X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/cd5e9298159e58f57e05f3b76c9d4a45e1eefe12..f2c1b903bf400c6d4020758462b64129ca1e2d65:/samples/thread/thread.cpp diff --git a/samples/thread/thread.cpp b/samples/thread/thread.cpp index 48aef6531e..c6e7d0d2de 100644 --- a/samples/thread/thread.cpp +++ b/samples/thread/thread.cpp @@ -1,18 +1,21 @@ ///////////////////////////////////////////////////////////////////////////// // Name: thread.cpp -// Purpose: wxWindows thread sample -// Author: Julian Smart(minimal)/Guilhem Lavaux(thread test) +// Purpose: wxWidgets thread sample +// Author: Guilhem Lavaux, Vadim Zeitlin // Modified by: // Created: 06/16/98 // RCS-ID: $Id$ -// Copyright: (c) Julian Smart, Markus Holzem, Guilhem Lavaux +// Copyright: (c) 1998-2002 wxWidgets team // Licence: wxWindows license ///////////////////////////////////////////////////////////////////////////// -/* - TODO: use worker threads to update progress controls instead of writing - messages - it will be more visual - */ +// ============================================================================ +// declarations +// ============================================================================ + +// ---------------------------------------------------------------------------- +// headers +// ---------------------------------------------------------------------------- // For compilers that support precompilation, includes "wx/wx.h". #include "wx/wxprec.h" @@ -31,11 +34,22 @@ #include "wx/thread.h" #include "wx/dynarray.h" -#include "wx/time.h" - +#include "wx/numdlg.h" #include "wx/progdlg.h" +// ---------------------------------------------------------------------------- +// resources +// ---------------------------------------------------------------------------- + +#include "../sample.xpm" + +// ---------------------------------------------------------------------------- +// private classes +// ---------------------------------------------------------------------------- + +// define this to use wxExecute in the exec tests, otherwise just use system #define USE_EXECUTE + #ifdef USE_EXECUTE #define EXEC(cmd) wxExecute((cmd), wxEXEC_SYNC) #else @@ -43,40 +57,64 @@ #endif class MyThread; -WX_DEFINE_ARRAY(wxThread *, wxArrayThread); +WX_DEFINE_ARRAY_PTR(wxThread *, wxArrayThread); + +// ---------------------------------------------------------------------------- +// the application object +// ---------------------------------------------------------------------------- -// Define a new application type class MyApp : public wxApp { public: + MyApp(); + virtual ~MyApp(){}; + virtual bool OnInit(); -public: + // critical section protects access to all of the fields below + wxCriticalSection m_critsect; + // all the threads currently alive - as soon as the thread terminates, it's // removed from the array wxArrayThread m_threads; - // crit section protects access to all of the arrays below - wxCriticalSection m_critsect; + // semaphore used to wait for the threads to exit, see MyFrame::OnQuit() + wxSemaphore m_semAllDone; + + // indicates that we're shutting down and all threads should exit + bool m_shuttingDown; }; -// Create a new application object -IMPLEMENT_APP(MyApp) +// ---------------------------------------------------------------------------- +// the main application frame +// ---------------------------------------------------------------------------- -// Define a new frame type class MyFrame: public wxFrame { public: // ctor MyFrame(wxFrame *frame, const wxString& title, int x, int y, int w, int h); + virtual ~MyFrame(); - // operations - void WriteText(const wxString& text) { m_txtctrl->WriteText(text); } + // this function is MT-safe, i.e. it can be called from worker threads + // safely without any additional locking + void LogThreadMessage(const wxString& text) + { + wxCriticalSectionLocker lock(m_csMessages); + m_messages.push_back(text); + + // as we effectively log the messages from the idle event handler, + // ensure