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
 159     m_frame->WriteText(msg);
 160
 161     wxMutexGuiLeave();
 162 }
 163
 164 void MyThread::OnExit()
 165 {
 166     wxCriticalSectionLocker locker(wxGetApp().m_critsect);
 167
 168     wxGetApp().m_threads.Remove(this);
 169 }
 170
 171 void *MyThread::Entry()
 172 {
 173     wxString text;
 174
 175     text.Printf("Thread 0x%x started (priority = %d).\n",
 176                 GetId(), GetPriority());
 177     WriteText(text);
 178
 179     for ( m_count = 0; m_count < 10; m_count++ )
 180     {
 181         // check if we were asked to exit
 182         if ( TestDestroy() )
 183             break;
 184
 185         text.Printf("[%u] Thread 0x%x here.\n", m_count, GetId());
 186         WriteText(text);
 187
 188         // wxSleep() can't be called from non-GUI thread!
 189         wxThread::Sleep(1000);
 190     }
 191
 192     text.Printf("Thread 0x%x finished.\n", GetId());
 193     WriteText(text);
 194
 195     return NULL;
 196 }
 197
 198 //--------------------------------------------------
 199 // worker thread
 200 //--------------------------------------------------
 201
 202 class MyWorkerThread : public wxThread
 203 {
 204 public:
 205     MyWorkerThread(MyFrame *frame);
 206
 207     // thread execution starts here
 208     virtual void *Entry();
 209
 210     // called when the thread exits - whether it terminates normally or is
 211     // stopped with Delete() (but not when it is Kill()ed!)
 212     virtual void OnExit();
 213
 214 public:
 215     MyFrame *m_frame;
 216     size_t   m_count;
 217 };
 218
 219 MyWorkerThread::MyWorkerThread(MyFrame *frame)
 220         : wxThread()
 221 {
 222     m_frame = frame;
 223     m_count = 0;
 224 }
 225
 226 void MyWorkerThread::OnExit()
 227 {
 228 }
 229
 230 void *MyWorkerThread::Entry()
 231 {
 232     for ( m_count = 0; m_count < 10; m_count++ )
 233     {
 234         // check if we were asked to exit
 235         if ( TestDestroy() )
 236             break;
 237
 238         wxCommandEvent event( wxEVT_COMMAND_MENU_SELECTED, WORKER_EVENT );
 239         event.SetInt( WORKER_EVENT );
 240         wxPostEvent( m_frame, event );
 241
 242         // wxSleep() can't be called from non-GUI thread!
 243         wxThread::Sleep(1000);
 244     }
 245
 246     return NULL;
 247 }
 248
 249 //--------------------------------------------------
 250 // main program
 251 //--------------------------------------------------
 252
 253 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 254     EVT_MENU(TEST_QUIT, MyFrame::OnQuit)
 255     EVT_MENU(TEST_ABOUT, MyFrame::OnAbout)
 256     EVT_MENU(TEST_CLEAR, MyFrame::OnClear)
 257     EVT_MENU(TEST_START_THREAD, MyFrame::OnStartThread)
 258     EVT_MENU(TEST_START_THREADS, MyFrame::OnStartThreads)
 259     EVT_MENU(TEST_STOP_THREAD, MyFrame::OnStopThread)
 260     EVT_MENU(TEST_PAUSE_THREAD, MyFrame::OnPauseThread)
 261     EVT_MENU(TEST_RESUME_THREAD, MyFrame::OnResumeThread)
 262
 263     EVT_MENU(TEST_START_WORKER, MyFrame::OnStartWorker)
 264     EVT_MENU(WORKER_EVENT, MyFrame::OnWorkerEvent)
 265
 266     EVT_IDLE(MyFrame::OnIdle)
 267 END_EVENT_TABLE()
 268
 269 // `Main program' equivalent, creating windows and returning main app frame
 270 bool MyApp::OnInit()
 271 {
 272     // Create the main frame window
 273     MyFrame *frame = new MyFrame((wxFrame *)NULL, "wxWindows threads sample",
 274                                  50, 50, 450, 340);
 275
 276     // Make a menubar
 277     wxMenu *file_menu = new wxMenu;
 278
 279     file_menu->Append(TEST_CLEAR, "&Clear log\tCtrl-L");
 280     file_menu->AppendSeparator();
 281     file_menu->Append(TEST_ABOUT, "&About");
 282     file_menu->AppendSeparator();
 283     file_menu->Append(TEST_QUIT, "E&xit\tAlt-X");
 284     wxMenuBar *menu_bar = new wxMenuBar;
 285     menu_bar->Append(file_menu, "&File");
 286
