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         wxString text;
 239         text.Printf("[%u] Thread 0x%x here!!", m_count, GetId());
 240
 241         // create any type of command event here
 242         wxCommandEvent event( wxEVT_COMMAND_MENU_SELECTED, WORKER_EVENT );
 243         event.SetInt( WORKER_EVENT );
 244         event.SetString( text );
 245
 246         // send in a thread-safe way
 247         wxPostEvent( m_frame, event );
 248
 249         // same as:
 250         // m_frame->AddPendingEvent( event );
 251
 252         // wxSleep() can't be called from non-main thread!
 253         wxThread::Sleep(1000);
 254     }
 255
 256     return NULL;
 257 }
 258
 259 //--------------------------------------------------
 260 // main program
 261 //--------------------------------------------------
 262
 263 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 264     EVT_MENU(TEST_QUIT, MyFrame::OnQuit)
 265     EVT_MENU(TEST_ABOUT, MyFrame::OnAbout)
 266     EVT_MENU(TEST_CLEAR, MyFrame::OnClear)
 267     EVT_MENU(TEST_START_THREAD, MyFrame::OnStartThread)
 268     EVT_MENU(TEST_START_THREADS, MyFrame::OnStartThreads)
 269     EVT_MENU(TEST_STOP_THREAD, MyFrame::OnStopThread)
 270     EVT_MENU(TEST_PAUSE_THREAD, MyFrame::OnPauseThread)
 271     EVT_MENU(TEST_RESUME_THREAD, MyFrame::OnResumeThread)
 272
 273     EVT_MENU(TEST_START_WORKER, MyFrame::OnStartWorker)
 274     EVT_MENU(WORKER_EVENT, MyFrame::OnWorkerEvent)
 275
 276     EVT_IDLE(MyFrame::OnIdle)
 277 END_EVENT_TABLE()
 278
 279 // `Main program' equivalent, creating windows and returning main app frame
 280 bool MyApp::OnInit()
 281 {
 282     // Create the main frame window
 283     MyFrame *frame = new MyFrame((wxFrame *)NULL, "wxWindows threads sample",
 284                                  50, 50, 450, 340);
 285
 286     // Make a menubar
 287     wxMenu *file_menu = new wxMenu;
 288
 289     file_menu->Append(TEST_CLEAR, "&Clear log\tCtrl-L");
 290     file_menu->AppendSeparator();
 291     file_menu->Append(TEST_ABOUT, "&About");
 292     file_menu->AppendSeparator();
 293     file_menu->Append(TEST_QUIT, "E&xit\tAlt-X");
 294     wxMenuBar *menu_bar = new wxMenuBar;
 295     menu_bar->Append(file_menu, "&File");
 296
 297     wxMenu *thread_menu = new wxMenu;
 298     thread_menu->Append(TEST_START_THREAD, "&Start a new thread\tCtrl-N");
 299     thread_menu->Append(TEST_START_THREADS, "Start &many threads at once");
 300     thread_menu->Append(TEST_STOP_THREAD, "S&top a running thread\tCtrl-S");
 301     thread_menu->AppendSeparator();
 302     thread_menu->Append(TEST_PAUSE_THREAD, "&Pause a running thread\tCtrl-P");
 303     thread_menu->Append(TEST_RESUME_THREAD, "&Resume suspended thread\tCtrl-R");
 304     thread_menu->AppendSeparator();
 305     thread_menu->Append(TEST_START_WORKER, "Start &worker thread\tCtrl-W");
 306
 307     menu_bar->Append(thread_menu, "&Thread");
 308     frame->SetMenuBar(menu_bar);
 309
 310     // Show the frame
 311     frame->Show(TRUE);
 312
 313     SetTopWindow(frame);
 314
 315     return TRUE;
 316 }
 317
 318 // My frame constructor
 319 MyFrame::MyFrame(wxFrame *frame, const wxString& title,
 320                  int x, int y, int w, int h)
 321        : wxFrame(frame, -1, title, wxPoint(x, y), wxSize(w, h))
 322 {
 323     m_nRunning = m_nCount = 0;
 324
 325     CreateStatusBar(2);
 326
 327     m_txtctrl = new wxTextCtrl(this, -1, "", wxPoint(0, 0), wxSize(0, 0),
 328                                wxTE_MULTILINE | wxTE_READONLY);
 329
 330 }
 331
 332 MyThread *MyFrame::CreateThread()
 333 {
 334     MyThread *thread = new MyThread(this);
 335
 336     if ( thread->Create() != wxTHREAD_NO_ERROR )
 337     {
 338         wxLogError("Can't create thread!");
 339     }
 340
 341     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 342     wxGetApp().m_threads.Add(thread);
 343
 344     return thread;
 345 }
 346
 347 void MyFrame::OnStartThreads(wxCommandEvent& WXUNUSED(event) )
 348 {
 349     static long s_num = 10;
 350
 351     s_num = wxGetNumberFromUser("How many threads to start: ", "",
 352                                 "wxThread sample", s_num, 1, 10000, this);
 353     if ( s_num == -1 )
 354     {
 355         s_num = 10;
 356
 357         return;
 358     }
 359
 360     size_t count = (size_t)s_num, n;
 361
 362     wxArrayThread threads;
 363
 364     // first create them all...