it's going to be called now that we have some messages to log + wxWakeUpIdle(); + } // accessors for MyWorkerThread (called in its context!) bool Cancelled(); - // callbacks +private: + // event handlers + // -------------- + void OnQuit(wxCommandEvent& event); void OnClear(wxCommandEvent& event); @@ -87,43 +125,64 @@ public: void OnResumeThread(wxCommandEvent& event); void OnStartWorker(wxCommandEvent& event); - void OnWorkerEvent(wxCommandEvent& event); - void OnUpdateWorker(wxUpdateUIEvent& event); - void OnExecMain(wxCommandEvent& event); - void OnExecThread(wxCommandEvent& event); + void OnStartGUIThread(wxCommandEvent& event); void OnShowCPUs(wxCommandEvent& event); void OnAbout(wxCommandEvent& event); void OnIdle(wxIdleEvent &event); + void OnWorkerEvent(wxThreadEvent& event); + void OnUpdateWorker(wxUpdateUIEvent& event); + + + // thread helper functions + // ----------------------- -private: // helper function - creates a new thread (but doesn't run it) MyThread *CreateThread(); + // update display in our status bar: called during idle handling + void UpdateThreadStatus(); + + // log the messages queued by LogThreadMessage() + void DoLogThreadMessages(); + + + // internal variables + // ------------------ + // just some place to put our messages in wxTextCtrl *m_txtctrl; + // the array of pending messages to be displayed and the critical section + // protecting it + wxArrayString m_messages; + wxCriticalSection m_csMessages; + // remember the number of running threads and total number of threads - size_t m_nRunning, m_nCount; + size_t m_nRunning, + m_nCount; // the progress dialog which we show while worker thread is running wxProgressDialog *m_dlgProgress; // was the worker thread cancelled by user? bool m_cancelled; - - // protects m_cancelled - wxCriticalSection m_critsectWork; + wxCriticalSection m_csCancelled; // protects m_cancelled DECLARE_EVENT_TABLE() }; +// ---------------------------------------------------------------------------- +// constants +// ---------------------------------------------------------------------------- + // ID for the menu commands enum { - THREAD_QUIT = 1, + THREAD_QUIT = wxID_EXIT, + THREAD_ABOUT = wxID_ABOUT, THREAD_TEXT = 101, THREAD_CLEAR, THREAD_START_THREAD = 201, @@ -131,101 +190,43 @@ enum THREAD_STOP_THREAD, THREAD_PAUSE_THREAD, THREAD_RESUME_THREAD, - THREAD_START_WORKER, + THREAD_START_WORKER, THREAD_EXEC_MAIN, - THREAD_EXEC_THREAD, + THREAD_START_GUI_THREAD, THREAD_SHOWCPUS, - THREAD_ABOUT, - WORKER_EVENT // this one gets sent from the worker thread + WORKER_EVENT = wxID_HIGHEST+1, // this one gets sent from MyWorkerThread + GUITHREAD_EVENT // this one gets sent from MyGUIThread }; // ---------------------------------------------------------------------------- -// GUI thread +// a simple thread // ---------------------------------------------------------------------------- class MyThread : public wxThread { public: MyThread(MyFrame *frame); + virtual ~MyThread(); // thread execution starts here virtual void *Entry(); - // called when the thread exits - whether it terminates normally or is - // stopped with Delete() (but not when it is Kill()ed!) - virtual void OnExit(); - - // write something to the text control - void WriteText(const wxString& text); + // write something to the text control in the main frame + void WriteText(const wxString& text) + { + m_frame->LogThreadMessage(text); + } public: - size_t m_count; + unsigned m_count; MyFrame *m_frame; }; -MyThread::MyThread(MyFrame *frame) - : wxThread() -{ - m_count = 0; - m_frame = frame; -} - -void MyThread::WriteText(const wxString& text) -{ - wxString msg; - - // before doing any GUI calls we must ensure that this thread is the only - // one doing it! - - wxMutexGuiEnter(); - - msg << text; - m_frame->WriteText(msg); - - wxMutexGuiLeave(); -} - -void MyThread::OnExit() -{ - wxCriticalSectionLocker locker(wxGetApp().m_critsect); - - wxGetApp().m_threads.Remove(this); -} - -void *MyThread::Entry() -{ - wxString text; - - text.Printf(wxT("Thread 0x%x started (priority = %d).