD, "&Pause a running thread\tCtrl-P");
 302     thread_menu->Append(TEST_RESUME_THREAD, "&Resume suspended thread\tCtrl-R");
 303     thread_menu->AppendSeparator();
 304     thread_menu->Append(TEST_START_WORKER, "Start &worker thread\tCtrl-W");
 305
 306     menu_bar->Append(thread_menu, "&Thread");
 307     frame->SetMenuBar(menu_bar);
 308
 309     // Show the frame
 310     frame->Show(TRUE);
 311
 312     SetTopWindow(frame);
 313
 314     return TRUE;
 315 }
 316
 317 // My frame constructor
 318 MyFrame::MyFrame(wxFrame *frame, const wxString& title,
 319                  int x, int y, int w, int h)
 320        : wxFrame(frame, -1, title, wxPoint(x, y), wxSize(w, h))
 321 {
 322     m_nRunning = m_nCount = 0;
 323
 324     CreateStatusBar(2);
 325
 326     m_txtctrl = new wxTextCtrl(this, -1, "", wxPoint(0, 0), wxSize(0, 0),
 327                                wxTE_MULTILINE | wxTE_READONLY);
 328
 329 }
 330
 331 MyThread *MyFrame::CreateThread()
 332 {
 333     MyThread *thread = new MyThread(this);
 334
 335     if ( thread->Create() != wxTHREAD_NO_ERROR )
 336     {
 337         wxLogError("Can't create thread!");
 338     }
 339
 340     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 341     wxGetApp().m_threads.Add(thread);
 342
 343     return thread;
 344 }
 345
 346 void MyFrame::OnStartThreads(wxCommandEvent& WXUNUSED(event) )
 347 {
 348     static long s_num = 10;
 349
 350     s_num = wxGetNumberFromUser("How many threads to start: ", "",
 351                                 "wxThread sample", s_num, 1, 10000, this);
 352     if ( s_num == -1 )
 353     {
 354         s_num = 10;
 355
 356         return;
 357     }
 358
 359     size_t count = (size_t)s_num, n;
 360
 361     wxArrayThread threads;
 362
 363     // first create them all...
 364     for ( n = 0; n < count; n++ )
 365     {
 366         wxThread *thr = CreateThread();
 367
 368         // we want to show the effect of SetPriority(): the first thread will
 369         // have the lowest priority, the second - the highest, all the rest
 370         // the normal one
 371         if ( n == 0 )
 372             thr->SetPriority(WXTHREAD_MIN_PRIORITY);
 373         else if ( n == 1 )
 374             thr->SetPriority(WXTHREAD_MAX_PRIORITY);
 375         else
 376             thr->SetPriority(WXTHREAD_DEFAULT_PRIORITY);
 377
 378         threads.Add(thr);
 379     }
 380
 381     wxString msg;
 382     msg.Printf("%d new threads created.", count);
 383     SetStatusText(msg, 1);
 384
 385     // ...and then start them
 386     for ( n = 0; n < count; n++ )
 387     {
 388         threads[n]->Run();
 389     }
 390 }
 391
 392 void MyFrame::OnStartThread(wxCommandEvent& WXUNUSED(event) )
 393 {
 394     MyThread *thread = CreateThread();
 395
 396     if ( thread->Run() != wxTHREAD_NO_ERROR )
 397     {
 398         wxLogError("Can't start thread!");
 399     }
 400
 401     SetStatusText("New thread started.", 1);
 402 }
 403
 404 void MyFrame::OnStopThread(wxCommandEvent& WXUNUSED(event) )
 405 {
 406     // stop the last thread
 407     if ( wxGetApp().m_threads.IsEmpty() )
 408     {
 409         wxLogError("No thread to stop!");
 410     }
 411     else
 412     {
 413         wxGetApp().m_critsect.Enter();
 414
 415         wxThread *thread = wxGetApp().m_threads.Last();
 416
 417         // it's important to leave critical section before calling Delete()
 418         // because delete will (implicitly) call OnExit() which also tries
 419         // to enter the same crit section - would dead lock.