 287     wxMenu *thread_menu = new wxMenu;
 288     thread_menu->Append(TEST_START_THREAD, "&Start a new thread\tCtrl-N");
 289     thread_menu->Append(TEST_START_THREADS, "Start &many threads at once");
 290     thread_menu->Append(TEST_STOP_THREAD, "S&top a running thread\tCtrl-S");
 291     thread_menu->AppendSeparator();
 292     thread_menu->Append(TEST_PAUSE_THREAD, "&Pause a running thread\tCtrl-P");
 293     thread_menu->Append(TEST_RESUME_THREAD, "&Resume suspended thread\tCtrl-R");
 294     thread_menu->AppendSeparator();
 295     thread_menu->Append(TEST_START_WORKER, "Start &worker thread\tCtrl-W");
 296
 297     menu_bar->Append(thread_menu, "&Thread");
 298     frame->SetMenuBar(menu_bar);
 299
 300     // Show the frame
 301     frame->Show(TRUE);
 302
 303     SetTopWindow(frame);
 304
 305     return TRUE;
 306 }
 307
 308 // My frame constructor
 309 MyFrame::MyFrame(wxFrame *frame, const wxString& title,
 310                  int x, int y, int w, int h)
 311        : wxFrame(frame, -1, title, wxPoint(x, y), wxSize(w, h))
 312 {
 313     m_nRunning = m_nCount = 0;
 314
 315     CreateStatusBar(2);
 316
 317     m_txtctrl = new wxTextCtrl(this, -1, "", wxPoint(0, 0), wxSize(0, 0),
 318                                wxTE_MULTILINE | wxTE_READONLY);
 319
 320 }
 321
 322 MyThread *MyFrame::CreateThread()
 323 {
 324     MyThread *thread = new MyThread(this);
 325
 326     if ( thread->Create() != wxTHREAD_NO_ERROR )
 327     {
 328         wxLogError("Can't create thread!");
 329     }
 330
 331     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 332     wxGetApp().m_threads.Add(thread);
 333
 334     return thread;
 335 }
 336
 337 void MyFrame::OnStartThreads(wxCommandEvent& WXUNUSED(event) )
 338 {
 339     static long s_num = 10;
 340
 341     s_num = wxGetNumberFromUser("How many threads to start: ", "",
 342                                 "wxThread sample", s_num, 1, 10000, this);
 343     if ( s_num == -1 )
 344     {
 345         s_num = 10;
 346
 347         return;
 348     }
 349
 350     size_t count = (size_t)s_num, n;
 351
 352     wxArrayThread threads;
 353
 354     // first create them all...
 355     for ( n = 0; n < count; n++ )
 356     {
 357         wxThread *thr = CreateThread();
 358
 359         // we want to show the effect of SetPriority(): the first thread will
 360         // have the lowest priority, the second - the highest, all the rest
 361         // the normal one
 362         if ( n == 0 )
 363             thr->SetPriority(WXTHREAD_MIN_PRIORITY);
 364         else if ( n == 1 )
 365             thr->SetPriority(WXTHREAD_MAX_PRIORITY);
 366         else
 367             thr->SetPriority(WXTHREAD_DEFAULT_PRIORITY);
 368
 369         threads.Add(thr);
 370     }
 371
 372     wxString msg;
 373     msg.Printf("%d new threads created.", count);
 374     SetStatusText(msg, 1);
 375
 376     // ...and then start them
 377     for ( n = 0; n < count; n++ )
 378     {
 379         threads[n]->Run();
 380     }
 381 }
 382
 383 void MyFrame::OnStartThread(wxCommandEvent& WXUNUSED(event) )
 384 {
 385     MyThread *thread = CreateThread();
 386
 387     if ( thread->Run() != wxTHREAD_NO_ERROR )
 388     {
 389         wxLogError("Can't start thread!");
 390     }
 391
 392     SetStatusText("New thread started.", 1);
 393 }
 394
 395 void MyFrame::OnStopThread(wxCommandEvent& WXUNUSED(event) )
 396 {
 397     // stop the last thread
 398     if ( wxGetApp().m_threads.IsEmpty() )
 399     {
 400         wxLogError("No thread to stop!");
 401     }
 402     else
 403     {
 404         wxGetApp().m_critsect.Enter();
 405
 406         wxThread *thread = wxGetApp().m_threads.Last();
 407
 408         // it's important to leave critical section before calling Delete()
 409         // because delete will (implicitly) call OnExit() which also tries
 410         // to enter the same crit section - would dead lock.