\n"), - GetId(), GetPriority()); - WriteText(text); - // wxLogMessage(text); -- test wxLog thread safeness - - for ( m_count = 0; m_count < 10; m_count++ ) - { - // check if we were asked to exit - if ( TestDestroy() ) - break; - - text.Printf(wxT("[%u] Thread 0x%x here.\n"), m_count, GetId()); - WriteText(text); - - // wxSleep() can't be called from non-GUI thread! - wxThread::Sleep(1000); - } - - text.Printf(wxT("Thread 0x%x finished.\n"), GetId()); - WriteText(text); - // wxLogMessage(text); -- test wxLog thread safeness - - return NULL; -} - // ---------------------------------------------------------------------------- -// worker thread +// a worker thread // ---------------------------------------------------------------------------- class MyWorkerThread : public wxThread @@ -242,70 +243,95 @@ public: public: MyFrame *m_frame; - size_t m_count; + unsigned m_count; }; -MyWorkerThread::MyWorkerThread(MyFrame *frame) - : wxThread() -{ - m_frame = frame; - m_count = 0; -} +// ---------------------------------------------------------------------------- +// a thread which executes GUI calls using wxMutexGuiEnter/Leave +// ---------------------------------------------------------------------------- -void MyWorkerThread::OnExit() -{ -} +#define GUITHREAD_BMP_SIZE 300 +#define GUITHREAD_NUM_UPDATES 50 +class MyImageDialog; -void *MyWorkerThread::Entry() +class MyGUIThread : public wxThread { - for ( m_count = 0; !m_frame->Cancelled() && (m_count < 100); m_count++ ) +public: + MyGUIThread(MyImageDialog *dlg) : wxThread(wxTHREAD_JOINABLE) { - // check if we were asked to exit - if ( TestDestroy() ) - break; - - // create any type of command event here - wxCommandEvent event( wxEVT_COMMAND_MENU_SELECTED, WORKER_EVENT ); - event.SetInt( m_count ); - - // send in a thread-safe way - wxPostEvent( m_frame, event ); - - // wxSleep() can't be called from non-main thread! - wxThread::Sleep(200); + m_dlg = dlg; } - wxCommandEvent event( wxEVT_COMMAND_MENU_SELECTED, WORKER_EVENT ); - event.SetInt(-1); // that's all - wxPostEvent( m_frame, event ); + virtual ExitCode Entry(); - return NULL; -} +private: + MyImageDialog *m_dlg; +}; // ---------------------------------------------------------------------------- -// a thread which simply calls wxExecute +// an helper dialog used by MyFrame::OnStartGUIThread // ---------------------------------------------------------------------------- -class MyExecThread : public wxThread +class MyImageDialog: public wxDialog { public: - MyExecThread(const wxChar *command) : wxThread(wxTHREAD_JOINABLE), - m_command(command) - { - Create(); - } + // ctor + MyImageDialog(wxFrame *frame); + ~MyImageDialog(); - virtual ExitCode Entry() - { - return (ExitCode)EXEC(m_command); - } + // stuff used by MyGUIThread: + wxBitmap m_bmp; // the bitmap drawn by MyGUIThread + wxCriticalSection m_csBmp; // protects m_bmp private: - wxString m_command; + void OnGUIThreadEvent(wxThreadEvent& event); + void OnPaint(wxPaintEvent&); + + MyGUIThread m_thread; + int m_nCurrentProgress; + + DECLARE_EVENT_TABLE() }; -// ---------------------------------------------------------------------------- +// ============================================================================ // implementation +// ============================================================================ + +// ---------------------------------------------------------------------------- +// the application class +// ---------------------------------------------------------------------------- + +// Create a new application object +IMPLEMENT_APP(MyApp) + +MyApp::MyApp() +{ + m_shuttingDown = false; +} + +// `Main program' equivalent, creating windows and returning main app frame +bool MyApp::OnInit() +{ + if ( !wxApp::OnInit() ) + return false; + + // uncomment this to get some debugging messages from the trace code + // on the console (or just set WXTRACE env variable to