 420         wxGetApp().m_critsect.Leave();
 421
 422         thread->Delete();
 423
 424         SetStatusText("Thread stopped.", 1);
 425     }
 426 }
 427
 428 void MyFrame::OnResumeThread(wxCommandEvent& WXUNUSED(event) )
 429 {
 430     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 431
 432     // resume first suspended thread
 433     size_t n = 0, count = wxGetApp().m_threads.Count();
 434     while ( n < count && !wxGetApp().m_threads[n]->IsPaused() )
 435         n++;
 436
 437     if ( n == count )
 438     {
 439         wxLogError("No thread to resume!");
 440     }
 441     else
 442     {
 443         wxGetApp().m_threads[n]->Resume();
 444
 445         SetStatusText("Thread resumed.", 1);
 446     }
 447 }
 448
 449 void MyFrame::OnPauseThread(wxCommandEvent& WXUNUSED(event) )
 450 {
 451     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 452
 453     // pause last running thread
 454     int n = wxGetApp().m_threads.Count() - 1;
 455     while ( n >= 0 && !wxGetApp().m_threads[n]->IsRunning() )
 456         n--;
 457
 458     if ( n < 0 )
 459     {
 460         wxLogError("No thread to pause!");
 461     }
 462     else
 463     {
 464         wxGetApp().m_threads[n]->Pause();
 465
 466         SetStatusText("Thread paused.", 1);
 467     }
 468 }
 469
 470 // set the frame title indicating the current number of threads
 471 void MyFrame::OnIdle(wxIdleEvent &event)
 472 {
 473     // update the counts of running/total threads
 474     size_t nRunning = 0,
 475            nCount = wxGetApp().m_threads.Count();
 476     for ( size_t n = 0; n < nCount; n++ )
 477     {
 478         if ( wxGetApp().m_threads[n]->IsRunning() )
 479             nRunning++;
 480     }
 481
 482     if ( nCount != m_nCount || nRunning != m_nRunning )
 483     {
 484         m_nRunning = nRunning;
 485         m_nCount = nCount;
 486
 487         wxLogStatus(this, "%u threads total, %u running.", nCount, nRunning);
 488     }
 489     //else: avoid flicker - don't print anything
 490 }
 491
 492 void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event) )
 493 {
 494     size_t count = wxGetApp().m_threads.Count();
 495     for ( size_t i = 0; i < count; i++ )
 496     {
 497         wxGetApp().m_threads[0]->Delete();
 498     }
 499
 500     Close(TRUE);
 501 }
 502
 503 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event) )
 504 {
 505     wxMessageDialog dialog(this, "wxWindows multithreaded application sample\n"
 506                                  "(c) 1998 Julian Smart, Guilhem Lavaux\n"
 507                                  "(c) 1999 Vadim Zeitlin\n"
 508                                  "(c) 2000 Robert Roebling",
 509                            "About wxThread sample",
 510                            wxOK | wxICON_INFORMATION);
 511
 512     dialog.ShowModal();
 513 }
 514
 515 void MyFrame::OnClear(wxCommandEvent& WXUNUSED(event))
 516 {
 517     m_txtctrl->Clear();
 518 }
 519
 520 void MyFrame::OnStartWorker(wxCommandEvent& WXUNUSED(event))
 521 {
 522     MyWorkerThread *thread = new MyWorkerThread(this);
 523
 524     if ( thread->Create() != wxTHREAD_NO_ERROR )
 525     {
 526         wxLogError("Can't create thread!");
 527     }
 528
 529     thread->Run();
 530 }
 531
 532 void MyFrame::OnWorkerEvent(wxCommandEvent& event)
 533 {
 534     WriteText( "Got message from worker thread: " );
 535     WriteText( event.GetString() );
 536     WriteText( "\n" );
 537 }
 538