 365     for ( n = 0; n < count; n++ )
 366     {
 367         wxThread *thr = CreateThread();
 368
 369         // we want to show the effect of SetPriority(): the first thread will
 370         // have the lowest priority, the second - the highest, all the rest
 371         // the normal one
 372         if ( n == 0 )
 373             thr->SetPriority(WXTHREAD_MIN_PRIORITY);
 374         else if ( n == 1 )
 375             thr->SetPriority(WXTHREAD_MAX_PRIORITY);
 376         else
 377             thr->SetPriority(WXTHREAD_DEFAULT_PRIORITY);
 378
 379         threads.Add(thr);
 380     }
 381
 382     wxString msg;
 383     msg.Printf("%d new threads created.", count);
 384     SetStatusText(msg, 1);
 385
 386     // ...and then start them
 387     for ( n = 0; n < count; n++ )
 388     {
 389         threads[n]->Run();
 390     }
 391 }
 392
 393 void MyFrame::OnStartThread(wxCommandEvent& WXUNUSED(event) )
 394 {
 395     MyThread *thread = CreateThread();
 396
 397     if ( thread->Run() != wxTHREAD_NO_ERROR )
 398     {
 399         wxLogError("Can't start thread!");
 400     }
 401
 402     SetStatusText("New thread started.", 1);
 403 }
 404
 405 void MyFrame::OnStopThread(wxCommandEvent& WXUNUSED(event) )
 406 {
 407     // stop the last thread
 408     if ( wxGetApp().m_threads.IsEmpty() )
 409     {
 410         wxLogError("No thread to stop!");
 411     }
 412     else
 413     {
 414         wxGetApp().m_critsect.Enter();
 415
 416         wxThread *thread = wxGetApp().m_threads.Last();
 417
 418         // it's important to leave critical section before calling Delete()
 419         // because delete will (implicitly) call OnExit() which also tries
 420         // to enter the same crit section - would dead lock.
 421         wxGetApp().m_critsect.Leave();
 422
 423         thread->Delete();
 424
 425         SetStatusText("Thread stopped.", 1);
 426     }
 427 }
 428
 429 void MyFrame::OnResumeThread(wxCommandEvent& WXUNUSED(event) )
 430 {
 431     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 432
 433     // resume first suspended thread
 434     size_t n = 0, count = wxGetApp().m_threads.Count();
 435     while ( n < count && !wxGetApp().m_threads[n]->IsPaused() )
 436         n++;
 437
 438     if ( n == count )
 439     {
 440         wxLogError("No thread to resume!");
 441     }
 442     else
 443     {
 444         wxGetApp().m_threads[n]->Resume();
 445
 446         SetStatusText("Thread resumed.", 1);
 447     }
 448 }
 449
 450 void MyFrame::OnPauseThread(wxCommandEvent& WXUNUSED(event) )
 451 {
 452     wxCriticalSectionLocker enter(wxGetApp().m_critsect);
 453
 454     // pause last running thread
 455     int n = wxGetApp().m_threads.Count() - 1;
 456     while ( n >= 0 && !wxGetApp().m_threads[n]->IsRunning() )
 457         n--;
 458
 459     if ( n < 0 )
 460     {
 461         wxLogError("No thread to pause!");
 462     }
 463     else
 464     {
 465         wxGetApp().m_threads[n]->Pause();
 466
 467         SetStatusText("Thread paused.", 1);
 468     }
 469 }
 470
 471 // set the frame title indicating the current number of threads
 472 void MyFrame::OnIdle(wxIdleEvent &event)
 473 {
 474     // update the counts of running/total threads
 475     size_t nRunning = 0,
 476            nCount = wxGetApp().m_threads.Count();
 477     for ( size_t n = 0; n < nCount; n++ )
 478     {
 479         if ( wxGetApp().m_threads[n]->IsRunning() )
 480             nRunning++;
 481     }
 482
 483     if ( nCount != m_nCount || nRunning != m_nRunning )
 484     {
 485         m_nRunning = nRunning;
 486         m_nCount = nCount;
 487
 488         wxLogStatus(this, "%u threads total, %u running.", nCount, nRunning);
 489     }
 490     //else: avoid flicker - don't print anything
 491 }
 492
 493 void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event) )
 494 {
 495     size_t count = wxGetApp().m_threads.Count();
 496     for ( size_t i = 0; i < count; i++ )
 497     {
 498         wxGetApp().m_threads[0]->Delete();
 499     }
 500
 501     Close(TRUE);
 502 }
 503
 504 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event) )
 505 {
 506     wxMessageDialog dialog(this, "wxWindows multithreaded application sample\n"
 507                                  "(c) 1998 Julian Smart, Guilhem Lavaux\n"
 508                                  "(c) 1999 Vadim Zeitlin\n"
 509                                  "(c) 2000 Robert Roebling",
 510                            "About wxThread sample",
 511                            wxOK | wxICON_INFORMATION);
 512
 513     dialog.ShowModal();
 514 }
 515
 516 void MyFrame::OnClear(wxCommandEvent& WXUNUSED(event))
 517 {
 518     m_txtctrl->Clear();
 519 }
 520
 521 void MyFrame::OnStartWorker(wxCommandEvent& WXUNUSED(event))
 522 {
 523     MyWorkerThread *thread = new MyWorkerThread(this);
 524
 525     if ( thread->Create() != wxTHREAD_NO_ERROR )
 526     {
 527         wxLogError("Can't create thread!");
 528     }
 529
 530     thread->Run();
 531 }
 532
 533 void MyFrame::OnWorkerEvent(wxCommandEvent& event)
 534 {
 535     WriteText( "Got message from worker thread: " );
 536     WriteText( event.GetString() );
 537     WriteText( "\n" );
 538 }
 539