include "thread") + wxLog::AddTraceMask("thread"); + + // Create the main frame window + MyFrame *frame = new MyFrame((wxFrame *)NULL, _T("wxWidgets threads sample"), + 50, 50, 450, 340); + SetTopWindow(frame); + + // Show the frame + frame->Show(true); + + return true; +} + +// ---------------------------------------------------------------------------- +// MyFrame // ---------------------------------------------------------------------------- BEGIN_EVENT_TABLE(MyFrame, wxFrame) @@ -317,85 +343,93 @@ BEGIN_EVENT_TABLE(MyFrame, wxFrame) EVT_MENU(THREAD_PAUSE_THREAD, MyFrame::OnPauseThread) EVT_MENU(THREAD_RESUME_THREAD, MyFrame::OnResumeThread) + EVT_MENU(THREAD_START_WORKER, MyFrame::OnStartWorker) EVT_MENU(THREAD_EXEC_MAIN, MyFrame::OnExecMain) - EVT_MENU(THREAD_EXEC_THREAD, MyFrame::OnExecThread) + EVT_MENU(THREAD_START_GUI_THREAD, MyFrame::OnStartGUIThread) EVT_MENU(THREAD_SHOWCPUS, MyFrame::OnShowCPUs) EVT_MENU(THREAD_ABOUT, MyFrame::OnAbout) EVT_UPDATE_UI(THREAD_START_WORKER, MyFrame::OnUpdateWorker) - EVT_MENU(THREAD_START_WORKER, MyFrame::OnStartWorker) - EVT_MENU(WORKER_EVENT, MyFrame::OnWorkerEvent) - + EVT_THREAD(WORKER_EVENT, MyFrame::OnWorkerEvent) EVT_IDLE(MyFrame::OnIdle) END_EVENT_TABLE() -// `Main program' equivalent, creating windows and returning main app frame -bool MyApp::OnInit() +// My frame constructor +MyFrame::MyFrame(wxFrame *frame, const wxString& title, + int x, int y, int w, int h) + : wxFrame(frame, wxID_ANY, title, wxPoint(x, y), wxSize(w, h)) { - // uncomment this to get some debugging messages from the trace code - // on the console (or just set WXTRACE env variable to include "thread") - //wxLog::AddTraceMask("thread"); - - // Create the main frame window - MyFrame *frame = new MyFrame((wxFrame *)NULL, "wxWindows threads sample", - 50, 50, 450, 340); + SetIcon(wxIcon(sample_xpm)); // Make a menubar wxMenuBar *menuBar = new wxMenuBar; wxMenu *menuFile = new wxMenu; - menuFile->Append(THREAD_CLEAR, "&Clear log\tCtrl-L"); + menuFile->Append(THREAD_CLEAR, _T("&Clear log\tCtrl-L")); menuFile->AppendSeparator(); - menuFile->Append(THREAD_QUIT, "E&xit\tAlt-X"); - menuBar->Append(menuFile, "&File"); + menuFile->Append(THREAD_QUIT, _T("E&xit\tAlt-X")); + menuBar->Append(menuFile, _T("&File")); wxMenu *menuThread = new wxMenu; - menuThread->Append(THREAD_START_THREAD, "&Start a new thread\tCtrl-N"); - menuThread->Append(THREAD_START_THREADS, "Start &many threads at once"); - menuThread->Append(THREAD_STOP_THREAD, "S&top a running thread\tCtrl-S"); + menuThread->Append(THREAD_START_THREAD, _T("&Start a new thread\tCtrl-N")); + menuThread->Append(THREAD_START_THREADS, _T("Start &many threads at once")); + menuThread->Append(THREAD_STOP_THREAD, _T("S&top the last spawned thread\tCtrl-S")); menuThread->AppendSeparator(); - menuThread->Append(THREAD_PAUSE_THREAD, "&Pause a running thread\tCtrl-P"); - menuThread->Append(THREAD_RESUME_THREAD, "&Resume suspended thread\tCtrl-R"); + menuThread->Append(THREAD_PAUSE_THREAD, _T("&Pause the last spawned running thread\tCtrl-P")); + menuThread->Append(THREAD_RESUME_THREAD, _T("&Resume the first suspended thread\tCtrl-R")); menuThread->AppendSeparator(); - menuThread->Append(THREAD_START_WORKER, "Start &worker thread\tCtrl-W"); - menuBar->Append(menuThread, "&Thread"); - - wxMenu *menuExec = new wxMenu; - menuExec->Append(THREAD_EXEC_MAIN, "&Launch a program from main thread\tF5"); - menuExec->Append(THREAD_EXEC_THREAD, "L&aunch a program from a thread\tCtrl-F5"); - menuBar->Append(menuExec, "&Execute"); + menuThread->Append(THREAD_START_WORKER, _T("Start a &worker thread\tCtrl-W")); + menuThread->Append(THREAD_EXEC_MAIN, _T("&Launch a program from main thread\tF5")); + menuThread->Append(THREAD_START_GUI_THREAD, _T("Launch a &GUI thread\tF6")); + menuBar->Append(menuThread, _T("&Thread")); wxMenu *menuHelp = new wxMenu; - menuHelp->Append(THREAD_SHOWCPUS, "&Show CPU count"); + menuHelp->Append(THREAD_SHOWCPUS, _T("&Show CPU