 411         wxGetApp().m_critsect.Leave();
 412
 413         thread->Delete();
 414
 415         SetStatusText("Thread stopped.", 1);
 416     }
 417 }
 418
 419 void MyFrame::OnResumeThread(wxCommandEvent& WXUNUSED(event) )
 420 {
 421     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 422
 423     // resume first suspended thread
 424     size_t n = 0, count = wxGetApp().m_threads.Count();
 425     while ( n < count && !wxGetApp().m_threads[n]->IsPaused() )
 426         n++;
 427
 428     if ( n == count )
 429     {
 430         wxLogError("No thread to resume!");
 431     }
 432     else
 433     {
 434         wxGetApp().m_threads[n]->Resume();
 435
 436         SetStatusText("Thread resumed.", 1);
 437     }
 438 }
 439
 440 void MyFrame::OnPauseThread(wxCommandEvent& WXUNUSED(event) )
 441 {
 442     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 443
 444     // pause last running thread
 445     int n = wxGetApp().m_threads.Count() - 1;
 446     while ( n >= 0 && !wxGetApp().m_threads[n]->IsRunning() )
 447         n--;
 448
 449     if ( n < 0 )
 450     {
 451         wxLogError("No thread to pause!");
 452     }
 453     else
 454     {
 455         wxGetApp().m_threads[n]->Pause();
 456
 457         SetStatusText("Thread paused.", 1);
 458     }
 459 }
 460
 461 // set the frame title indicating the current number of threads
 462 void MyFrame::OnIdle(wxIdleEvent &event)
 463 {
 464     // update the counts of running/total threads
 465     size_t nRunning = 0,
 466            nCount = wxGetApp().m_threads.Count();
 467     for ( size_t n = 0; n < nCount; n++ )
 468     {
 469         if ( wxGetApp().m_threads[n]->IsRunning() )
 470             nRunning++;
 471     }
 472
 473     if ( nCount != m_nCount || nRunning != m_nRunning )
 474     {
 475         m_nRunning = nRunning;
 476         m_nCount = nCount;
 477
 478         wxLogStatus(this, "%u threads total, %u running.", nCount, nRunning);
 479     }
 480     //else: avoid flicker - don't print anything
 481 }
 482
 483 void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event) )
 484 {
 485     size_t count = wxGetApp().m_threads.Count();
 486     for ( size_t i = 0; i < count; i++ )
 487     {
 488         wxGetApp().m_threads[0]->Delete();
 489     }
 490
 491     Close(TRUE);
 492 }
 493
 494 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event) )
 495 {
 496     wxMessageDialog dialog(this, "wxWindows multithreaded application sample\n"
 497                                  "(c) 1998 Julian Smart, Guilhem Lavaux\n"
 498                                  "(c) 1999 Vadim Zeitlin",
 499                            "About wxThread sample",
 500                            wxOK | wxICON_INFORMATION);
 501
 502     dialog.ShowModal();
 503 }
 504
 505 void MyFrame::OnClear(wxCommandEvent& WXUNUSED(event))
 506 {
 507     m_txtctrl->Clear();
 508 }
 509
 510 void MyFrame::OnStartWorker(wxCommandEvent& WXUNUSED(event))
 511 {
 512     MyWorkerThread *thread = new MyWorkerThread(this);
 513
 514     if ( thread->Create() != wxTHREAD_NO_ERROR )
 515     {
 516         wxLogError("Can't create thread!");
 517     }
 518
 519     thread->Run();
 520 }
 521
 522 void MyFrame::OnWorkerEvent(wxCommandEvent& WXUNUSED(event))
 523 {
 524     WriteText( "Got message from worker thread\n" );
 525 }
 526