count")); menuHelp->AppendSeparator(); - menuHelp->Append(THREAD_ABOUT, "&About..."); - menuBar->Append(menuHelp, "&Help"); + menuHelp->Append(THREAD_ABOUT, _T("&About...")); + menuBar->Append(menuHelp, _T("&Help")); - frame->SetMenuBar(menuBar); + SetMenuBar(menuBar); - // Show the frame - frame->Show(TRUE); + m_nRunning = m_nCount = 0; - SetTopWindow(frame); + m_dlgProgress = (wxProgressDialog *)NULL; - return TRUE; +#if wxUSE_STATUSBAR + CreateStatusBar(2); +#endif // wxUSE_STATUSBAR + + m_txtctrl = new wxTextCtrl(this, wxID_ANY, _T(""), wxPoint(0, 0), wxSize(0, 0), + wxTE_MULTILINE | wxTE_READONLY); } -// My frame constructor -MyFrame::MyFrame(wxFrame *frame, const wxString& title, - int x, int y, int w, int h) - : wxFrame(frame, -1, title, wxPoint(x, y), wxSize(w, h)) +MyFrame::~MyFrame() { - m_nRunning = m_nCount = 0; + // NB: although the OS will terminate all the threads anyhow when the main + // one exits, it's good practice to do it ourselves -- even if it's not + // completely trivial in this example - m_dlgProgress = (wxProgressDialog *)NULL; + // tell all the threads to terminate: note that they can't terminate while + // we're deleting them because they will block in their OnExit() -- this is + // important as otherwise we might access invalid array elements - CreateStatusBar(2); + { + wxCriticalSectionLocker locker(wxGetApp().m_critsect); - m_txtctrl = new wxTextCtrl(this, -1, "", wxPoint(0, 0), wxSize(0, 0), - wxTE_MULTILINE | wxTE_READONLY); + // check if we have any threads running first + const wxArrayThread& threads = wxGetApp().m_threads; + size_t count = threads.GetCount(); + + if ( !count ) + return; + + // set the flag indicating that all threads should exit + wxGetApp().m_shuttingDown = true; + } + // now wait for them to really terminate + wxGetApp().m_semAllDone.Wait(); } MyThread *MyFrame::CreateThread() @@ -413,12 +447,59 @@ MyThread *MyFrame::CreateThread() return thread; } +void MyFrame::DoLogThreadMessages() +{ + wxCriticalSectionLocker lock(m_csMessages); + + const size_t count = m_messages.size(); + for ( size_t n = 0; n < count; n++ ) + { + m_txtctrl->AppendText(m_messages[n]); + } + + m_messages.clear(); +} + +void MyFrame::UpdateThreadStatus() +{ + wxCriticalSectionLocker enter(wxGetApp().m_critsect); + + // update the counts of running/total threads + size_t nRunning = 0, + nCount = wxGetApp().m_threads.Count(); + for ( size_t n = 0; n < nCount; n++ ) + { + if ( wxGetApp().m_threads[n]->IsRunning() ) + nRunning++; + } + + if ( nCount != m_nCount || nRunning != m_nRunning ) + { + m_nRunning = nRunning; + m_nCount = nCount; + + wxLogStatus(this, wxT("%u threads total, %u running."), unsigned(nCount), unsigned(nRunning)); + } + //else: avoid flicker - don't print anything +} + +bool MyFrame::Cancelled() +{ + wxCriticalSectionLocker lock(m_csCancelled); + + return m_cancelled; +} + +// ---------------------------------------------------------------------------- +// MyFrame - event handlers +// ---------------------------------------------------------------------------- + void MyFrame::OnStartThreads(wxCommandEvent& WXUNUSED(event) ) { - static long s_num = 10; + static long s_num; - s_num = wxGetNumberFromUser("How many threads to start: ", "", - "wxThread sample", s_num, 1, 10000, this); + s_num = wxGetNumberFromUser(_T("How many threads to start: "), _T(""), + _T("wxThread sample"), s_num, 1, 10000, this); if ( s_num == -1 ) { s_num = 10; @@ -426,7 +507,7 @@ void MyFrame::OnStartThreads(wxCommandEvent& WXUNUSED(event) ) return; } - size_t count = (size_t)s_num, n; + unsigned count = unsigned(s_num), n; wxArrayThread threads; @@ -448,9 +529,11 @@ void MyFrame::OnStartThreads(wxCommandEvent& WXUNUSED(event) ) threads.Add(thr); } +#if wxUSE_STATUSBAR wxString msg; msg.Printf(wxT("%d new threads created."), count); SetStatusText(msg, 1); +#endif // wxUSE_STATUSBAR // ...and then start them for ( n = 0; n < count; n++ ) @@ -468,32 +551,27 @@ void MyFrame::OnStartThread(wxCommandEvent& WXUNUSED(event) ) wxLogError(wxT("Can't start thread!")); } - SetStatusText("New thread started.", 1); +#if wxUSE_STATUSBAR + SetStatusText(_T("New thread started."), 1); +#endif // wxUSE_STATUSBAR } void MyFrame::OnStopThread(wxCommandEvent& WXUNUSED(event) ) { - wxGetApp().m_critsect.Enter(); + wxCriticalSectionLocker enter(wxGetApp().m_critsect); // stop the last thread if ( wxGetApp().m_threads.IsEmpty() ) { wxLogError(wxT("No thread to stop!")); - - wxGetApp().m_critsect.Leave(); } else { - wxThread *thread = wxGetApp().m_threads.Last(); - - // it's important to leave critical section before calling Delete() - // because delete will (implicitly) call OnExit() which also tries - // to enter the same crit section - would dead lock. - wxGetApp().m_critsect.Leave(); + wxGetApp().m_threads.Last()->Delete(); - thread->Delete(); - - SetStatusText("Thread stopped.", 1); +#if wxUSE_STATUSBAR + SetStatusText(_T("Last thread stopped."), 1); +#endif // wxUSE_STATUSBAR } } @@ -514,7 +592,9 @@ void MyFrame::OnResumeThread(wxCommandEvent& WXUNUSED(event) ) { wxGetApp().m_threads[n]->Resume(); - SetStatusText("Thread resumed.", 1); +#if wxUSE_STATUSBAR + SetStatusText(_T("Thread resumed."), 1); +#endif // wxUSE_STATUSBAR } } @@ -535,56 +615,41 @@ void MyFrame::OnPauseThread(wxCommandEvent& WXUNUSED(event) ) { wxGetApp().m_threads[n]->Pause(); - SetStatusText("Thread paused.", 1); +#if wxUSE_STATUSBAR + SetStatusText(_T("Thread paused."), 1); +#endif // wxUSE_STATUSBAR } } -// set the frame title indicating the current number of threads -void MyFrame::OnIdle(wxIdleEvent &event) +void MyFrame::OnIdle(wxIdleEvent& event) { - // update the counts of running/total threads - size_t nRunning = 0, - nCount = wxGetApp().m_threads.Count(); - for ( size_t n = 0; n < nCount; n++ ) - { - if ( wxGetApp().m_threads[n]->IsRunning() ) - nRunning++; - } + DoLogThreadMessages(); - if ( nCount != m_nCount || nRunning != m_nRunning ) - { - m_nRunning = nRunning; - m_nCount = nCount; + UpdateThreadStatus(); - wxLogStatus(this, wxT("%u threads total, %u running."), nCount, nRunning); - } - //else: avoid flicker - don't print anything + event.Skip(); } void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event) ) { - size_t count = wxGetApp().m_threads.Count(); - for ( size_t i = 0; i < count; i++ ) - { - wxGetApp().m_threads[0]->Delete(); - } - - Close(TRUE); + Close(true); } void MyFrame::OnExecMain(wxCommandEvent& WXUNUSED(event)) { - wxLogMessage("The exit code from the main program is %ld", - EXEC("/bin/echo \"main program\"")); -} - -void MyFrame::OnExecThread(wxCommandEvent& WXUNUSED(event)) -{ - MyExecThread thread("/bin/echo \"child thread\""); - thread.Run(); + wxString cmd = wxGetTextFromUser("Please enter the command to execute", + "Enter command", +#ifdef __WXMSW__ + "notepad", +#else + "/bin/echo \"Message from another process\"", +#endif + this); + if (cmd.IsEmpty()) + return; // user clicked cancel - wxLogMessage("The exit code from a child thread is %ld", - (long)thread.Wait()); + wxLogMessage(wxT("The exit code from the main program is %ld"), + EXEC(cmd)); } void MyFrame::OnShowCPUs(wxCommandEvent& WXUNUSED(event)) @@ -595,31 +660,32 @@ void MyFrame::OnShowCPUs(wxCommandEvent& WXUNUSED(event)) switch ( nCPUs ) { case -1: - msg = "Unknown number of CPUs"; + msg = _T("Unknown number of CPUs"); break; case 0: - msg = "WARNING: you're running without any CPUs!"; + msg = _T("WARNING: you're running without any CPUs!"); break; case 1: - msg = "This system only has one CPU."; + msg = _T("This system only has one CPU."); break; default: - msg.Printf("This system has %d CPUs", nCPUs); + msg.Printf(wxT("This system has %d CPUs"), nCPUs); } - + wxLogMessage(msg); } void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event) ) { - wxMessageDialog dialog(this, "wxWindows multithreaded application sample\n" - "(c) 1998 Julian Smart, Guilhem Lavaux\n" - "(c) 1999 Vadim Zeitlin\n" - "(c) 2000 Robert Roebling", - "About wxThread sample", + wxMessageDialog dialog(this, + _T("wxWidgets multithreaded application sample\n") + _T("(c) 1998 Julian Smart, Guilhem Lavaux\n") + _T("(c) 1999 Vadim Zeitlin\n") + _T("(c) 2000 Robert Roebling"), + _T("About wxThread sample"), wxOK | wxICON_INFORMATION); dialog.ShowModal(); @@ -642,12 +708,13 @@ void MyFrame::OnStartWorker(wxCommandEvent& WXUNUSED(event)) if ( thread->Create() != wxTHREAD_NO_ERROR ) { wxLogError(wxT("Can't create thread!")); + return; } m_dlgProgress = new wxProgressDialog ( - "Progress dialog", - "Wait until the thread terminates or press [Cancel]", + _T("Progress dialog"), + _T("Wait until the thread terminates or press [Cancel]"), 100, this, wxPD_CAN_ABORT | @@ -658,18 +725,13 @@ void MyFrame::OnStartWorker(wxCommandEvent& WXUNUSED(event)) ); // thread is not running yet, no need for crit sect - m_cancelled = FALSE; + m_cancelled = false; thread->Run(); } -void MyFrame::OnWorkerEvent(wxCommandEvent& event) +void MyFrame::OnWorkerEvent(wxThreadEvent& event) { -#if 0 - WriteText( "Got message from worker thread: " ); - WriteText( event.GetString() ); - WriteText( "\n" ); -#else int n = event.GetInt(); if ( n == -1 ) { @@ -685,17 +747,264 @@ void MyFrame::OnWorkerEvent(wxCommandEvent& event) { if ( !m_dlgProgress->Update(n) ) { - wxCriticalSectionLocker lock(m_critsectWork); + wxCriticalSectionLocker lock(m_csCancelled); + + m_cancelled = true; + } + } +} + +void MyFrame::OnStartGUIThread(wxCommandEvent& WXUNUSED(event)) +{ + MyImageDialog dlg(this); + + dlg.ShowModal(); +} + + +// ---------------------------------------------------------------------------- +// MyImageDialog +// ---------------------------------------------------------------------------- + +BEGIN_EVENT_TABLE(MyImageDialog, wxDialog) + EVT_THREAD(GUITHREAD_EVENT, MyImageDialog::OnGUIThreadEvent) + EVT_PAINT(MyImageDialog::OnPaint) +END_EVENT_TABLE() + +MyImageDialog::MyImageDialog(wxFrame *parent) + : wxDialog(parent, wxID_ANY, "Image created by a secondary thread", + wxDefaultPosition, wxSize(GUITHREAD_BMP_SIZE,GUITHREAD_BMP_SIZE)*1.5, wxDEFAULT_DIALOG_STYLE), + m_thread(this) +{ + m_nCurrentProgress = 0; + + CentreOnScreen(); + + // NOTE: no need to lock m_csBmp until the thread isn't started: + + // create the bitmap + if (!m_bmp.Create(GUITHREAD_BMP_SIZE,GUITHREAD_BMP_SIZE) || !m_bmp.IsOk()) + { + wxLogError("Couldn't create the bitmap!"); + return; + } + + // clean it + wxMemoryDC dc(m_bmp); + dc.SetBackground(*wxBLACK_BRUSH); + dc.Clear(); + + // draw the bitmap from a secondary thread + if ( m_thread.Create() != wxTHREAD_NO_ERROR || + m_thread.Run() != wxTHREAD_NO_ERROR ) + { + wxLogError(wxT("Can't create/run thread!")); + return; + } +} + +MyImageDialog::~MyImageDialog() +{ + // in case our thread is still running and for some reason we are destroyed, + // do wait for the thread to complete as it assumes that its MyImageDialog + // pointer is always valid + m_thread.Delete(); +} + +void MyImageDialog::OnGUIThreadEvent(wxThreadEvent& event) +{ + m_nCurrentProgress = int(((float)event.GetInt()*100)/GUITHREAD_NUM_UPDATES); + + Refresh(); +} + +void MyImageDialog::OnPaint(wxPaintEvent& WXUNUSED(evt)) +{ + wxPaintDC dc(this); + + const wxSize& sz = dc.GetSize(); + + { + // paint the bitmap + wxCriticalSectionLocker locker(m_csBmp); + dc.DrawBitmap(m_bmp, (sz.GetWidth()-GUITHREAD_BMP_SIZE)/2, + (sz.GetHeight()-GUITHREAD_BMP_SIZE)/2); + } + + // paint a sort of progress bar with a 10px border: + dc.SetBrush(*wxRED_BRUSH); + dc.DrawRectangle(10,10, m_nCurrentProgress*(sz.GetWidth()-20)/100,30); + dc.SetTextForeground(*wxBLUE); + dc.DrawText(wxString::Format("%d%%", m_nCurrentProgress), + (sz.GetWidth()-dc.GetCharWidth()*2)/2, + 25-dc.GetCharHeight()/2); +} + +// ---------------------------------------------------------------------------- +// MyThread +// ---------------------------------------------------------------------------- + +MyThread::MyThread(MyFrame *frame) + : wxThread() +{ + m_count = 0; + m_frame = frame; +} + +MyThread::~MyThread() +{ + wxCriticalSectionLocker locker(wxGetApp().m_critsect); + + wxArrayThread& threads = wxGetApp().m_threads; + threads.Remove(this); + + if ( threads.IsEmpty() ) + { + // signal the main thread that there are no more threads left if it is + // waiting for us + if ( wxGetApp().m_shuttingDown ) + { + wxGetApp().m_shuttingDown = false; + + wxGetApp().m_semAllDone.Post(); + } + } +} + +wxThread::ExitCode MyThread::Entry() +{ + wxString text; - m_cancelled = TRUE; + text.Printf(wxT("Thread %p started (priority = %u).\n"), + GetId(), GetPriority()); + WriteText(text); + // wxLogMessage(text); -- test wxLog thread safeness + + for ( m_count = 0; m_count < 10; m_count++ ) + { + // check if the application is shutting down: in this case all threads + // should stop a.s.a.p. + { + wxCriticalSectionLocker locker(wxGetApp().m_critsect); + if ( wxGetApp().m_shuttingDown ) + return NULL; } + + // check if just this thread was asked to exit + if ( TestDestroy() ) + break; + + text.Printf(wxT("[%u] Thread %p here.\n"), m_count, GetId()); + WriteText(text); + + // wxSleep() can't be called from non-GUI thread! + wxThread::Sleep(1000); + } + + text.Printf(wxT("Thread %p finished.\n"), GetId()); + WriteText(text); + // wxLogMessage(text); -- test wxLog thread safeness + + return NULL; +} + + +// ---------------------------------------------------------------------------- +// MyWorkerThread +// ---------------------------------------------------------------------------- + +// define this symbol to 1 to test if the YieldFor() call in the wxProgressDialog::Update +// function provokes a race condition in which the second wxThreadEvent posted by +// MyWorkerThread::Entry is processed by the YieldFor() call of wxProgressDialog::Update +// and results in the destruction of the progress dialog itself, resulting in a crash later. +#define TEST_YIELD_RACE_CONDITION 0 + +MyWorkerThread::MyWorkerThread(MyFrame *frame) + : wxThread() +{ + m_frame = frame; + m_count = 0; +} + +void MyWorkerThread::OnExit() +{ +} + +wxThread::ExitCode MyWorkerThread::Entry() +{ +#if TEST_YIELD_RACE_CONDITION + if ( TestDestroy() ) + return NULL; + + wxThreadEvent event( wxEVT_COMMAND_THREAD, WORKER_EVENT ); + + event.SetInt( 50 ); + wxQueueEvent( m_frame, event.Clone() ); + + event.SetInt(-1); + wxQueueEvent( m_frame, event.Clone() ); +#else + for ( m_count = 0; !m_frame->Cancelled() && (m_count < 100); m_count++ ) + { + // check if we were asked to exit + if ( TestDestroy() ) + break; + + // create any type of command event here + wxThreadEvent event( wxEVT_COMMAND_THREAD, WORKER_EVENT ); + event.SetInt( m_count ); + + // send in a thread-safe way + wxQueueEvent( m_frame, event.Clone() ); + + wxMilliSleep(200); } + + wxThreadEvent event( wxEVT_COMMAND_THREAD, WORKER_EVENT ); + event.SetInt(-1); // that's all + wxQueueEvent( m_frame, event.Clone() ); #endif + + return NULL; } -bool MyFrame::Cancelled() + +// ---------------------------------------------------------------------------- +// MyGUIThread +// ---------------------------------------------------------------------------- + +wxThread::ExitCode MyGUIThread::Entry() { - wxCriticalSectionLocker lock(m_critsectWork); + for (int i=0; im_csBmp); + + // draw some more stuff on the bitmap + wxMemoryDC dc(m_dlg->m_bmp); + dc.SetBrush((i%2)==0 ? *wxBLUE_BRUSH : *wxGREEN_BRUSH); + dc.DrawRectangle(rand()%GUITHREAD_BMP_SIZE, rand()%GUITHREAD_BMP_SIZE, 30, 30); + + // simulate long drawing time: + wxMilliSleep(200); + } + + // if we don't release the GUI mutex the MyImageDialog won't be able to refresh + wxMutexGuiLeave(); + + // notify the dialog that another piece of our masterpiece is complete: + wxThreadEvent event( wxEVT_COMMAND_THREAD, GUITHREAD_EVENT ); + event.SetInt(i+1); + wxQueueEvent( m_dlg, event.Clone() ); + + // give the main thread the time to refresh before we lock the GUI mutex again + // FIXME: find a better way to do this! + wxMilliSleep(100); + } + + return (ExitCode)0; }